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4,000 | Suppose that you have an abstract for a scientific paper: we present 7 mm very large array continuum images of the starburst galaxy m82 . on arcsecond scales ,
two - thirds of the 7 mm continuum consists of free - free emission from hii regions . in the subarcsecond resolution map ,
we identify 14 compact sources , including 9 bright hii regions with @xmath0 .
four of the hii regions have rising spectra , implying emission measures @xmath1 @xmath2 pc . except for one compact source with peculiar features ,
all other compact radio sources are found in dust lanes and do not have optical or near - infrared continuum counterparts .
four regions of extended , high brightness ( em @xmath3 ) radio emission are found in our high resolution map , including some as large as @xmath42 , or 30 pc , representing either associations of small hii regions , or sheetlike structures of denser gas .
the good correlation between 7 mm emission and _ spitzer _
irac @xmath5 continuum - removed pah feature suggests that pah emission may track the recently formed ob stars .
we find an excellent correlation between molecular gas and star formation , particularly dense gas traced by hcn , down to the @xmath4 45 pc scale in m82 .
we also find star formation efficiencies ( sfes ) of 110% on the same scale , based on co maps .
the highest sfe are found in regions with the highest dense gas fractions . .
And you have already written the first three sentences of the full article: free - free emission from hii regions at radio wavelengths is a good tracer of young and heavily embedded regions of massive star formation such as luminous starbursts and nuclear star forming regions , where visual extinctions can be tens @xcite to hundreds of magnitudes , affecting even near and mid - infrared observations .
extragalactic continuum emission is complicated by the presence of non - thermal synchrotron emission within the beam , particularly at wavelengths longer than 6 cm . while it is possible in theory to do a spectral and spatial separation of free - free and synchrotron emission @xcite with multi - wavelength observations , the free - free emission can be most easily measured at millimeter wavelengths , where radio synchrotron has declined and
dust has not yet begun to take over ..
Please generate the next two sentences of the article | the enhanced high frequency capabilities of the very large array ( vla ) improved k and q band receivers , fast - switching calibration techniques allow us to detect and resolve the free - free emission from large hii regions in nearby galaxies .
we report vla observations of the 7 mm continuum emission of the starburst galaxy m82 . |
4,001 | Suppose that you have an abstract for a scientific paper: we present results of a large area ccd survey for low surface brightness galaxies ( lsbs ) that reaches central surface brightnesses of @xmath0 in @xmath1 .
we have analyzed @xmath2 of transit scan data , and identified a statistical subset of 7 pure disk lsb s with central surface brightnesses fainter than @xmath3 and with angular exponential scale lengths larger than @xmath4 .
the lsb detection is entirely automated , and the selection efficiency of the survey is well - quantified . after correcting for the selection efficiency , we find a surface density of @xmath5 for lsbs in the considered range of @xmath6 and @xmath7 ( 90% confidence levels ) , with the largest correction being due to the area lost behind bright stars , and the difficulty in detecting lsbs with small angular sizes .
we have measured redshifts to the final sample of lsbs , and find them to be at distances comparable to those probed by large galaxy catalogs , and to have intrinsic scale lengths of @xmath8 , also comparable to normal galaxies .
we use the redshifts and the selection efficiency to calculate the number density in lsbs with @xmath9 and find @xmath10 , with 90% confidence .
the measurement of the absolute number density of lsbs probably represents a lower limit , due to very strong biases against lsbs with bulges or edge - on lsbs in our sample . comparing the lsb number density to the number density of normal galaxies with either similar scale lengths or similar luminosities
, we find that the number density of lsbs with @xmath9 is comparable to or greater than the number density of normal galaxies .
the luminosity density in lsbs is comparable to the luminosity density of normal galaxies with similar luminosities , but is a factor of 3 - 10 smaller than the luminosity density of normal galaxies with similar scale lengths .
the relative lsb number density and luminosity density agree well with the theoretical predictions of dalcanton et al .
( 1997 ) .
the redshift - space distribution of the lsbs....
And you have already written the first three sentences of the full article: during the past twenty years , there has been a developing appreciation of the strong biases against finding galaxies of low surface brightness .
these biases arise because the night sky is not particularly dark .
airglow , zodiacal light , and undetected stars and galaxies combine to create a optical background whose surface brightness is as bright as the extrapolated central surface brightnesses of large spiral galaxy disks ..
Please generate the next two sentences of the article | with such a bright background , the ability to detect a galaxy depends not only upon the integrated luminosity of the galaxy , but also upon the contrast with which the galaxy stands out above the poisson fluctuations in the background .
a compact , high - surface brightness galaxy might be quite easy to detect , while another galaxy with the same total luminosity but with a much more extended , low - surface brightness structure would be difficult to find . while astronomers routinely consider the limiting magnitude of their galaxy catalogs , only recently have they begun to consider the ways in which surface brightness selection effects shape existing galaxy catalogs . as an example , freeman ( 1970 ) had initially showed that spiral galaxies share the same central surface brightness , with very little dispersion : @xmath11 . |
4,002 | Suppose that you have an abstract for a scientific paper: protocols of quantum energy teleportation ( qet ) , while retaining causality and local energy conservation , enable the transportation of energy from a subsystem of a many - body quantum system to a distant subsystem by local operations and classical communication through ground - state entanglement . we prove two energy - entanglement inequalities for a minimal qet model .
these relations help us to gain a profound understanding of entanglement itself as a physical resource by relating entanglement to energy as an evident physical resource .
+ + + + + _ department of physics , faculty of science , tohoku university , + sendai 980 - 8578 , japan + [email protected]_ .
And you have already written the first three sentences of the full article: the relationship between energy and information has been investigated extensively in the context of computation energy cost including a modern analysis of maxwell s demon @xcite-@xcite . in this letter , we show a new energy - information relation from a different point of view .
recently , it has been reported that energy can be transported by local operations and classical communication while retaining local energy conservation and without breaking causality @xcite-@xcite .
such protocols are called quantum energy teleportation ( qet ) and are based on ground - state entanglement of many - body quantum systems including spin chains @xcite , cold trapped ions @xcite and quantum fields @xcite . by performing a local measurement on a subsystem a of a many - body system in the ground state , information about the quantum fluctuation of a can be extracted . because the post - measurement state is not the ground state in general , some amount of energy is infused into a as qet energy input during this measurement , and the ground - state entanglement gets partially broken ..
Please generate the next two sentences of the article | next , the measurement result is announced to another subsystem b of the many - body system at a speed much faster than the diffusion velocity of the energy infused by the measurement . soon after the information arrives at b
, energy can be extracted from b as qet energy output by performing a local operation on b dependent on the announced measurement data . |
4,003 | Suppose that you have an abstract for a scientific paper: we define discrete flat surfaces in hyperbolic @xmath0-space @xmath1 from the perspective of discrete integrable systems and prove properties that justify the definition .
we show how these surfaces correspond to previously defined discrete constant mean curvature @xmath2 surfaces in @xmath1 , and we also describe discrete focal surfaces ( discrete caustics ) that can be used to define singularities on discrete flat surfaces . along the way
, we also examine discrete linear weingarten surfaces of bryant type in @xmath1 , and consider an example of a discrete flat surface related to the airy equation that exhibits swallowtail singularities and a stokes phenomenon . .
And you have already written the first three sentences of the full article: there is the classical weierstrass representation for minimal surfaces in euclidean @xmath0-space @xmath3 , which gives a local conformal parametrization for any minimal surface .
it involves choosing two holomorphic functions ( or perhaps meromorphic functions when considering the surfaces more globally ) on a riemann surface .
if one restricts to isothermic parametrizations , that is , conformal parametrizations that are also curvature lines coordinate systems , then the representation reduces to the choice of just one holomorphic function ..
Please generate the next two sentences of the article | since every minimal surface has local isothermic coordinates ( away from umbilics ) , this reduction does not involve any loss of generality beyond avoiding umbilic points .
once one restricts to isothermic parametrizations , it becomes possible to give a definition for discrete analogs of minimal surfaces @xcite . |
4,004 | Suppose that you have an abstract for a scientific paper: recent observational studies using the _ hubble space telescope ( hst ) _ have derived the center - of - mass proper motion ( cmpm ) of the large magellanic cloud ( lmc ) .
although these studies carefully treated both rotation and perspective effects in deriving the proper motion for each of the sampled fields , they did not consider the effects of local random motion in the derivation .
this means that the average pm of the fields ( i.e. , the observed cmpm ) could significantly deviate from the true cmpm , because the effect of local random motion can not be close to zero in making the average pm for the small number of the fields ( @xmath0 ) .
we discuss how significantly the observationally derived cmpm can deviate from the true cmpm by applying the same method as used in the observations for a dynamical model of the lmc with a known true cmpm .
we find that the deviation can be as large as @xmath1 km s@xmath2 ( @xmath3 mas yr@xmath2 ) , if the lmc has a thick disk and a maximum circular velocity of @xmath4 km s@xmath2 .
we also find that the deviation depends both on the total number of the sampled fields and on structure and kinematics of the lmc .
we therefore suggest that there is a possibility that the observed cmpm of the lmc deviates from the true one to some extent .
we also show that a simple mean of pm for a large number of the lmc fields ( @xmath5 ) can be much closer to the true cmpm . .
And you have already written the first three sentences of the full article: the orbital evolution of the magellanic clouds ( mcs ) with respect to the galaxy has been considered to be one of key parameters that control dynamical and chemical evolution of the lmc and the small magellanic cloud ( smc ) and the formation processes of the magellanic stream ( ms ) and its leading arms ( e.g. , murai & fujimoto 1980 , mf80 ; gardiner & noguchi 1996 , gn96 ; bekki & chiba 2005 , bc05 ; mastropietro et al . 2005 ) .
recent observational studies on the cmpm for the lmc using the high resolution camera ( hrc ) of the advanced camera for surveys ( acs ) on the @xmath6 have derived an accurate present 3d motion of the lmc around the galaxy ( e.g. , kallivayalil et al .
2006 , k06a ; piatek et al ..
Please generate the next two sentences of the article | 2008 , p08 ) .
one of remarkable results from these studies is that the lmc can possibly have a velocity with respect to the galaxy ( @xmath7 ) being @xmath8 km s@xmath2 ( kallivayalil et al . |
4,005 | Suppose that you have an abstract for a scientific paper: by applying the concept of dynamical facilitation and analyzing the excitation lines that result from this facilitation , we investigate the origin of decoupling of transport coefficients in supercooled liquids .
we illustrate our approach with two classes of models .
one depicts diffusion in a strong glass former , and the other in a fragile glass former . at low temperatures , both models exhibit violation of the stokes - einstein relation , @xmath0 , where @xmath1 is the self diffusion constant and @xmath2
is the structural relaxation time . in the strong case , the violation is sensitive to dimensionality @xmath3 , going as @xmath4 for @xmath5 , and as @xmath6 for @xmath7 . in the fragile case , however , we argue that dimensionality dependence is weak , and show that for @xmath5 , @xmath8 .
this scaling for the fragile case compares favorably with the results of a recent experimental study for a three - dimensional fragile glass former . .
And you have already written the first three sentences of the full article: normal liquids exhibit homogeneous behavior in their dynamical properties over length scales larger than the correlation length of density fluctuations .
for example , the stokes
einstein relation that relates the self diffusion constant @xmath1 , viscosity @xmath9 , and temperature @xmath10 , d , [ se ] is usually accurate @xcite ..
Please generate the next two sentences of the article | this relation is essentially a mean field result for the effects of a viscous environment on a tagged particle . in recent experimental studies
, it has been reported that the stokes |
4,006 | Suppose that you have an abstract for a scientific paper: search for @xmath0-decay of @xmath1xe with two high pressure proportional counters is carried out in baksan neutrino observatory .
the experiment is based on comparison of spectra measured with natural and enriched xenon .
the measured half life is equal to t@xmath2 yr ( 67% c.l . ) for @xmath3 decay mode .
no evidence has been found for neutrinoless @xmath0-decay .
the decay half life limit based on data measured during 17280 h is t@xmath4 yr ( 90% c.l . ) . .
And you have already written the first three sentences of the full article: the experimental investigation of the @xmath0-decay of @xmath1xe has been started more then 20 years ago . but
both two neutrino and neutrinoless modes of this process for @xmath1xe was not observed .
the results of last experiments are presented in table [ tab1 ] ..
Please generate the next two sentences of the article | the theoretical estimations of half lifetime for @xmath3-decay are presented in table [ tab2 ] .
it is necessary to mention that in @xcite only one spectrum ( measured with enriched @xmath1xe ) was obtained . to calculate their limit |
4,007 | Suppose that you have an abstract for a scientific paper: in this paper , we develop a bernstein dual - petrov - galerkin method for the numerical simulation of two - dimensional subdiffusion equation .
the equation is first discretized in time using the l1 approximation .
then , a spectral discretization is applied by introducing suitable combinations of dual bernstein polynomials as the test functions and the bernstein polynomials as the trial ones .
we derive the exact sparse operational matrix of differentiation for the dual bernstein basis which provides a matrix based approach for the spatial discretization .
it is also shown that the proposed method leads to banded linear systems that can be solved efficiently .
finally , the stability and convergence of the proposed method is discussed theoretically .
some numerical examples are provided to support the theoretical claims and to show the accuracy and efficiency of the method . .
And you have already written the first three sentences of the full article: bernstein polynomial basis plays an important role in computer graphics for geometric modeling , curve and surface approximation .
some interesting features have been investigated for this basis in the last decades ; for instance , it is proven to be an optimal stable basis among nonnegative bases in a sense described in @xcite .
also , it provides some optimal shape preserving features @xcite ..
Please generate the next two sentences of the article | we refer to @xcite for detailed properties and applications in computer aided geometric design ( cagd ) .
bernstein basis has also been used for the numerical solution of differential , integral , integro - differential and fractional differential equations , see e.g. @xcite and the references therein . |
4,008 | Suppose that you have an abstract for a scientific paper: for the microwave equivalent of `` light shining through the wall '' ( lsw ) experiments , a sensitive microwave detector and very high electromagnetic shielding is required .
the screening attenuation between the axion generating cavity and the nearby detection cavity should be greater than 300 db , in order to improve over presently existing exclusion limits . to achieve these goals in practice , a box in a box
" concept was utilized for shielding the detection cavity , while a vector signal analyzer was used as a microwave receiver with a very narrow resolution bandwidth in the order of a few micro - hz .
this contribution will present the experimental layout and the results to date . .
And you have already written the first three sentences of the full article: the axion is a hypothetical elementary particle , which emerged originally from a proposal by peccei and quinn , intended to solve the strong cp problem @xcite in theoretical physics .
the axion is neutral , only interacts weakly with matter , has a low mass ( @xmath0 ) , spin zero , and a natural decay constant ( to 2 photons ) in the order of @xmath1 years .
the axion belongs to the family of weakly interacting sub - ev particles ( wisp ) ..
Please generate the next two sentences of the article | another wisp , closely related to the axion is the paraphoton or hidden photon .
the existence of these wisps could not be confirmed yet and all experimental efforts to date have so far produced only exclusion results . |
4,009 | Suppose that you have an abstract for a scientific paper: we discuss a charge qubit consisting of a circular array of josephson junctions .
the two - level system we consider couples the two charge states through a higher order tunneling process thus making it possible to achieve a long relaxation time . using the spin - boson hamiltonian , we estimate decoherence due to ohmic as well as @xmath0 noise . we simulate the quantum mechanical measurement process by studing
the density matrix of the qubit and a capacitively coupled single - electron transistor that measures the charge . 0.1pc .
And you have already written the first three sentences of the full article: in recent years much effort has been spent on the search for quantum two - level systems , qubits , that can be coherently controlled long enough for a sequence of controlled unitary operations to be performed on them .
the ultimate goal is to build a quantum computer out of these qubits .
proposals for qubits based on a variety of physical systems exist , each with its pros and cons . here.
Please generate the next two sentences of the article | we consider solid state charge qubits based on josephson junctions ( jj ) arrays .
these have the advantage of being relatively easy to manipulate and the prospects for large scale manufacturing are comparatively good . |
4,010 | Suppose that you have an abstract for a scientific paper: lattice distortions in which the axes are locally rotated provide an intrinsic source of frustration in anisotropic superconductors . a general framework to study this effect
is presented .
the influence of lattice defects and phonons in @xmath0 and @xmath1 layered superconductors is studied . .
And you have already written the first three sentences of the full article: in anisotropic superconductors , local rotations of the lattice modulate the order parameter .
the most striking manifestation of this effect is the influence of grain boundaries in high - t@xmath2 superconductors@xcite .
less pronounced effects are also to be expected from lattice defects such as dislocations , as they twist the lattice axes in their vicinity ..
Please generate the next two sentences of the article | transversely polarized phonons can , in principle , also couple to the superconducting order parameter through the local rotations that they induce .
if , along a given direction , there are strains which change the orientation of the lattice axes , the equilibrium order parameter must follow that distortion . |
4,011 | Suppose that you have an abstract for a scientific paper: we study the finite - temperature transition to the @xmath0 magnetization plateau in a model of interacting @xmath1 spins with longer range interactions and strong exchange anisotropy on the geometrically frustrated shastry - sutherland lattice .
this model was shown to capture the qualitative features of the field - induced magnetization plateaus in the rare - earth tetraboride , @xmath2 .
our results show that the transition to the plateau state occurs via two successive transitions with the two - dimensional ising universality class , when the quantum exchange interactions are finite , whereas a single phase transition takes place in the purely ising limit . to better understand these behaviors , we perform monte carlo simulations of the classical generalized four - state chiral clock model and compare the phase diagrams of the two models .
finally , we estimate a parameter set that can explain the magnetization curves observed in @xmath2 .
the magnetic properties and critical behavior of the finite - temperature transition to the @xmath0 plateau state are also discussed . .
And you have already written the first three sentences of the full article: geometrically frustrated interactions and quantum fluctuation inhibit the stabilization of classical orderings . they sometimes become a trigger for the emergence of several exotic orders such as , quantum spin ice on the pyrochlore lattice@xcite , spin liquid state on the honeycomb lattice@xcite , and multiple magnetization plateaus@xcite . therefore ,
quantum spin systems with frustrated interactions have attracted great interest from both theoretical and experimental approaches . the @xmath1 antiferromagnetic heisenberg spin model on the shastry - sutherland lattice ( ssl)@xcite is one of such systems . the hamiltonian can be expressed by the nearest neighbor ( intradimer ) @xmath3 and the next nearest neighbor ( interdimer ) @xmath4 couplings : @xmath5
experimentally , @xmath6@xcite has been studied extensively for its realization of the model . in this compound ,.
Please generate the next two sentences of the article | @xmath7 layers stack along the @xmath8-axis direction and each magnetic layer consists of @xmath9 ions carrying @xmath1 spins arranged in an orthogonal dimer structure that is topologically equivalent to the ssl . from several experimental observations ,
it was confirmed that the field dependence of the magnetization exhibits multiple magnetization plateaus . in these magnetization plateau states , wigner crystals of spin - triplet dimers@xcite are realized reflecting the strong competition between the kinetic energy gain and mutual repulsion of the dimers . |
4,012 | Suppose that you have an abstract for a scientific paper: this is a sequel to our previous work on lhc phenomenology of the type ii seesaw model in the nondegenerate case . in this work
, we further study the pair and associated production of the neutral scalars @xmath0 .
we restrict ourselves to the so - called negative scenario characterized by the mass order @xmath1 , in which the @xmath0 production receives significant enhancement from cascade decays of the charged scalars @xmath2 .
we consider three important signal channels@xmath3 , @xmath4 , @xmath5and perform detailed simulations .
we find that at the 14 tev lhc with an integrated luminosity of @xmath6 , a @xmath7 mass reach of @xmath8 , @xmath9 , and @xmath10 , respectively , is possible in the three channels from the pure drell - yan @xmath11 production , while the cascade - decay - enhanced @xmath0 production can push the mass limit further to @xmath12 , @xmath13 , and @xmath14 .
the neutral scalars in the negative scenario are thus accessible at lhc run ii . .
And you have already written the first three sentences of the full article: in a previous paper @xcite , we presented a comprehensive analysis on the lhc signatures of the type ii seesaw model of neutrino masses in the nondegenerate case of the triplet scalars . in this companion paper , another important signature the pair and associated production of the neutral scalars
is explored in great detail .
this is correlated to the pair production of the standard model ( sm ) higgs boson , @xmath15 , which has attracted lots of theoretical and experimental interest @xcite since its discovery @xcite , because the pair production can be used to gain information on the electroweak symmetry breaking sector @xcite ..
Please generate the next two sentences of the article | since any new ingredients in the scalar sector can potentially alter the production and decay properties of the higgs boson , a thorough examination of the properties offers a diagnostic tool to physics effects beyond the sm .
the higgs boson pair production has been well studied for collider phenomenology in the framework of the sm and beyond @xcite , and extensively studied in various new physics models @xcite , as well as in the effective field theory approach of anomalous couplings @xcite and effective operators @xcite . |
4,013 | Suppose that you have an abstract for a scientific paper: the possibility of the magnetic monopole decay in the constant electric field is investigated and the exponential factor in the probability is obtained . corrections due to coulomb interaction are calculated . the relation between masses of particles for the process to exist
is obtained .
itep - th-54/05 1 cm a.k .
monin _ institute of theoretical and experimental physics , + b.cheremushkinskaya 25 , moscow , russia _ _
moscow state university , physics department , + vorobyevy gory 1 , moscow , russia _ e - mail : [email protected] 1.3 cm .
And you have already written the first three sentences of the full article: tunneling processes are very interesting nonperturbative phenomena .
one can find the example of such process already in quantum mechanics , where it causes the energy splitting .
there are tunneling processes in the field theory as well , for instance , pair production in external electromagnetic fields @xcite , decay of the false vacuum @xcite . in some spontaneously broken gauge theories.
