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3,500 | Suppose that you have an abstract for a scientific paper: we consider the slow nonlinear diffusion equation subject to a constant absorption rate and construct local self - similar solutions for reversing ( and anti - reversing ) interfaces , where an initially advancing ( receding ) interface gives way to a receding ( advancing ) one .
we use an approach based on invariant manifolds , which allows us to determine the required asymptotic behaviour for small and large values of the concentration .
we then ` connect ' the requisite asymptotic behaviours using a robust and accurate numerical scheme . by doing so , we are able to furnish a rich set of self - similar solutions for both reversing and anti - reversing interfaces .
nonlinear diffusion equation , slow diffusion , strong absorption , self - similar solutions , invariant manifolds , reversing interface , anti - reversing interface .
And you have already written the first three sentences of the full article: we address reversing and anti - reversing properties of interfaces in the following one - dimensional slow diffusion equation with strong absorption @xmath0 where @xmath1 is a positive function , _
e.g. _ , a concentration of some species , and @xmath2 and @xmath3 denote space and time , respectively . restricting the exponents to the ranges @xmath4 and @xmath5 corresponds to the slow diffusion and strong absorption cases respectively
. interfaces sometimes termed ` contact lines ' by fluid dynamicists correspond to the points on the @xmath2-axis , where regions for positive solutions for @xmath1 are connected with the regions where @xmath1 is identically zero . the initial data @xmath6 is assumed to be compactly supported ..
Please generate the next two sentences of the article | the motion of the interfaces is determined from conditions that require the function @xmath1 be continuous and the flux of @xmath1 through the interface to be zero @xcite . in the presence of slow diffusion ( @xmath4 ) , the interfaces of compactly supported solutions have a finite propagation speed @xcite . in the presence of strong absorption ( @xmath5 )
, the solution vanishes for all @xmath2 after some finite time , which is referred to as finite - time extinction @xcite . |
3,501 | Suppose that you have an abstract for a scientific paper: diffuse reflectance spectroscopy is a powerful technique to predict soil properties .
it can be used _ in situ _ to provide data inexpensively and rapidly compared to the standard laboratory measurements .
because most spectral data bases contain air - dried samples scanned in the laboratory , field spectra acquired _ in situ _ are either absent or rare in calibration data sets .
however , when models are calibrated on air - dried spectra , prediction using field spectra are often inaccurate .
we propose a framework to calibrate partial least squares models when field spectra are rare using synthetic minority oversampling technique ( smote ) .
we calibrated a model to predict soil organic carbon content using air - dried spectra spiked with synthetic field spectra .
the root mean - squared error of prediction decreased from 6.18 to 2.12 mg g@xmath0 and @xmath1 increased from @xmath20.53 to 0.82 compared to the model calibrated on air - dried spectra only .
= 1 diffuse reflectance spectroscopy , soil , partial least squares , calibration , smote .
And you have already written the first three sentences of the full article: diffuse reflectance spectroscopy in the visible and near - infrared range ( vis - nir drs ) has proved to be useful to assess various soil properties @xcite .
it can be employed to provide more data rapidly and inexpensively compared to classical laboratory analysis .
therefore , drs is increasingly used for vast soil surveys in agriculture and environmental research @xcite . recently.
Please generate the next two sentences of the article | , several studies have shown the applicability of vis - nir drs _ in situ _ as a proximal soil sensing technique @xcite . to predict soil properties from soil spectra ,
a model is calibrated , often using partial least squares ( pls ) regression . however , when calibration is based on air - dried spectra collected under laboratory conditions , predictions of soil properties from field spectra tend to be less accurate @xcite . |
3,502 | Suppose that you have an abstract for a scientific paper: the class of compact steep - spectrum sources is dominated by double - lobed objects ( 70% ) .
the remaining 30% are jet - dominated objects , with the jet brightened either by doppler boosting or by interaction with the ambient media .
we show that there is both observational and statistical evidence in favour of an interaction between jets and dense gas clouds .
such an interaction should happen in the narrow line regions .
the images of four csss observed by us with vlbi are also presented
. these sources do show large bent jets in the first kpc from the nucleus . .
And you have already written the first three sentences of the full article: the class of compact steep - spectrum sources ( csss ) has been discussed by many authors ( e.g. pearson et al .
1985 ; fanti it et al.1990 ) .
it is now generally believed that csss are physically small objects with sub - galactic dimensions , whose structure and sizes are possibly affected by the ambient gas in the central regions of the parent optical objects ..
Please generate the next two sentences of the article | double - lobed sources represent @xmath0 of the objects in a sample of csss ( fanti et al .
1995 ) selected from the 3cr catalogue ( laing et al . 1983 ) and from the peacock & wall ( 1982 ) catalogue for a linear size @xmath1kpc , spectral index @xmath2 ( s@xmath3 ) and radio power @xmath4whz@xmath5 at 178mhz for the 3cr or @xmath6whz@xmath5 at 2.7ghz ( @xmath7kmsec@xmath5mpc@xmath5 and @xmath8 ) . |
3,503 | Suppose that you have an abstract for a scientific paper: the current status of the 2mrad crossing angle layout for the ilc is reviewed .
the scheme developed in the uk and france is described and the performance discussed for a tev machine . secondly , the scheme developed at slac and bnl is then studied and modified for a tev machine .
we find that both schemes can handle the higher energy beam with modifications , and share many common features . .
And you have already written the first three sentences of the full article: in this article , we describe the recent development of the 2mrad horizontal crossing angle scheme for the ilc . to date , two parallel designs have emerged : the first coming from the uk and france and the second from slac and bnl .
we shall describe both schemes here , although they share many common features and are now being developed in parallel under the unified slac - bnl - uk - france task force collaboration .
the work presented focuses on the performance at 1 tev ..
Please generate the next two sentences of the article | the benefits of the scheme are well documented @xcite : for small crossing angles , the loss of luminosity is small ( crab correction may not be necessary and it may be possible to partially correct this loss by exploiting the finite @xmath0 at the ip for local chromaticity correction lattices ) , no electrostatic separators or kicker magnets are needed and the conditions are improved for physics ( e.g. better forward coverage ) . a known weakness of this scheme is however its more difficult conditions for extracting cleanly the spent disrupted and energy - degraded beam , in comparison with larger crossing - angle schemes where separate magnetic channels can be used for in - and outgoing beams .
the work presented here covers the designs developed at slac , bnl , the uk and france . in section [ euroscheme ] |
3,504 | Suppose that you have an abstract for a scientific paper: within an adiabatic approximation to the three - body coulomb system , we study the strength of the leading order conformaly invariant attractive dipole interaction produced when a slow charged particle @xmath0 ( with mass @xmath1 ) is captured by the first excited state of a dimer [ with individual masses and charges @xmath2 ) and ( @xmath3 ) ] .
the approach leads to a universal mass - charge critical condition for the existence of three - body level condensation , @xmath4}>\left|{q_1}/(24\ ; q_3)\right|$ ] , as well as the ratio between the geometrically scaled energy levels .
the resulting expressions can be relevant in the analysis of recent experimental setups with charged three - body systems , such as the interactions of excitons , or other matter - antimatter dimers , with a slow charged particle . .
And you have already written the first three sentences of the full article: in view of the actual experimental possibilities , we recall some general characteristics of three - body charged systems with arbitrary masses and two different charges , in order to derive the charge - mass dependence of the leading order strength of the attractive dipole interaction produced by a bound two - body subsystem ( with individual charges @xmath5 and @xmath6 ) in the third particle with charge @xmath0 .
we start our investigation by considering the old and well - known case of the interaction of a positronium ( @xmath7 , a bound - state of an electron @xmath8 and a positron @xmath9 , where @xmath10 is the absolute value of the electron charge ) with a spectator electron .
this is the ionized negative positronium ( @xmath11 ) ..
Please generate the next two sentences of the article | early calculations , by wheeler in 1946 @xcite , have already predicted a bound state for such system , confirmed by mills in 1981 @xcite .
further investigations on the properties of @xmath12 system @xcite , as well as on other coulombic three - body systems , since 1960 s up to recent years @xcite , have also been motivated by the increasing interest in matter - antimatter interactions @xcite . |
3,505 | Suppose that you have an abstract for a scientific paper: we investigate a @xmath0 dimensional generalization of the schroedinger - newton equations , which purport to describe quantum state reduction as resulting from gravitational effects . for a single particle ,
the system is a combination of the schroedinger and poisson equations modified so that the probability density of the wavefunction is the source of the potential in the schroedinger equation . for
spherically symmetric wavefunctions , a discrete set of energy eigenvalue solutions emerges for dimensions @xmath1 , accumulating at @xmath2 . invoking heisenberg s uncertainty principle to assign timescales of collapse correspoding to each energy eigenvalue , we find that these timescales may vary by many orders of magnitude depending on dimension .
for example , the time taken for the wavefunction of a free neutron in a spherically symmetric state to collapse is many orders of magnitude longer than the age of the universe , whereas for one confined to a box of picometer - sized cross - sectional dimensions the collapse time is about two weeks .
* studies of the schroedinger - newton equations in @xmath0 dimensions * + r. melko and r.b .
mann + dept . of physics ,
university of waterloo waterloo , ont n2l 3g1 , canada + pacs numbers : 04.62 , 02.90 , 03.65 , 03.65 g , 04.20 + + .
And you have already written the first three sentences of the full article: in quantum mechanics , objects are described by wavefunctions .
these take the form of complex superpositions of various evolutionary alternatives , or states .
although successful in describing many aspects of the quantum world , this picture often leads to troubling interpretations when extrapolated to the macroscopic level ..
Please generate the next two sentences of the article | one issue that has suffered long debate is the fact that one never observes a superposition of states .
rather , one only observes a system s _ basic _ or _ stationary _ states . |
3,506 | Suppose that you have an abstract for a scientific paper: electron spin diffusion is investigated in monolayer mos@xmath0 in the absence of external electric and magnetic fields .
the electron - impurity scattering , which is shown to play a negligible role in spin relaxation in time domain in this material , has a marked effect on the in - plane spin diffusion due to the anisotropic spin precession frequency in the spatial domain . with the electron - impurity and inter - valley electron - phonon scatterings separately included in the scattering term
, we study the intra- and inter - valley diffusion processes of the in - plane spins by analytically solving the kinetic spin bloch equations . the intra - valley process is found to be dominant in the in - plane spin diffusion , in contrast to the case of spin relaxation in time domain , where the inter - valley process can be comparable to or even more important than the intra - valley one . for the intra - valley process , we find that the in - plane spin diffusion is suppressed with the increase of impurity density but effectively enhanced by increasing electron density in both the degenerate and nondegenerate limits .
we also take into account the electron - electron coulomb scattering in the intra - valley process .
interestingly , we find that in the nondegenerate limit , the intra - valley spin diffusion length presents an opposite trend in the electron density dependence compared to the one with only electron - impurity scattering . .
And you have already written the first three sentences of the full article: monolayer mos@xmath0 has attracted much attention due to its promising applications in electronics,@xcite optoelectronics,@xcite valleytronics@xcite and also spintronics.@xcite for the application of spintronic devices , the suitable spin lifetime and spin diffusion length are required.@xcite this indicates the importance of the investigations on the spin relaxation and spin diffusion in this material .
very recently , spin relaxation has been studied in monolayer mos@xmath0.@xcite wang and wu@xcite calculated the in - plane spin relaxation time of electrons due to the dyakonov - perel@xcite ( dp ) and elliot - yafet@xcite ( ey ) mechanisms with the intra- and inter - valley processes included .
they pointed out that the dp mechanism , which results from the inhomogeneous broadening@xcite together with any scattering process , dominates the spin relaxation ..
Please generate the next two sentences of the article | the inhomogeneous broadening is from the spin - orbit coupling ( soc ) of the conduction band@xcite @xmath1\hat{\bf z } , \label{soctime}\ ] ] where the @xmath2-axis is perpendicular to the monolayer mos@xmath0 plane ; @xmath3 , @xmath4 and @xmath5 are the strengths of the soc ; @xmath6 represents the k(k@xmath7 ) valley .
the first term of the soc , which is momentum independent , only induces the inter - valley dp spin relaxation whereas the last two terms are momentum dependent , which lead to the intra- and inter - valley spin relaxation processes . |
3,507 | Suppose that you have an abstract for a scientific paper: we give a detailed and rigorous picture of the mesoscopic conductance fluctuations in the deep insulating regime ( dir ) within the nguyen , spivak and shklovskii model including spin - orbit coupling ( so ) .
without so , we find that fluctuations of the log - conductance are persistent above a saturation field @xmath0 , where one has that the log - conductance is approximately a stationary random process .
in contrast , in the so case the saturation field @xmath1 is negligible and the stationarity is well realized .
we find non - vanishing disorder fluctuations of the field average of the log - conductance as a quantitative measure of the lack of ergodicity in the mean square sense . to this fact
, a weak decaying behavior of the correlation function , even weaker in the case of so is established on the relevant field scale of the model , one flux quantum per plaquette .
this finding corroborate the behavior of the fluctuations of the field average of the log - conductance and permit us to invoke slutski s theorem to conclude that the whole stochastic process defined by the log - conductance is non - ergodic in the mean square sense in both cases . as a consequence the commonly used criterion to test the ergodicity based on the equivalence of the variance in disorder and the variance in the field is not fulfilled . using the replica approach , we derive the weak localization analogs of the cooperon and diffuson which permits us to analyze in qualitative form the decaying behavior of the correlation function .
our predictions agree qualitatively and semi - quantitative with experiments in the dir . .
And you have already written the first three sentences of the full article: the nature of fluctuations in both the metallic state @xcite,@xcite , and in disordered insulators @xcite , @xcite , has been a matter of interest for both theoretical and experimental studies .
whereas in the metallic regime the basic aspects of fluctuations have been elucidated , in the regime of hopping transport the nature of fluctuations is still an open field .
the deep insulating regime , dir , where transport occurs via variable range hopping ( vrh ) , is defined as the regime where the localization length is the smallest scale compared to the elastic mean free path and hopping lengths , i.e. , @xmath2 respectively@xcite ..
Please generate the next two sentences of the article | coherence effects are possible in this regime because phase breaking events occur at the hopping length@xcite , which is larger than @xmath3 .
important signatures of quantum interference in disordered insulators are the classic magneto - fingerprints , or reproducible fluctuations in the conductance with magnetic field , and a low field positive magneto - conductance . |
3,508 | Suppose that you have an abstract for a scientific paper: this paper is the first to review the scene flow estimation field to the best of our knowledge , which analyzes and compares methods , technical challenges , evaluation methodologies and performance of scene flow estimation .
existing algorithms are categorized in terms of scene representation , data source , and calculation scheme , and the pros and cons in each category are compared briefly . the datasets and evaluation protocols are enumerated , and the performance of the most representative methods is presented .
a future vision is illustrated with few questions arisen for discussion .
this survey presents a general introduction and analysis of scene flow estimation . .
And you have already written the first three sentences of the full article: scene flow is a three - dimensional motion field of the surface in world space , or in other words , it shows the three - dimensional displacement vector of each surface point between two frames . as most computer vision issues are , scene flow estimation is essentially an ill - posed energy minimization problem with three unknowns .
prior knowledge in multiple aspects is required to make the energy function solvable with just a few pairs of images .
hence , it s essential to fully make use of information from the data source and to weigh different prior knowledge for a better performance ..
Please generate the next two sentences of the article | the paper attempts to reveal clues by providing a comprehensive literature survey in this field .
scene flow is first introduced by vedula in 1999 @xcite and has made constant progress over the years . |
3,509 | Suppose that you have an abstract for a scientific paper: now creation of big catalogs of galaxies for measurement of baryon acoustic oscillation ( bao ) is actively conducted . existing and planned in the near future surveys
are directed on the range of red shifts of z@xmath02
. however , some popular models of dark energy ( de ) give the maximum deviation from @xmath1cdm at z>2 therefore we investigated sensitivity of hypothetical high redshift surveys to the model of de .
we have found that with the increase of the number density of detected galaxies at z>2 high redshift observations may give better constraints of de parameters . .
And you have already written the first three sentences of the full article: several cosmological observations show that our universe is expanding with an acceleration@xcite .
this fact can be interpreted as a dominance of the energy of the unknown nature , so called _ dark energy _
( de)@xcite ..
Please generate the next two sentences of the article | the main feature of this energy consists of negative pressure that leads to an accelerated expansion .
the standard cosmological scenario implies that order of 75% of the total energy density is present in the form of de . |
3,510 | Suppose that you have an abstract for a scientific paper: we propose a collective opinion formation model with a so - called confirmation bias .
the confirmation bias is a psychological effect with which , in the context of opinion formation , an individual in favor of an opinion is prone to misperceive new incoming information as supporting the current belief of the individual .
our model modifies a bayesian decision - making model for single individuals [ m. rabin and j. l. schrag , q. j. econ . *
114 * , 37 ( 1999 ) ] for the case of a well - mixed population of interacting individuals in the absence of the external input .
we numerically simulate the model to show that all the agents eventually agree on one of the two opinions only when the confirmation bias is weak .
otherwise , the stochastic population dynamics ends up creating a disagreement configuration ( also called polarization ) , particularly for large system sizes .
a strong confirmation bias allows various final disagreement configurations with different fractions of the individuals in favor of the opposite opinions .
pacs numbers : : 87.23.ge , 02.50.ey , 02.50.le 0 .
And you have already written the first three sentences of the full article: there are various models of collective opinion formation in which agents modify their opinions according to interaction with other agents @xcite . opinion formation is a dynamic process : for example , interaction between agents makes their opinions approach each other .
an important problem in opinion dynamics is to examine when an agreement ( i.e. , consensus ) among all the agents occurs .
complete agreement is rarely observed in the real world @xcite ..
Please generate the next two sentences of the article | however , it is an established fact that opinion dynamics under the voter model , a classical opinion model in statistical physics and probability theory , inevitably reaches agreement in finite populations @xcite .
the majority rule model has a similar feature @xcite . |
3,511 | Suppose that you have an abstract for a scientific paper: we investigate baryon - baryon interactions with strangeness @xmath0 and isospin @xmath1 system from lattice qcd . in order to solve this system ,
we prepare three types of baryon - baryon operators ( @xmath2 , @xmath3 and @xmath4 ) for the sink and construct three source operators diagonalizing the @xmath5 correlation matrix . combining of the prepared sink operators with the diagonalized source operators , we obtain nine effective nambu - bethe - salpeter ( nbs ) wave functions .
the @xmath5 potential matrix is calculated by solving the coupled - channel schrdinger equation .
the flavor @xmath6 breaking effects of the potential matrix are also discussed by comparing with the results of the @xmath6 limit calculation .
our numerical results are obtained from three sets of @xmath7 flavor qcd gauge configurations provided by the cp - pacs / jlqcd collaborations .
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And you have already written the first three sentences of the full article: completion of the knowledge of the generalized nuclear force , which includes not only the nucleon - nucleon ( nn ) interaction but also hyperon - nucleon ( yn ) and hyperon - hyperon ( yy ) interactions , brought the deeper understanding of atomic nuclei , structure of neutron stars and supernova explosions .
however it is hard to know the properties of the yn and yy interactions because their scattering data in free - space are scarce . recently
a method to extract the @xmath8 potential through the nbs wave function from lattice qcd simulations has been proposed in @xcite ..
Please generate the next two sentences of the article | the obtained potential is found to have desirable features , such as attractive well at long and medium distances , and the central repulsive core at short distance @xcite .
further applications have been done in refs . |
3,512 | Suppose that you have an abstract for a scientific paper: in this paper , the author considers the numerical computation of cva for large systems by mote carlo methods .
he introduces two types of stochastic mesh methods for the computations of cva . in the first method ,
stochastic mesh method is used to obtain the future value of the derivative contracts . in the second method ,
stochastic mesh method is used only to judge whether future value of the derivative contracts is positive or not .
he discusses the rate of convergence to the real cva value of these methods .
jel classification : c63 , g12 mathematical subject classification(2010 ) 65c05 , 60g40 keywords : computational finance , option pricing , malliavin calculus , stochastic mesh method , cva .
And you have already written the first three sentences of the full article: the credit valuation adjustment ( cva ) is , by definition , the difference between the risk - free portfolio value and the true portfolio value that takes into account default risk of the counterparty . in other words , cva is the market value of counterparty credit risk .
after the financial crisis in 2007 - 2008 , it has been widely recognized that even major financial institutions may default .
therefore , the market participants has become fully aware of counterparty credit risk . in order to reflect the counterparty credit risk in the price of over - the - counter ( otc ) derivative transactions ,.
Please generate the next two sentences of the article | cva is widely used in the financial institutions today .
although duffie - huang @xcite has already introduced the basic idea of cva in 1990 s , several people reconsidered the theory of cva related to collateralized derivatives ( cf . |
3,513 | Suppose that you have an abstract for a scientific paper: many statistical procedures , including goodness - of - fit tests and methods for independent component analysis , rely critically on the estimation of the entropy of a distribution . in this paper ,
we seek entropy estimators that are efficient in the sense of achieving the local asymptotic minimax lower bound . to this end
, we initially study a generalisation of the estimator originally proposed by @xcite , based on the @xmath0-nearest neighbour distances of a sample of @xmath1 independent and identically distributed random vectors in @xmath2 .
when @xmath3 and provided @xmath4 ( as well as other regularity conditions ) , we show that the estimator is efficient ; on the other hand , when @xmath5 , a non - trivial bias precludes its efficiency regardless of the choice of @xmath0 .
this motivates us to consider a new entropy estimator , formed as a weighted average of kozachenko leonenko estimators for different values of @xmath0 .
a careful choice of weights enables us to obtain an efficient estimator in arbitrary dimensions , given sufficient smoothness .
in addition to the new estimator proposed and theoretical understanding provided , our results also have other methodological implications ; in particular , they motivate the prewhitening of the data before applying the estimator and facilitate the construction of asymptotically valid confidence intervals of asymptotically minimal width . .
And you have already written the first three sentences of the full article: the concept of entropy plays a central role in information theory , and has found a wide array of uses in other disciplines , including statistics , probability and combinatorics .
the _ ( differential ) entropy _ of a random vector @xmath6 with density function @xmath7 is defined as @xmath8 where @xmath9 .
it represents the average information content of an observation , and is usually thought of as a measure of unpredictability . in statistical contexts , it is often the estimation of entropy that is of primary interest , for instance in goodness - of - fit tests of normality @xcite or uniformity @xcite , tests of independence @xcite , independent component analysis @xcite and feature selection in classification @xcite ..
Please generate the next two sentences of the article | see , for example , @xcite and @xcite for other applications and an overview of nonparametric techniques , which include methods based on sample spacings ( in the univariate case ) , histograms and kernel density estimates , among others .
the estimator of @xcite is particularly attractive as a starting point , both because it generalises easily to multivariate cases , and because , since it only relies on the evaluation of @xmath0th - nearest neighbour distances , it is straightforward to compute . to introduce this estimator , |
3,514 | Suppose that you have an abstract for a scientific paper: molecular motors perform active movements along cytoskeletal filaments and drive the traffic of organelles and other cargo particles in cells .
in contrast to the macroscopic traffic of cars , however , the traffic of molecular motors is characterized by a finite walking distance ( or run length ) after which a motor unbinds from the filament along which it moves .
unbound motors perform brownian motion in the surrounding aqueous solution until they rebind to a filament .
we use variants of driven lattice gas models to describe the interplay of their active movements , the unbound diffusion , and the binding / unbinding dynamics .
if the motor concentration is large , motor - motor interactions become important and lead to a variety of cooperative traffic phenomena such as traffic jams on the filaments , boundary - induced phase transitions , and spontaneous symmetry breaking in systems with two species of motors . if the filament is surrounded by a large reservoir of motors , the jam length , i.e.
, the extension of the traffic jams is of the order of the walking distance .
much longer jams can be found in confined geometries such as tube - like compartments . .
And you have already written the first three sentences of the full article: the traffic of vesicles , organelles , protein complexes , messenger rna , and even viruses within the cells of living beings is driven by the molecular motors of the cytoskeleton which move along cytoskeletal filaments in a directed fashion @xcite .
there are three large classes of cytoskeletal motors , kinesins and dyneins which move along microtubules , and myosins which move along actin filaments .
these motors use the free energy released from the hydrolysis of adenosinetriphosphate ( atp ) , which represents their chemical fuel , for active movement and to perform mechanical work ..