Please generate the next two sentences of the article | there are magnetic monopole and dyon solutions .
it is supposed that they can be produced in strong enough external electromagnetic fields . in the weak coupling regime |
4,014 | Suppose that you have an abstract for a scientific paper: in this article we consider a bayesian inverse problem associated to elliptic partial differential equations ( pdes ) in two and three dimensions .
this class of inverse problems is important in applications such as hydrology , but the complexity of the link function between unknown field and measurements can make it difficult to draw inference from the associated posterior . we prove that for this inverse problem a basic smc method has a monte carlo rate of convergence with constants which are independent of the dimension of the discretization of the problem ; indeed convergence of the smc method is established in a function space setting .
we also develop an enhancement of the sequential monte carlo ( smc ) methods for inverse problems which were introduced in @xcite ; the enhancement is designed to deal with the additional complexity of this elliptic inverse problem . the efficacy of the methodology , and its desirable theoretical properties , are demonstrated on numerical examples in both two and three dimensions . + * keywords * : inverse problems , elliptic pdes , groundwater flow , adaptive smc , markov chain monte carlo . * sequential monte carlo methods for bayesian elliptic inverse problems * by alexandros beskos@xmath0 , ajay jasra@xmath1 , ege a. muzaffer@xmath1 & andrew m. stuart@xmath2 @xmath0department of statistical science , university college london , london , wc1e 7hb , uk .
+ e-mail:`[email protected] ` + @xmath1department of statistics & applied probability , national university of singapore , singapore , 117546 , sg .
+ e-mail:`[email protected] , [email protected] ` + @xmath2department of mathematics , university of warwick , coventry , cv4 7al , uk .
+ e-mail:`[email protected] ` .
And you have already written the first three sentences of the full article: the viability of the bayesian approach to inverse problems was established in the pioneering text @xcite which , in particular , demonstrated the potential for markov chain monte carlo ( mcmc ) methods in this context . nonetheless , the high dimensional nature of the unknown , often found from discretizing a field , leads to difficult problems in the design of proposals which are cheap to implement , yet which mix efficiently .
one recent approach to tackle these problems has been the development of algorithms with mesh - free mixing times , such as those highlighted in @xcite ; these non - standard mcmc algorithms avoid the unnecessary penalties incurred by naive proposals related to exploration of the part of the parameter space dominated by the prior . nonetheless , in the large dataset or small
observational noise regimes , one is still confronted with an inference problem in high dimensions which , whilst of smaller order than the dimension of the pde solver , exhibits wide variations in scales in different coordinates of the parameterizations , leading to substantial challenges for algorithmic tuning ..
Please generate the next two sentences of the article | a different approach , which we will adopt here , involves smc samplers @xcite .
these are particle methods which , in the context of bayesian inverse problems , build an approximation to a sequence of measures which interpolate from the prior to the posterior ; the sequential nature of the approximation allows for adaptation of the particle distribution and weights from the ( typically simple ) prior to the ( potentially very complex ) posterior . |
4,015 | Suppose that you have an abstract for a scientific paper: we consider a class of hamiltonians with three degrees of freedom that can be mapped into quasi - periodically driven pendulums .
the purpose of this paper is to determine the threshold of the break - up of invariant tori with a specific frequency vector .
we apply two techniques : the frequency map analysis and renormalization - group methods .
the renormalization transformation acting on a hamiltonian is a canonical change of coordinates which is a combination of a partial elimination of the irrelevant modes of the hamiltonian and a rescaling of phase space around the considered torus .
we give numerical evidence that the critical coupling at which the renormalization transformation starts to diverge is the same as the value given by the frequency map analysis for the break - up of invariant tori .
furthermore , we obtain by these methods numerical values of the threshold of the break - up of the last invariant torus
. u invariant tori , renormalization , hamiltonian systems 05.45.ac , 05.10.cc , 45.20.jj .
And you have already written the first three sentences of the full article: for hamiltonian systems , the persistence of invariant tori influences the global properties of the dynamics .
the study of the break - up of invariant tori is thus an important issue to understand the onset of chaos . for two degrees of freedom ,
there are several numerical methods to determine the threshold of the break - up of invariant tori : for instance , greene s criterion @xcite , obstruction method @xcite , converse kam @xcite , frequency map analysis @xcite , or renormalization - group methods @xcite ..
Please generate the next two sentences of the article | + in this article , we propose to compute this threshold for a one - parameter family of hamiltonians with three degrees of freedom and for a specific frequency vector , by two techniques : by frequency map analysis and by renormalization .
the frequency map analysis is valid for any dimension , and has been applied to systems with a large number of degrees of freedom @xcite . |
4,016 | Suppose that you have an abstract for a scientific paper: in a typical range emptiness searching ( resp . , reporting ) problem , we are given a set @xmath0 of @xmath1 points in @xmath2 , and wish to preprocess it into a data structure that supports efficient range emptiness ( resp .
, reporting ) queries , in which we specify a range @xmath3 , which , in general , is a semi - algebraic set in @xmath2 of constant description complexity , and wish to determine whether @xmath4 , or to report all the points in @xmath5 .
range emptiness searching and reporting arise in many applications , and have been treated by matouek @xcite in the special case where the ranges are halfspaces bounded by hyperplanes . as shown in @xcite ,
the two problems are closely related , and have solutions ( for the case of halfspaces ) with similar performance bounds . in this paper
we extend the analysis to general semi - algebraic ranges , and show how to adapt matouek s technique , without the need to _ linearize _ the ranges into a higher - dimensional space .
this yields more efficient solutions to several useful problems , and we demonstrate the new technique in four applications , with the following results : \(i ) an algorithm for ray shooting amid balls in @xmath6 , which uses @xmath7 storage and @xmath8 preprocessing , to mean an upper bound of the form @xmath9 , which holds for any @xmath10 , where @xmath11 is a constant that depends on @xmath12 . ] and answers a query in @xmath13 time , improving the previous bound of @xmath14 .
\(ii ) an algorithm that preprocesses , in @xmath8 time , a set @xmath0 of @xmath1 points in @xmath6 into a data structure with @xmath7 storage , so that , for any query line @xmath15 ( or , for that matter , any simply - shaped convex set ) , the point of @xmath0 farthest from @xmath15 can be computed in @xmath16 time . this in turn yields an algorithm that computes the largest - area triangle spanned by @xmath0 in time @xmath17 , as well as nontrivial algorithms for computing the largest - perimeter or largest - height triangle spanned....
And you have already written the first three sentences of the full article: the main technical contribution of this paper is an extension of matouek s range emptiness and reporting data structures @xcite ( see also @xcite for a dynamic version of the problem ) to the case of general semi - algebraic ranges . [ [ ray - shooting - amid - balls . ] ] ray shooting amid balls .
+ + + + + + + + + + + + + + + + + + + + + + + + a motivating application of this study is ray shooting amid balls in @xmath6 , where we want to construct a data structure of linear size with near - linear preprocessing , which supports ray shooting queries in sublinear time .
typically , in problems of this sort , the bound on the query time is some fractional power of @xmath1 , the number of objects , and the goal is to make the exponent as small as possible . for example ,.
Please generate the next two sentences of the article | ray shooting amid a collection of @xmath1 arbitrary triangles can be performed in @xmath14 time ( with linear storage ) @xcite .
better solutions are known for various special cases . |
4,017 | Suppose that you have an abstract for a scientific paper: we report on a correlation between virial mass @xmath0 and spin parameter @xmath1 for dark matter halos forming at redshifts @xmath2 .
we find that the spin parameter decreases with increasing halo mass .
interestingly , our analysis indicates that halos forming at later times do not exhibit such a strong correlation , in agreement with the findings of previous studies .
we briefly discuss the implications of this correlation for galaxy formation at high redshifts and the galaxy population we observe today . .
And you have already written the first three sentences of the full article: the physical mechanism by which galaxies acquire their angular momentum is an important problem that has been the subject of investigation for nearly sixty years ( hoyle 1949 ) .
this reflects the fundamental role played by angular momentum of galactic material in defining the size and shapes of galaxies ( e.g. fall & efstathiou 1981 ) . yet despite its physical significance , a precise and accurate understanding of the origin of galactic angular momentum remains one of the missing pieces in the galaxy formation puzzle .
a fundamental assumption in current galaxy formation models is that galaxies form when gas cools and condenses within the potential wells of dark matter halos ( white & rees 1978 ) ..
Please generate the next two sentences of the article | consequently it is probable that the angular momentum of the galaxy will be linked to the angular momentum of its dark matter halo ( e.g. fall & efstathiou 1980 ; mo , mao & white 1998 ; zavala , okamoto & frenk 2007 ) . within the context of hierarchical structure formation models , the angular momentum growth of a dark matter proto - halo
is driven by gravitational tidal torquing during the early stages ( i.e. the linear regime ) of its assembly . |
4,018 | Suppose that you have an abstract for a scientific paper: in this note a study of hadronic event shapes in qcd events at the large hadron collider ( lhc ) is presented .
calorimetric jet momenta , determined by various jet clustering algorithms , are used as input for calculating various event - shape variables which probe the structure of the hadronic final state .
it is shown that the normalized event - shape distributions are robust under variations of the jet energy scale and resolution effects , which makes them particularly suitable for early data analysis and tuning of monte carlo models . .
And you have already written the first three sentences of the full article: event shapes belong to the most widely used variables to study qcd dynamics , especially at @xmath0 and @xmath1 colliders .
event - shape observables are defined in terms of the four - momenta of jets in the final state . recently a large set of new hadronic event - shape variables has been proposed in ref .
an important aspect of these variables is their normalization to the total transverse momentum or energy in the event ..
Please generate the next two sentences of the article | therefore it is anticipated that energy scale uncertainties should cancel out to a large extent .
thus we believe that they represent an useful tool for very early measurements of the properties of qcd events at lhc and the tuning of monte carlo models . |
4,019 | Suppose that you have an abstract for a scientific paper: a web - based interface dedicated for cluster computer which is publicly accessible for free is introduced .
the interface plays an important role to enable secure public access , while providing user - friendly computational environment for end - users and easy maintainance for administrators as well . the whole architecture which integrates both aspects of hardware and software
is briefly explained .
it is argued that the public cluster is globally a unique approach , and could be a new kind of e - learning system especially for parallel programming communities . .
And you have already written the first three sentences of the full article: lipi public cluster ( lpc ) is a cluster - based computing facility maintained by lembaga ilmu pengetahuan indonesia - lipi ( the indonesian institute of sciences ) @xcite .
although it is still a small scale cluster in the sense of number of nodes already installed , it has unique characteristics among existing clusters around the globe due to its openness . here
`` open '' means everyone can access and use it anonymously for free to execute any types of parallel programmings @xcite ..
Please generate the next two sentences of the article | the development of lpc was initially motivated by real needs for high performance and advanced computing , especially in the research field of basic natural sciences . even in indonesia
, the needs are growing along with the advances of scientific researches . in the last decades , clustering low specs ( and low cost ) machines becomes popular to realize an advanced computing system comparable to , or in most cases better than the conventional mainframe - based system with significant cost reduction @xcite . |
4,020 | Suppose that you have an abstract for a scientific paper: we compute the power radiated per unit solid angle of a moving magnetic dipole moment , and its instantaneous radiated power , both non - relativistically and relativistically .
this is then applied to various interesting situations : solar neutrons , electron synchrotrons and cosmological dirac neutrinos .
concerning the latter , we show that hypothesized early - universe big bang conditions allow for neutrino radiation cooling and provide an energy loss - mechanism for subsequent neutrino condensation .
instantaneous power radiated from magnetic dipole moments p.d .
morley + system of systems analytics , inc .
+ 11250 waples mill road + suite 300 + fairfax , va 22030 - 7400 + and + d.j .
buettner + aerospace corporation + p. o. box 92957 + los angeles , ca 90009 - 2957 keywords : neutrinos , dipole radiation , condensation .
And you have already written the first three sentences of the full article: the total instantaneous radiated power@xcite of a particle carrying charge q is the larmor formula for non - relativistic motion @xmath0 and the linard formula for relativistic motion @xmath1\ ] ] in this paper , we use gaussian units with @xmath2 the speed of light , @xmath3 the usual lorentz factor @xmath4 , dots @xmath5 signifying time - derivatives and @xmath6 , where @xmath7 is the particle s velocity .
also , the neutrinos considered here are dirac neutrinos with magnetic dipole moments @xmath8 . in this paper , @xmath9 will always denote rest frame magnetic moments . using the same convention as @xcite
, the electromagnetic field notation will be : unprimed quantities such as @xmath10 denotes laboratory quantities ( here a laboratory magnetic field ) and the @xmath11 , such as @xmath12 , denotes rest frame quantities ( here a rest frame magnetic field ) ..
Please generate the next two sentences of the article | we will find that the corresponding formulae for radiation power losses of magnetic dipoles are much more complicated than eq(1,2 ) of charged particles because @xmath13 @xmath14 in the early universe , once cosmological neutrinos decouple from matter , conventional wisdom posits that they would then lose energy adiabatically from the cosmic expansion @xcite .
however , neutrinos will still interact with early - universe magnetic fields @xmath10 . |
4,021 | Suppose that you have an abstract for a scientific paper: we have conducted a systematic study of x - ray emission from ultra - compact dwarf ( ucd ) galaxies and extended star clusters ( escs ) , based on archival _ chandra _ observations . among a sample of 511 ucds and escs complied from the literature ,
17 x - ray counterparts with 0.5 - 8 kev luminosities above @xmath0@xmath1 are identified , which are distributed in eight early - type host galaxies . to facilitate comparison
, we also identify x - ray counterparts of 360 globular clusters ( gcs ) distributed in four of the eight galaxies .
the x - ray properties of the ucds and escs are found to be broadly similar to those of the gcs .
the incidence rate of x - ray - detected ucds and escs , @xmath2% , while lower than that of the x - ray - detected gcs [ ( @xmath3% ] , is substantially higher than expected from the field populations of external galaxies . a stacking analysis of the individually undetected ucds / escs further reveals significant x - ray signals , which corresponds to an equivalent 0.5 - 8 kev luminosity of @xmath0@xmath4 per source . taken together ,
these provide strong evidence that the x - ray emission from ucds and escs is dominated by low - mass x - ray binaries having formed from stellar dynamical interactions , consistent with the stellar populations in these dense systems being predominantly old . for the most massive ucds
, there remains the possibility that a putative central massive black hole gives rise to the observed x - ray emission . .
And you have already written the first three sentences of the full article: the advent of high - resolution optical imaging and follow - up spectroscopic surveys in the past two decades , has led to the recognition of a morphologically distinct class of stellar assemblies in and around external galaxies , the first few cases of which were found in the fornax cluster @xcite . these so - called ultra - compact dwarfs ( ucds ; @xcite ) manifest themselves as compact objects with typical effective radii of 10 @xmath5 pc and absolute v - band magnitudes of -14 @xmath6 -9mag , just intermediate between the classical globular clusters ( gcs ) and dwarf elliptical galaxies .
when spectroscopic information is available , ucds appear to harbor a predominantly old stellar population ( e.g. , @xcite ; janz et al .
2016 ) , in some cases with an extended star formation history ( e.g. , @xcite ) ..
Please generate the next two sentences of the article | candidate ucds are now routinely found in dense environments such as galaxy clusters ( e.g. , fornax , @xcite ; virgo , @xcite ; centaurus , @xcite ; coma , @xcite ; perseus , @xcite ) and galaxy groups ( e.g. , hcg22 and hcg90 , @xcite ) , but also in relatively isolated galaxies such as the sombrero (= m104 ; @xcite ) , ngc3923 and ngc4546 @xcite .
the nature of ucds , however , is far less clear than their names might have indicated . |
4,022 | Suppose that you have an abstract for a scientific paper: quotient is a basic operation of formal languages , which plays a key role in the construction of minimal deterministic finite automata ( dfa ) and the universal automata . in this paper
, we extend this operation to formal power series and systemically investigate its implications in the study of weighted automata . in particular , we define two quotient operations for formal power series that coincide when calculated by a word .
we term the first operation as ( left or right ) _ quotient _ , and the second as ( left or right ) _ residual_. to support the definitions of quotients and residuals , the underlying semiring is restricted to complete semirings or complete c - semirings .
algebraical properties that are similar to the classical case are obtained in the formal power series case .
moreover , we show closure properties , under quotients and residuals , of regular series and weighted context - free series are similar as in formal languages . using these operations ,
we define for each formal power series @xmath0 two weighted automata @xmath1 and @xmath2 .
both weighted automata accepts @xmath0 , and @xmath1 is the minimal deterministic weighted automaton of @xmath0 .
the universality of @xmath2 is justified and , in particular , we show that @xmath1 is a sub - automaton of @xmath2 .
last but not least , an effective method to construct the universal automaton is also presented in this paper . formal power series ; weighted automaton ; complete c - semiring ; quotient ; residual ; universal automaton ; factorization .
And you have already written the first three sentences of the full article: in formal language theory , quotient is a basic and very important operation and plays a fundamental role in the construction of minimal deterministic finite automata ( dfa ) . given a formal language @xmath3 over an alphabet @xmath4 , the left quotient @xmath5 of @xmath3 by a word @xmath6 is defined as the language @xmath7 , where @xmath8 is the free monoid of words over @xmath4 .
the famous myhill - nerode theorem then states that @xmath3 is a regular language if and only if the number of different left quotients of @xmath3 ( also called the quotient complexity @xcite of @xmath3 ) is finite .
moreover , a minimal dfa which recognizes @xmath3 can be constructed in a natural way by using left quotients as states ..
Please generate the next two sentences of the article | in particular , this means that the quotient complexity of @xmath3 is equal to the size of the minimal dfa which recognizes @xmath3 . the notion of left quotient of a formal language by a word can be extended to quotients by a formal language in two ways . given two formal languages @xmath9 , the left quotient of @xmath3 by @xmath10 , denoted by @xmath11 , is defined as the union of @xmath5 for all words @xmath6 in @xmath10 .
another extension is less well - known , if not undefined at all . |
4,023 | Suppose that you have an abstract for a scientific paper: employing strong electrostatic gating ( liquid - ion gating ) , the position of the fermi energy @xmath0 ( relative to the charge - neutrality point ) was determined in multi - wall carbon nanotubes ( mwnts ) .
@xmath0 is negative ( hole doping ) and amounts to for mwnts in air .
evidence that water , and not oxygen , is the main source of doping has been found . as a consequence ,
the number @xmath1 of occupied @xmath2d - modes ( not counting spin ) is @xmath3 , i.e. .
this is supported by the single - electron level spacing , deduced from observed single - electron charging effects ( set ) at low temperature .
the latter are dominated by co - tunneling processes , as we observe the kondo effect .
this provides evidence , that highly transmissive channels are present in mwnts at low temperature , despite the ` disorder ' observed in previous experiments . .
And you have already written the first three sentences of the full article: carbon nanotubes ( cnts ) are ideal model systems for the exploration of electrical transport in low dimensions.@xcite two sorts of nanotubes ( nts ) exist : single - wall and multi - wall nts .
an ideal ( undoped ) swnt can be either metallic or semiconducting , but here , we only focus on metallic nts . in these tubes ,
the current is carried by two modes , modes , spin - degeneracy is not included . ].
Please generate the next two sentences of the article | leading to a conductance of @xmath4 , provided backscattering is absent .
recent experiments have shown that scattering within metallic swnt is weak . in a particular nice experiment |
4,024 | Suppose that you have an abstract for a scientific paper: we take advantage of the rich multi - wavelength data available in the chandra deep field south ( cdf - s ) , including the 4 msec chandra observations ( the deepest x - ray data to date ) , in order to search for heavily - obscured low - luminosity agn among infrared - luminous galaxies .
in particular , we obtained a stacked rest - frame x - ray spectrum for samples of galaxies binned in terms of their ir luminosity or stellar mass .
we detect a significant signal at e@xmath01 to 8 kev , which we interpret as originating from a combination of emission associated with star - formation processes at low energies combined with a heavily - obscured agn at e@xmath15 kev .
we further find that the relative strength of this agn signal decays with decreasing ir luminosity , indicating a higher agn fraction for more luminous ir sources .
together , these results strongly suggest the presence of a large number of obscured agn in ir - luminous galaxies . using samples binned in terms of stellar mass in the host galaxy , we find a significant excess at e=6 - 7 kev for sources with m@xmath110@xmath2m@xmath3 , consistent with a large obscured agn population in high mass galaxies .
in contrast , no strong evidence of agn activity was found for less - massive galaxies .
the integrated intensity at high energies indicates that a significant fraction of the total black hole growth , @xmath022% , occurs in heavily - obscured systems that are not individually detected in even the deepest x - ray observations .
there are also indications that the number of low - luminosity , heavily - obscured agn does not evolve significantly with redshift , in contrast to the strong evolution seen in higher luminosity sources . .
And you have already written the first three sentences of the full article: most of the accretion onto the supermassive black hole ( smbh ) found in the center of most massive galaxies is heavily obscured by the surrounding dust and gas ( e.g. , @xcite ) . in the local universe , @xmath075% of the seyfert 2
galaxies are heavily - obscured ( @xmath4@xmath110@xmath5 @xmath6 ; @xcite ) .
many of these , if at @xmath7@xmath81 , where most of the black hole growth occurs , would not be identified in x - rays even in very deep ( @xmath11 msec ) chandra or xmm / newton exposures @xcite ..
Please generate the next two sentences of the article | locating and quantifying this heavily obscured smbh growth , in particular at high redshifts , is currently one of the fundamental problems in astrophysics .
because the energy absorbed at optical to x - ray wavelengths is later re - emitted in the mid - ir , it is expected that all active galactic nuclei ( agn ) , even the most obscured ones , should be very bright mid - ir sources ( e.g. , @xcite ) . |
4,025 | Suppose that you have an abstract for a scientific paper: an algebraic procedure to find extremal density matrices for any hamiltonian of a qudit system is established .
the extremal density matrices for pure states provide a complete description of the system , that is , the energy spectra of the hamiltonian and their corresponding projectors . for extremal density matrices representing mixed states ,
one gets mean values of the energy in between the maximum and minimum energies associated to the pure case .
these extremal densities give also the corresponding mixture of eigenstates that yields the corresponding mean value of the energy .
we enhance that the method can be extended to any hermitian operator . .