Please generate the next two sentences of the article | they move in discrete steps in such a way that one molecule of atp is used per step .
typical step sizes are @xmath0 nm , typical motor velocities are in the range of @xmath1m / sec . since the interior of cells is quite crowded and motors are strongly attracted by the filaments , which leads to relatively large motor densities along the filaments , it is interesting to study the collective traffic phenomena which arise from motor motor interactions , in particular the formation of traffic jams due to the mutual exclusion of motors from filament sites . to study these cooperative phenomena |
3,515 | Suppose that you have an abstract for a scientific paper: the fundamental problem of the calculus of variations on time scales concerns the minimization of a delta - integral over all trajectories satisfying given boundary conditions . in this paper
we prove the second euler - lagrange necessary optimality condition for optimal trajectories of variational problems on time scales . as an example of application of the main result
, we give an alternative and simpler proof to the noether theorem on time scales recently obtained in [ j. math .
anal .
appl . 342
( 2008 ) , no . 2 , 12201226 ] .
* mathematics subject classification 2000 : * 49k05 , 39a12 .
* keywords : * calculus of variations ; optimal control ; euler - lagrange , dubois - reymond , and second erdmann necessary optimality conditions ; noether s theorem ; time scales . .
And you have already written the first three sentences of the full article: the calculus on time scales is a recent field , introduced by bernd aulbach and stefan hilger in 1988 @xcite , that unifies and extends difference and differential equations into a single theory @xcite .
a time scale is a model of time , and the new theory has found important applications in several fields that require simultaneous modeling of discrete and continuous data , in particular in the calculus of variations @xcite , control theory @xcite , and optimal control @xcite .
other areas of application include engineering , biology , economics , finance , and physics @xcite . the present work is dedicated to the study of problems of calculus of variations on an arbitrary time scale @xmath0 . as particular cases , one gets the standard calculus of variations @xcite by choosing @xmath1 ; the discrete - time calculus of variations @xcite by choosing @xmath2 ; and the @xmath3-calculus of variations @xcite by choosing @xmath4 , @xmath5 . in section [ sec : prel : ts ] we briefly present the necessary notions and results of time scales , delta derivatives , and delta integrals ..
Please generate the next two sentences of the article | let @xmath0 be a given time scale with at least three points , @xmath6 , and @xmath7 be of class @xmath8 .
suppose that @xmath9 and @xmath10 . |
3,516 | Suppose that you have an abstract for a scientific paper: cu@xmath0bi@xmath1se@xmath2 has drawn much attention as the leading candidate to be the first topological superconductor and the realization of coveted majorana particles in a condensed matter system .
however , there has been increasing controversy about the nature of its superconducting phase .
this study sheds light on present ambiguity in the normal state electronic state , by providing a complete look at the quantum oscillations in magnetization in cu@xmath0bi@xmath1se@xmath2 at intense high fields up to 31 t .
our study focuses on the angular dependence of the quantum oscillation pattern in a low carrier concentration .
as magnetic field tilts from along the crystalline c - axis to ab - plane , the change of the oscillation period follows the prediction of the ellipsoidal fermi surface . as the doping level changes , the 3d fermi surface is found to transform into quasi - cylindrical at high carrier density .
such a transition is potentially a lifshitz transition of the electronic state in cu@xmath0bi@xmath1se@xmath2 . .
And you have already written the first three sentences of the full article: topological superconductor is a novel phase of matter that has been theoretically predicted but yet to be experimentally verified . among topological materials ,
topological superconductivity is especially interesting because it is a platform to realize majorana particles - an elusive particle that is its own antiparticle .
furthermore , topological superconductors have been proposed as a platform for topological quantum computation ..
Please generate the next two sentences of the article | @xcite the robustness of the topological surface states makes this avenue an attractive alternative to traditional methods for realizing quantum computation .
@xcite a topological superconductor must have a full superconducting gap in the bulk with odd parity pairing , and the fermi surface must enclose an odd number of time reversal invariant momenta in the brillouin zone , i.e. the fermi surface must contain an odd number of high symmetry points such as @xmath3 , z , x , etc . |
3,517 | Suppose that you have an abstract for a scientific paper: we present the @xmath0smic @xmath1yman-@xmath2 @xmath3ransfer code ( @xmath4 ) , a massively parallel monte - carlo radiative transfer code , to simulate lyman-@xmath2 ( ly@xmath2 ) resonant scattering through neutral hydrogen as a probe of the first galaxies .
we explore the interaction of centrally produced ly@xmath2 radiation with the host galactic environment .
ly@xmath2 photons emitted from the luminous starburst region escape with characteristic features in the line profile depending on the density distribution , ionization structure , and bulk velocity fields .
for example , anisotropic ionization exhibits a tall peak close to line centre with a skewed tail that drops off gradually .
idealized models of first galaxies explore the effect of mass , anisotropic hii regions , and radiation pressure driven winds on ly@xmath2 observables .
we employ mesh refinement to resolve critical structures .
we also post - process an _ ab initio _ cosmological simulation and examine images captured at various distances within the 1 mpc@xmath5 comoving volume .
finally , we discuss the emergent spectra and surface brightness profiles of these objects in the context of high-@xmath6 observations .
the first galaxies will likely be observed through the red damping wing of the ly@xmath2 line .
observations will be biased toward galaxies with an intrinsic red peak located far from line centre that reside in extensive hii super bubbles , which allows hubble flow to sufficiently redshift photons away from line centre and facilitate transmission through the intergalactic medium . even with gravitational lensing to boost the luminosity this preliminary work indicates that ly@xmath2 emission from stellar clusters within haloes of @xmath7 is generally too faint to be detected by the _ james webb space telescope _ ( _ jwst _ ) .
[ firstpage ] lyman-@xmath2 emission
radiative transfer resonant scattering line : profiles cosmology : theory galaxies : formation galaxies : high - redshift .
And you have already written the first three sentences of the full article: observations of lyman-@xmath2 ( ly@xmath2 ) sources are a powerful probe of the high - redshift universe ( e.g. * ? ? ?
* ; * ? ? ?
* ; * ? ? ?.
Please generate the next two sentences of the article | * ; * ? ? ?
in particular , the prominence of the ly@xmath2 line at @xmath8 allows for spectroscopic confirmation of redshift measurements of individual distant galaxies . |
3,518 | Suppose that you have an abstract for a scientific paper: we describe the physics of an articulated toy with an internal source of energy provided by a spiral spring .
the toy is a funny low cost kangaroo which jumps and rotates .
the study consists of a mechanical and a thermodynamical analysis which makes use of the newton and center of mass equations , the rotational equations and the first law of thermodynamics .
this amazing toy provides a nice demonstrative example how new physics insights can be brought about when links with thermodynamics are established in the study of mechanical systems . 0.6 cm plus 1pt minus 1pt = 1500 * the physics of articulated toys a + jumping and rotating kangaroo * 0.4 cm j. gmez@xmath0 , m. fiolhais@xmath1 0.1 cm _
@xmath2 departamento de fsica aplicada _
+ _ universidad de cantabria _ + _ e-39005 santander , spain _ + 0.1 cm _
@xmath3 departamento de fsica and centro de fsica computacional
_ + _ universidade de coimbra _ + _ p-3004 - 516 coimbra , portugal _ .
And you have already written the first three sentences of the full article: toys can be helpful in increasing students motivation in the classroom . in presentations for popularizing and communicating science to more general audiences
, they can also help increasing the appreciation and interest in the physical science , sometimes in such a way that everyone ( especially non - scientists ) will probably grasp some fundamental concepts .
however , they should be used with care : the physical description of some toys is not so easy @xcite , even in the framework of simplified models , and their usefulness is sometimes limited ..
Please generate the next two sentences of the article | but , at least for motivation purposes , they are always valuable @xcite . in this paper
we describe the motion of a toy that , due to an internal source of energy , jumps while rotates . |
3,519 | Suppose that you have an abstract for a scientific paper: index coded psk modulation over an awgn broadcast channel , for a given index coding problem ( icp ) is studied . for a chosen index code and an arbitrary mapping ( of broadcast vectors to psk signal points ) , we have derived a decision rule for the maximum likelihood ( ml ) decoder .
the message error performance of a receiver at high snr is characterized by a parameter called _ * psk index coding gain ( psk - icg)*_. the psk - icg of a receiver is determined by a metric called _ * minimum inter - set distance*_. for a given icp with an order of priority among the receivers , and a chosen @xmath0-psk constellation we propose an algorithm to find _ * ( index code , mapping ) * _ pairs , each of which gives the best performance in terms of psk - icg of the receivers .
no other pair of index code ( of length @xmath1 with @xmath0 broadcast vectors ) and mapping can give a better psk - icg for the highest priority receiver .
also , given that the highest priority receiver achieves its best performance , the next highest priority receiver achieves its maximum gain possible and so on in the specified order of priority . .
And you have already written the first three sentences of the full article: network coding technique has significantly improved the performance of communication networks , and has been studied extensively in the past two decades .
index coding problem ( icp ) can be considered as a special case of network coding problem @xcite .
icp has emerged as an important topic of recent research due to its applications in many of the practically relevant problems including that in satellite networks , topological interference management , wireless caching and cache enabled cloud radio access networks for 5 g cellular systems ..
Please generate the next two sentences of the article | the noiseless index coding problem with side information was first studied in @xcite as an informed - source coding - on - demand ( iscod ) problem , in which a central server ( sender ) wants to broadcast data blocks to a set of clients ( receivers ) which already has a proper subset of the data blocks .
the problem is to minimize the data that must be broadcast , so that each receiver can derive its required data blocks . |
3,520 | Suppose that you have an abstract for a scientific paper: we investigate the equilibrium properties of self - gravitating magnetized clouds with polytropic equations of state with negative index @xmath0 .
in particular , we consider scale - free isopedic configurations that have constant dimensionless spherical mass - to - flux ratio @xmath1 and that may constitute `` pivotal '' states for subsequent dynamical collapse to form groups or clusters of stars . for given @xmath2 , equilibria with smaller values of @xmath1 are more flattened , ranging from spherical configurations with @xmath3 to completely flattened states for @xmath4 . for a given amount of support provided by the magnetic field as measured by the dimensionless parameter @xmath5 , equilibria with smaller values of @xmath6
are more flattened .
however , logatropic ( defined by @xmath7 ) disks do not exist .
the only possible scale - free isopedic equilibria with logatropic equation of state are spherical uniformly magnetized clouds . .
And you have already written the first three sentences of the full article: the stage leading up to dynamic collapse of a magnetically subcritical cloud core to a protostar or a group of protostars is believed to be largely quasi - static , if the responsible process is ambipolar diffusion ( e.g. , mestel & spitzer 1956 , @xcite , @xcite , @xcite , @xcite ) . to describe the transition between quasi - static evolution by ambipolar diffusion and dynamical evolution by gravitational collapse
, @xcite introduced the idea of a pivotal state , with the scale - free , magnetostatic , density distribution approaching @xmath8 for an isothermal equation of state ( eos ) when the mass - to - flux ratio has a spatially constant value , a condition that @xcite and @xcite termed `` isopedic '' .
numerical simulations of the contraction of magnetized clouds justify the assumption of a nearly constant mass - to - flux ratio in the pivotal core .. outside the starred point , the mass - to - flux value exhibits greater variation , but this occurs only because @xcite impose starting values for the mass - to - flux in the envelope that are @xmath9 times the critical value ( see also figs . 4a and 8b in @xcite ) . such small ratios for the bulk of the mass of a molecular cloud are probably ruled out by the zeeman oh measurements summarized by crutcher ( 1998 ) . ] the small dense cores of molecular clouds that give rise to low - mass star formation are effectively isothermal ( @xcite ; @xcite ).
Please generate the next two sentences of the article | . the situation may be different for larger regions that yield high - mass or clustered star formation .
it has often been suggested that the eos relating the gas pressure @xmath10 to the mass density @xmath11 of interstellar clouds can be represented by a polytropic relation @xmath12 with negative index @xmath0 . |
3,521 | Suppose that you have an abstract for a scientific paper: we analyze data from five _ chandra _ observations of the spiral galaxy ngc 6946 and from three _ chandra _ observations of the irregular / spiral interacting galaxy pair ngc 4485/4490 , with an emphasis on investigating the long - term variability exhibited by the source populations .
we detect 90 point sources coincident with ngc 6946 down to luminosities of a few times @xmath0 , and 38 sources coincident with ngc 4485/90 down to a luminosity of @xmath1 .
twenty - five ( 15 ) sources in ngc 6946 ( ngc 4485/90 ) exhibit long - term ( i.e. , weeks to years ) variability in luminosity ; 11 ( 4 ) are transient candidates . the single ultraluminous x - ray source ( ulx ) in ngc 6946 and all but one of the eight ulxs in ngc 4485/90 exhibit long - term flux variability .
two of the ulxs in ngc 4485/90 have not been identified before as ultraluminous sources .
the widespread variability in both systems is indicative of the populations being dominated by x - ray binaries , and this is supported by the x - ray colors of the sources .
the distribution of colors among the sources indicates a large fraction of high - mass x - ray binaries in both systems .
the shapes of the x - ray luminosity functions of the galaxies do not change significantly between observations and can be described by power laws with cumulative slopes @xmath2 ( ngc 6946 ) and @xmath3 ( ngc 4485/90 ) . .
And you have already written the first three sentences of the full article: the systematic study of x - ray source populations in external galaxies first became possible with the _ einstein _ observatory in 1978 .
significant advances in the field were made with subsequent satellites such as _ rosat _ , but a giant leap forward has been taken with _
chandra_. with its subarcsecond spatial resolution and high sensitivity.
Please generate the next two sentences of the article | it is possible to resolve the vast majority of the luminous ( @xmath4 ) x - ray sources in galaxies out to distances of @xmath5 mpc .
in addition , the spectrometric capabilities of the _ chandra _ acis ccd detector allow spectral properties of sources to be extracted . |
3,522 | Suppose that you have an abstract for a scientific paper: we study the effects of the perturbation which violates the permutation symmetry of three majorana neutrinos but preserves the well known ( 23 ) interchange symmetry .
this is done in the presence of an arbitrary majorana phase @xmath0 which serves to insure the degeneracy of the three neutrinos at the unperturbed level . .
And you have already written the first three sentences of the full article: in the present paper , a particular approach to understanding lepton mixing , proposed in @xcite and further studied in @xcite , will be examined in more detail .
first , we briefly review the approach .
of course , the standard model interaction term for @xmath1 decay or @xmath2 includes the leptonic piece : @xmath3 the object @xmath4 is now known @xcite-@xcite to be a linear combination of neutrino mass eigenstates , @xmath5 : @xmath6 where , in a basis with the charged leptons diagonal , the full lepton mixing matrix is written as : @xmath7 as has been discussed by many authors @xcite-@xcite the results of neutrino oscillation experiments are ( neglecting possible phases to be discussed later ) consistent with the tribimaximal mixing " matrix : @xmath8 many different approaches have been used to explain the form of @xmath9 ..
Please generate the next two sentences of the article | natural",and often investigated one uses the parallel three generation structure of the fundamental fermion families as a starting point .
an underlying discrete symmetry @xmath10 , the permutation group on three objects , is then assumed . |
3,523 | Suppose that you have an abstract for a scientific paper: in the present paper , we mainly study the integrable semi - discretization of a multi - component short pulse equation .
firstly , we briefly review the bilinear equations for a multi - component short pulse equation proposed by matsuno ( j. math . phys . * 52 * 123705 ) and reaffirm its @xmath0-soliton solution in terms of pfaffians . then by using a bcklund transformation of the bilinear equations and defining a discrete hodograph ( reciprocal ) transformation ,
an integrable semi - discrete multi - component short pulse equation is constructed . meanwhile , its @xmath0-soliton solution in terms of pfaffians is also proved . .
And you have already written the first three sentences of the full article: the nonlinear schrdinger ( nls ) equation , as one of the universal equations that describe the evolution of slowly varying packets of quasi - monochromatic waves in weakly nonlinear dispersive media , has been very successful in many applications such as nonlinear optics and water waves @xcite .
the nls equation is integrable and can be solved by the inverse scattering transform @xcite . however , in the regime of ultra - short pulses where the width of optical pulse is in the order of femtosecond ( @xmath1 s ) , the nls equation becomes less accurate @xcite .
description of ultra - short processes requires a modification of going beyond the standard slow varying envelope approximation ( svea ) ..
Please generate the next two sentences of the article | recently , schfer and wayne derived a short pulse ( sp ) equation @xmath2 in attempting to describe the propagation of ultra - short optical pulses in nonlinear media @xcite . here , @xmath3 is a real - valued function , representing the magnitude of the electric field , the subscripts @xmath4 and @xmath5 denote partial differentiation .
it has been shown that the sp equation performs better than nls under this case @xcite . |
3,524 | Suppose that you have an abstract for a scientific paper: a representation is put forward for wave functions of quantum particles in periodic lattice potentials subjected to homogeneous time - periodic forcing , based on an expansion with respect to bloch - like states which embody both the spatial and the temporal periodicity .
it is shown that there exists a generalization of bloch s famous acceleration theorem which grows out of this representation , and captures the effect of a weak probe force applied in addition to a strong dressing force . taken together , these elements point at a `` dressing and probing '' strategy for coherent wave - packet manipulation , which could be implemented in present experiments with optical lattices . .
And you have already written the first three sentences of the full article: the so - called acceleration theorem for wave - packet motion in periodic potentials , formulated already in 1928 by bloch , @xcite has proven to be of outstanding value to solid - state physics for understanding the dynamics of bloch electrons within a semiclassical picture .
@xcite in its most - often used variant , this theorem states that if we consider an electronic wave packet in a spatially periodic lattice , which is centered in @xmath0 space around some wave vector @xmath1 , and if an external electric field @xmath2 is applied under single - band conditions , then this center wave vector evolves in time according to @xmath3 , with @xmath4 being the electronic charge .
perhaps its best - known application is the explanation of bloch oscillations of particles exposed to a homogeneous , constant force , @xcite which we recapitulate here in the simplest guise : take a particle in a one - dimensional tight - binding energy band @xmath5 , where @xmath6 is the band width and @xmath7 denotes the lattice period ..
Please generate the next two sentences of the article | assume that the particle s wave packet is centered around @xmath8 initially and subjected to a homogeneous force of strength @xmath9 .
then the acceleration theorem , now taking the form @xmath10 tells us @xmath11 , so that the packet moves through @xmath0 space at a constant rate . |
3,525 | Suppose that you have an abstract for a scientific paper: the thermodynamics of a scalar field with a quartic interaction is studied within the linear @xmath0 expansion ( lde ) method .
using the imaginary - time formalism the free energy is evaluated up to second order in the lde .
the method generates nonperturbative results that are then used to obtain thermodynamic quantities like the pressure .
the phase transition pattern of the model is fully studied , from the broken to the symmetry restored phase .
the results are compared with those obtained with other nonperturbative methods and also with ordinary perturbation theory .
the results coming from the two main optimization procedures used in conjunction with the lde method , the principle of minimal sensitivity ( pms ) and the fastest apparent convergence ( fac ) are also compared with each other and studied in which cases they are applicable or not .
the optimization procedures are applied directly to the free energy . .
And you have already written the first three sentences of the full article: phase transition phenomena in quantum field theories are typically of nonperturbative nature and thus naive perturbation theory based on an expansion in the coupling constant can not be employed .
this is clearly the case of phase changes at high temperatures , where perturbation theory becomes unreliable because powers of the coupling constant become surmounted by powers of the temperature @xcite .
problems with perturbation theory also happen in phenomena occurring close to critical points , because large fluctuations can emerge in the system due to infrared divergences , thus requiring nonperturbative methods as well in their studies ..
Please generate the next two sentences of the article | this is the case of studies involving second order phase transitions and also in weak first order phase transitions @xcite .
typical examples where these problems can manifest are in studies of symmetry changing phenomena in a hot and dense medium , a subject of interest in quantum chromodynamics ( qcd ) in the context of heavy - ion collision experiments , and also in studies of the early universe . |
3,526 | Suppose that you have an abstract for a scientific paper: i review the status of neutrino masses and mixings in the light of the solar and atmospheric neutrino data .
the result from the lsnd experiment and the possible role of neutrinos as hot dark matter are also included .
i also discuss the simplest schemes proposed to reconcile these data which include a light sterile neutrino in addition to the three standard ones .
implications for future experiments are commented . .
And you have already written the first three sentences of the full article: neutrinos are the only massless fermions predicted by the standard model ( sm ) .
this seems to be a reasonable assumption as none of the experiments designed to measure the neutrino mass in laboratory experiments have found any positive evidence for a non - zero neutrino mass . at present
the existing limits from laboratory searches are @xcite : @xmath0 the square of the electron neutrino mass is measured in tritium beta decay experiments by fitting the end point distribution . in several of these experiments there has been found a negative mass squared which is concluded to be due to unknown effects which cause the accumulation of events near the endpoint ..
Please generate the next two sentences of the article | this makes the limit above still far from certain .
the muon neutrino mass limit is derived from the measurement of the muon neutrino momenta on the decay @xmath1 , while the tau neutrino mass limit given above is based on kinematics of @xmath2 decays . for a detail discussion on the @xmath2 neutrino mass limit see @xcite . however , the confidence on the masslessness of the neutrino is now under question due to the important results of underground experiments , starting by the geochemical experiments of davis and collaborators till the more recent gallex , sage , kamiokande and superkamiokande experiments @xcite . |
3,527 | Suppose that you have an abstract for a scientific paper: let @xmath0}$ ] be the linear brownian motion and @xmath1}$ ] be the @xmath2-fold integral of brownian motion , @xmath3 being a positive integer : @xmath4$.}\ ] ] in this paper we construct several bridges between times @xmath5 and @xmath6 of the process @xmath1}$ ] involving conditions on the successive derivatives of @xmath7 at times @xmath5 and @xmath6 . for this family of bridges
, we make a correspondance with certain boundary value problems related to the one - dimensional polyharmonic operator .
we also study the classical problem of prediction .
our results involve various hermite interpolation polynomials . .
And you have already written the first three sentences of the full article: throughout the paper , we shall denote , for any enough differentiable function @xmath8 , its @xmath9-th derivative by @xmath10 or @xmath11 .
let @xmath0}$ ] be the linear brownian motion started at @xmath5 and @xmath12}$ ] be the linear brownian bridge within the time interval @xmath13 $ ] : @xmath12}=(b(t)|b(0)=b(1)=0)_{t\in [ 0,1]}$ ] .
these processes are gaussian processes with covariance functions @xmath14 for a given continuous function @xmath15 , the functions @xmath16 and @xmath17 respectively defined on @xmath13 $ ] by @xmath18 are the solutions of the respective boundary value problems on @xmath13 $ ] : @xmath19 observe that the differential equations are the same in both cases ..
Please generate the next two sentences of the article | only the boundary conditions differ .
they are dirichlet - type boundary conditions for brownian bridge while they are dirichlet / neumann - type boundary conditions for brownian motion . |
3,528 | Suppose that you have an abstract for a scientific paper: we examine the growth of entanglement under a quantum quench at point contacts of simple fractional quantum hall fluids and its relation with the measurement of local observables . recently
klich and levitov proposed that the noise generated from a local quantum quench provides a measure of the entanglement entropy .
their methods were specific to non - interacting electrons and the generalization to interacting systems was left as an open question . in this work ,
we generalize their result to the laughlin states .
we investigate the noise generated in the current along the edge of a fractional quantum hall state at filling factors @xmath0 , when a quantum point contact , initially closed , is fully opened at some initial time @xmath1 .
we find that local quenching in these systems gives time dependent correlation functions that have universal behavior on sufficiently long time and length scales .
we calculate the noise and full counting statistics for @xmath0 and find that in general , the entanglement entropy and noise generated are unrelated quantities .
we also discuss a generalization of this problem to the critical quantum ising spin chain . .
And you have already written the first three sentences of the full article: quantum impurity problems in 1 + 1 dimensions have long been the subject of intense study due to numerous applications in fields such as quantum wires , the quantum hall effect and the kondo problem . in particular ,
much research has been invested into understanding the behavior of particle transfer through an impurity and of growing interest experimentally and theoretically are the statistics of the fluctuations in the transferred charge .
most efforts have been concentrated on the shot noise which is sensitive to the quantization of charge and can give useful information about the system.@xcite in recent years , it was realized that the full counting statistics , probability distribution @xmath2 of the transmitted charge @xmath3 in a given time window @xmath4 , contains more information.@xcite along with the shot noise , the full counting statistics also contains information about the higher order correlations which are of interest experimentally ..