And you have already written the first three sentences of the full article: the density matrix approach was introduced to describe statistical concepts in quantum mechanics by landau @xcite , dirac @xcite , and von neumann @xcite . in several branches of physics like polarized spin assemblies or qudit systems , and cavity electrodynamics
the density matrix approach can be cast into a su(d ) description @xcite .
the bloch vector parametrization was used to describe the 2-level problem which later on was generalized to describe beams of particles with spin @xmath0 in terms of what are known as fano statistical tensors @xcite . in particular @xmath1 projectors defining the generators of a unitary algebra.
Please generate the next two sentences of the article | have been introduced in @xcite to expand a density matrix of spin systems , even more , they established a procedure to reconstruct the density matrix by a finite number of magnetic dipole measurements with stern - gerlach analyzers and concluded that it was necessary to do at least @xmath2 measurements to reconstruct the density matrix of pure states while @xmath3 were required for mixed states @xcite . an experimental reconstruction of a cavity state for @xmath4 using this method is given in @xcite .
another approach uses the moore - penrose pseudoinverse to express the elements of the spin density matrix in terms of @xmath5 probabilities of spin projections @xcite . a method to reconstruct any pure state of spin in terms of coherent states |
4,026 | Suppose that you have an abstract for a scientific paper: we present a novel algorithm for calculating the discrete fractional hadamard transform for data vectors whose size @xmath0 is a power of two .
a direct method for calculation of the discrete fractional hadamard transform requires @xmath1 multiplications , while in proposed algorithm the number of real multiplications is reduced to @xmath0log@xmath2 .
example.eps gsave newpath 20 20 moveto 20 220 lineto 220 220 lineto 220 20 lineto closepath 2 setlinewidth gsave .4 setgray fill grestore stroke grestore .
And you have already written the first three sentences of the full article: discrete fractional transforms are the generalizations of the ordinary discrete transforms with one additional fractional parameter . in the past decades ,
various discrete fractional transforms including discrete fourier transform @xcite , @xcite , discrete fractional hartley transform @xcite , discrete fractional cosine transforms and discrete sine transform @xcite have been introduced and found wide applications in many scientific and technological areas including digital signal processing @xcite , image encryption @xcite , @xcite , @xcite and digital watermarking @xcite and others .
different fast algorithms for their implementations have been separately developed to minimize computational complexity and implementation costs . in @xcite.
Please generate the next two sentences of the article | a discrete fractional hadamard transform for the vector of length @xmath3 was introduced , however a fast algorithm for the realization of this transform has not been proposed . in our previous paper @xcite
we describe a rationalized algorithm for dfrht possessing a reduced number of multiplications and additions . |
4,027 | Suppose that you have an abstract for a scientific paper: this paper studies the multi - agent average consensus problem under the requirement of differential privacy of the agents initial states against an adversary that has access to all the messages .
we first establish that a differentially private consensus algorithm can not guarantee convergence of the agents states to the exact average in distribution , which in turn implies the same impossibility for other stronger notions of convergence .
this result motivates our design of a novel differentially private laplacian consensus algorithm in which agents linearly perturb their state - transition and message - generating functions with exponentially decaying laplace noise .
we prove that our algorithm converges almost surely to an unbiased estimate of the average of agents initial states , compute the exponential mean - square rate of convergence , and formally characterize its differential privacy properties .
we show that the optimal choice of our design parameters ( with respect to the variance of the convergence point around the exact average ) corresponds to a one - shot perturbation of initial states and compare our design with various counterparts from the literature .
simulations illustrate our results .
average consensus , differential privacy , multi - agent systems , exponential mean - square convergence rate , networked control systems .
And you have already written the first three sentences of the full article: the social adoption of new technologies in networked cyberphysical systems relies heavily on the privacy preservation of individual information .
social networking , the power grid , and smart transportation are only but a few examples of domains in need of privacy - aware design of control and coordination strategies . in these scenarios ,
the ability of a networked system to fuse information , compute common estimates of unknown quantities , and agree on a common view of the world is critical . motivated by these observations , this paper studies the multi - agent average consensus problem , where a group of agents seek to agree on the average of their individual values by only interchanging information with their neighbors ..
Please generate the next two sentences of the article | this problem has numerous applications in synchronization , network management , and distributed control / computation / optimization . in the context of privacy preservation , the notion of differential privacy has gained significant popularity due to its rigorous formulation and proven security properties , including resilience to post - processing and side information , and independence from the model of the adversary . roughly speaking ,
a strategy is differentially private if the information of an agent has no significant effect on the aggregate output of the algorithm , and hence its data can not be inferred by an adversary from its execution . |
4,028 | Suppose that you have an abstract for a scientific paper: the detection and study of extrasolar planets is an exciting and thriving field in modern astrophysics , and an increasingly popular topic in introductory astronomy courses .
one detection method relies on searching for stars whose light has been gravitationally microlensed by an extrasolar planet . in order to facilitate instructors abilities to bring this interesting mix of general relativity and extrasolar planet detection into the introductory astronomy classroom
, we have developed a new _ lecture - tutorial _
, detecting exoplanets with gravitational microlensing . " in this paper
, we describe how this new _ lecture - tutorial _
s representations of astrophysical phenomena , which we selected and created based on theoretically motivated considerations of their pedagogical affordances , are used to help introductory astronomy students develop more expert - like reasoning abilities . .
And you have already written the first three sentences of the full article: an incredible amount of our advances in understanding the universe over the past 100 years can be traced back to einstein s groundbreaking 1915 paper on general relativity .
general relativity is used to understand the precession of mercury s perihelion , the orbital decay of binary pulsars , and the expansion and evolution of the universe from the time of the big bang , among many other phenomena .
one of the most important uses of general relativity in observational astronomy is its ability to accurately describe how a massive object can act as a gravitational lens , bending and magnifying the light from a source located elsewhere in the universe ..
Please generate the next two sentences of the article | while gravitational lensing is studied on the largest scales ( e.g. , galaxy clusters act as gravitational lenses for galaxies at higher redshifts ) , it also has observable effects at smaller scales , where gravitational lensing effects are used to detect the existence of extrasolar planets.@xcite this planet detection method relies on the fact that the light from a distant star may be lensed by objects in a closer stellar system .
depending on the relative alignment of earth , the distant star , and the closer stellar system , the light from the distant star may be lensed by a planet , star , or both in the stellar system . in all cases , |
4,029 | Suppose that you have an abstract for a scientific paper: continued photometric monitoring of the gravitational lens system 0957 + 561a , b in the @xmath0 and @xmath1 bands with the apache point observatory ( apo ) 3.5 m telescope during 1996 shows a sharp @xmath0 band event in the trailing ( b ) image light curve at the precise time predicted in an earlier paper .
the prediction was based on the observation of the event during 1995 in the leading ( a ) image and on a differential time delay of 415 days .
this success confirms the so called `` short delay '' , and the absence of any such feature at a delay near 540 days rejects the `` long delay '' for this system , thus resolving a long standing controversy .
a series of statistical analyses of our light curve data yield a best fit delay of @xmath2 days ( 95% confidence interval ) and demonstrate that this result is quite robust against variations in the analysis technique , data subsamples and assumed parametric relationship of the two light curves .
recent improvements in the modeling of the lens system ( consisting of a galaxy plus a galaxy cluster ) allow us to derive a value of the global ( at @xmath3 ) value of hubble s constant @xmath4 using refsdal s method , a simple and direct ( single step ) distance determination based on experimentally verified and securely understood physics and geometry .
the result is @xmath5 km / s / mpc ( for @xmath6 ) where this 95% confidence interval is dominantly due to remaining lens model uncertainties .
however , it is reassuring that available observations of the lensing mass distribution over constrain the model and thus provide an internal consistency check on its validity . _
we argue that this determination of the extragalactic distance scale ( 10% accurate at 1@xmath7 ) is now of comparable quality , in terms of both statistical and systematic uncertainties , to those based on more conventional techniques .
_ finally , we briefly discuss the prospects for improved @xmath4 determinations using gravitational lenses and some other possible....
And you have already written the first three sentences of the full article: more than 30 years ago , refsdal ( 1964 , 1966 ) pointed out that the differential light propagation time delay between two or more gravitationally lensed images of a background object establishes an absolute physical distance scale ( @xmath8 ) in the system .
thus , the distance to a high - redshift object is directly measured , yielding a value of hubble s constant , @xmath4 .
the theory of this technique has been elaborately developed and its realization has become a major focus of gravitational lens studies [ narayan ( 1991 ) gives an especially elegant treatment ; see blandford & narayan ( 1992 ) and narayan & bartelmann ( 1996 ) for reviews ] ..
Please generate the next two sentences of the article | it may be useful to briefly review the main strengths of the lensing method in determination of the extragalactic distance scale : 1 .
it is a geometrical method based on the well understood and experimentally verified physics of general relativity in the weak - field limit . |
4,030 | Suppose that you have an abstract for a scientific paper: we investigate differences between a simple dominance principle applied to sums of _ fair prices _ for variables and dominance applied to sums of _ forecasts _ for variables scored by proper scoring rules .
in particular , we consider differences when fair prices and forecasts correspond to finitely additive expectations and dominance is applied with infinitely many prices and/or forecasts . , .
And you have already written the first three sentences of the full article: the requirement that preferences are _ coherent _ aims to make rigorous the idea that elementary restrictions on rational preferences entail that personal probabilities satisfy the axioms of mathematical probability .
this use of coherence as a justification of personal probability is very well illustrated by de finetti s ( @xcite ) approach to the foundations of probability .
de finetti distinguished two senses of coherence : coherence@xmath0 and coherence@xmath1 ..
Please generate the next two sentences of the article | coherence@xmath0 requires that probabilistic forecasts for random variables ( he calls them previsions ) do not lead to a finite set of fair contracts that , together , are uniformly dominated by abstaining .
coherence@xmath1 requires that a finite set of probabilistic forecasts can not be uniformly dominated under brier ( squared error ) score by a rival set of forecasts . |
4,031 | Suppose that you have an abstract for a scientific paper: we present observations of 77 early - type galaxies imaged with the pc1 ccd of _ hst_+wfpc2 .
`` nuker law '' parametric fits to the surface brightness profiles are used to classify the central structure into `` core '' or `` power - law '' forms .
core galaxies are typically rounder than power - law galaxies .
nearly all power - laws with central ellipticity @xmath0 have stellar disks , implying that disks are present in most power - laws with @xmath1 but are not visible due to unfavorable geometry .
a few low - luminosity flattened core galaxies also have disks ; these may be transition forms from power - laws to more luminous core galaxies , which lack disks .
several core galaxies have strong isophote twists interior to their break radii , although power - laws have interior twists of similar physical significance when the photometric perturbations implied by the twists are evaluated .
central color gradients are typically consistent with the envelope gradients ; core galaxies have somewhat weaker color gradients than power - laws .
nuclei are found in 29% of the cores and 60% of the power - laws .
nuclei are typically bluer than the surrounding galaxy . while some nuclei are associated with agn , just as many are not ; conversely , not all galaxies known to have low - level agn exhibit detectable nuclei in the broad - band filters .
ngc 4073 and 4382 , are found to have central minima in their intrinsic starlight distributions ; ngc 4382 resembles the double nucleus of m31 . in general , the peak brightness location is coincident with the photocenter of the core to a typical physical scale @xmath2 pc .
five galaxies , however , have centers significantly displaced from their surrounding cores ; these may be unresolved asymmetric double nuclei .
lastly , as noted by previous authors , central dust is visible in about half of the galaxies .
the presence and strength of dust correlates with nuclear emission , thus dust may outline gas that is falling into the central black hole .....
And you have already written the first three sentences of the full article: this paper presents _ hst / wfpc2 _ observations of 77 early - type galaxies .
we investigate the central morphology of the galaxies by characterizing the properties of their nuclei , color gradients , ellipticities , isophote twists , instances of central surface brightness minima , offset centers , dust content , and dust morphologies .
the result is a more complete portrait of the sample galaxies than has been available heretofore and a reference where many different properties are measured and compared in one place ..
Please generate the next two sentences of the article | we also derive high resolution surface photometry profiles of the sample galaxies , which we characterize with `` nuker law '' fits @xcite .
analysis of the fit parameters is presented in paper vi ( lauer et al . |
4,032 | Suppose that you have an abstract for a scientific paper: if @xmath0 is a rational polygon , then the associated rational billiard table is given by @xmath1 .
such a billiard table is well understood .
if @xmath2 is a closed fractal curve approximated by a sequence of rational polygons , then the corresponding fractal billiard table is denoted by @xmath3 . in this paper
, we survey many of the results from [ * lapnie1 - 3 * ] for the koch snowflake fractal billiard @xmath4 and announce new results on two other fractal billiard tables , namely , the @xmath5-fractal billiard table @xmath6 ( see @xcite ) and a self - similar sierpinski carpet billiard table @xmath7 ( see @xcite ) . we build a general framework within which to analyze what we call a sequence of compatible orbits .
properties of particular sequences of compatible orbits are discussed for each prefractal billiard @xmath8 , @xmath9 and @xmath10 , for @xmath11 . in each case
, we are able to determine a particular limiting behavior for an appropriately formulated sequence of compatible orbits .
such a limit either constitutes what we call a nontrivial path of a fractal billiard table @xmath3 or else a periodic orbit of @xmath3 with finite period . in our examples ,
@xmath2 will be either @xmath12 , @xmath13 or @xmath14 .
several of the results and examples discussed in this paper are presented for the first time .
we then close with a brief discussion of open problems and directions for further research in the emerging field of fractal billiards . .
And you have already written the first three sentences of the full article: this paper constitutes a survey of a collection of results from @xcite as well as the announcement of new results on the @xmath5-fractal billiard table @xmath6 ( see @xcite ) and a self - similar sierpinski carpet billiard table @xmath7 ( see @xcite ) . in [ sec :
rationalbilliards ] and [ sec : fractalgeometry ] , we survey the necessary background material for understanding the remainder of the article . more specifically , in [ sec : rationalbilliards ] , we introduce the notion of a rational polygonal billiard , a translation surface determined from a rational polygonal billiard and discuss the consequence of a dynamical equivalence between the billiard flow and the geodesic flow .
this dynamical equivalence allows us to express an orbit of a rational billiard table as a geodesic on an associated translation surface , and vice - versa , with the added benefit of being able to determine the reflection in certain types of vertices of a rational billiard table ..
Please generate the next two sentences of the article | furthermore , in [ sec : fractalgeometry ] , we provide additional background material from the subject of fractal geometry necessary for understanding the construction of the koch snowflake @xmath12 , @xmath5-fractal @xmath13,-fractal @xmath13 was previously studied in a different context in @xcite . ] and a sierpinski carpet @xmath15 , as well as particular orbits and _ nontrivial paths_. we then combine the background material presented in [ sec : rationalbilliards ] and [ sec : fractalgeometry ] to analyze the prefractal billiard tables @xmath8 , @xmath9 and @xmath10 , for @xmath11 .
we begin by providing a general language for prefractal billiards and subsequently focus on determining sufficient conditions for what we are calling a _ sequence of compatible periodic orbits_. while [ subsec : theprefractalkochsnowflakebilliard][subsec : aprefractalselfsimilarsierpinskicarpetbilliard ] contain specific results and specialized definitions , there is an over - arching theme that is more fully developed in |
4,033 | Suppose that you have an abstract for a scientific paper: the morphological scaling properties of linear polymer films grown by vapor deposition polymerization ( vdp ) are studied by 1 + 1d monte carlo simulations .
the model implements the basic processes of random angle ballistic deposition ( @xmath0 ) , free - monomer diffusion ( @xmath1 ) and monomer adsorption along with the dynamical processes of polymer chain initiation , extension , and merger .
the ratio @xmath2 is found to have a strong influence on the polymer film morphology .
spatial and temporal behavior of kinetic roughening has been extensively studied using finite - length scaling and height - height correlations @xmath3 .
the scaling analysis has been performed within the no - overhang approximation and the scaling behaviors at local and global length scales were found to be very different .
the global and local scaling exponents for morphological evolution have been evaluated for varying free - monomer diffusion by growing the films at @xmath4 = @xmath5 , @xmath6 , @xmath7 , and @xmath8 and fixing the deposition flux @xmath0 . with an increase in @xmath4 from @xmath5 to @xmath8 ,
the average growth exponent @xmath9 was found to be invariant , whereas the global roughness exponent @xmath10 decreased from @xmath11 to @xmath12 along with a corresponding decrease in the global dynamic exponent @xmath13 from @xmath14 to @xmath15 .
the global scaling exponents were observed to follow the dynamic scaling hypothesis , @xmath16 . with a similar increase in @xmath4
however , the average local roughness exponent @xmath17 remained close to @xmath18 and the anomalous growth exponent @xmath19 decreased from 0.23(4 ) to 0.18(8 ) .
the interfaces display anomalous scaling and multiscaling in the relevant height - height correlations .
the variation of @xmath3 with deposition time @xmath20 indicates non - stationary growth .
a comparison has been made between the simulational findings and the experiments wherever applicable . .
And you have already written the first three sentences of the full article: our motivation for gaining theoretical understanding of polymer thin film growth stems from their technological applications in microelectronic interconnects @xcite , organic electronics @xcite , and biotechnology .
various experimental methods like vapor deposition polymerization ( vdp ) @xcite , ionization assisted polymer deposition @xcite , sputtering growth @xcite , pulsed laser deposition @xcite , and organic molecular beam deposition @xcite have been developed to produce a variety of polymer thin films .
polymer film growth is complex compared to the conventional inorganic thin film growth process due to polymer s complicated structure and interactions that include internal degrees of freedom , limited bonding sites , chain - chain interactions , etc ..
Please generate the next two sentences of the article | many experimental efforts have focussed on the formation of polymer thin films using vdp @xcite . in a typical vdp experiment ,
a wafer ( 2-d substrate ) is exposed to one or more volatile gas phase precursors that produce free - monomers . |
4,034 | Suppose that you have an abstract for a scientific paper: the f - theory vacuum constructed from an elliptic calabi yau threefold with section yields an effective six - dimensional theory .
the lie algebra of the gauge sector of this theory and its representation on the space of massless hypermultiplets are shown to be determined by the intersection theory of the homology of the calabi
yau threefold .
( similar statements hold for m - theory and the type iia string compactified on the threefold , where there is also a dependence on the expectation values of the ramond
ramond fields . )
we describe general rules for computing the hypermultiplet spectrum of any f - theory vacuum , including vacua with non - simply - laced gauge groups .
the case of monodromy acting on a curve of @xmath0 singularities is shown to be particularly interesting and leads to some unexpected rules for how @xmath1-branes are allowed to wrap certain @xmath1-cycles .
we also review the peculiar numerical predictions for the geometry of elliptic calabi
yau threefolds with section which arise from anomaly cancellation in six dimensions . 0 .
And you have already written the first three sentences of the full article: the f - theory vacuum @xcite constructed from an elliptically fibered threefold @xmath2 with section determines an effective theory with @xmath3 supersymmetry in six dimensions .
such supersymmetric theories will have fields in hypermultiplets , vector supermultiplets and tensor supermultiplets .
( see , for example , @xcite for a discussion of such theories . ) for any particular f - theory vacuum , the taxonomy of the supermultiplets may be derived from the geometry of @xmath2 as an elliptic fibration via seemingly straightforward methods in the case of the vector and tensor multiplets @xcite ..
Please generate the next two sentences of the article | the classification of the hypermultiplet content has always been a little harder to carry out .
many methods have been proposed which allow the hypermultiplets to be determined from the geometry in certain cases @xcite . |
4,035 | Suppose that you have an abstract for a scientific paper: the proper understanding of the electromagnetic counterpart of gravity - waves emitters is of serious interest to the multimessenger astronomy . in this article , we study the numerical stability of the quasinormal modes ( qnm ) and quasibound modes ( qbm ) obtained as solutions of the teukolsky angular equation and the teukolsky radial equation with appropriate boundary conditions .
we use the epsilon - method for the system featuring the confluent heun functions to study the stability of the spectra with respect to changes in the radial variable .
we find that the qnm and qbm are stable in certain regions of the complex plane , just as expected , while the third `` spurious '' spectrum was found to be numerically unstable and thus unphysical .
this analysis shows the importance of understanding the numerical results in the framework of the theory of the confluent heun functions , in order to be able to distinguish the physical spectra from the numerical artifacts . .
And you have already written the first three sentences of the full article: the quest for understanding ultra - energetic events such as gamma - ray bursts , active - galactic nuclei , quasars etc . passes through understanding of the compact massive objects which are thought to be their central engine the rotating black holes , magnetars , binary neutron stars , etc .. for this , one needs to make a clear difference between theoretical , numerical and observational black hole ( bh ) and also , to keep account of the strengths and the weaknesses of the methods numerical and observational when working with the different types of objects . in the case of black holes candidates in the role of central engines ,
the theoretical energy extraction processes of ultra - relativistic jets ( such as the penrose process or the blandford - znajek process ) should depend on the rotational bh parameter ( @xmath0 ) , with a predicted threshold for effective jet launching to be around @xmath1 , with more conservative estimate at @xmath2 @xcite .
observationally , the measured rotational parameters seem to follow this requirement a list of measured @xmath0 can be found in table 1 in @xcite . from it , one can see that in general , the measurements correspond to the expectations ..
Please generate the next two sentences of the article | there is , however , a catch .
the measurement of the spins of the black hole candidates is not independent it depends critically on the measurement of their masses , which comes with serious incertitude @xcite . |
4,036 | Suppose that you have an abstract for a scientific paper: we report hete-2 wxm / fregate observations of the x - ray flash , xrf 020903 .
this event was extremely soft : the ratio @xmath0 , where @xmath1 and @xmath2 are the fluences in the 2 - 30 and 30 - 400 kev energy bands , is the most extreme value observed so far by hete-2 .
in addition , the spectrum has an observed peak energy @xmath3 kev ( 99.7% probability upper limit ) and no photons were detected above @xmath4 10 kev .
the burst is shorter at higher energies , which is similar to the behavior of long grbs .
we consider the possibility that the burst lies at very high redshift and that the low value of @xmath5 is due to the cosmological redshift , and show that this is very unlikely .
we find that the properties of xrf 020903 are consistent with the relation between the fluences @xmath6 and @xmath7 found by barraud et al . for grbs and x - ray - rich grbs , and
are consistent with the extension by a decade of the hardness - intensity correlation ( mallozzi et al .