Please generate the next two sentences of the article | it has been suggested that the third moment may give a more reliable measure of the charge than the shot noise.@xcite recent experimental efforts suggest that the higher moments of the full counting statistics may be accessible.@xcite in cases where fermi liquid theory applies , the full counting statistics has been studied extensively ( see ref . [ ] for a review ) .
systems of strongly interacting electrons , though of importance in 1 + 1 dimensional quantum wires , the quantum hall effect and kondo problem have been less well studied . |
3,529 | Suppose that you have an abstract for a scientific paper: the sensitivity of imaging air cherenkov telescopes ( iacts ) worsens significantly at low energies because the @xmath0/hadron separation becomes much more complex . in this paper
we study the impact of the single electromagnetic subcascade events on the efficiency of the @xmath0/hadron separation for a system of four iacts using monte carlo simulations .
the studies are done for : two different altitudes of the observatory , three different telescope sizes and two hadron interaction models ( gheisha and fluka ) .
more than 90@xmath1 of the single electromagnetic proton - induced subcascade events are showers with primary energy below 200 gev , regardless on the trigger threshold .
the estimated efficiency of the @xmath0/hadron separation using the fluka model is similar to results obtained using the gheisha model .
nevertheless , for at least one triggered telescope only , a higher fraction of single electromagnetic subcascade events was obtained from the fluka model .
finally , the calculated quality factors are anti - correlated with the contributions of the false @xmath0-ray events in the proton initiated showers .
therefore , the occurrence of single electromagnetic subcascade events is one of the main reasons of the worsening of the primary @xmath0-ray selection efficiency at low energies . _
keywords _ : @xmath0-rays : general methods : observational instrumentation : detectors telescopes .
And you have already written the first three sentences of the full article: the discovery of the first tev @xmath0-ray source ( the crab nebula ) in 1989 by the whipple collaboration @xcite initiated a fast development of ground - based @xmath0-ray astronomy .
the imaging air cherenkov technique has been successfully used since the first source was discovered .
imaging air cherenkov telescope ( iact ) measure the cherenkov light from extensive air showers ( eas ) ..
Please generate the next two sentences of the article | the cherenkov photons that are reflected by the telescope mirror are recorded by a matrix of photomultipliers ( the so - called telescope camera ) mounted in the focal plane of iact .
the shower image that is formed in the camera is a two dimensional angular distribution of the cherenkov light . |
3,530 | Suppose that you have an abstract for a scientific paper: we show radio continuum images of several molecular complexes in the inner galaxy and report the presence of dark features that coincide with dense molecular clouds . unlike infrared dark clouds , these features which we call
`` radio dark clouds '' are produced by a deficiency in radio continuum emission from molecular clouds that are embedded in a bath of uv radiation field or synchrotron emitting cosmic ray particles .
the contribution of the continuum emission along different pathlengths results in dark features that trace embedded molecular clouds .
the new technique of identifying cold clouds can place constraints on the depth and the magnetic field of molecular clouds when compared to those of the surrounding hot plasma radiating at radio wavelengths .
the study of five molecular complexes in the inner galaxy , sgr a , sgr b2 , radio arc , the snake filament and g359.75 - 0.13 demonstrate an anti correlation between the distributions of radio continuum and molecular line and dust emission .
radio dark clouds are identified in gbt maps and vla images taken with uniform sampling of _ uv _ coverage .
the level at which the continuum flux is suppressed in these sources suggests that the depth of the molecular cloud is similar to the size of the continuum emission within a factor of two .
these examples suggest that high resolution , high dynamic range continuum images can be powerful probes of interacting molecular clouds with massive stars and supernova remnants in regions where the kinematic distance estimates are ambiguous as well as in the nuclei of active galaxies . & pdflatex # 1 ( g10 ^ 3 g_0 ) ^#1 # 1 10^#1 km s@xmath0 # 1 10^#1 # 1 # 2 ^#2
u#1 @xmath1 i v .
And you have already written the first three sentences of the full article: the inner few degrees of the galactic center show a large concentration of molecular , atomic hydrogen and dust clouds ( pierce - price et al . 2000 ; lang et al . 2010 ; molinari et al . 2011 ) .
the molecular gas toward the galactic center is considered to reside in the so - called central molecular zone ( cmz ) and consists of a mixture of diffuse and dense components ( morris and serabyn 1996 ; martin et al . 2004 ; sawada et al . 2004
; oka et al . 2005 ; yusef - zadeh et al ..
Please generate the next two sentences of the article | radio continuum emission from this region is also extended and is produced by a mixture of thermal and nonthermal processes ( nord et al .
2004 ; yusef - zadeh et al . 2004 ; law et al . |
3,531 | Suppose that you have an abstract for a scientific paper: we investigate a double - layer of penetrable ions near a charged wall . we find a new mechanism for charge reversal that occurs in the weak - coupling regime and , accordingly , the system is suitable for the mean - field analysis .
the penetrability is achieved by smearing - out the ionic charge inside a sphere , so there is no need to introduce non - electrostatic forces and the system in the low coupling limit can be described by a modified version of the poisson - boltzmann equation .
the predictions of the theory are compared with the monte carlo simulations . .
And you have already written the first three sentences of the full article: overcharging is a surprising phenomenon in which conterions adsorbed to a surface exceed the number of fixed surface charges @xcite . as a consequence
, coions are drawn from the bulk toward the overcharged surface leading to a formation of a `` triple - layer '' .
because the underlying mechanism of overcharging relies on electrostatic correlations @xcite , it has become synonymous with the strong - coupling limit ..
Please generate the next two sentences of the article | indeed , a mean - field treatment which accurately captures the weak - coupling limit , can not describe overcharging .
( however , the mean - field in combination with the excluded volume interactions can induce overcharging if the bulk volume fraction of an electrolyte is sufficiently large to generate a depletion force that pushes particles against a surface . |
3,532 | Suppose that you have an abstract for a scientific paper: the thickness dependence of the superconducting energy gap @xmath0 of double hexagonally close packed ( dhcp ) lanthanum islands grown on w(110 ) is studied by scanning tunneling spectroscopy , from the bulk to the thin film limit .
superconductivity is suppressed by the boundary conditions for the superconducting wavefunction at the surface and w / la interface , leading to a linear decrease of the critical temperature @xmath1 as a function of the inverse film thickness . for thick , bulk - like films ,
@xmath0 and @xmath1 are 40% larger as compared to literature values of dhcp la measured by other techniques .
this finding is reconciled by examining the effects of surface contamination as probed by modifications of the surface state , suggesting that the large @xmath1 originates in the superior purity of the samples investigated here .
_ keywords _ : lanthanum , superconductivity , scanning tunneling spectroscopy .
And you have already written the first three sentences of the full article: commonly , the energy gap @xmath2 of a superconducting film is determined in tunneling experiments where a conducting electrode and the superconductor are separated by an insulating layer . in early tunneling experiments ,
planar tunneling junctions with a thick oxide layer @xcite or point contacts @xcite were utilized to determine the superconducting properties of many typical superconductors . with the advancement of low temperature scanning tunneling spectroscopy ( sts ) in ultra - high vacuum ( uhv ) , it has become possible to probe _ in - situ _ fabricated superconductors , and to determine @xmath2 with atomic - scale spatial resolution @xcite . here
, @xmath2 can be determined with a high degree of accuracy as a result of higher sample quality resulting from _ in - situ _ preparation , and utilizing the vacuum barrier which acts as a perfect insulator . in recent years.
Please generate the next two sentences of the article | , such investigations have shown that seemingly well understood , elemental bcs superconductors , like pb or in , behave dramatically different at the thin film limit . for example , the onset of quantum well states allows superconductivity to remain robust in the thin film limit @xcite , or even persist down to a single layer @xcite . for other systems , like pb - bi alloys
, it has been shown that @xmath1 can be engineered by modifying the fermi wavevector @xmath3 @xcite . |
3,533 | Suppose that you have an abstract for a scientific paper: in this note we show that conforming galerkin approximations for @xmath0-harmonic functions tend to @xmath1-harmonic functions in the limit @xmath2 and @xmath3 , where @xmath4 denotes the galerkin discretisation parameter . .
And you have already written the first three sentences of the full article: let @xmath5 be an open and bounded set . for a given function @xmath6
we denote the gradient of @xmath7 as @xmath8 and its hessian @xmath9 .
the @xmath1-laplacian is the partial differential equation ( pde ) @xmath10 where `` @xmath11 '' is the tensor product between @xmath12-vectors and `` @xmath13 '' the frobenius inner product between matrices ..
Please generate the next two sentences of the article | this problem is the prototypical example of a pde from calculus of variations in @xmath14 , arising as the analogue of the _ euler lagrange _ equation of the functional @xmath15 : = \norm{\d u}_{{\ensuremath{\ll^{\infty}}}(\w)}\ ] ] @xcite and as the ( weighted ) formal limit of the variational @xmath0-laplacian @xmath16 the @xmath0-laplacian is a divergence form problem and appropriate _
weak _ solutions to this problem are defined in terms of duality , or integration by parts . in passing to the limit ( @xmath17 ) the problem loses its divergence structure . in the nondivergence |
3,534 | Suppose that you have an abstract for a scientific paper: we have calculated the emergent x ray properties for models of cluster cooling flows including the effects of accumulated cooled material .
the opacity of this cooled gas can reduce the overall x ray luminosity of the cooling flow , and values of @xmath0 based on these luminosities can underestimate the true value by factors of @xmath1 .
we find that accumulated cooled material can produce emergent surface brightness profiles much like those observed even for nearly homogeneous gas distributions .
consequently , much more of the gas may be cooling below x ray emitting temperatures in the central regions of cooling flows ( @xmath2 kpc ) than one would infer from observed x ray surface brightness profiles assuming the gas was optically thin .
similarly , the central densities and pressures in cooling flows may have been underestimated .
we show that distributed absorption in cooling flows produces a number of observable effects in the spectrum which may allow it to be differentiated from absorption due to gas in our galaxy .
these include a characteristic suppression of the continuum below @xmath1 kev , absorption features such as a redshifted o k edge , and diminished intensity of resonance emission lines .
spectra including the effects of intrinsic absorption are not well fit by foreground absorbing models .
attempting to fit such models to the spatially resolved spectra can lead to underestimates of the true absorbing column by factors of 320 .
fits to integrated spectra of the entire cooling flow region can either underestimate or overestimate the mass of the absorbing gas depending on the specifics of the model .
we discuss the potential detection of these effects with _
axaf _ , _ xmm _ , and astro - e . .
And you have already written the first three sentences of the full article: more than half of the clusters of galaxies observed at x ray wavelengths exhibit evidence for cool gas in their cores ( edge , stewart , & fabian 1992 ) .
the cooling time of this gas is often short compared to cluster ages ; therefore , the gas cools at rates that are often very large , @xmath3 yr@xmath4 . in the absence of a heating mechanism to balance cooling , gravity and pressure from the hotter ,
surrounding gas will drive the cooling material into the core of the cluster ..
Please generate the next two sentences of the article | if cooling flows are long lived phenomena , these rates imply that @xmath5@xmath6 of material would cool over the lifetime of the cluster .
determining the final state of this cooling material remains the fundamental problem concerning the cooling flow theory . |
3,535 | Suppose that you have an abstract for a scientific paper: let @xmath0 be the @xmath1-dimensional unit torus , @xmath2 .
the torsional rigidity of an open set @xmath3 is the integral with respect to lebesgue measure over all starting points @xmath4 of the expected lifetime in @xmath5 of a brownian motion starting at @xmath6 . in this paper
we consider @xmath7 $ ] , the complement of the path @xmath8 $ ] of an independent brownian motion up to time @xmath9 .
we compute the leading order asymptotic behaviour of the expectation of the torsional rigidity in the limit as @xmath10 . for @xmath11
the main contribution comes from the components in @xmath12 $ ] whose inradius is comparable to the largest inradius , while for @xmath13 most of @xmath14 $ ] contributes .
a similar result holds for @xmath15 after the brownian path is replaced by a shrinking wiener sausage @xmath16 $ ] of radius @xmath17 , provided the shrinking is slow enough to ensure that the torsional rigidity tends to zero .
asymptotic properties of the capacity of @xmath8 $ ] in @xmath18 and @xmath19 $ ] in @xmath20 , @xmath15 , play a central role throughout the paper .
our results contribute to a better understanding of the geometry of the complement of brownian motion on @xmath0 , which has received a lot of attention in the literature in past years .
0.5truecm _ ams _ 2000 _ subject classifications .
_ 35j20 , 60g50 .
+ _ key words and phrases . _
torus , laplacian , brownian motion , torsional rigidity , inradius , capacity , spectrum , heat kernel . _ acknowledgment . _
the authors acknowledge support by the leverhulme trust through international network grant _ laplacians , random walks , bose gas , quantum spin systems_. eb is supported by snsf - grant 20 - 100536/1 .
fdh is supported by erc advanced grant 267356-varis and nwo gravitation grant 024.002.003-networks .
the authors thank greg lawler for helpful discussions about capacity of the wiener sausage . .
And you have already written the first three sentences of the full article: section [ background ] provides our motivation for looking at torsional rigidity , and points to the relevant literature .
section [ torsrig ] introduces our main object of interest , the torsional rigidity of the complement of brownian motion on the unit torus .
section [ asympscal ] states our main theorems ..
Please generate the next two sentences of the article | section [ disc ] places these theorems in their proper context and makes a link with the principal dirichlet eigenvalue of the complement .
section [ sketch ] gives a brief sketch of the main ingredients of the proofs and provides an outline of the rest of the paper . |
3,536 | Suppose that you have an abstract for a scientific paper: we study the interplay between nel - antiferromagnetism and the paramagnetic metal - insulator - transition ( pmit ) on a bethe lattice with nearest and next - nearest neighbor hopping @xmath0 and @xmath1 .
we concentrate in this paper on the situation at half - filling . for @xmath2
the pmit outgrows the antiferromagnetic phase and shows a scenario similar to v@xmath3o@xmath4 . in this parameter regime
we also observe a novel magnetic phase . .
And you have already written the first three sentences of the full article: understanding correlation effects is one major goal of condensed matter physics .
strong correlations manifest themselves in various forms . the paramagnetic mott - hubbard metal - insulator - transition ( pmit)@xcite is a well - known and interesting example . with increasing interaction strength the fermi liquid state breaks down at a critical value and an insulator
is formed ..
Please generate the next two sentences of the article | another fundamental example is magnetism , where electrons reduce the energetic cost of the coulomb - interaction by ordering .
both effects can of course occur simultaneously and are the heart of the extremely rich phase diagram of e.g. transition metal compounds like for example v@xmath3o@xmath4 or latio@xmath4@xcite . besides strong correlations , another major ingredient for the understanding of the phase diagram of compounds like v@xmath3o@xmath4 is frustration . |
3,537 | Suppose that you have an abstract for a scientific paper: this paper investigates grb 050802 , one of the best examples of a _ swift _ gamma - ray burst afterglow that shows a break in the x - ray lightcurve , while the optical counterpart decays as a single power - law .
this burst has an optically bright afterglow of 16.5 magnitude , detected throughout the 170 - 650 nm spectral range of the uvot on - board _
swift_. observations began with the xrt and uvot telescopes @xmath0 after the initial trigger and continued for @xmath1 .
the x - ray lightcurve consists of three power - law segments : a rise until 420s , followed by a slow decay with @[email protected] until 5000s , after which , the lightcurve decays faster with a slope of @[email protected] .
the optical lightcurve decays as a single power - law with @[email protected] throughout the observation .
the x - ray data on their own are consistent with the break at 5000s being due to the end of energy injection . modelling the optical to x - ray spectral energy distribution , we find that the optical afterglow can not be produced by the same component as the x - ray emission at late times , ruling out a single component afterglow .
we therefore considered two - component jet models and find that the x - ray and optical emission is best reproduced by a model in which both components are energy injected for the duration of the observed afterglow and the x - ray break at 5000s is due to a jet break in the narrow component .
this bright , well - observed burst is likely a guide for interpreting the surprising finding of _ swift _ that bursts seldom display achromatic jet breaks .
[ firstpage ] gamma - rays : bursts .
And you have already written the first three sentences of the full article: gamma ray bursts ( grbs ) are the most energetic explosions that take place in our universe , with a typical energy of @xmath6 released on a timescale of between a millisecond and a few thousand seconds .
the release of such a considerable amount of energy over such a short period requires an outflow that is relativistic @xcite and is likely to be anisotropic @xcite .
the energy within the outflow is released primarily though shocks ..
Please generate the next two sentences of the article | the grb is thought to be produced through internal shocks from interactions between successive shells of ejecta @xcite .
subsequently an afterglow is emitted as the outflow is decelerated through collisionless shocks with the external medium @xcite . |
3,538 | Suppose that you have an abstract for a scientific paper: we develop a theory for the market impact of large trading orders , which we call _ metaorders _ because they are typically split into small pieces and executed incrementally .
market impact is empirically observed to be a concave function of metaorder size , i.e. the impact per share of large metaorders is smaller than that of small metaorders .
we formulate a stylized model of an algorithmic execution service and derive a fair pricing condition , which says that the average transaction price of the metaorder is equal to the price after trading is completed .
we show that at equilibrium the distribution of trading volume adjusts to reflect information , and dictates the shape of the impact function .
the resulting theory makes empirically testable predictions for the functional form of both the temporary and permanent components of market impact .
based on the commonly observed asymptotic distribution for the volume of large trades , it says that market impact should increase asymptotically roughly as the square root of size , with average permanent impact relaxing to about two thirds of peak impact . .
And you have already written the first three sentences of the full article: market impact is the expected price change conditioned on initiating a trade of a given size and a given sign .
understanding market impact is important for several reasons .
one motivation is practical : to know whether a trade will be profitable it is essential to be able to estimate transaction costs , and in order to optimize a trading strategy to minimize such costs , it is necessary to understand the functional form of market impact ..
Please generate the next two sentences of the article | another motivation is ecological : impact exerts selection pressure against a fund becoming too large , and therefore is potentially important in determining the size distribution of funds . finally , an important motivation is theoretical : market impact reflects the shape of excess demand , the understanding of which has been a central problem in economics since the time of alfred marshall . in this paper
we present a theory for the market impact of large trading orders that are split into pieces and executed incrementally . |
3,539 | Suppose that you have an abstract for a scientific paper: the free energy and local height probabilities of the dilute a models with broken @xmath0 symmetry are calculated analytically using inversion and corner transfer matrix methods .
these models possess four critical branches .
the first two branches provide new realisations of the unitary minimal series and the other two branches give a direct product of this series with an ising model .
we identify the integrable perturbations which move the dilute a models away from the critical limit .
generalised order parameters are defined and their critical exponents extracted .
the associated conformal weights are found to occur on the diagonal of the relevant kac table . in an appropriate regime
the dilute a@xmath1 model lies in the universality class of the ising model in a magnetic field . in this case
we obtain the magnetic exponent @xmath2 directly , without the use of scaling relations .
3.6 mm 3.6 mm # 1 .
And you have already written the first three sentences of the full article: # 1#2 # 1#2#3#4#5 w # 1 ( cc#5 & # 4 + # 2 & # 3 ) # 1#2#3#4#5 # 1 ( cc#5 & # 4 + # 2 & # 3 ) # 1#2#3 # 1#2#3 in the last decade many infinite hierarchies of exactly solvable models have been found . of foremost importance among these models
are the restricted solid - on - solid ( rsos ) models of andrews , baxter and forrester ( abf ) @xcite . in these models
each site of the lattice carries a height variable , restricted to the values @xmath3 with @xmath4 , subject to the rule that heights on neighbouring lattice sites differ by @xmath5 ..
Please generate the next two sentences of the article | if the allowed heights are represented by the nodes in the following diagram , @xmath6 the adjacency rule requires that neighbouring lattice sites take values that are adjacent on the diagram .
andrews , baxter and forrester considered four different regimes , labelled i iv . |
3,540 | Suppose that you have an abstract for a scientific paper: large - scale qrpa calculations of the e1 strength are performed on top of hfb calculations in order to derive the radiative neutron capture cross sections for the whole nuclear chart .
the spreading width of the gdr is taken into account by analogy with the second - rpa ( srpa ) method . the accuracy of hfb+qrpa model based on various skyrme forces with different pairing prescription and parameterization is analyzed .
it is shown that the present model allows to constrain the effective nucleon - nucleon interaction with the gdr data and to provide quantitative predictions of dipole strengths .
16.2 cm -.54 cm -.54 cm nuclear reactions : qrpa , e1-strength , nuclear forces .
And you have already written the first three sentences of the full article: about half of the nuclei with @xmath0 observed in nature are formed by the so - called rapid neutron - capture process ( or r - process ) of nucleosynthesis , occurring in explosive stellar events .
the r - process is believed to take place in environments characterized by high neutron densities ( @xmath1 ) , so that successive neutron captures proceed into neutron - rich regions well off the @xmath2-stability valley forming exotic nuclei that can not be produced and therefore studied in the laboratory .
if the temperatures or the neutron densities characterizing the r - process are low enough to break the @xmath3 equilibrium , the r - abundance distribution depends directly on the neutron capture rates by the so - produced exotic neutron - rich nuclei @xcite ..
Please generate the next two sentences of the article | the neutron capture rates are commonly evaluated within the framework of the statistical model of hauser - feshbach ( although the direct capture contribution can play an important role for such exotic nuclei ) .
this model makes the fundamental assumption that the capture process takes place with the intermediary formation of a compound nucleus in thermodynamic equilibrium . in this approach , |
3,541 | Suppose that you have an abstract for a scientific paper: the vietoris - rips filtration for an @xmath0-point metric space is a sequence of large simplicial complexes adding a topological structure to the otherwise disconnected space .
the persistent homology is a key tool in topological data analysis and studies topological features of data that persist over many scales .
the fastest algorithm for computing persistent homology of a filtration has time @xmath1 , where @xmath2 is the number of updates ( additions or deletions of simplices ) , @xmath3 is the time for multiplication of @xmath4 matrices . for a space of @xmath0 points given by their pairwise distances , we approximate the vietoris - rips filtration by a zigzag filtration consisting of @xmath5 updates , which is sublinear in @xmath0 .
the constant depends on a given error of approximation and on the doubling dimension of the metric space .
then the persistent homology of this sublinear - size filtration can be computed in time @xmath6 , which is subquadratic in @xmath0 . .
And you have already written the first three sentences of the full article: the aim of topological data analysis is to understand the shape of unstructured data often given as finitely many points in a metric space .
usually , the shape of such a point cloud is studied through a filtration of complexes built on given points .
for instance , the vietoris - rips complex contains edges , triangles , tetrahedra spanned by points whose pairwise distances are less than a certain scale ..
Please generate the next two sentences of the article | the persistent homology of the resulting filtration over all scales captures topological features that persist over a long time interval .
if given points are densely sampled from a compact set in @xmath7 , the vietoris - rips complex at a certain scale correctly represents the topology of the set @xcite . for |
3,542 | Suppose that you have an abstract for a scientific paper: for a group @xmath0 , the notion of a ribbon @xmath0-category was introduced in @xcite with a view towards constructing @xmath1-dimensional homotopy quantum field theories ( hqft s ) with target @xmath2 .
we discuss here how to derive ribbon @xmath0-categories from a simple complex lie algebra @xmath3 where @xmath0 is the center of @xmath3 .
our construction is based on a study of representations of the quantum group @xmath4 at a root of unity @xmath5 . under certain assumptions on @xmath5 ,
the resulting @xmath0-categories give rise to numerical invariants of pairs ( a closed oriented 3-manifold @xmath6 , an element of @xmath7 ) and to 3-dimensional hqft s .
-0.2 cm -0.2 cm [ section ] [ thm]lemma [ thm]proposition [ thm]corollary [ thm]remark [ section ] [ section ] c i d zz rr = 12.5 cm = 19.0 cm = 0.5 cm = 0pt = 12pt = 12pt hom i d sgn .
And you have already written the first three sentences of the full article: in order to construct @xmath1-dimensional homotopy quantum field theories ( hqft s ) , the second author introduced for a group @xmath0 the notions of a ribbon @xmath0-category and a modular ( ribbon ) @xmath0-category . the aim of this paper is to analyze the categories of representations of quantum groups ( at roots of unity ) from this prospective .
the role of @xmath0 will be played by the center of the corresponding lie algebra .
we begin with a general theory of ribbon @xmath0-categories with abelian @xmath0 ..
Please generate the next two sentences of the article | according to @xcite , any modular ( ribbon ) @xmath0-category @xmath8 gives rise to a 3-dimensional hqft with target @xmath2 .
such an hqft comprises several ingredients including a homotopy modular functor " assigning modules to pairs ( a surface @xmath9 , an element of @xmath10 ) and a numerical invariant of pairs ( a closed oriented 3-manifold @xmath6 , a cohomology class @xmath11 ) . |
3,543 | Suppose that you have an abstract for a scientific paper: we use a generalized gross - pitaevskii equation for the condensate and a semi - classical kinetic equation for the noncondensate atoms to discuss the scissors mode in a trapped bose - condensed gas at finite temperatures .
both equations include the effect of @xmath0 collisions between the condensate and noncondensate atoms .
we solve the coupled moment equations describing oscillations of the quadrupole moments of the condensate and noncondensate components to find the collective mode frequencies and collisional damping rates as a function of temperature .
our calculations extend those of gury - odelin and stringari at @xmath1 and in the normal phase .
they complement the numerical results of jackson and zaremba , although landau damping is left out of our approach .
our results are also used to calculate the quadrupole response function , which is related to the moment of inertia .
it is shown explicitly that the moment of inertia of a trapped bose gas at finite temperatures involves a sum of an irrotational component from the condensate and a rotational component from the thermal cloud atoms . .