1995 ) found by the same authors . assuming that xrf 020903 lies at a redshift @xmath8 as implied by the host galaxy of the candidate optical and radio afterglows of this burst
, we find that the properties of xrf 020903 are consistent with an extension by a factor @xmath9 of the relation between the isotropic - equivalent energy @xmath10 and the peak @xmath11 of the @xmath12 spectrum ( in the source frame of the burst ) found by amati et al . for grbs .
the results presented in this paper therefore provide evidence that xrfs , x - ray - rich grbs , and grbs form a continuum and are a single phenomenon .
the results also impose strong constraints on models of xrfs and x - ray - rich grbs . .
And you have already written the first three sentences of the full article: gamma - ray bursts ( grbs ) that have a large fluence in the x - ray energy band ( 2 - 30 kev ) relative to the gamma - ray energy band ( 30 - 400 kev ) are receiving increased attention .
the burst and transient source experiment ( batse ) on board the _ compton gamma ray observatory _ detected 2704 grbs @xcite .
the spectra of 156 bright bursts exhibit a distribution of low - energy power - law indices @xmath13 whose centroid is @xmath14 , and a distribution of observed break energies @xmath15 whose centroid is @xmath16 230 kev @xcite , where @xmath17 ..
Please generate the next two sentences of the article | here @xmath13 , @xmath18 , and @xmath5 are the slope of the low - energy power - law index , the high - energy power - law index , and the energy of the peak of the @xmath12 spectrum of the band function @xcite , an expression that satisfactorily represents the spectra of almost all grbs . in contrast , 36% of the bright bursts observed by _
ginga _ have peak energies @xmath5 in their photon number spectrum at a few kev and large x - ray to @xmath19-ray fluence ratios @xcite . |
4,037 | Suppose that you have an abstract for a scientific paper: observations of the central radian of the galaxy by the _ reuven ramaty high energy solar spectroscopy imager ( rhessi ) have yielded a high - resolution measurement of the 1809 kev line from @xmath0al , detected at 11@xmath1 significance in nine months of data .
the _ rhessi result for the width of the cosmic line is @xmath2 kev fwhm .
the best fit line width of 5.4 kev fwhm reported by @xcite using the gamma - ray imaging spectrometer ( gris ) balloon instrument is rejected with high confidence . _ _ .
And you have already written the first three sentences of the full article: the 1809 kev line of @xmath0al was the first astronomical gamma - ray line from radioactive decay discovered in the galaxy @xcite , confirming a prediction made by @xcite and @xcite .
it is the brightest galactic line after the line from positron annihilation at 511 kev .
this first result was from _.
Please generate the next two sentences of the article | heao 3 , which used high - resolution germanium detectors .
@xcite found that the line width was consistent with their instrumental resolution of about 3 kev , but the statistical significance of the result was low ( 4.8 @xmath1 ) . _ |
4,038 | Suppose that you have an abstract for a scientific paper: we present an application of the thermal comptonization / disk reprocessing model recently proposed by zdziarski , lubiski , & smith .
we show that the absence of strong optical variations in the presence of strong concurrent x - ray variations , similar to those found by hst / rxte monitoring observations of ngc 3516 , can be explained by changing the geometry of the comptonizing plasma rather than the accretion disk itself .
the total x - ray luminosity of the comptonizing plasma must decrease as its spatial extent increases .
in contrast , the disk inner radius must be roughly fixed in order not to produce optical / ultraviolet color variations stronger than observed . by including emission due to internal viscous dissipation in the disk
, we can roughly match the optical and x - ray flux levels and variability amplitudes seen from ngc 3516 during the hst / rxte campaign . .
And you have already written the first three sentences of the full article: a ubiquitous feature of the optical / uv emission from type 1 seyfert galaxies ( sy1s ) is the highly correlated variability of the continuum flux across a wide range of wavelengths ( e.g. , peterson et al .
1998 ) . when this behavior was first observed during the 19891990 broad line region reverberation mapping campaign for ngc 5548 ( peterson et al.1991 ; clavel et al . 1991 ) , it was immediately recognized that the upper limits for the relative lags between the optical and uv wavebands were too small for the variability to have been mediated by hydrodynamic processes in the putative accretion disk the differences in the characteristic radii for the emission in the respective wavebands were too large .
in fact , the upper limits for the interband lags of @xmath0days required signal speeds of @xmath1 which could not have occurred within the disk itself ..
Please generate the next two sentences of the article | this fact and the observation that the optical / uv continuum became bluer as the flux increased led to the conclusion that the continuum variations were due to thermal reprocessing in the disk of higher energy radiation produced by a single varying source , such as the x - ray source posited to exist at the disk s inner regions , near the central black hole ( krolik et al .
1991 ; courvoisier & clavel 1991 ; collin - souffrin 1991 ) . |
4,039 | Suppose that you have an abstract for a scientific paper: the results of a comprehensive infrared imaging search for the putative @xmath0 astrometric companion to the 4.4 pc white dwarf van mannen 2 are reported .
adaptive optics images acquired at @xmath1 m reveal a diffraction limited core of @xmath2 and no direct evidence of a secondary .
models predict that at 5 gyr , a @xmath3 brown dwarf would be only 1 magnitude fainter than van maanen 2 at this wavelength and the astrometric analysis suggested a separation of @xmath4 . in the case of a chance alignment along the line of sight , a 0.4 mag excess should be measured .
an independent photometric observation at the same wavelength reveals no excess .
in addition , there exist published _ iso _
observations of van maanen 2 at @xmath5 m and @xmath6 m which are consistent with photospheric flux of a 6750 k white dwarf .
if recent brown dwarf models are correct , there is no substellar companion with @xmath7 k. .
And you have already written the first three sentences of the full article: van maanen s star , also known as van maanen 2 was discovered in 1917 by adrian van maanen @xcite .
its discovery was quite accidental , as van maanen was searching for common proper motion companions to hd4628 ( lalande 1299 ) and noticed the even larger proper motion of a nearby star . at 4.4 pc ,
van maanen 2 is the nearest single white dwarf @xcite ..
Please generate the next two sentences of the article | @xcite reported the astrometric detection of a substellar companion to van maanen 2 through analysis of _ hipparcos _ data .
the data suggested an orbital solution with a lower bound companion mass of @xmath8 , a period of 1.57 yr , and a maximum separation on the sky of @xmath9 . |
4,040 | Suppose that you have an abstract for a scientific paper: nitrogen - doped carbon nanotubes can provide reactive sites on the porphyrin - like defects .
it s well known that many porphyrins have transition metal atoms , and we have explored transition metal atoms bonded to those porphyrin - like defects in n - doped carbon nanotubes .
the electronic structure and transport are analized by means of a combination of density functional theory and recursive green s functions methods .
the results determined the heme b - like defect ( an iron atom bonded to four nitrogens ) as the most stable and with a higher polarization current for a single defect .
with randomly positioned heme b - defects in a few hundred nanometers long nanotubes the polarization reaches near 100% meaning an effective spin filter .
a disorder induced magnetoresistance effect is also observed in those long nanotubes , values as high as 20000% are calculated with non - magnectic eletrodes . since their discovery by iijima in 1991 ,
carbon nanotubes@xcite ( cnt ) have become the subject of intense research due to their potential for applications,@xcite such as in novel electronic devices.@xcite furthermore , in a seminal paper by tsukagoshi _
et al _ cnts entered the realm of spintronics , whereby one envision the possibility of using the electron spin , instead of its charge , as information carrier.@xcite in that work the authors demonstrated that the spin coherence length of polarized electrons injected onto cnts is larger than 300 nm .
thus , carbon nanotube devices could be used to manipulate spins in a coherent manner .
the prototypical spintronics device uses spin - polarized electrons , which are injected from a source into an unpolarized region and analyzed by a polarized drain . within this arrangement the so - called giant magnetoresistance effect ( gmr)@xcite manifests itself by altering - via an external magnetic field - the relative orientations of the magnetic moments of the electrodes . from a practical point of view
this setup usually involves sandwiching....
And you have already written the first three sentences of the full article: the authors would like to acknowledge fapesp , capes and cnpq for financial support .
the calculations were carried out at cce - usp , center for high performance computing at ufabc and cenapad / sp ..
Please generate the next two sentences of the article | |
4,041 | Suppose that you have an abstract for a scientific paper: in this paper @xmath0 scattering with large , but more or less equal virtualities of two photons is discussed using bfkl dynamics , emphasizing the large impact parameter behavior ( @xmath1 ) of the dipole - dipole amplitude .
it is shown that the non - perturbative contribution is essential to fulfill the unitarity constraints in the region of @xmath2 , where @xmath3 is pion mass .
the saturation and the unitarization of the dipole - dipole amplitude is considered in the framework of the glauber - mueller approach .
the main result is that we can satisfy the unitarity constraints introducing the non - perturbative corrections only in initial conditions ( born amplitude ) .
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And you have already written the first three sentences of the full article: in this paper we continue our investigation of @xmath0 scattering at high energies ( see ref.@xcite for our previous attempts to study this process in the dglap dynamics ) .
we concentrate our efforts here on the case of two photons with large but almost equal virtualities .
it has been argued @xcite that this process is the perfect tool to recover the bfkl dynamics @xcite which is the key problem in our understanding of the low @xmath7 ( high energy ) asymptotic behavior in qcd ..
Please generate the next two sentences of the article | it is well known that the correct degrees of freedom at high energy are not quarks or gluon but colour dipoles @xcite which have transverse sizes @xmath8 and the fraction of energy @xmath9 .
therefore , two photon interactions occur in two successive steps . |
4,042 | Suppose that you have an abstract for a scientific paper: the loss of ultracold trapped atoms due to deeply inelastic reactions has previously been taken into account in effective field theories for low - energy atoms by adding local anti - hermitian terms to the effective hamiltonian . here
we show that when multi - atom systems are considered , an additional modification is required in the equation governing the density matrix .
we define an effective density matrix by tracing over the states containing high - momentum atoms produced by deeply inelastic reactions .
we show that it satisfies a lindblad equation , with local lindblad operators determined by the local anti - hermitian terms in the effective hamiltonian .
we use the lindblad equation to derive the universal relation for the two - atom inelastic loss rate for fermions with two spin states and the universal relation for the three - atom inelastic loss rate for identical bosons . .
And you have already written the first three sentences of the full article: the development of technologies to trap and cool neutral atoms has led to the emergence of cold atom physics as a new subfield of atomic physics .
the atoms can be cooled to temperatures that are orders of magnitude smaller than the tiny differences between the hyperfine energy levels of the atoms .
many of the most important loss processes for ultracold atoms involve deeply inelastic reactions , which produce atoms with kinetic energies much larger than those of the cold trapped atoms ..
Please generate the next two sentences of the article | one such process is three - body recombination , in which a collision of three low - energy atoms results in the binding of two of the atoms into a diatomic molecule .
if the binding energy of the molecule is large compared to the energy scale of the cold atoms , the momenta of the molecule and the recoiling atom are often large enough for them to escape from the trapping potential for the atoms . |
4,043 | Suppose that you have an abstract for a scientific paper: we numerically study the magnetization and the dispersion relation of a frustrated quantum spin system .
our method , which is named the stochastic state selection method , is a kind of monte carlo method to give eigenstates of the system through statistical averaging processes . using the stochastic state selection method with some constraints
, we make a successful study of the spin-1/2 heisenberg antiferromagnet on a 48-site triangular lattice .
we calculate the sublattice magnetization and the static structure function in the ground state .
our result on the sublattice magnetization is consistent with the value given by the linear spin wave theory .
this adds an evidence for the analysis based on the spontaneous symmetry breaking of the semi - classical nel order in the ground state .
we also evaluate the low - lying one magnon spectra of the model with all wave vectors available on a 48-site triangular lattice .
we find that at the ordering wave vector there is a goldstone mode , which is in good agreement with the result from the spin wave analysis .
the magnon spectra with other wave vectors , however , are quite different from results obtained by the linear spin wave theory .
we observe a flat dispersion relation with a strong downward renormalization .
our results are compatible with those recently reported in the series expansion study and in the order @xmath0 calculation of the spin wave analysis . .
And you have already written the first three sentences of the full article: since the pioneering work by anderson and fazekas@xcite , the spin-1/2 heisenberg antiferromagnet on a triangular lattice has been extensively investigated as a promising candidate to realize a spin - liquid ground state induced by geometric frustration and quantum fluctuations . yet , in spite of a large amount of theoretical and experimental works , we do not have any unified picture for this system . on the theoretical side ,
most of the numerical studies carried out over the past decade with a variety of different techniques do not support that the suggested spin - liquid ground state is realized in this model .
instead they provide evidences to indicate the ground state with the three - sublattice order where the average direction of neighboring spins differs by a @xmath1 angle@xcite ..
Please generate the next two sentences of the article | then the linear spin wave theory ( lswt)@xcite well describes numerical results calculated on lattices with finite sizes . on the experimental side ,
several novel materials with triangular structures have been investigated recently . |
4,044 | Suppose that you have an abstract for a scientific paper: * abstract : * we investigate the thermodynamics of kerr - newman - kasuya black hole on the inner and outer horizons .
products of surface gravities , surface temperatures , komar energies , electromagnetic potentials , angular velocities , areas , entropies , horizon radii and the irreducible masses at the cauchy and the event horizons are calculated .
it is observed that the product of surface gravities , surface temperature product and product of komar energies , electromagnetic potentials and angular velocities at the horizons are not universal quantities for kerr - newman - kasuya black hole .
products of areas and entropies at both the horizons are independent of mass of the black hole . heat capacity is calculated and phase transition is observed , under certain conditions on @xmath0 . using the thermodynamics method with quantized charges ( known as refined thermodynamics ) , the central charges and the holographic pictures ( j - picture , q - picture , and p - picture ) of the dual cft for kerr - newman - kasuya black hole are determined . .
And you have already written the first three sentences of the full article: the most interesting objects in theoretical physics are arguably black holes . to understand their dynamics we need to put together two widely accepted theories of nature : general relativity ( einstein s classical theory of gravity ) and quantum mechanics .
black hole thermodynamics is the crossroad between the classical and the quantum pictures .
discovery of hawking radiations lead to the identification of black holes as thermodynamic objects with physical temperature and entropy @xcite ..
Please generate the next two sentences of the article | this discovery paved the way for progress in the understanding of spacetime , quantum mechanically @xcite .
variation in the mass , @xmath1 , of a rotating black hole having angular momentum , @xmath2 , and electric charge @xmath3 , obeys the formalism @xmath4known as first law of thermodynamics . here |
4,045 | Suppose that you have an abstract for a scientific paper: a chain of metallic particles , of sufficiently small diameter and spacing , allows linearly polarized plasmonic waves to propagate along the chain . in this paper
, we consider how these waves are altered by an anisotropic host ( such as a nematic liquid crystal ) or an applied magnetic field . in a liquid crystalline host , with principal axis ( director ) oriented either parallel or perpendicular to the chain , we find that the dispersion relations of both the longitudinal ( @xmath0 ) and transverse ( @xmath1 ) modes are significantly altered relative to those of an isotropic host . furthermore ,
when the director is perpendicular to the chain , the doubly degenerate @xmath1 branch is split by the anisotropy of the host material . with an applied magnetic field
@xmath2 parallel to the chain , the propagating transverse modes are circularly polarized , and the left and right circularly polarized branches have slightly different dispersion relations . as a result ,
if a linearly polarized transverse wave is launched along the chain , it undergoes faraday rotation . for parameters approximating that of a typical metal and for a field of 2 t ,
the faraday rotation is of order 1@xmath3 per ten interparticle spacings , even taking into account single - particle damping . if @xmath2 is perpendicular to the chain , one of the @xmath1 branches mixes with the @xmath0 branch to form two elliptically polarized branches .
our calculations include single - particle damping and can , in principle , be generalized to include radiation damping .
the present work suggests that the dispersion relations of plasmonic waves on chain of nanoparticles can be controlled by immersing the chain in a nematic liquid crystal and varying the director axis , or by applying a magnetic field . .
And you have already written the first three sentences of the full article: the optical properties of small metal particles have been of interest to physicists since the time of maxwell@xcite . such particles , if subjected to light of wavelength much larger than their linear dimensions , exhibit optical resonances due to localized electronic excitations known as `` particle '' or surface " plasmons
. these plasmons can give rise to characteristic absorption peaks , typically in the near - infrared or the visible , which may play an important role in the optical response of dilute suspensions of metal particles in a dielectric host@xcite .
because of recent advances in sample preparation , it has become possible to study _ ordered _ arrays of metal particles in a dielectric host@xcite . in one - dimensional ordered arrays of such closely - spaced particles , waves of plasmonic excitations can propagate along the chains , provided that the interparticle spacing is small compared to the wavelength of light@xcite . in this limit ,.
Please generate the next two sentences of the article | the electric fields produced by the dipole moment of one nanoparticle induces dipole moments on the neighboring nanoparticles .
the dispersion relations for both transverse ( @xmath1 ) and longitudinal ( @xmath0 ) plasmonic waves can then be calculated in the so - called quasistatic approximation@xcite , in which the curl of the electric field is neglected . |
4,046 | Suppose that you have an abstract for a scientific paper: we study the universal relations and normal - phase thermodynamics of a two - component ultracold fermi gas with coexisting @xmath0- and @xmath1-wave interactions . due to the orthogonality of two - body wave functions of different scattering channels ,
the universal thermodynamic relations of the system appear to be direct summations of contributions from each partial - wave scattering channels .
these universal relations are dictated by a set of contacts , which can be associated with either @xmath0- or @xmath1-wave interactions .
interestingly , due to the interplay of @xmath0- and @xmath1-wave interactions on the many - body level , the contacts , and hence all the relevant thermodynamic quantities , behave differently from those with only @xmath0- or @xmath1-wave interactions .
these are manifest in our numerical calculations based on second - order virial expansions for @xmath2k atoms under typical experimental parameters .
a particularly interesting finding is that , due to the coexistence of @xmath0- and @xmath1-wave scatterings , the interaction energy of the repulsive branch features abrupt changes across the @xmath1-wave resonances .
our results can be readily checked experimentally for @xmath2k atoms near the @xmath3 g @xmath1-wave feshbach resonance , where multiple partial - wave scatterings naturally coexist . .
And you have already written the first three sentences of the full article: in ultracold atoms , the typical diluteness condition and short - range interactions can give rise to interesting universal relations among thermodynamic quantities of a many - body system .
these universal relations are independent of the microscopic details of two - body interactions , and have stimulated much research interest . in a unitary fermi gas close to an @xmath0-wave scattering , for instance , the central quantity of these universal relations , tan s contact , has been extensively studied both theoretically and experimentally .
furthermore , the recent radio - frequency ( r.f . ) spectroscopic measurement near a @xmath1-wave feshbach resonance in @xmath2k atoms opens up new possibilities of studying universal relations and thermodynamics in higher partial - wave scattering channels @xcite ..
Please generate the next two sentences of the article | theoretically , it has also been shown recently that a whole family of contacts and universal relations exist in systems with higher partial - wave scattering @xcite .
motivated by this progress , we investigate universal relations and thermodynamics of a two - component degenerate fermi gas with coexisting @xmath0- and @xmath1-wave interactions . |
4,047 | Suppose that you have an abstract for a scientific paper: let @xmath0 be the least number @xmath1 for which there exists a simple graph with @xmath1 vertices having precisely @xmath2 spanning trees .
similarly , define @xmath3 as the least number @xmath1 for which there exists a simple graph with @xmath1 edges having precisely @xmath2 spanning trees . as an @xmath4-cycle has exactly @xmath4 spanning trees
, it follows that @xmath5 . in this paper , we show that @xmath6 and @xmath7 if and only if @xmath8 , which is a subset of euler s idoneal numbers . moreover , if @xmath9 and @xmath10 we show that @xmath11 and @xmath12 this improves some previously estabilished bounds .
* keywords : * number of spanning trees ; extremal graph + * ams subj . class .
( 2010 ) * : 05c35 , 05c05 .
And you have already written the first three sentences of the full article: results related to the problem of counting spanning trees for a graph date back to 1847 . in @xcite
, kirchhoff showed that the number of spanning trees of a graph @xmath13 is closely related to the cofactor of the laplacian matrix of @xmath13 .
later , a number of related results followed . in 1889.
Please generate the next two sentences of the article | , cayley @xcite derived the number of spanning trees for the complete graph on @xmath4 vertices which is @xmath14 . later formulas for various families of graphs have been derived .
for example , it was shown by baron et al . |
4,048 | Suppose that you have an abstract for a scientific paper: the complex zeros of the riemannn zeta - function are identical to the zeros of the riemann xi - function , @xmath0 .
thus , if the riemann hypothesis is true for the zeta - function , it is true for @xmath0 . since @xmath0 is entire , the zeros of @xmath1 , its derivative ,
would then also satisfy a riemann hypothesis .
we investigate the pair correlation function of the zeros of @xmath1 under the assumption that the riemann hypothesis is true .
we then deduce consequences about the size of gaps between these zeros and the proportion of these zeros that are simple . .
And you have already written the first three sentences of the full article: riemann s xi - function is defined by @xmath2 where @xmath3 is the euler @xmath4-function and @xmath5 is the riemann @xmath6-function .
the @xmath7-function is an entire function of order 1 with functional equation @xmath8 and its only zeros are the complex zeros of @xmath9 .
thus , if the riemann hypothesis ( rh ) is true , all the zeros of @xmath0 have real part one half , and the same would hold for all the zeros of the derivative @xmath1 ..