And you have already written the first three sentences of the full article: superfluidity resulting from a bose - einstein condensate ( bec ) in atomic gases is characterized by the irrotational nature of the condensate flow .
the recent experimental observation of the scissors mode in a trapped bose - condensed gas @xcite clearly demonstrated the irrotational nature of a trapped superfluid bose gas .
the scissors mode is the oscillation of the atomic cloud with respect to a symmetry axis of an anisotropic trap potential @xcite , induced by a sudden rotation of the trap about this axis . above the bose - einstein transition temperature ( @xmath2 ) ,.
Please generate the next two sentences of the article | the thermal cloud exhibits two normal mode frequencies corresponding to the rotational and irrotational motion .
in contrast , the pure condensate motion at @xmath1 only exhibits one frequency , since only irrotational motion is allowed . the above distinction between the condensate ( superfluid ) oscillation at @xmath3 and the thermal gas ( normal fluid ) oscillation above @xmath2 |
3,544 | Suppose that you have an abstract for a scientific paper: we study theoretically the ultrafast nonlinear optical response of quantum well excitons in a perpendicular magnetic field .
we address the role of many - body correlations originating from the electron scattering between landau levels ( ll ) . in the linear optical response , the processes involving inter - ll transitions are suppressed provided that the magnetic field is sufficiently strong .
however , in the _ nonlinear _ response , the auger processes involving inter - ll scattering of _ two _ photoexcited electrons remain unsuppressed .
we show that auger scattering plays the dominant role in the coherent exciton dynamics in strong magnetic field .
we perform numerical calculations for the third - order four - wave - mixing ( fwm ) polarization which incorporate the auger processes nonperturbatively . we find that inter - ll scattering leads to a strong enhancement and to oscillations of the fwm signal at negative time delays .
these oscillations represent quantum beats between optically - inactive two - exciton states related to each other via auger processes . .
And you have already written the first three sentences of the full article: it has been established that many - body processes play an important role in the _ transient _ optical response of semiconductors in the coherent regime@xcite .
the coulomb correlations between photoexcited carriers are especially strong in the presence of magnetic field . by suppressing kinetic energy of electrons and holes in two spatial dimensions ( magnetic confinement ) ,
a high magnetic field enhances the relative strength of interactions between them@xcite . in bulk semiconductors , a dominant role of coulomb correlations in magnetic field.
Please generate the next two sentences of the article | was demonstrated in four - wave mixing ( fwm ) spectroscopy experiments@xcite .
for example , a huge ( several orders of magnitude ) enhancement of the fwm signal was observed as the field exceeded certain characteristic value . a crossover to |
3,545 | Suppose that you have an abstract for a scientific paper: we consider a lattice model for amphiphiles in a solvent with molecules chemically similar to one part of the amphiphilic molecule .
the dependence of the interaction potential on orientation of the amphiphilic molecules is taken into account explicitly .
the model is solved exactly in one dimension by the transfer - matrix method . in particular , pressure as a function of concentration ,
correlation function and specific heat are calculated .
the model is compared with the recently introduced lattice model for colloidal self - assembly , where the particles interact with the isotropic short - range attraction and long - range repulsion ( salr ) potential .
similarities between the amphiphilic and the colloidal self - assembly are highlighted . .
And you have already written the first three sentences of the full article: statistical thermodynamics of simple liquids and their mixtures has been extensively studied , and thermodynamical and structural properties of such systems are well understood @xcite . in particular ,
an accurate equation of state of the lennard - jones fluid has been obtained @xcite .
the impressive development of the theory was possible thanks to the key contributors including prof ..
Please generate the next two sentences of the article | tomas boublik and prof .
ivo nezbeda . |
3,546 | Suppose that you have an abstract for a scientific paper: we examine the relationship between the _ algebraic @xmath0-calculus _ , a fragment of the differential @xmath0-calculus and the _ linear - algebraic @xmath0-calculus _ , a candidate @xmath0-calculus for quantum computation .
both calculi are algebraic : each one is equipped with an additive and a scalar - multiplicative structure , and their set of terms is closed under linear combinations .
however , the two languages were built using different approaches : the former is a call - by - name language whereas the latter is call - by - value ; the former considers algebraic equalities whereas the latter approaches them through rewrite rules . in this paper , we analyse how these different approaches relate one to the other . to this end , we propose four canonical languages based on each of the possible choices : call - by - name versus call - by - value , algebraic equality versus algebraic rewriting .
we show that the various languages simulate one another . due to subtle interaction between beta - reduction and algebraic rewriting , to make the languages consistent some additional hypotheses such as confluence might be required .
we carefully devise the required properties for each proof , making them general enough to be valid for any sub - language satisfying the corresponding properties . .
And you have already written the first three sentences of the full article: [ [ algebraic - lambda - calculi . ] ] algebraic @xmath0-calculi .
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + two algebraic versions of the @xmath0-calculus arise independently in distinct contexts : the algebraic @xmath0-calculus ( @xmath1 ) @xcite and the linear algebraic @xmath0-calculus ( @xmath2 ) @xcite .
the former has been introduced in the context of linear logic as a fragment of the differential @xmath0-calculus @xcite : the algebraic structure allows to gather in a non deterministic manner different terms , _.
Please generate the next two sentences of the article | i.e. _ each term represents one possible execution .
the latter has been introduced as a candidate @xmath0-calculus for quantum computation : in @xmath2 , a linear combination of terms reflects the phenomenon of superposition , _ |
3,547 | Suppose that you have an abstract for a scientific paper: we evaluate the microwave admittance of a one - dimensional chain of fluxonium qubits coupled by shared inductors . despite its simplicity
, this system exhibits a rich phase diagram .
a critical applied magnetic flux separates a homogeneous ground state from a phase with a ground state exhibiting inhomogeneous persistent currents . depending on the parameters of the array
, the phase transition may be a conventional continuous one , or of a commensurate - incommensurate nature .
furthermore , quantum fluctuations affect the transition and possibly lead to the presence of gapless `` floating phases '' .
the signatures of the soft modes accompanying the transitions appear as a characteristic frequency dependence of the dissipative part of admittance . .
And you have already written the first three sentences of the full article: vortices of persistent current in superconductors have been viewed for a long time as a testing ground for various models of classical and quantum phase transitions .
this is due to relatively strong interactions between vortices coupled with a high degree of control over the vortex arrays .
for example , inter - vortex interactions in the presence of a periodic external potential ( created experimentally by modulation of the superconducting film thickness @xcite ) made vortices a convenient target for investigation of commensurability transitions.@xcite theoretical studies of the effects of randomness on vortex structure and vortex dynamics have led to the notion of collective pinning,@xcite with importance stretching well beyond the physics of superconductivity.@xcite later , the discovery of high - temperature superconductors triggered studies of the vortex lattice melting transition and glassy behavior@xcite in layered superconductors as well as structural transitions of vortices interacting with columnar defects.@xcite because vortices in continuous superconductors have normal cores , vortex motion is dissipative@xcite and much of the above - mentioned work used classical statistical mechanics to address collective phenomena in vortex arrays.@xcite the effects of quantum fluctuations of vortices in continuous films become important only close to the supeconductor - insulator transition , which requires special tuning of the films normal - state resistance.@xcite in arrays of josephson junctions , however , vortices do not have cores , allowing for the study of quantum fluctuations ..
Please generate the next two sentences of the article | an array of small superconducting islands connected by josephson junctions , where the island charging energies were sufficiently large for quantum effects to be important,@xcite was used in attempts to observe a quantum kosterlitz - thouless ( kt ) transition @xcite and mott transition@xcite in a 1d array .
while these works advanced the nanofabrication techniques needed to produce highly regular arrays of small josephson junctions , the measurement results were ambiguous . |
3,548 | Suppose that you have an abstract for a scientific paper: we study the moduli of trigonal curves .
we establish the exact upper bound of @xmath0 for the slope of trigonal fibrations . here , the slope of any fibration @xmath1 of stable curves with smooth general member is the ratio @xmath2 of the restrictions of the boundary class @xmath3 and the hodge class @xmath4 on the moduli space @xmath5 to the base @xmath6 .
we associate to a trigonal family @xmath7 a canonical rank two vector bundle @xmath8 , and show that for bogomolov - semistable @xmath8 the slope satisfies the stronger inequality @xmath9 .
we further describe the rational picard group of the trigonal locus @xmath10 in the moduli space @xmath5 of genus @xmath11 curves . in the even genus case ,
we interpret the above bogomolov semistability condition in terms of the so - called maroni divisor in @xmath10 . .
And you have already written the first three sentences of the full article: [ introduction ] in this paper @xmath12 denotes the deligne - mumford compactification of the moduli space of smooth curves over @xmath13 of genus @xmath14 .
the boundary locus @xmath15 of @xmath12 consists of nodal curves with finite automorphism groups , which together with the smooth curves are referred to as _
stable _ curves . the locus of hyperelliptic curves will be denoted by @xmath16 , and the closure of the locus of trigonal curves will be denoted by @xmath17.
Please generate the next two sentences of the article | . the main objects of our study will be families of genus @xmath11 stable curves , whose general members are smooth .
associated to any such _ flat and proper _ |
3,549 | Suppose that you have an abstract for a scientific paper: precision measurements of nature s fundamental couplings and a first measurement of the cosmological redshift drift are two of the key targets for future high - resolution ultra - stable spectrographs such as codex .
being able to do both gives codex a unique advantage , allowing it to probe dynamical dark energy models ( by measuring the behavior of their equation of state ) deep in the matter era and thereby testing classes of models that would otherwise be difficult to distinguish from the standard @xmath0cdm paradigm .
we illustrate this point with two simple case studies . .
And you have already written the first three sentences of the full article: the observational evidence for the acceleration of the universe demonstrates that canonical theories of gravitation and particle physics are incomplete , if not incorrect
. the next generation of astronomical facilities must therefore be able to carry out precision consistency tests of the standard cosmological model and search for definitive evidence of new physics beyond it .
codex @xcite is a spectrograph planned for the european extremely large telescope ( e - elt ) ..
Please generate the next two sentences of the article | it should provide the first measurement of the cosmological redshift drift ( known as the sandage - loeb test @xcite ) ; a detailed feasibility study has been carried out by liske _
@xcite , and other aspects relevant for our work have been explored in @xcite . |
3,550 | Suppose that you have an abstract for a scientific paper: we study the emission of scalar fields into the bulk from a six - dimensional rotating black hole pierced by a 3-brane .
we determine the angular eigenvalues in the presence of finite brane tension by using the continued fraction method .
the radial equation is integrated numerically , giving the absorption probability ( graybody factor ) in a wider frequency range than in the preexisting literature .
we then compute the power and angular momentum emission spectra for different values of the rotation parameter and brane tension , and compare their relative behavior in detail . as is expected from the earlier result for a nonrotating black hole
, the finite brane tension suppresses the emission rates .
as the rotation parameter increases , the power spectra are reduced at low frequencies due to the smaller hawking temperature and are enhanced at high frequencies due to superradiance .
the angular momentum spectra are enhanced over the whole frequency range as the rotation parameter increases .
the spectra and the amounts of energy and angular momentum radiated away into the bulk are thus determined by the interplay of these effects . .
And you have already written the first three sentences of the full article: braneworld models with large extra dimensions @xcite bring us an interesting possibility to address the hierarchy problem by lowering the fundamental scale of gravity down to order of tev .
it has been argued in the context of tev scale gravity that mini black holes might be created through high - energy particle collision at future colliders @xcite .
much effort has been directed towards a theoretical understanding of the black hole formation at tev energies ( e.g. , @xcite ) ..
Please generate the next two sentences of the article | after their production , the black holes will decay via hawking radiation @xcite .
this process provides a window to probe high - energy physics , gravity at small distances , and properties of extra dimensions , which motivates recent extensive studies on this topic . |
3,551 | Suppose that you have an abstract for a scientific paper: in this paper , we present a systematic study of beam shifts and angular momenta of paraxial vortex beams at air - left - handed material ( lhm ) interfaces .
it is shown that , compared to their counterparts at air - right - handed material ( rhm ) interfaces , the spatial goos - hnchen ( gh ) and imbert - fedorov ( if ) shifts remains the same , while the angular gh and if shifts are reversed , at air - lhm interfaces .
the spatial and angular shifts of paraxial vortex beams have their respective origins in transverse angular momenta and transverse linear momenta .
the spatial gh and if shifts remain unreversed as a result of the both reversions of transverse angular momenta and z - component linear momentum , while the angular gh and if shifts are reversed due to that the z - component linear momentum is reversed and the transverse linear momenta are unreversed , at air - lhm interfaces .
in addition , we perform a quantitative analysis on spin - orbit angular momentum conversion and orbit - orbit angular momentum conversion , which further helps us understand the essence of vortex beam shifts at air - lhm interfaces and their fundamental distinctions with those at air - rhm interfaces . .