Please generate the next two sentences of the article | we assume rh throughout this paper and investigate the distribution of the zeros @xmath10 of @xmath11 .
the distribution of zeros of @xmath12 is of interest for number - theoretic reasons connected to the problem of landau - siegel zeros , and also in connection to the general behavior of zeros of entire functions under differentiation . |
4,049 | Suppose that you have an abstract for a scientific paper: using the local potential approximation of the exact renormalization group ( rg ) equation , we show the various domains of values of the parameters of the @xmath0-symmetric scalar hamiltonian . in three dimensions , in addition to the usual critical surface @xmath1 ( attraction domain of the wilson - fisher fixed point ) , we explicitly show the existence of a first - order phase transition domain @xmath2 separated from @xmath3 by the tricritical surface @xmath4 ( attraction domain of the gaussian fixed point ) . @xmath2 and @xmath1 are two distinct domains of repulsion for the gaussian fixed point , but @xmath2 is not the basin of attraction of a fixed point .
@xmath2 is characterized by an endless renormalized trajectory lying entirely in the domain of negative values of the @xmath5-coupling .
this renormalized trajectory exists also in four dimensions making the gaussian fixed point ultra - violet stable ( and the @xmath6 renormalized field theory asymptotically free but with a wrong sign of the perfect action ) .
we also show that very retarded classical - to - ising crossover may exist in three dimensions ( in fact below four dimensions ) .
this could be an explanation of the unexpected classical critical behavior observed in some ionic systems . _
pacs 05.10.cc , 05.70.jk , 11.10.hi_ -0.7 cm -2 cm .
And you have already written the first three sentences of the full article: the object of this paper is to carry on studying the local potential approximation of the exact renormalization group ( rg ) equation for the scalar theory @xcite . in a previous publication @xcite ( to be considered as the part i of the present work )
, we had already considered this approximation with a view to qualitatively discuss the connection between the standard perturbative renormalization of field theory ( as it can be found in most textbooks on field theory , see for example @xcite ) and the modern view @xcite in which the renormalized parameters of a field theory are introduced as the `` relevant '' directions of a fixed point ( fp ) of a rg transform .
actually the local potential approximation , which allows us to consider all the powers of the field @xmath7 on the same footing , is an excellent textbook example of the way infinitely many degrees of freedom are accounted for in ( nonperturbative ) rg theory ..
Please generate the next two sentences of the article | almost all the characteristics of the rg theory are involved in this approximation .
the only lacking features are related to phenomena highly correlated to the non local parts neglected in the approximation and when the critical exponent @xmath8 is small ( especially for @xmath9 and @xmath10 ) , one expects the approximation to be qualitatively correct on all aspects of the rg theory @xcite . in the following we look at the domains of attraction or of repulsion of fixed points in the @xmath0 scalar theory in three and four dimensions ( @xmath10 and @xmath9 ) . at first sight |
4,050 | Suppose that you have an abstract for a scientific paper: we prove polynomial upper bounds of geometric ramsey numbers of pathwidth-@xmath0 outerplanar triangulations in both convex and general cases .
we also prove that the geometric ramsey numbers of the ladder graph on @xmath1 vertices are bounded by @xmath2 and @xmath3 , in the convex and general case , respectively .
we then apply similar methods to prove an @xmath4 upper bound on the ramsey number of a path with @xmath5 ordered vertices .
department of applied mathematics , charles university , faculty of mathematics and physics , + malostransk nm . 25 , 118 00 praha 1 , czech republic .
+ ` { cibulka,krcal}@kam.mff.cuni.cz ` + + max - planck - institut fr informatik , + saarbrcken , saarland , germany .
+ ` [email protected] ` + + czech technical university , faculty of information technology , + prague , czech republic .
+ ` [email protected] ` * msc codes : * 52c35 , 05c55 , 05c10 * keywords : * geometric ramsey theory , outerplanar graph , ordered ramsey theory , pathwidth .
And you have already written the first three sentences of the full article: a finite set @xmath6 of points is in a _ general position _ if no three points of @xmath7 are collinear .
the _ complete geometric graph on @xmath7 _ , denoted by @xmath8 , is the complete graph with vertex set @xmath7 , whose edges are drawn as the straight - line segments between pairs of points of @xmath7 .
the set of points @xmath7 is in _ convex position _ if @xmath7 is the set of vertices of a convex polygon ..
Please generate the next two sentences of the article | if @xmath7 is in convex position , we say that @xmath8 is a _ convex complete geometric graph_. krolyi , pach and tth @xcite introduced the concept of ramsey numbers for geometric graphs as follows . given a graph @xmath9 ,
the _ geometric ramsey number _ of @xmath9 , denoted by @xmath10 , is the smallest integer @xmath5 such that every complete geometric graph @xmath11 on @xmath5 vertices with edges arbitrarily coloured by two colours contains a monochromatic non - crossing copy of @xmath9 . |
4,051 | Suppose that you have an abstract for a scientific paper: we discuss recent work showing that in certain cases the membrane paradigm equations governing the dynamics of black hole horizons can be recast as relativistic conservation law equations . in the context of gauge / gravity dualities ,
these equations are interpreted as defining the viscous hydrodynamics of a holographically dual relativistic field theory . using this approach
, one can derive the viscous transport coefficients and the form of the entropy current for field theories dual to gravity plus matter fields . .
And you have already written the first three sentences of the full article: in the past decade there has been much interest in the hydrodynamics of relativistic conformal field theories ( cfts ) , largely due to the ads / cft correspondence between ( quantum ) gravitational theories on asymptotically anti - de - sitter ( ads ) spacetimes in @xmath0 dimensions and cfts in @xmath1 dimensions @xcite . in @xcite it was shown explicitly that the @xmath1-dimensional cft hydrodynamics equations are dual to the gravitational field equations describing the evolution of large scale perturbations of the @xmath0-dimensional black brane .
this has been dubbed the fluid - gravity correspondence .
it has been noticed that this correspondence naturally completes the picture of the old membrane paradigm @xcite of the 1980 s , where black hole horizons are thought of as being analogous to fictitious viscous fluids . in this case , however , the dynamics of the entire spacetime is encoded holographically into the fluid living at the boundary of the spacetime and not at the event horizon @xcite . on the other hand , at least in some circumstances.
Please generate the next two sentences of the article | , the horizon membrane paradigm can be modernized within the context of hydrodynamics as an effective field theory and the fluid - gravity correspondence .
the starting point is an equilibrium solution containing a timelike killing vector field and a stationary causal horizon . |
4,052 | Suppose that you have an abstract for a scientific paper: in this study , we present non - linear spin wave analysis of a quasi 2d spin-@xmath0 @xmath1 antiferromagnet at the parameter regime relevant for the recently studied compound @xmath2 .
we obtain the temperature dependence of the spin wave energy , susceptibility and magnetization using green s function technique and hartree - fock factorization or tyablikov s decoupling approximation .
the comparison of our numerical results with the experimental findings is discussed . magnetic structure factor is calculated and compared with powder neutron diffraction data .
we also study the spin wave behavior of the compound @xmath3 obtained by partial chemical substitution of @xmath4 at @xmath5 sites of the compound @xmath2 ( phys .
rev .
b87 , 054431 ) . due to the superlattice structure of the spin lattice ,
the substituted compound possess multiple spin wave modes .
the spin wave analysis confirms the quasi-1d nature of the substituted system . .
And you have already written the first three sentences of the full article: over the past several years , low dimensional spin systems , belonging to family of cuprates@xcite , vanadates@xcite , titanates@xcite have emerged as a field of active research in the condensed matter community . in this context , the magnetic properties of the layered vanadium compounds @xmath6 ( @xmath7 ) has drawn interest as they are found to be quasi two dimensional ( 2d ) in nature with in - plane spin - frustration that corresponds well to a @xmath1 heisenberg antiferromagnetic ( af ) model@xcite .
early transition metal vanadium ( @xmath83d^34s^2 $ ] ) is in its nominal 4 + valences in the compounds giving rise to the possibility of realizing the spin 1/2 2d af .
the compound @xmath2 , in particular , has attracted attention due to interesting and unusual magnetic properties@xcite , showing weak superexchange ( @xmath9 mev ) mediated low dimensional magnetic behavior of v spins . susceptibility and specific heat measurements@xcite and neutron diffraction results@xcite.
Please generate the next two sentences of the article | have confirmed the quasi 2d spin-@xmath0 af nature for the spin lattice of the system . in spite of existence of a 3d neel temperature of @xmath10
k , the compound shows signatures of short range 2d magnetic correlations well up to 6.95 k@xcite . |
4,053 | Suppose that you have an abstract for a scientific paper: a large fraction of the luminous distant submillimetre - wave galaxies recently detected using the submillimetre common - user bolometer array ( scuba ) camera on the james clerk maxwell telescope appear to be associated with interacting optical counterparts .
we investigate the nature of these systems using a simple hierarchical clustering model of galaxy evolution , in which the large luminosity of the scuba galaxies is assumed to be generated at the epoch of galaxy mergers in a burst of either star formation activity or the fuelling of an active galactic nucleus ( agn ) .
the models are well constrained by the observed spectrum of the far - infrared / submillimetre - wave background radiation and the 60-@xmath0 m counts of low - redshift _ iras _ galaxies .
the ratio between the total amount of energy released during mergers and the mass of dark matter involved must increase sharply with redshift @xmath1 at @xmath2 , and then decrease at greater redshifts .
this result is independent of the fraction of the luminosity of mergers that is produced by starbursts and agn .
one additional parameter the reciprocal of the product of the duration of the enhanced luminosity produced by the merger and the fraction of mergers that induce an enhanced luminosity , which we call the activity parameter is introduced , to allow the relationship between merging dark matter haloes and the observed counts of distant dusty galaxies to be investigated .
the observed counts can only be reproduced if the activity parameter is greater by a factor of about 5 and 100 at redshifts of 1 and 3 respectively , as compared with the present epoch .
hence , if merging galaxies account for the population of scuba galaxies , then the merger process must have been much more violent at high redshifts . we discuss the counts of galaxies and the intensity of background radiation in the optical / near - infrared wavebands in the context of these hierarchical models , and thus investigate the relationship between the populations of....
And you have already written the first three sentences of the full article: the history of star formation in dusty galaxies was recently discussed by blain et al .
( 1999c ) , who assumed that the distant galaxies recently detected using the 450/850-@xmath0 m submillimetre common - user bolometer array ( scuba ) camera ( holland et al .
1999 ) were the high - redshift counterparts of local ultraluminous _ iras _ galaxies ..
Please generate the next two sentences of the article | the global star formation rate ( sfr ) in dust obscured galaxies was inferred to be significantly greater than that of optically selected high - redshift galaxies ( steidel et al .
1996a , b , 1999 ) , subject to the uncertain fraction of the luminosity of the submillimetre - selected samples of galaxies ( smail , ivison & blain 1997 ; barger et al . |
4,054 | Suppose that you have an abstract for a scientific paper: using functional derivatives with respect to the free correlation function we derive a closed set of schwinger - dyson equations in @xmath0-theory . its conversion to graphical recursion relations
allows us to systematically generate all connected and one - particle irreducible feynman diagrams for the two- and four - point function together with their weights . .
And you have already written the first three sentences of the full article: quantum and statistical field theory investigate the influence of field fluctuations on the @xmath1-point functions .
interactions lead to an infinite hierarchy of schwinger - dyson equations for the @xmath1-point functions .
these integral equations can only be closed approximately , for instance , by the well - established the self - consistent method of kadanoff and baym ..
Please generate the next two sentences of the article | + recently , it has been shown that the schwinger - dyson equations of qed can be closed in a certain functional - analytic sense . using functional derivatives with respect to the free propagators and
the interaction two closed sets of equations were derived . |
4,055 | Suppose that you have an abstract for a scientific paper: density inhomogeneities along the line - of - sight distort fluctuations in the cosmic microwave background .
usually , this effect is thought of as a small second - order effect that mildly alters the statistics of the microwave background fluctuations .
we show that there is a first - order effect that is potentially observable if we combine microwave background maps with large redshift surveys .
we introduce a new quantity that measures this lensing effect , @xmath0 where @xmath1 is the microwave background temperature and @xmath2 is the lensing due to matter in the region probed by the redshift survey .
we show that the expected signal is first order in the gravitational lensing bending angle , @xmath3 and find that it should be easily detectable , ( s / n)@xmath4 if we combine the microwave anisotropy probe satellite and sloan digital sky survey data . measurements of this cross - correlation will directly probe the `` bias '' factor , the relationship between fluctuations in mass and fluctuations in galaxy counts . .
And you have already written the first three sentences of the full article: the next several years should be very exciting for cosmologists : microwave anisotropy probe ( map ; @xcite ) and planck ( @xcite ) will make high resolution maps of the microwave background sky ; while the sloan digital sky survey ( sdss ; @xcite ; see also http://www-sdss.fnal.gov:8000/ ) will measure redshifts of 10@xmath5 galaxies and positions of 10@xmath6 galaxies . in this paper , we explore the _ direct _ connection between these two measurements through gravitational lensing : the path of a cosmic microwave background ( cmb ) photon is distorted by inhomogeneities in the matter distribution ; galaxy surveys detect these inhomogeneities as fluctuations in galaxy number counts .
the effect of the gravitational lensing on the cmb anisotropies has been studied by many authors .
the uncomfortably low upper limits ( @xcite ) provoked a great deal of controversy ( @xcite ) about the possibility that gravitational lensing washes out the intrinsic fluctuation ..
Please generate the next two sentences of the article | after the detection by the cosmic background explorer ( cobe ; @xcite ) , there has been renewal of interest ( @xcite , b , @xcite , b , @xcite ) in investigating how the cmb power spectrum is redistributed owing to gravitational lensing .
for example , seljak ( 1996 ) recently presented detailed calculations of gravitationally deflected cmb power spectra , including the effect of the nonlinear evolution of matter density fluctuations . |
4,056 | Suppose that you have an abstract for a scientific paper: neutral atomic hydrogen ( ) gas in interstellar space is largely organized into filaments , loops , and shells , the most prominent of which are `` supershells '' .
these gigantic structures requiring @xmath0 erg to form are generally thought to be produced by either the explosion of multiple supernovae ( sne ) in ob associations or alternatively by the impact of high - velocity clouds ( hvcs ) falling to the galactic disk .
here we report the detection of a kiloparsec ( kpc)-size supershell in the outskirts of the milky way with the compact hvc 040 + 01@xmath1282 ( hereafter chvc040 ) at its geometrical center using the `` inner - galaxy arecibo l - band feed array '' 21-cm survey data .
the morphological and physical properties of both objects suggest that chvc040 , which is either a fragment of a nearby disrupted galaxy or a cloud originated from an intergalactic accreting flow , collided with the disk @xmath2 myrs ago to form the supershell .
our result shows that some compact hvcs can survive their trip through the galactic halo and inject energy and momentum into the milky way disk . .
And you have already written the first three sentences of the full article: supershells are large gaseous shells of radius greater than a few hundred parsecs .
they are distinct from other shell - like structures in their extraordinarily large energy requirement , i.e. , @xmath3 erg , which corresponds to @xmath4 supernova ( sn ) explosions @xcite .
about twenty supershells have been found in the milky way , and numerous neutral atomic hydrogen ( ) holes corresponding to supershells have been discovered in nearby dwarfs and spiral galaxies @xcite ..
Please generate the next two sentences of the article | these gigantic structures are generally thought to arise from multiple sn explosions in stellar ob associations .
but most supershells are missing a stellar association in their interior , and the number of supershells and their energies are usually incompatible with the level of star formation in those galaxies @xcite . |
4,057 | Suppose that you have an abstract for a scientific paper: we give a short determination of the distribution of the number of @xmath0-rational points on a random trigonal curve over @xmath0 , in the limit as the genus of the curve goes to infinity .
in particular , the expected number of points is @xmath1 , contrasting with recent analogous results for cyclic @xmath2-fold covers of @xmath3 and plane curves which have an expected number of points of @xmath4 ( by work of kurlberg , rudnick , bucur , david , feigon and laln ) and curves which are complete intersections which have an expected number of points @xmath5 ( by work of bucur and kedlaya ) .
we also give a conjecture for the expected number of points on a random @xmath6-gonal curve with full @xmath7 monodromy based on function field analogs of bhargava s heuristics for counting number fields . .
And you have already written the first three sentences of the full article: if we fix a finite field @xmath0 , we can ask about the distribution of the number of ( @xmath0-rational ) points on a random curve over @xmath0 . there has been a surge of recent activity on this question including definitive answers of kurlberg and rudnick for hyperelliptic curves @xcite , of bucur , david , feigon and laln for cyclic @xmath2-fold covers of @xmath3 @xcite , of bucur , david , feigon and laln for plane curves @xcite , and of bucur and kedlaya on curves that are complete intersections in smooth quasiprojective subschemes of @xmath8 @xcite . in the first three cases ,
the average number of points on a curve in the family is @xmath4 .
in contrast , for curves that are complete intersections in @xmath8 , the average number of points is @xmath5 , despite , as pointed out by bucur and kedlaya , the abundance of @xmath0 points lying around in @xmath8 . in this paper , we give the distribution of the number of points on trigonal curves over @xmath0 ( i.e. curves with a degree @xmath9 map to @xmath3 ) , and in particular show that the average number of points is greater that @xmath4 ..
Please generate the next two sentences of the article | let @xmath10 our main theorem is the following .
[ t : main ] let @xmath0 have characteristic @xmath11 . |
4,058 | Suppose that you have an abstract for a scientific paper: the rapid falloff of the oscillator functions at large radius ( gaussian asymptotics ) makes them poorly suited for the description of the asymptotic properties of the nuclear wave function , a problem which becomes particularly acute for halo nuclei .
we consider an alternative basis for _ ab initio _ no - core configuration interaction ( ncci ) calculations , built from coulomb - sturmian radial functions , allowing for realistic ( exponential ) radial falloff .
ncci calculations are carried out for the neutron - rich isotopes , and estimates are made for the rms radii of the proton and neutron distributions .
+ * keywords : * _ no - core configuration interaction ; coulomb - sturmian basis ; neutron halo ; nuclear radii _ * * halo nuclei with the coulomb - sturmian basis + @xmath0__department of physics , university of notre dame , notre dame , indiana 46556 , usa _ _
+ @xmath1__department of physics and astronomy , iowa state university , ames , iowa 50011 , usa _ _ .
And you have already written the first three sentences of the full article: the _ ab initio _ theoretical description of light nuclei is based on direct solution of the nuclear many - body problem given realistic nucleon - nucleon interactions . in no - core
configuration interaction ( ncci ) calculations @xcite , the nuclear many - body problem is formulated as a matrix eigenproblem .
the hamiltonian is represented in terms of basis states which are antisymmetrized products of single - particle states for the full @xmath2-body system of nucleons , _.
Please generate the next two sentences of the article | i.e. _ , with no assumption of an inert core .
in practice , the nuclear many - body calculation must be carried out in a truncated space . |
4,059 | Suppose that you have an abstract for a scientific paper: `` dark photons '' , light new vector particles @xmath0 kinetically mixed with the photon , are a frequently considered extension of the standard model . for masses below 10 kev
they are emitted from the solar interior . in the limit of small mass @xmath1
the dark photon flux is strongly peaked at low energies and we demonstrate that the constraint on the atomic ionization rate imposed by the results of the xenon10 dark matter experiment sets the to - date most stringent limit on the kinetic mixing parameter of this model : @xmath2 .
the result significantly improves previous experimental bounds and surpasses even the most stringent astrophysical and cosmological limits in a seven - decade - wide interval of @xmath1 . .
And you have already written the first three sentences of the full article: in the recent years , the model of light vector particles with kinetic mixing to the standard model photon has received tremendous attention , theoretically as well as experimentally . whereas @xmath3 is mainly being probed in medium - to - high energy collider experiments , masses in the sub - mev regime are subject to severe astrophysical and cosmological constraints .
below @xmath4 ev , those limits are complemented by direct laboratory searches for dark photons in non - accelerator type experiments . among the most prominent
are the `` light - shining - through - wall '' experiments ( lsw ) @xcite and the conversion experiments from the solar dark photon flux , `` helioscopes '' @xcite ; a collection of low - energy constraints on dark photons can _ e.g. _ be found in the recent review @xcite ..
Please generate the next two sentences of the article | helioscopes derive their sensitivity from the fact that such light vectors are easily produced in astrophysical environments , such as in the solar interior , covering a wide range of masses up to @xmath5 few kev . in general , stellar astrophysics provides stringent constraints on any type of light , weakly - interacting particles once the state becomes kinematically accessible @xcite . only in a handful of examples
does the sensitivity of terrestrial experiments match the stellar energy loss constraints . here |
4,060 | Suppose that you have an abstract for a scientific paper: inspired by the problem of sensory coding in neuroscience , we study the maximum entropy distribution on weighted graphs with a given expected degree sequence . this distribution on graphs is characterized by independent edge weights parameterized by vertex potentials at each node . using the general theory of exponential family distributions , we prove the existence and uniqueness of the maximum likelihood estimator ( mle ) of the vertex parameters .
we also prove the consistency of the mle from a single graph sample , extending the results of chatterjee , diaconis , and sly for unweighted ( binary ) graphs .
interestingly , our extensions require an intricate study of the inverses of diagonally dominant positive matrices . along the way
, we derive analogues of the erds - gallai criterion of graphical sequences for weighted graphs . .
And you have already written the first three sentences of the full article: maximum entropy models are an important class of statistical models for biology .
for instance , they have been found to be a good model for protein folding @xcite , antibody diversity @xcite , neural population activity @xcite , and flock behavior @xcite . in this paper
we develop a general framework for studying maximum entropy distributions on weighted graphs , extending recent work of chatterjee , diaconis , and sly @xcite ..
Please generate the next two sentences of the article | the development of this theory is partly motivated by the problem of sensory coding in neuroscience . in the brain , information is represented by discrete electrical pulses , called _ action potentials _ or _ spikes _ @xcite .
this includes neural representations of sensory stimuli which can take on a continuum of values . |
4,061 | Suppose that you have an abstract for a scientific paper: this paper is concerned with extensions of the classical marenko pastur law to time series .
specifically , @xmath0-dimensional linear processes are considered which are built from innovation vectors with independent , identically distributed ( real- or complex - valued ) entries possessing zero mean , unit variance and finite fourth moments .
the coefficient matrices of the linear process are assumed to be simultaneously diagonalizable . in this
setting , the limiting behavior of the empirical spectral distribution of both sample covariance and symmetrized sample autocovariance matrices is determined in the high - dimensional setting @xmath1 for which dimension @xmath0 and sample size @xmath2 diverge to infinity at the same rate .
the results extend existing contributions available in the literature for the covariance case and are one of the first of their kind for the autocovariance case . , .
And you have already written the first three sentences of the full article: one of the exciting developments in statistics during the last decade has been the development of the theory and methodologies for dealing with high - dimensional data . the term _ high dimension _ is primarily interpreted as meaning that the dimensionality of the observed multivariate data is comparable to the available number of replicates or subjects on which the measurements on the different variables are taken .
this is often expressed in the asymptotic framework as @xmath3 , where @xmath0 denotes the dimension of the observation vectors ( forming a triangular array ) and @xmath2 the sample size .
much of this development centered on understanding the behavior of the sample covariance matrix and especially its eigenvalues and eigenvectors , due to their role in dimension reduction , in estimation of population covariances and as building block of numerous inferential procedures for multivariate data ..
Please generate the next two sentences of the article | comprehensive reviews of this topic can be found in johnstone @xcite and paul and aue @xcite .
one most notable high - dimensional phenomena associated with sample covariance matrices is that the sample eigenvalues do not converge to their population counterparts if dimension and sample sizes remain comparable even as the sample size increases . a formal way to express |
4,062 | Suppose that you have an abstract for a scientific paper: we investigate the phenomenology of composite 2-higgs doublet models ( c2hdms ) of various yukawa types based on the global symmetry breaking @xmath0 .
the kinetic term and the yukawa lagrangian are constructed in terms of the pseudo nambu - goldstone boson ( pngb ) matrix and a * 6 * -plet of fermions under @xmath1 .
the scalar potential is assumed to be the same as that of the elementary 2-higgs doublet model ( e2hdm ) with a softly - broken discrete @xmath2 symmetry .
we then discuss the phenomenological differences between the e2hdm and c2hdm by focusing on the deviations from standard model ( sm ) couplings of the discovered higgs state ( @xmath3 ) as well as on the production cross sections and branching ratios ( brs ) at the large hadron collider ( lhc ) of extra higgs bosons .
we find that , even if the same deviation in the @xmath4 ( @xmath5 ) coupling is assumed in both scenarios , there appear significant differences between e2hdm and c2hdm from the structure of the yukawa couplings , so that production and decay features of extra higgs bosons can be used to distinguish between the two scenarios . .
And you have already written the first three sentences of the full article: after the discovery of a higgs boson in july 2012 @xcite , an intense period of analysis of its properties has begun and is bearing fruits .
we now know that this object is very consistent with the spinless scalar state embedded in the sm .
following the precision measurement of its mass , around 125 gev , its couplings to all other states of the sm can be derived and compared with experimental data ..
Please generate the next two sentences of the article | agreement between sm and experimental results is presently within a few tens of percent at worse , thus leaving some scope for a beyond the sm ( bsm ) higgs sector . by bearing in mind that the discovered higgs state has a doublet nature , amongst the many new physics scenarios available embedding such structures , those easier to deal with are clearly 2-higgs doublet models ( 2hdms ) .
in fact , these scenarios always include a neutral scalar higgs state that can play the role of the discovered one , which as intimated is very sm - like . furthermore , they are also easily compliant with past collider data ( from lep / slc and tevatron ) as well as present ones ( from the lhc ) while still offering a wealth of new higgs states and corresponding signals that can be searched for by the atlas and cms collaborations . |
4,063 | Suppose that you have an abstract for a scientific paper: intermodal interactions displayed through the phenomena of mode coupling and conversion in optical systems are treated by means of the lindstedt - poincar perturbation method of strained parameters more widely known in classical quantum mechanics and quantum chemistry as the stationary perturbation technique .
the focus here is on the mode conversion at the points of virtual phase matching ( otherwise called anticrossings or avoided crossings ) associated with the maximum conversion efficiency .
the method is shown to provide a convenient tool to deal with intermodal interactions at anticrossings interactions induced by any kind of perturbation in dielectric index profile of the waveguide , embracing optical inhomogeneity , magnetization of arbitrary orientation , and nonlinearity .
closed - form analytic expressions are derived for the minimum value of mode mismatch and for the length of complete mode conversion ( the coupling length , or the beat length ) in generic waveguiding systems exhibiting anticrossings .
demonstrating the effectiveness of the method , these general expressions are further applied to the case of @xmath0 mode conversion in ( i ) a multilayer gyrotropic waveguide under piecewise - constant , arbitrarily oriented magnetization , and ( ii ) an optically - inhomogeneous planar dielectric waveguide an example which the standard coupled - mode theory fails to describe . .
And you have already written the first three sentences of the full article: mode coupling and conversion are commonly known and primarily important phenomena in fiber and integrated optics , either hindering or fueling the operation of numerous devices and elements , e.g. , electro - optical and acousto - optical switches and modulators , waveguide couples , power splitters , wavelength filters , and others @xcite . when a mode of certain configuration transverses the structure and converts into some other mode , say , due to the externally induced perturbation in optical properties or geometrical configuration of the structure or due to the imperfectness of the materials used , or when the exchange of energy between the guided modes of adjacent waveguides occurs anyway we face the phenomena of mode coupling and conversion .
the crucial regime for the mode coupling is in the vicinity of the points of virtual phase matching ( otherwise referred to as `` anticrossings '' or `` avoided crossings '' a terminology brought about from quantum mechanics and solid - state physics ) . at anticrossings ,
the complete mode conversion can be achieved , which makes tailoring this regime particularly important for the applications . for a positive example , let me mention a promising method for controllable dispersion compensation in photonic bandgap fibers based on weak interactions at anticrossings between the core - guided mode and a mode localized in an intentionally introduced defect of the crystal @xcite ..
Please generate the next two sentences of the article | an opposing example of technology strains due to the undesirable intermodal interactions is radiation losses caused by the coupling of the guided mode to radiation modes in a two - dimensional photonic crystal etched into a planar waveguide @xcite .
a dominating theoretical tool for the whole of mode coupling and conversion phenomena ( except a few cases when rigorous analytical treatment is possible @xcite ) is the coupled - mode , or the coupled - wave , formalism @xcite that was first proposed more than fifty years ago and since then became commonplace in both optical engineering research and textbook literature . |
4,064 | Suppose that you have an abstract for a scientific paper: the supercell method is used to study the variation of the photonic bandgaps in one - dimensional photonic crystals under random perturbations to thicknesses of the layers .
the results of both plane wave and analytical band structure and density of states calculations are presented along with the transmission coefficient as the level of randomness and the supercell size is increased .
it is found that higher bandgaps disappear first as the randomness is gradually increased .
the lowest bandgap is found to persist up to a randomness level of @xmath0 percent . .
And you have already written the first three sentences of the full article: since the pioneering work of e. yablonovitch @xcite and s. john @xcite , research on photonic crystals(pcs ) has enjoyed a nearly exponential increase . the manufacture of pcs at the optical regime has become a reality @xcite .
manufacturing brings with it the practical reality of random errors introduced during the manufacturing process and it is the effect of these random errors on the desirable features of pcs , namely photonic band gaps , that we wish to address in this paper .
bandgaps in pcs depend on two crucial properties : an infinite _ and _ perfect translational symmetry ..
Please generate the next two sentences of the article | clearly , in real life no crystal is infinite in size or perfectly periodic .
when randomness is introduced in the geometry of the pc , one quantity of interest is the size of the bandgaps as the level of randomness is increased , and whether the bandgaps of the bulk perfect pc will survive the randomness . |
4,065 | Suppose that you have an abstract for a scientific paper: convection and turbulence in stellar atmospheres have a significant effect on the emergent flux from late - type stars .
the theoretical advancements in convection modelling over recent years have proved challenging for the observers to obtain measurements with sufficient precision and accuracy to allow discrimination between the various predictions .
an overview of the current observational techniques used to evaluate various convection theories is presented , including photometry , spectrophotometry , and spectroscopy .
the results from these techniques are discussed , along with their successes and limitations .
the prospects for improved observations of stellar fluxes are also given . .
And you have already written the first three sentences of the full article: the gross properties of a star , such as broad - band colours and flux distributions , are significantly affected by the effects of convection in stars later than mid a - type .
consequently , our modelling of convection in stellar atmosphere models can significantly alter our interpretation of observed phenomena . by comparison with stars of known @xmath0 and/or @xmath1 ( the fundamental stars ) , we can evaluate different treatments of convection in model atmosphere calculations .
photometric indices are a fast and efficient method for determining approximate atmospheric parameters of stars . for the commonly - used strmgren @xmath2 system a vast body of observational data exists which can be used to estimate parameters using calibrated model grids ( e.g. ( * ? ? ?.
Please generate the next two sentences of the article | * moon & dworetsky 1985 ) , ( * ? ? ?
* smalley & dworetsky 1995 ) ) . |
4,066 | Suppose that you have an abstract for a scientific paper: we study the transport through side - coupled double quantum dots , connected to normal and superconducting ( sc ) leads with a t - shape configuration .
we find , using the numerical renormalization group , that the coulomb interaction suppresses sc interference in the side dot , and enhances the conductance substantially in the kondo regime .
this behavior stands in total contrast to a wide kondo valley seen in the normal transport . the sc proximity penetrating into the interfacial dot pushes the kondo clouds , which screens the local moment in the side dot , towards the normal lead to make the singlet bond long .
the conductance shows a peak of unitary limit as the cloud expands .
furthermore , two separate fano structures appear in the gate - voltage dependence of the andreev transport , where a single reduced plateau appears in the normal transport . .
And you have already written the first three sentences of the full article: observation of the kondo effect in a quantum dot ( qd ) @xcite has stimulated researches in the field of quantum transport , and recent experimental developments enable one to examine the kondo physics in a variety of systems , such as an aharonov - bohm ( ab ) ring with a qd and double quantum dots ( dqd ) . in these systems
multiple paths for electron propagation also affect the tunneling currents , and the interference causes fano - type asymmetric line shapes .
superconductivity also brings rich and interesting features into the quantum transport ..
Please generate the next two sentences of the article | competition between superconductivity and the kondo effect has been reported to be observed in carbon nanotube qd and in semiconductor nanowires .
@xcite furthermore , interplay between the andreev scattering and the kondo effect has been studied intensively for a qd coupled to a normal ( n ) lead and superconductor ( s ) , theoretically @xcite and experimentally . |
4,067 | Suppose that you have an abstract for a scientific paper: the quasinormal modes ( qnms ) associated with the decay of dirac field perturbation around a schwarzschild black hole is investigated by using continued fraction and hill - determinant approaches .
it is shown that the fundamental quasinormal frequencies become evenly spaced for large angular quantum number and the spacing is given by @xmath0 .
the angular quantum number has the surprising effect of increasing real part of the quasinormal frequencies , but it almost does not affect imaginary part , especially for low overtones .
in addition , the quasinormal frequencies also become evenly spaced for large overtone number and the spacing for imaginary part is @xmath1 which is same as that of the scalar , electromagnetic , and gravitational perturbations .
= 0.65 cm .
And you have already written the first three sentences of the full article: motivated by the beliefs that one can directly identify a black hole existence by comparing qnms with the gravitational waves observed in the universe , and the study of qnms may lead to a deeper understanding of the thermodynamic properties of black holes in loop quantum gravity @xcite @xcite , as well as the qnms of anti - de sitter black holes have a direction interpretation in terms of the dual conformal field theory @xcite @xcite @xcite , the investigation of qnms in black hole spacetimes becomes appealing recent years .
since regge and wheeler @xcite first presented the idea of the qnms and chandrasekhar and detweller @xcite worked out the numerically calculation of the qnms for the schwarzschild black hole , a great deal of effort has been contributed to compute the qnms of the black holes @xcite-@xcite for fields of integer spin , such as the scalar , electromagnetic and gravitational perturbations . on the contrary , the study of the qnms of the dirac field is very limited @xcite@xcite@xcite .
cho @xcite studied the qnms of the dirac field of the schwarzschild black hole with the help of the third - order wkb method , and zhidenko @xcite extended the study to the case of the schwarzschild - de sitter black hole by using the sixth - order wkb method ..
Please generate the next two sentences of the article | we @xcite investigated the dirac qnms of the reissner - nordstrm de sitter black hole using the pshl - teller potential approximation .
nevertheless , in these papers the study of the dirac qnms were limited by using wkb or pshl - teller potential approximative methods . |
4,068 | Suppose that you have an abstract for a scientific paper: many extrasolar ( bound ) terrestrial planets and free - floating ( unbound ) planets have been discovered .
the existence of bound and unbound terrestrial planets with liquid water is an important question , and of particular importance is the question of their habitability . even for a globally ice - covered planet , geothermal heat from the planetary interior may melt the interior ice , creating an internal ocean covered by an ice shell . in this paper
, we discuss the conditions that terrestrial planets must satisfy for such an internal ocean to exist on the timescale of planetary evolution .
the question is addressed in terms of planetary mass , distance from a central star , water abundance , and abundance of radiogenic heat sources .
in addition , we investigate the structures of the surface - h@xmath0o layers of ice - covered planets by considering the effects of ice under high pressure ( high - pressure ice ) . as a fiducial case , @xmath1 planet at 1 au from its central star and with 0.6 to 25 times
the h@xmath0o mass of earth could have an internal ocean .
we find that high - pressure ice layers may appear between the internal ocean and the rock portion on a planet with an h@xmath0o mass over 25 times that of earth .
the planetary mass and abundance of surface water strongly restrict the conditions under which an extrasolar terrestrial planet may have an internal ocean with no high - pressure ice under the ocean .
such high - pressure - ice layers underlying the internal ocean are likely to affect the habitability of the planet . .
And you have already written the first three sentences of the full article: since the first extrasolar planet was discovered in 1995 @xcite , more than 800 exoplanets have been detected as of march 2013 , owing to improvements in both observational instruments and the methods of analysis .
although most known exoplanets are gas giants , estimates based on both theory and observation indicates that terrestrial planets are also common @xcite .
supporting these estimates is the fact that earth - like planets have indeed been discovered ..
Please generate the next two sentences of the article | moreover , space telescopes ( e.g. , _ kepler _ ) have now released observational data about many terrestrial - planet candidates . whether terrestrial planets with liquid water exist is an important question to consider because it lays the groundwork for the consideration of habitability .
the orbital range around a star for which liquid water can exist on a planetary surface is called the habitable zone ( hz ) ( hart 1979 ; kasting et al . |
4,069 | Suppose that you have an abstract for a scientific paper: w50 remains the only supernova remnant ( snr ) confirmed to harbor a microquasar : the powerful enigmatic source ss 433 .
our past study of this fascinating snr revealed two x - ray lobes distorting the radio shell as well as non - thermal x - rays at the site of interaction between the ss 433 eastern jet and the eastern lobe of w50 . in this paper
we present the results of a 75 ksec acis - i observation of the peak of w50-west targeted to 1 ) determine the nature of the x - ray emission and 2 ) correlate the x - ray emission with that in the radio and infrared domains .
we have confirmed that at the site of interaction between the western jet of ss 433 and dense interstellar gas the x - ray emission is non - thermal in nature . the helical pattern observed in radio is also seen with .
no correlation was found between the infrared and x - ray emission . , ,
, binaries : close , ism : individual ( w50 ) , x - rays : stars , stars : individual ( ss 433 ) , radiation mechanisms : non - thermal , supernova remnants .
And you have already written the first three sentences of the full article: ss 433 is a peculiar binary system , consisting of a black hole ( as proposed by lopez et al . , 2005 ) and a massive companion .
this system is accreting at a super - eddington rate , and is expelling two - sided relativistic jets at a velocity of 0.26c .
these jets precess in a cone of half - opening angle of 20@xmath0 @xcite ..
Please generate the next two sentences of the article | ss 433 is near the center of w50 , a large 2@xmath11@xmath0 nebula stretched in the east - west direction , and catalogued as an snr @xcite.the ss 433/w50 system is the only galactic object known of its kind , giving rise to a unique laboratory to study the association between snrs and black holes as well as the interaction between relativistic jets and the surrounding medium .
this system has been studied extensively in radio continuum and hi @xcite , millimetre wavelengths @xcite , and in x - rays with and ( * ? ? ? * and references therein ) and with _ rxte _ ( safi - harb & kotani , 2002 , safi - harb & petre , 1999 ) . from this multi - wavelength study , it was concluded that the morphology and energetics of w50 are consistent with the picture of the jets interacting with an inhomogeneous medium and likely hitting a denser cloud in the west . |
4,070 | Suppose that you have an abstract for a scientific paper: in three spatial dimensions , in the unitary limit of a non - relativistic quantum bose or fermi gas , the scattering length diverges .
this occurs at a renormalization group fixed point , thus these systems present interesting examples of interacting scale - invariant models with dynamical exponent @xmath0 .
we study this problem in two and three spatial dimensions using the s - matrix based approach to the thermodynamics we recently developed .
it is well suited to the unitary limit where the s - matrix @xmath1 , since it allows an expansion in the inverse coupling .
we define a meaningful scale - invariant , unitary limit in two spatial dimensions , where again the scattering length diverges . in the two - dimensional case ,
the integral equation for the pseudo - energy becomes transcendentally algebraic , and we can easily compute the various universal scaling functions as a function of @xmath2 , such as the energy per particle .
the ratio of the shear viscosity to the entropy density @xmath3 is above the conjectured lower bound of @xmath4 for all cases except attractive bosons . for attractive 2-component fermions , @xmath5 , whereas for attractive bosons @xmath6 .
\def\ ] ] ] @xmath7 ) # 1#2#1 # 2 # 11 # 1 # 1#1 # 1#2#1 # 2 # 1#1 # 1 | # 1 pi # 1e^^#1 # 1_#1 # 1#2 # 1 , # 2 pi # 1e^^#1
# 1_#1 = cmss12 = cmu10 scaled1 # 1 pid(2)^d # 1|#1 # 1#1 | # 1#1 0=0=0 0 by-1exa # 1dim[#1 ] .
And you have already written the first three sentences of the full article: in three spatial dimensions , in the unitary limit of a quantum bose or fermi gas with point - like interactions , the scattering length diverges .
`` unitary '' here refers to the limit on the cross section imposed by unitarity .
these systems provide intriguing examples of interacting , scaling invariant theories with dynamical exponent @xmath0 , i.e. non - relativistic ..
Please generate the next two sentences of the article | the infinite scattering length occurs at a fixed point of the renormalization group in the zero temperature theory , thus the models are quantum critical .
the only energy scales in the problem are the temperature and chemical potential , and thermodynamic properties are expected to reveal universal behavior . |
4,071 | Suppose that you have an abstract for a scientific paper: we develop a theory of tunneling spectroscopy of interacting electrons in a non - equilibrium quantum wire coupled to reservoirs .
the problem is modelled as an out - of - equilibrium luttinger liquid with spatially dependent interaction .
the interaction leads to the renormalization of the tunneling density of states , as well as to the redistribution of electrons over energies .
energy relaxation is controlled by plasmon scattering at the boundaries between regions with different interaction strength , and affects the distribution function of electrons in the wire as well as that of electrons emitted from the interacting regions into non - interacting electrodes .
# 1eq .
( [ # 1 ] ) # 1([#1 ] ) .
And you have already written the first three sentences of the full article: one - dimensional ( 1d ) interacting fermionic systems show remarkable physical properties and are promising elements for future nanoelectronics .
the electron - electron interaction manifests itself in a particularly dramatic way in 1d systems , inducing a strongly correlated electronic state
luttinger liquid ( ll ) @xcite . a paradigmatic experimental realization of quantum wires are carbon nanotubes @xcite ; for a recent review see ref . ..
Please generate the next two sentences of the article | further realizations encompass semiconductor , metallic and polymer nanowires , as well as quantum hall edges .
there is currently a growing interest in non - equilibrium phenomena on nanoscales . |
4,072 | Suppose that you have an abstract for a scientific paper: we have investigated the eclipse of the 23 ms pulsar , psr j0737@xmath03039a , by its 2.8 s companion psr j0737@xmath03039b in the recently discovered double pulsar system using data taken with the green bank telescope at 820 mhz .
we find that the pulsed flux density at eclipse is strongly modulated with the periodicity of the 2.8 s pulsar .
the eclipse occurs earlier and is deeper at those rotational phases of b when its magnetic axis is aligned with the line of sight than at phases when its magnetic axis is at right angles to the line of sight .
this is consistent with the eclipse of a being due to synchrotron absorption by the shock - heated plasma surrounding b , the asymmetry arising from the higher plasma densities expected in the b magnetosphere s polar cusps . .
And you have already written the first three sentences of the full article: the two pulsars in the recently discovered double pulsar binary system , and ( hereafter simply `` a '' and `` b '' ) have periods of @xmath1 ms and @xmath2 s. they are in a 2.4-hr mildly - eccentric orbit that we view nearly edge - on , with an inclination angle of @xmath3 ( burgay et al . 2003 ,
lyne et al . 2004 ) .
the phenomenology exhibited by this system is extremely rich ..
Please generate the next two sentences of the article | the flux density of the b pulsar varies dramatically and systematically around the orbit ( lyne et al .
2004 , ramachandran et al . |
4,073 | Suppose that you have an abstract for a scientific paper: hadron yields in high energy heavy ion collisions have been fitted with thermal models using standard ( extensive ) statistical distributions .
these models give insight into the freeze - out conditions at varying beam energies and lead to a systematic consistent picture of freeze - out conditions at all beam energies . in this paper
we investigate changes to this analysis when the statistical distributions are replaced by non - extensive tsallis distributions for hadrons .
we investigate the particle yields at sps and rhic energies and obtain better fits with smaller @xmath0 for the same hadron data , as applied earlier in the thermal fits for sps energies but not for rhic energies . .
And you have already written the first three sentences of the full article: after many years of investigating hadron - hadron and heavy ion collisions , the study of hadron production remains an active and important field of research .
the lack of detailed knowledge of the microscopic mechanisms has led to the use of many different models , often from completely opposite directions .
thermal models , based on statistical weights for produced hadrons @xcite , are very successful in describing particle yields at different beam energies @xcite , especially in heavy ion collisions ..
Please generate the next two sentences of the article | these models assume the formation of a system which is in thermal and chemical equilibrium in the hadronic phase and is characterised by a set of thermodynamic variables for the hadronic phase .
the deconfined period of the time evolution dominated by quarks and gluons remains hidden : full equilibration generally washes out and destroys large amounts of information about the early deconfined phase . |
4,074 | Suppose that you have an abstract for a scientific paper: we combine experiment and theory to investigate the diffusive and subdiffusive dynamics of paramagnetic colloids driven above a two - state flashing potential .
the magnetic potential was realized by periodically modulating the stray field of a magnetic bubble lattice in a uniaxial ferrite garnet film . at large amplitudes @xmath0 of the driving field ,
the dynamics of particles resembles an ordinary random walk with a frequency - dependent diffusion coefficient .
however , subdiffusive and oscillatory dynamics at short time scales is observed when decreasing @xmath0 .
we present a persistent random walk model to elucidate the underlying mechanism of motion , and perform numerical simulations to demonstrate that the anomalous motion originates from the dynamic disorder in the structure of the magnetic lattice , induced by slightly irregular shape of bubbles . .
And you have already written the first three sentences of the full article: transport and diffusion of microscopic particles through periodic potentials is a rich field of research from both fundamental and technological points of view @xcite .
investigation of the particle motion along ordered @xcite or disordered @xcite energy landscapes helps to better understand the dynamics in more complex situations , such as abrikosov @xcite and josephson vortices in superconductors @xcite , cell migration @xcite , or transport of molecular motors @xcite .
moreover , a periodic potential can be used to perform precise particle sorting and fractionation @xcite , thus , being of significant impact in diverse fields in analytical science and engineering which make use of microfluidic devices ..
Please generate the next two sentences of the article | colloidal systems provide an ideal opportunity to investigate different transport scenarios , because of having particle sizes in the visible wavelength range and dynamical time scales which are experimentally accessible . in order to force colloidal particles to move along periodic or random trajectories ,
static potentials can be readily realized by using optical @xcite , magnetic @xcite , or electric fields @xcite . |
4,075 | Suppose that you have an abstract for a scientific paper: the paradigm that young neutron stars ( nss ) evolve as rapidly rotating crab - like pulsars requires re - examination .
evidence is accumulating that , in fact , many young ns are slowly rotating ( @xmath0-s ) x - ray pulsars , lacking in detectable radio emission .
we present new results on three radio - quiet ns candidates associated with supernova remnants , which suggests that alternative evolutionary - paths exist for young pulsars .
these include the 12-s pulsator in kes 73 , the 7-s pulsar near kes 75 , and the enigmatic x - ray source in rcw 103 .
we postulate that such objects account for the apparent paucity of radio pulsars in supernova remnants .
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And you have already written the first three sentences of the full article: neutron stars are thought to be born as rapidly rotating ( @xmath1 ms ) radio pulsars created during a type ii / ib supernova explosion involving a massive star .
their existence was postulated in 1934 by baade & zwicky ( 1934 ) based on theoretical arguments , but had to wait until the 1970s for observational support , provided by the remarkable discoveries of the crab and vela pulsars in their respective supernova remnants ( snrs ) .
the properties of these pulsars were found to be uniquely explained in the context of rapidly rotating , magnetized neutron stars emitting beamed non - thermal radiation ..
Please generate the next two sentences of the article | their fast rotation rates and large magnetic fields ( @xmath2 g ) are consistent with those of a main - sequence star collapsed to ns dimension and density .
a fast period essentially precluded all but a ns hypothesis and thus provided direct evidence for the reality of nss ( see shapiro & teukolsky 1983 for a brief history and intro to ns physics ) . |
4,076 | Suppose that you have an abstract for a scientific paper: we propose an alternative scheme for nonreciprocal light propagation in two coupled cavities system , in which a two - level quantum emitter is coupled to one of the optical microcavities .
for the case of parity - time ( ) symmetric system ( i.e. , active - passive coupled cavities system ) , the cavity gain can significantly enhance the optical nonlinearity induced by the interaction between a quantum emitter and cavity field beyond weak - excitation approximation .
the giant optical nonlinearity results in the non - lossy nonreciprocal light propagation with high isolation ratio in proper parameters range . in addition , our calculations show that nonreciprocal light propagation will not be affected by the unstable output field intensity caused by optical bistability and we can even switch directions of nonreciprocal light propagation by appropriately adjusting the system parameters . .
And you have already written the first three sentences of the full article: achieving rapid development in integrated photonic circuits depends on the all - optical elements , which are essential for high - speed processing of light signals .
nonreciprocal light propagation is an indispensable common trait for some optical elements , such as optical diodes , optical isolator , circulator , etc .
for example , the optical diode permits the light transport in only one direction but not the opposite direction ..
Please generate the next two sentences of the article | the successful design of nonreciprocal light propagation devices relies on the breaking of the time - reversal symmetry .
thus , nonreciprocal light propagation is inherently difficult , even in theory because of the time - reversal symmetry of light - matter interaction @xcite . |
4,077 | Suppose that you have an abstract for a scientific paper: motivated by the recent exact solution of the _ stationary - state _ kardar - parisi - zhang ( kpz ) statistics by imamura & sasamoto ( phys .
rev .
lett . * 108 * , 190603 ( 2012 ) ) , as well as a precursor experimental signature unearthed by takeuchi ( phys
. rev .
lett . * 110 * , 210604 ( 2013 ) ) , we establish here the universality of these phenomena , examining scaling behaviors of directed polymers in a random medium , the stochastic heat equation with multiplicative noise , and kinetically roughened kpz growth models .
we emphasize the value of cross kpz - class universalities , revealing crossover effects of experimental relevance .
finally , we illustrate the great utility of kpz scaling theory by an optimized numerical analysis of the ulam problem of random permutations .
extremal paths through random energy landscapes ,
i.e. , directed polymers in random media " ( dprm ) , have long been a topic of great interest to statistical physicists , condensed matter theorists , and mathematicians alike @xcite . in two dimensions ,
the exact limit distributions of the dprm problem @xcite are of the celebrated tracy - widom ( tw ) type @xcite , best known perhaps from random matrix theory @xcite , as well as the famous ulam problem of random permutations @xcite .
nevertheless , in the bulk , the statistics of these extremal trajectories remains a challenging , rich , and quite difficult problem @xcite . in all dimensions , however , the constrained free - energy @xmath0 of these directed , extremal paths is dictated by the stochastic partial differential equation @xcite of kardar , parisi , & zhang ( kpz ) : @xmath1 where @xmath2 and @xmath3 are system - dependent parameters , the last setting the strength of the _ additive _ stochastic noise @xmath4 .
rigorous mathematical approaches , by contrast , have focussed on the related stochastic heat equation ( she ) with _ multiplicative _ noise , obtained from kpz via a hopf - cole transformation , @xmath5=@xmath6 ; here ,....
And you have already written the first three sentences of the full article: many thanks to k. a. takeuchi for numerous fruitful exchanges regarding our work and for providing his png skewness splines & 1 + 1 kpz class experimental data .
we re very grateful , as well , to m. prhofer for making available the tw - gue & goe traces , and to t. imamura for kindly sharing his numerical rendering of the baik - rains f@xmath10 limit distribution . 10 for early , bedrock kpz developments ,
see : t. halpin - healy & y .- c ..
Please generate the next two sentences of the article | zhang , phys .
rep . * 254 * , 215 ( 1995 ) ; j. krug , adv . |
4,078 | Suppose that you have an abstract for a scientific paper: the structure of the boundary hilbert - space and the condition that amplitudes behave appropriately under compositions determine the face amplitude of a spinfoam theory . in quantum gravity
the face amplitude turns out to be simpler than originally thought . .
And you have already written the first three sentences of the full article: a spinfoam sum over a given two - complex @xmath0 , formed by faces @xmath1 joining along edges @xmath2 in turn meeting at vertices @xmath3 , is defined by the expression z_= _ j_f , i_e _ f d_j_f _ v a_v(j_f , i_e ) , [ z ] where @xmath4 is the vertex amplitude " and @xmath5 is the face amplitude " .
the sum is over an assignment @xmath6 of an irreducible representation of a compact group @xmath7 to each face @xmath1 and of an intertwiner @xmath8 to each edge @xmath2 of the two - complex .
the expression is often viewed as a possible foundation for a background independent quantum theory of gravity @xcite . in particular ,.
Please generate the next two sentences of the article | a vertex amplitude @xmath4 that might define a quantum theory of gravity has been developed in @xcite and is today under intense investigation ( see @xcite ) .
but what about the measure factor " given by the face amplitude @xmath5 ? what determines it ? |
4,079 | Suppose that you have an abstract for a scientific paper: we are studying a variety of semileptonic decays of heavy - light mesons in an effort to improve the determination of the heavy - quark standard - model ckm matrix elements .
our fermion action is a novel , improved `` fat '' clover action that promises to reduce problems with exceptional configurations .
dynamical sea quarks are included in a mixed approach , _
i.e. _ we use staggered sea quarks and fat - clover valence quarks . here
we report preliminary results . .
And you have already written the first three sentences of the full article: we are studying the semileptonic decays @xmath0 , @xmath1 , @xmath2 , @xmath3 , and @xmath4 and the corresponding decays with a strange spectator quark . for a companion study of purely leptonic decays , see @xcite . the ckm matrix element @xmath5 , for example
, is obtained from the differential semileptonic decay rate for @xmath6 at total leptonic four - momentum @xmath7 @xcite : @xmath8 the unknown hadronic form factor @xmath9 is to be determined in lattice gauge theory from the matrix element of the weak vector current @xmath10 , @xmath11
since the heavy - light meson decays involve light quarks , it is important to choose an @xmath12 lattice fermion implementation with good chiral properties . to this end.
Please generate the next two sentences of the article | we have been experimenting with an action proposed by degrand , hasenfratz , and kovcs @xcite , which introduces , in effect , a cutoff - dependent form factor at the quark - gluon vertex to suppress lattice artifacts at the level of the cutoff .
the action is the usual clover action but with a gauge background constructed by replacing the usual gauge links by ape - smoothed links @xcite with coefficient @xmath13 for the forward link and @xmath14 for the sum of staples . |
4,080 | Suppose that you have an abstract for a scientific paper: we investigate the primordial scalar perturbations in the thermal dissipative inflation where the radiation component ( thermal bath ) persists and the density fluctuations are thermally originated .
the perturbation generated in this model is hybrid , i.e. it consists of both adiabatic and isocurvature components .
we calculate the fractional power ratio ( @xmath0 ) and the correlation coefficient ( @xmath1 ) between the adiabatic and the isocurvature perturbations at the commencing of the radiation regime .
since the adiabatic / isocurvature decomposition of hybrid perturbations generally is gauge - dependent at super - horizon scales when there is substantial energy exchange between the inflaton and the thermal bath , we carefully perform a proper decomposition of the perturbations .
we find that the adiabatic and the isocurvature perturbations are correlated , even though the fluctuations of the radiation component is considered uncorrelated with that of the inflaton .
we also show that both @xmath0 and @xmath2 depend mainly on the ratio between the dissipation coefficient @xmath3 and the hubble parameter @xmath4 during inflation .
the correlation is positive ( @xmath5 ) for strong dissipation cases where @xmath6 , and is negative for weak dissipation instances where @xmath7 .
moreover , @xmath0 and @xmath2 in this model are not independent of each other .
the predicted relation between @xmath0 and @xmath1 is consistent with the wmap observation .
other testable predictions are also discussed . .
And you have already written the first three sentences of the full article: the recently released data of the wilkinson microwave anisotropy probe ( wmap ) confirmed the earlier cobe - dmr s observation about the deficiency in fluctuation power at the largest angular scales @xcite .
the amount of quadrupole and octopole modes of the cmb temperature fluctuations is anomalously low if compared to the prediction of the @xmath8cdm model .
it implies that the initial density perturbations are significantly suppressed on scales equal to or larger than the hubble radius ..
Please generate the next two sentences of the article | models of structure formation with a cut - off power spectrum of perturbation on large scales provide a better fit to the cmb temperature fluctuations .
the most likely cut - off wavelength derived from the wmap data @xcite actually is the same as that determined by the cobe - dmr @xcite . |
4,081 | Suppose that you have an abstract for a scientific paper: we give the first examples of groups which admit a tame combing with linear radial tameness function with respect to any choice of finite presentation , but which are not minimally almost convex on a standard generating set .
namely , we explicitly construct such combings for thompson s group @xmath0 and the baumslag - solitar groups @xmath1 with @xmath2 . in order to make this construction for thompson s group @xmath0
, we significantly expand the understanding of the cayley complex of this group with respect to the standard finite presentation .
in particular we describe a quasigeodesic set of normal forms and combinatorially classify the arrangements of 2-cells adjacent to edges that do not lie on normal form paths . .
And you have already written the first three sentences of the full article: this paper has two goals : to study the relationships between the hierarchies of convexity conditions and tame combing conditions on a cayley complex corresponding to a given group , and to significantly expand the understanding of the cayley complex of thompson s group @xmath0 with respect to the standard finite presentation with two generators and two relators .
several notions of almost convexity for groups have been developed in geometric group theory , from the most restrictive property defined by cannon to the weakest notion of minimal almost convexity introduced by kapovich . for a group @xmath3 with finite generating set @xmath4 , almost convexity conditions for different classes of functions measure , in terms of the given function , how close balls in the cayley graph for @xmath5 are to being convex sets ( see section [ sub : ac ] for the formal definition ) .
results of thiel and elder and hermiller , respectively , show that cannon s almost convexity and minimal almost convexity , respectively , are not quasi - isometry invariants ..
Please generate the next two sentences of the article | mihalik and tschantz introduced the notion of a tame 1-combing of a 2-complex , and in particular of the cayley complex of a group presentation , in the context of studying properties of 3-manifolds .
hermiller and meier refined the definition of tame combing to differentiate between types of tameness functions , analogously to almost convexity conditions . for a group @xmath3 with finite presentation @xmath6 , |
4,082 | Suppose that you have an abstract for a scientific paper: we prove the conley conjecture for a closed symplectically aspherical symplectic manifold : a hamiltonian diffeomorphism of a such a manifold has infinitely many periodic points .
more precisely , we show that a hamiltonian diffeomorphism with finitely many fixed points has simple periodic points of arbitrarily large period .
this theorem generalizes , for instance , a recent result of hingston establishing the conley conjecture for tori . .
And you have already written the first three sentences of the full article: [ sec : intro ] we show that a hamiltonian diffeomorphism of a closed symplectically aspherical manifold has infinitely many periodic points .
more precisely , we prove that such a diffeomorphism with finitely many fixed points has simple periodic points of arbitrarily large period .
for tori , this fact , recently established by hingston , @xcite , was conjectured by conley , @xcite and is frequently referred to as the _ conley conjecture_. ( see also @xcite and references therein for similar results for hamiltonian diffeomorphisms and homeomorphisms of surfaces . ) the proof given here uses some crucial ideas from @xcite , but is completely self - contained ..
Please generate the next two sentences of the article | the main result of the paper is [ thm : main ] let @xmath0 be a hamiltonian diffeomorphism of a closed symplectically aspherical manifold @xmath1 .
assume that the fixed points of @xmath2 are isolated . |
4,083 | Suppose that you have an abstract for a scientific paper: we present a series of quantum states that are characterized by dark solitons of the nonlinear schrdinger equation ( i.e. the gross - pitaevskii equation ) for the one - dimensional ( 1d ) bose gas interacting through the repulsive delta - function potentials .
the classical solutions satisfy the periodic boundary conditions and we simply call them classical dark solitons . through exact solutions
we show corresponding aspects between the states and the solitons in the weak coupling case : the quantum and classical density profiles completely overlap with each other not only at an initial time but also at later times over a long period of time , and they move together with the same speed in time ; the matrix element of the bosonic field operator between the quantum states has exactly the same profiles of the square amplitude and the phase as the classical complex scalar field of a classical dark soliton not only at the initial time but also at later times , and the corresponding profiles move together for a long period of time .
we suggest that the corresponding properties hold rigorously in the weak coupling limit . furthermore , we argue that the lifetime of the dark soliton - like density profile in the quantum state becomes infinitely long as the coupling constant approaches zero , by comparing it with the quantum speed limit time .
thus , we call the quantum states _ quantum dark soliton states_. .
And you have already written the first three sentences of the full article: the experimental technique of trapped one - dimensional atomic gases @xcite has now become a fundamental tool for revealing nontrivial effects in quantum many - body systems @xcite . for the interacting bose gas in one dimension ( 1d ) , the first set of exact results goes back to the pioneering work of girardeau @xcite on the impenetrable bose gas where the strong interacting limit is considered .
the 1d bose gas interacting with the delta - function potentials , i.e. the lieb - liniger ( ll ) model , gives a solvable model for interacting bosons in 1d @xcite , where it is integrable even when the interaction parameter is generic .
for the impenetrable bose gas which corresponds to the tonks - girardeau ( tg ) limit , i.e. the strong interacting limit of the ll model , the one - body reduced density matrix is derived and successfully expressed in terms of the determinant of a fredholm operator @xcite ..
Please generate the next two sentences of the article | the exact result is followed by several important developments in mathematical physics @xcite .
furthermore , dynamical correlation functions of the ll model are now systematically derived @xcite . |
4,084 | Suppose that you have an abstract for a scientific paper: we show how hybrid inflation can be successfully realized in a supersymmetric model with gauge group @xmath0 . by including a non - renormalizable superpotential term , we generate an inflationary valley along which @xmath1 is broken to the standard model gauge group .
thus , catastrophic production of the doubly charged magnetic monopoles , which are predicted by the model , can not occur at the end of inflation .
the results of the cosmic background explorer can be reproduced with natural values ( of order @xmath2 ) of the relevant coupling constant , and symmetry breaking scale of @xmath1 of the order of @xmath3 gev .
the spectral index of density perturbations lies between unity and @xmath4 .
moreover , the @xmath5-term is generated via a peccei - quinn symmetry and proton is practically stable .
baryogenesis in the universe takes place via leptogenesis . the low deuterium abundance constraint on the baryon asymmetry ,
the gravitino limit on the reheat temperature and the requirement of almost maximal @xmath6 mixing from superkamiokande can be simultaneously met with @xmath7 , @xmath8 and heaviest dirac neutrino mass determined from the large angle msw resolution of the solar neutrino problem , the superkamiokande results and @xmath9 symmetry respectively . ba-99 - 82 , ftuam-99 - 42 , +
ic/99/187 , ut - stpd-1/00 . 0.3 cm * inflation and monopoles in supersymmetric + 0.15 cm @xmath10 * 0.35 cm r. jeannerot@xmath11 , s. khalil@xmath12 , g. lazarides@xmath13 and q. shafi@xmath14 + + + + + + .
And you have already written the first three sentences of the full article: after the recent discovery of neutrino oscillations by the superkamiokande experiment @xcite , supersymmetric ( susy ) models with left - right symmetric gauge groups have attracted a great deal of attention .
these models provide a natural framework for implementing the seesaw mechanism @xcite which explains the existence of the small neutrino masses .
the implications of these models have been considered in ref.@xcite , in the case of the gauge group @xmath15 , and in ref.@xcite for the susy pati - salam ( ps ) @xcite model based on the gauge group @xmath16 ..
Please generate the next two sentences of the article | it was shown that they lead to a constraint version of the minimal supersymmetric standard model ( mssm ) .
0.25 cm recently , it was demonstrated @xcite that the n=1 susy ps model can emerge as the effective four dimensional limit of brane models from type i string theory . |
4,085 | Suppose that you have an abstract for a scientific paper: we study surface states of 1d photonic crystals using a semiclassical coupled wave theory . both te and tm modes are treated .
we derive analytic approximations that clarify the systematics of the dispersion relations , and the roles of the various parameters defining the crystal . .
And you have already written the first three sentences of the full article: photonic crystals are artificial low - loss dielectric structures with periodic modulation of refractive index , which have attracted considerable attention in the last two decades . due to bragg reflection
, electromagnetic ( optical ) waves can not propagate through such structures in certain directions , at certain frequencies .
hence , photonic crystals can control the propagation of electromagnetic waves in novel ways , with obvious application to dielectric mirrors , dielectric waveguides , and dielectric laser cavities . as a way to efficiently inject light into a photonic crystal ( pc ) waveguide.
Please generate the next two sentences of the article | , it has recently been proposed to use surface electromagnetic waves ( sew)@xcite . in those papers , the photonic crystal was a two dimensional array of rods , of infinite length normal to the plane of incidence .
instead , we have studied sew on a semi - infinite one - dimensional ( 1d ) photonic crystal sketched in fig . |
4,086 | Suppose that you have an abstract for a scientific paper: we study six - dimensional ( 6d ) su(6 ) supersymmetric models where the doublet - triplet splitting , quark - lepton mass relations and gaugino - mediated supersymmetry breaking are taken into account .
we find that effective 4d gauge coupling constants have highly nontrivial behavior between two compactification scales .
it is shown that realistic patterns of yukawa coupling constants are obtained for valid values of parameters and that hierarchical numbers are generated via suppression by extra - dimensional effects .
hip-2008 - 09/th + * gauge and yukawa couplings in 6d supersymmetric su(6 ) models * nobuhiro uekusa _ department of physics , university of helsinki + and helsinki institute of physics , + p.o .
box 64 , fin-00014 helsinki , finland _
+ _ e - mail _ : [email protected] .
And you have already written the first three sentences of the full article: approaching grand unification and supersymmetry in higher dimensions has been an intriguing possibility .
one of the problems to be solved in grand unification is the doublet - triplet splitting . in the four - dimensional ( 4d ) minimal su(5 )
grand unified model , an adjoint higgs field is responsible for breaking the unified gauge group to the standard model gauge group , whereas a fundamental higgs field leads to breaking electroweak symmetry ..
Please generate the next two sentences of the article | this fundamental higgs field includes a color - triplet higgs field as well as the weak - doublet higgs field under the standard model gauge group . at tree level ,
the triplet and doublet higgs fields acquire their masses depending on the parameters in the potential of the original adjoint and fundamental higgs fields . |
4,087 | Suppose that you have an abstract for a scientific paper: let @xmath0 be a sequence of polynomials whose generating function @xmath1 is the reciprocal of a bivariate polynomial @xmath2 .
we show that in the three cases @xmath3 , @xmath4 and @xmath5 , where @xmath6 and @xmath7 are any polynomials in @xmath8 with complex coefficients , the roots of @xmath0 lie on a portion of a real algebraic curve whose equation is explicitly given .
the proofs involve the @xmath9-analogue of the discriminant , a concept introduced by mourad ismail . .
And you have already written the first three sentences of the full article: in this paper we study the root distribution of a sequence of polynomials satisfying one of the following three - term recurrences : @xmath10 with certain initial conditions and @xmath11 polynomials in @xmath8 with complex coefficients . for the study of the root distribution of other sequences of polynomials that satisfy three - term recurrences , see @xcite and @xcite .
in particular , we choose the initial conditions so that the generating function is @xmath12 where @xmath3 , @xmath4 , or @xmath5 .
we notice that the root distribution of @xmath0 will be the same if we replace @xmath13 in the numerator by any monomial @xmath14 ..
Please generate the next two sentences of the article | if @xmath14 is not a monomial , the root distribution will be different .
the quadratic case @xmath3 is not difficult and it is also mentioned in @xcite . |
4,088 | Suppose that you have an abstract for a scientific paper: * abstract * we show that the basic categorical concept of an @xmath0-algebra as derived from the theory of segal s @xmath1-sets provides a unifying description of several constructions attempting to model an algebraic geometry over the absolute point .
it merges , in particular , the approaches using monods , semirings and hyperrings as well as the development by means of monads and generalized rings in arakelov geometry .
the assembly map determines a functorial way to associate an @xmath0-algebra to a monad on pointed sets .
the notion of an @xmath0-algebra is very familiar in algebraic topology where it also provides a suitable groundwork to the definition of topological cyclic homology .
the main contribution of this paper is to point out its relevance and unifying role in arithmetic , in relation with the development of an algebraic geometry over symmetric closed monoidal categories . .
And you have already written the first three sentences of the full article: the notion of an @xmath0-algebra ( _ i.e. _ algebra over the sphere spectrum ) is well - known in homotopy theory ( _ cf . _ _ e.g. _ @xcite ) : in the categorical form used in this paper and implemented by the concept of a discrete @xmath1-ring , it was formalized in the late 90 s .
@xmath0-algebras are also intimately related to the theory of brave new rings ( first introduced in the 80 s ) and of functors with smash products ( fsp ) for spectra in algebraic topology ( _ cf .
_ @xcite ) ..
Please generate the next two sentences of the article | the goal of this article is to explain how the implementation of the notion of an @xmath0-algebra in arithmetic , in terms of segal s @xmath1-rings , succeeds to unify several constructions pursued in recent times aimed to define the notion of absolute algebra " . in particular
, we refer to the development , for applications in number theory and algebraic geometry , of a suitable framework apt to provide a rigorous meaning to the process of taking the limit of geometry over finite fields @xmath2 as @xmath3 . in our previous work |
4,089 | Suppose that you have an abstract for a scientific paper: in social situations with which evolutionary game is concerned , individuals are considered to be heterogeneous in various aspects . in particular , they may differently perceive the same outcome of the game owing to heterogeneity in idiosyncratic preferences , fighting abilities , and positions in a social network . in such a population , an individual may imitate successful and similar others , where similarity refers to that in the idiosyncratic fitness function .
i propose an evolutionary game model with two subpopulations on the basis of multipopulation replicator dynamics to describe such a situation . in the proposed model ,
pairs of players are involved in a two - person game as a well - mixed population , and imitation occurs within subpopulations in each of which players have the same payoff matrix .
it is shown that the model does not allow any internal equilibrium such that the dynamics differs from that of other related models such as the bimatrix game .
in particular , even a slight difference in the payoff matrix in the two subpopulations can make the opposite strategies to be stably selected in the two subpopulations in the snowdrift and coordination games .
keywords : evolutionary game ; replicator dynamics ; homophily ; cooperation .
And you have already written the first three sentences of the full article: a basic assumption underlying many evolutionary and economic game theoretical models is that individuals are the same except for possible differences in the strategy that they select .
in fact , a population of individuals involved in ecological or social interaction is considered to be heterogeneous .
for example , different individuals may have different fighting abilities or endowments @xcite , occupy different positions in contact networks specifying the peers with whom the game is played @xcite , or have different preferences over the objective outcome of the game ..
Please generate the next two sentences of the article | the last situation is succinctly represented by the battle of the sexes game in which a wife and husband prefer to go to watch opera and football , respectively , whereas their stronger priority is on going out together @xcite ( the battle of the sexes game here is different from the one that models conflicts between males and females concerning parental investment as described in @xcite ) . in behavioral game experiments ,
the heterogeneity of subjects is rather a norm than exceptions ( e.g. , @xcite ) . |
4,090 | Suppose that you have an abstract for a scientific paper: we consider the energy - supercritical harmonic heat flow from @xmath0 into the @xmath1-sphere @xmath2 with @xmath3 . under an additional assumption of 1-corotational symmetry
, the problem reduces to the one dimensional semilinear heat equation @xmath4 we construct for this equation a family of @xmath5 solutions which blow up in finite time via concentration of the universal profile @xmath6 where @xmath7 is the stationary solution of the equation and the speed is given by the quantized rates @xmath8.\ ] ] the construction relies on two arguments : the reduction of the problem to a finite - dimensional one thanks to a robust universal energy method and modulation techniques developed by merle , raphal and rodnianski @xcite for the energy supercritical nonlinear schrdinger equation and by raphal and schweyer @xcite for the energy critical harmonic heat flow , then we proceed by contradiction to solve the finite - dimensional problem and conclude using the brouwer fixed point theorem
. moreover , our constructed solutions are in fact @xmath9 codimension stable under perturbations of the initial data . as a consequence
, the case @xmath10 corresponds to a stable type ii blowup regime .
t. ghoul@xmath11 , s. ibrahim@xmath12 and v. t. nguyen@xmath11 .
And you have already written the first three sentences of the full article: we consider the harmonic map heat flow which is defined as the negative gradient flow of the dirichlet energy of maps between manifolds . indeed ,
if @xmath13 is a map from @xmath14 to a compact riemannian manifold @xmath15 , with second fundamental form @xmath16 , then @xmath13 solves @xmath17 we assume that the target manifold is the @xmath1-sphere @xmath18 .
then , becomes @xmath19 we will study the problem under an additional assumption of 1-corotational symmetry , namely that a solution of takes the form @xmath20 under this ansatz , the problem reduces to the one dimensional semilinear heat equation @xmath21 where @xmath22 $ ] ..
Please generate the next two sentences of the article | the set of solutions to is invariant by the scaling symmetry @xmath23 the energy associated to is given by @xmath24(t ) = \int_0^{+\infty } \left(|\partial_r u|^2 + \frac{(d-1)}{r^2}\sin^2(u)\right)r^{d-1}dr,\ ] ] which satisfies @xmath25 = \lambda^{d-2}{\mathcal{e}}[u].\ ] ] the criticality of the problem is reflected by the fact that the energy is left invariant by the scaling property when @xmath26 , hence , the case @xmath27 corresponds to the energy supercritical case .
the problem is locally wellposed for data which are close in @xmath28 to a uniformly continuous map ( see koch and lamm @xcite ) or in @xmath29 by wang @xcite . actually , eells and sampson @xcite introduced the harmonic map heat flow as a process to deform any smooth map @xmath30 into a harmonic map via . |
4,091 | Suppose that you have an abstract for a scientific paper: we propose a new constrained level - set method for semi - automatic image segmentation .
the method allows to specify which parts of the image lie inside respectively outside the segmented objects .
such an a - priori information can be expressed in terms of upper and lower constraints prescribed for the level - set function .
constraints have the same meaning as the initial seeds of the graph - cuts based methods for image segmentation .
a numerical approximation scheme is based on the complementary - finite volumes method combined with the projected successive over - relaxation method adopted for solving range bounds constrained linear complementarity problems .
the advantage of the constrained level - set method is demonstrated on several artificial images as well as on cardiac mri data .
linear complementarity , image processing , segmentation , level - set method , projected successive over - relaxation method , graph cuts 90c33 , 35k55 , 35k52 , 53c44 , 74s10 , 74g15 .
And you have already written the first three sentences of the full article: _ the level - set methods _ for the image segmentation have been studied and applied during the last two decades .
the level - set method applied in the image segmentation is typically an iterative method .
the segmentation starts with an initial curve @xmath0 representing an initial guess for the segmented object and it is evolved towards the segmented object by means of a suitable geometric law taking into account the direction to the segmented object and also the curvature of evolved curves . loosely speaking ,.
Please generate the next two sentences of the article | the better the initial guess is , the better and faster the segmentation process is .
this is profitable for processing of time sequences where the final segmentation of one frame may serve as the initial guess for the next frame . |
4,092 | Suppose that you have an abstract for a scientific paper: we present late - time _ hubble space telescope _ ( _ hst _ ) images of the site of supernova ( sn ) 2009ip taken almost 3 yr after its bright 2012 luminosity peak .
sn 2009ip is now slightly fainter in broad filters than the progenitor candidate detected by _ hst _ in 1999 .
the current source continues to be dominated by ongoing late - time csm interaction that produces strong h@xmath0 emission and a weak pseudo - continuum , as found previously for 1 - 2 yr after explosion .
the intent of these observations was to search for evidence of recent star formation in the local ( @xmath11kpc ; 10 ) environment around sn 2009ip , in the remote outskirts of its host spiral galaxy ngc 7259 .
we can rule out the presence of any massive star - forming complexes like 30 dor or the carina nebula at the sn site or within a few kpc .
if the progenitor of sn 2009ip was really a 50 - 80 @xmath2 star as archival _ hst _ images suggested , then it is strange that there is no sign of this type of massive star formation anywhere in the vicinity .
a possible explanation is that the progenitor was the product of a merger or binary mass transfer , rejuvenated after a lifetime that was much longer than 4 - 5 myr , allowing its natal h ii region to have faded
. a smaller region like the orion nebula would be an unresolved but easily detected point source .
this is ruled out within @xmath11.5 kpc around sn 2009ip , but a small h ii region could be hiding in the glare of sn 2009ip itself . later
images after a few more years have passed are needed to confirm that the progenitor candidate is truly gone and to test for the presence of a small h ii region or cluster at the sn position .
[ firstpage ] circumstellar matter stars : evolution stars : winds , outflows supernovae : general supernovae : individual ( 2009ip ) .
And you have already written the first three sentences of the full article: the class of type iin supernovae ( sne iin hereafter ) , whose narrow h lines indicate strong interaction with dense circumstellar material ( csm ) , have challenged our understanding of stellar evolution and death .
their dense h - rich csm , progenitor instability , and high initial masses inferred from various clues suggest a link to the class of luminous blue variables ( lbvs ) , which are not supposed to be anywhere near core collapse in the standard scenario of massive single - star evolution ( see @xcite for a general review ) .
among well - studied examples of sne iin , the explosion of sn 2009ip in mid-2012 ( note that its discovery in 2009 was deemed to be a sn impostor ) is one of the most interesting , with by far the best observational characterization of a directly detected progenitor among any sn in history ( even sn 1987a ) ..
Please generate the next two sentences of the article | it had a ( presumably ) quiescent progenitor star candidate detected in archival _ hubble space telescope _
( _ hst _ ) images , with a luminosity that implied a very high initial mass of at least 50 - 60 @xmath2 @xcite . |
4,093 | Suppose that you have an abstract for a scientific paper: the contribution presents an analysis of a rate - independent non - local damage model , recently proposed by @xcite .
an analytical as well as numerical solution of a simple one - dimensional bifurcation problem is performed , demonstrating that , for the elementary localization test , the model is free of pathological features . [ [ keywords ] ] keywords + + + + + + + + damage , non - locality , energetic solution , discretization in time , bifurcation .
And you have already written the first three sentences of the full article: in engineering mechanics , _ damage _ is understood as a load - induced evolution of microstructural defects , resulting in a reduced macroscopic material integrity .
the phenomenological constitutive models of damage incorporate the irreversible phenomena by reducing the secant modulus of elasticity depending on the _ internal _ damage variable .
since the seminal contribution of @xcite , it has been well - understood that such description within the framework of local ( i.e. scale - free ) continuum mechanics leads to an ill - posed problem , resulting in localization of damage growth into an arbitrarily small region . as a remedy to this pathology.
Please generate the next two sentences of the article | , a plethora of non - local rate - independent continuum theories , based on integral , explicit and implicit gradient approaches , has been proposed to introduce an _ internal length scale _ into the description , see e.g. ( * ? ? ?
* chapter 26 ) for a representative overview . despite a significant increase in objectivity offered by the enhanced continuum theories , the non - local damage formulations often suffer from the fact that the non - local variables are introduced into the model in an ad - hoc fashion , thus violating basic constraints of thermodynamics . |
4,094 | Suppose that you have an abstract for a scientific paper: we present methods to improve the energy resolution of single channel , room - temperature cadmium - zinc - telluride ( czt ) detectors .
a new preamplifier design enables the acquisition of the actual transient current from the crystals and straightforward data analysis methods yield unprecedented energy resolution for our test - detectors . these consist of an ev - capture plus crystal as standard and 1 cm cube frisch collar crystals created in - house from low - grade coplanar grid detectors .
energy resolutions of 1.9% for our collar detectors and 0.8% for the ev crystal at 662 kev were obtained . the latter compares
favourably to the best existing energy resolution results from pixel detectors . .
And you have already written the first three sentences of the full article: the motivation to research cdznte ( czt ) detectors originates from participation in the cobra experiment @xcite , a proposed massive ( several hundred kg ) array of czt crystals for double - beta decay research .
taking into account a typical mass of merely a few grams for each crystal , several tens of thousands of crystals will eventually have to be operated reliably over several years .
naturally , such a set - up would become vastly more practical by utilising simple ways to mount and operate individual crystals in the array ..
Please generate the next two sentences of the article | single - channel readout for each crystal as opposed to coplanar grid detectors is considered to be an attractive option .
already the reduction of wiring close to the crystals by a factor of two would be highly significant in this case . |
4,095 | Suppose that you have an abstract for a scientific paper: a generalized stochastic method for projecting out the ground state of the quantum many - body schrdinger equation on curved manifolds is introduced .
this random - walk method is of wide applicability to any second order differential equation ( first order in time ) , in any spatial dimension .
the technique reduces to determining the proper `` quantum corrections '' for the euclidean short - time propagator that is used to build up their path - integral monte carlo solutions . for particles with fermi statistics
the `` fixed - phase '' constraint ( which amounts to fixing the phase of the many - body state ) allows one to obtain stable , albeit approximate , solutions with a variational property .
we illustrate the method by applying it to the problem of an electron moving on the surface of a sphere in the presence of a dirac magnetic monopole . .
And you have already written the first three sentences of the full article: the importance and difficulty of solving models of interacting quantum particles is hard to overstate .
it is well known that the correlated motion of those particles gives rise to a wide variety of physical phenomena at different length and time scales , spanning disciplines like chemistry , condensed matter , nuclear , and high energy physics .
novel complex structures can emerge as a consequence of the competing multiple - length scales in the problem ..
Please generate the next two sentences of the article | nonetheless , only a reduced set of interacting problems admits exact closed form solutions @xcite and the use of numerical techniques becomes essential if one is looking for accurate solutions not subjected to uncontrolled approximations . among those techniques , the statistical methods @xcite offer the potential to study systems with large number of degrees of freedom , reducing the computational complexity from exponential to polynomial growth
this scaling behavior is particularly relevant when one recognizes that most of the interesting phenomena in many - body physics occurs in the thermodynamic limit @xcite . |
4,096 | Suppose that you have an abstract for a scientific paper: light vector mesons are among the most informative probes to understand the strongly coupled quark gluon plasma created at rhic .
the suppression of light mesons at high transverse momentum , compared to expectations from scaled @xmath0 results , reflects the properties of the strongly interacting matter formed .
the @xmath1-meson is one of the probes whose systematic measurement in @xmath0 , @xmath2 and @xmath3 collisions can provide useful information about initial and final state effects on particle production .
the mass , width and branching ratio of the @xmath1-meson decay in the di - kaon and di - electron decay channels could be modified in @xmath3 collisions due to the restoration of chiral symmetry in the qgp .
the phenix experiment at rhic has measured @xmath1-meson production in various systems ranging form @xmath0 , @xmath2 to @xmath3 collisions via both its di - electron and di - kaon decay modes .
a summary of phenix results on invariant spectra , nuclear modification factor and elliptic flow of the @xmath1-meson are presented here . .
And you have already written the first three sentences of the full article: the @xmath1- meson plays a unique role in the study of the hot and dense medium created in relativistic heavy - ion collisions .
it is is the lightest bound state of hidden strangeness @xmath4 , has a small interaction with other non - strange hadrons and hence carries information from the early partonic stages of the system evolution . comparing the elliptic flow ( @xmath5 ) of @xmath1 to the @xmath5 of other multistrange hadrons ( @xmath6 and @xmath7 ) or particles composed of lighter quarks ( @xmath8 and @xmath9 ) or heavier charm quark , provides information about the partonic collectivity of the medium .
furthermore the @xmath1 can provide important information on particle production mechanisms , since it is a meson but has a mass similar to @xmath10 and @xmath11 baryons ..
Please generate the next two sentences of the article | the measurement of its nuclear modification factor , @xmath12 adds to the picture of particle suppression and its dependence on particle mass and composition supporting hydrodynamics and recombination models .
the @xmath1 can also be sensitive to the restoration of chiral symmetry . |
4,097 | Suppose that you have an abstract for a scientific paper: in this paper , we consider an interior transmission eigenvalue ( ite ) problem on some compact @xmath0-riemannian manifolds with smooth boundary .
in particular , we do not assume that two domains are diffeomorphic , but we impose some conditions of riemannian metrics and indices of refraction on the boundary .
then we prove the discreteness of the set of ites , the existence of infinitely many ites , and its weyl type lower bound .
our problem is non - coercive .
however , the argument by lakshtanov and vainberg @xcite which reduces the problem to the elliptic one using the dirichlet - to - neumann map , is valid for manifolds . .
And you have already written the first three sentences of the full article: we consider two connected and compact @xmath1-riemannian manifolds @xmath2 and @xmath3 with @xmath0-boundaries @xmath4 and @xmath5 , respectively .
we assume @xmath6 and @xmath7 . throughout of the present paper ,
we assume that * ( a-1 ) * @xmath8 and @xmath9 have a common boundary @xmath10 . @xmath11 is a disjoint union of a finite number of connected and closed components ..
Please generate the next two sentences of the article | the metrics satisfy @xmath12 on @xmath11 .
we will add some other assumptions for @xmath13 and @xmath14 in a neighborhood of the boundary later . |
4,098 | Suppose that you have an abstract for a scientific paper: we explore the nonlinear coupling of the three scissors modes of an anisotropic bose - einstein condensate .
we show that only when the frequency of one of the scissors modes is twice the frequency of another scissors mode , these two modes can be resonantly coupled and a down conversion can occur .
we perform the calculation variationally using a gaussian trial wave function .
this enables us to obtain simple analytical results that describe the oscillation and resonance behaviour of the two coupled modes .
23 cm -1 cm 15 cm .
And you have already written the first three sentences of the full article: similar to monopole and quadrupole breathing modes of a gaseous bose - einstein condensate , scissors modes were first studied theoretically and subsequently observed experimentally .
the scissors modes are , however , rather special since they directly manifest the superfluid behavior of these atomic gases . moreover , the recent experimental studies appear to show a resonance behavior between two coupled scissors modes @xcite . from a theoretical point of view
this is interesting because a linear - response calculation can neither account for the coupling nor for the resonance behavior ..
Please generate the next two sentences of the article | therefore , a first step towards an explanation of these experimental observations is to perform a calculation that goes beyond linear - response theory and accurately takes into account the mean - field interaction that couples the scissors and breathing modes . in this paper
we present a simple variational method for calculating the frequencies of these various modes and their couplings beyond the linear - response . |
4,099 | Suppose that you have an abstract for a scientific paper: for a class of martingales , this paper provides a framework on the uniform consistency with broad applicability .
the main condition imposed is only related to the conditional variance of the martingale , which holds true for stationary mixing time series , stationary iterated random function , harris recurrent markov chains and @xmath0 processes with innovations being a linear process . using the established results , this paper investigates the uniform convergence of the nadaraya
watson estimator in a non - linear cointegrating regression model .
our results not only provide sharp convergence rate , but also the optimal range for the uniform convergence to be held .
this paper also considers the uniform upper and lower bound estimates for a functional of harris recurrent markov chain , which are of independent interests . .
And you have already written the first three sentences of the full article: let @xmath1 with @xmath2 , be a sequence of random vectors .
a common functional of interests @xmath3 of @xmath4 is defined by @xmath5,\qquad x\in r^d,\ ] ] where @xmath6 is a certain sequence of positive constants and @xmath7 is a real function on @xmath8 .
such functionals arise in non - parametric estimation problems , where @xmath9 may be a kernel function @xmath10 or a squared kernel function @xmath11 and the sequence @xmath12 is the bandwidth used in the non - parametric regression ..
Please generate the next two sentences of the article | the uniform convergence of @xmath3 in the situation that the @xmath4 satisfy certain stationary conditions was studied in many articles .
liero @xcite , peligrad @xcite and nze and doukhan @xcite considered the uniform convergence over a fixed compact set , while masry @xcite , bosq @xcite and fan and yao @xcite gave uniform results over an unbounded set . |
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