And you have already written the first three sentences of the full article: [ introduction ] the reflection and transmission of light at air - medium interface has been a topic of ongoing investigation and contention .
initially , the amplitudes and directions of reflected and transmitted light were determined by fresnel formulas and snell s law .
deviations were later found in total internal reflection ( tir ) , however ..
Please generate the next two sentences of the article | they are goos - hnchen ( gh ) shift @xcite and imbert - fedorov ( if ) shift @xcite , which are parallel and perpendicular to the incident plane , respectively .
artmann formula @xcite for gh shift and schilling formula @xcite for if shift in tir are widely accepted . the exact formulas for if shifts in partial reflection and transmission , however , have divided many physicists @xcite . |
3,552 | Suppose that you have an abstract for a scientific paper: various superconductors , including cuprate superconductors , exhibit peculiar features above the transition temperature @xmath0 . in particular the observation of a large diamagnetism and nernst signal @xmath1 in a wide temperature window above @xmath0 attracted considerable attention . noting that this temperature window exceeds the fluctuation dominated regime drastically and that in these materials the spatial extent of homogeneity is limited , we explore the relevance of the zero dimensional ( 0d)-model , neglecting thermal fluctuations .
it is shown that both , the full 0d - model as well as its gaussian approximation , mimic the essential features of the isothermal magnetization curves @xmath2 in pb nanoparticles and various cuprates remarkably well .
this analysis also provides estimates for the spatial extent of the homogeneous domains giving rise to a smeared transition in zero magnetic field .
the resulting estimates for the amplitude of the in - plane correlation length exhibit a doping dependence reflecting the flow to the quantum phase transition in the underdoped limit .
furthermore it is shown that the isothermal nernst signal of a superconducting nb@xmath3si@xmath4 film , treated as @xmath5 , is fully consistent with this scenario .
accordingly , the observed diamagnetism above @xmath6 in pb nanoparticles , in the cuprates la@xmath7sr@xmath8cuo@xmath9 and bisr@xmath10ca@xmath10cuo@xmath11 , as well as the nernst signal in nb@xmath3si@xmath4 films , are all in excellent agreement with the scaling properties emerging from the 0d - model , giving a universal perspective on the interplay between diamagnetism , nernst signal , correlation length , and the limited spatial extent of homogeneity .
our analysis also provides evidence that singlet cooper pairs subjected to orbital pair breaking in a 0d system are the main source of the observed diamagnetism and nernst signal in an extended temperature window above @xmath0 . .
And you have already written the first three sentences of the full article: the detection of cooper pairs above the superconducting transition temperature @xmath0 has a long history , dating back to 1969.tinkham it implies that the average of the order parameter squared , @xmath12 , does not vanish above @xmath0 , either due to thermal fluctuations or the limited effective spatial extent of the system .
while the regime where thermal fluctuations dominate is reasonably well understood in terms of the scaling theory of critical phenomena subjected to finite size effects , ffh , tsh , kosh , hofer , book , parks , tsjs , larkin novel features have been observed considerably outside the fluctuation dominated regime .
recently , li _ et al_.@xcite have compiled the results of an extended experimental study of the isothermal magnetization of several families of cuprate superconductors over a rather broad range of temperatures and magnetic fields . from these.
Please generate the next two sentences of the article | , they infer that above the transition temperature @xmath0 , the isothermal diamagnetic contribution to the magnetization @xmath13 decreases initially with increasing magnetic field @xmath14 , applied parallel to the @xmath15-axis , consistent with @xmath16 , where @xmath17 is the diamagnetic susceptibility .
however , as @xmath14 increases @xmath13 tends to a minimum at @xmath18 and in excess of this characteristic field the magnetization increases and appears to approach zero , as shown in fig . |
3,553 | Suppose that you have an abstract for a scientific paper: wavelet sets that are finite unions of convex sets are constructed in @xmath0 , @xmath1 , for dilation by any expansive matrix that has a power equal to a scalar times the identity and also has all singular values greater than @xmath2 . in particular , we produce simple wavelet sets in every dimension for dilation by any real scalar greater than 1 . .
And you have already written the first three sentences of the full article: a _ wavelet set _ relative to dilation by an expansive ( all eigenvalues greater than 1 in absolute value ) real @xmath3 matrix @xmath4 is a set @xmath5 whose characteristic function @xmath6 is the fourier transform of an orthonormal wavelet .
that is , if @xmath7 then @xmath8 is an orthonormal basis for @xmath9 .
this definition is equivalent to the requirement that the set @xmath10 tiles @xmath11dimensional space ( almost everywhere ) both under translation by @xmath12 and under dilation by the transpose @xmath13 , so that @xmath14 @xmath15 while wavelet set wavelets are not well - localized , and thus not directly useful for applications , they have proven to be an essential tool in developing wavelet theory . in particular , wavelet set examples established that not all wavelets have an associated mra @xcite , and that single wavelets exist for an arbitrary expansive matrix in any dimension @xcite . smoothing and interpolation techniques have also used wavelet set wavelets to produce more well - localized examples ..
Please generate the next two sentences of the article | ( see e.g. @xcite , @xcite , @xcite , @xcite , @xcite , @xcite , @xcite . )
all of the early examples of wavelet sets for dilation by non - determinant 2 matrices in dimension greater than 1 were geometrically complicated , showing the fingerprints of the infinite iterated process used to construct them . |
3,554 | Suppose that you have an abstract for a scientific paper: we present here exact results for a one - dimensional gas , or fluid , of hard - sphere particles with attractive boundaries .
the particles , which can exchange with a bulk reservoir , mediate an interaction between the boundaries .
a two - dimensional lattice of such one - dimensional gas ` columns ' represents a discrete approximation of a three - dimensional gas of particles between two surfaces .
the effective particle - mediated interaction potential of the boundaries , or surfaces , is calculated from the grand - canonical partition function of the one - dimensional gas of particles , which is an extension of the well - studied tonks gas @xcite .
the effective interaction potential exhibits two minima .
the first minimum at boundary contact reflects depletion interactions , while the second minimum at separations close to the particle diameter results from a single adsorbed particle that crosslinks the two boundaries .
the second minimum is the global minimum for sufficiently large binding energies of the particles .
interestingly , the effective adhesion energy corresponding to this minimum is maximal at intermediate concentrations of the particles . .
And you have already written the first three sentences of the full article: the interactions of surfaces are often affected by nanoparticles or macromolecules in the surrounding medium .
non - adhesive particles cause attractive depletion interactions between the surfaces , since the excluded volume of the molecules depends on the surface separation @xcite .
adhesive particles , on the other hand , can directly bind two surfaces together if the surface separation is close to the particle diameter @xcite . in a recent letter @xcite.
Please generate the next two sentences of the article | , we have presented a general , statistical - mechanical model for two surfaces in contact with adhesive particles . in this model ,
the space between the surfaces is discretized into columns of the same diameter @xmath0 as the particles . |
3,555 | Suppose that you have an abstract for a scientific paper: brownian motion has been a pillar of statistical physics for more than a century , and recent high - frequency trading data have shed new light on microstructure of brownian motion in financial markets .
though evidences of trend - following behaviour of traders were indirectly shown in such trading data , the microscopic model has not been established so far by direct observation of trajectories for individual traders . in this paper
, we present a minimal microscopic model for financial brownian motion through an intensive analysis of trajectory data for all individuals in a foreign exchange market .
this model includes a novel empirical law quantifying traders trend - following behaviour that can create the inertial motion in market prices over short durations .
we present a systematic solution paralleling molecular kinetic theory to reveal mesoscopic and macroscopic dynamics of our model .
our model exhibits quantitative agreements with empirical results strongly supporting our analysis . .
And you have already written the first three sentences of the full article: in physics , the study of colloidal brownian motion has a long history beginning with einstein s famous paper @xcite in 1905 , and the understanding of its mechanism has been systematically developed in molecular kinetic theory @xcite .
recently , experimental developments have enabled researchers to observe a single trajectory itself of brownian motion @xcite , which engages physicists in quantitative modelling of sub - micrometer systems , such as molecular motors @xcite .
likewise , recent breakthroughs for computational technologies have enabled physicists to study microstructure of financial brownian motion in detail ..
Please generate the next two sentences of the article | they have applied their knowledge beyond material science and into studying in particular price movements in financial markets for about a quarter century . there
consequently appeared new approaches as mentioned below , in contrast to conventional mathematical finance where a priori theoretical dynamics is assumed @xcite . |
3,556 | Suppose that you have an abstract for a scientific paper: we assess electrical brain dynamics before , during , and after one - hundred human epileptic seizures with different anatomical onset locations by statistical and spectral properties of functionally defined networks .
we observe a concave - like temporal evolution of characteristic path length and cluster coefficient indicative of a movement from a more random toward a more regular and then back toward a more random functional topology .
surprisingly , synchronizability was significantly decreased during the seizure state but increased already prior to seizure end .
our findings underline the high relevance of studying complex systems from the view point of complex networks , which may help to gain deeper insights into the complicated dynamics underlying epileptic seizures .
* epilepsy represents one of the most common neurological disorders , second only to stroke .
patients live with a considerable risk to sustain serious or even fatal injury during seizures . in order to develop more efficient therapies the pathophysiology
underlying epileptic seizures should be better understood . in human epilepsy , however , the exact mechanisms underlying seizure termination are still as uncertain as are mechanisms underlying seizure initiation and spreading .
there is now growing evidence that an improved understanding of seizure dynamics can be achieved when considering epileptic seizures as network phenomena . by applying graph - theoretical concepts
, we analyzed seizures on the eeg from a large patient group and observed that a global increase of neuronal synchronization prior to seizure end may be promoted by the underlying functional topology of epileptic brain dynamics .
this may be considered as an emergent self - regulatory mechanism for seizure termination , providing clues as to how to efficiently control seizure networks . * .
And you have already written the first three sentences of the full article: complex networks can be observed in a wide variety of natural and man - made systems @xcite , and an important general problem is the relationship between the connection structure and the dynamics of these networks . with graph - theoretical approaches
, networks may be characterized using graphs , where nodes represent the elements of a complex system and edges their interactions . in the study of brain dynamics @xcite
, a node may represent the dynamics of a circumscribed brain region determined by electrophysiologic @xcite or imaging techniques @xcite ..
Please generate the next two sentences of the article | then two nodes are connected by an edge , or direct path , if the strength of their interaction increases above some threshold . among other structural ( or statistical ) parameters ,
the average shortest path length @xmath0 and the cluster coefficient @xmath1 are important characteristics of a graph @xcite . |
3,557 | Suppose that you have an abstract for a scientific paper: we apply two different numerical methods to solve for the boundstate of two 0-branes in three dimensions .
one method is developed by us in this work and we compare it to a method existing in the literature . in spite of considering only three dimensional minkowski space
we obtain interesting results which should give some basic understanding of the behaviour of 0-branes . .
And you have already written the first three sentences of the full article: d - branes are very important non - perturbative objects in string theory .
their existence is essential since they are needed , among other things , for various string theory dualities to work .
the most primitive definition of a d - brane is as a hyper surface on which open strings end . in this work.
Please generate the next two sentences of the article | we are interested only in d0-branes .
they play a particularly important role since they are the basic constituents of matrix theory @xcite , which , being a suggestion for a non - perturbative definition of string theory ( or m - theory @xcite ) , deserves particular attention . |
3,558 | Suppose that you have an abstract for a scientific paper: using the non - equilibrium quantum field theory , photon production from the coherently oscillating axion field in a flat robertson - walker cosmology is re - examined . first neglecting the debye screening of the baryon plasma to photons , we find that the axions will dissipate into photons via spinodal instability in addition to parametric resonance . as a result of the pseudo - scalar nature of the axion - photon coupling
, we observe a circular polarization asymmetry in the produced photons .
however , these effects are suppressed to an insignificant level in the expanding universe .
we then briefly discuss a systematic way of including the plasma effect which can further suppress the photon production .
we note that the formalism of the problem can be applied to any pseudo - scalar field coupled to photon in a thermal background in a general curved spacetime . .
And you have already written the first three sentences of the full article: it is compelling that most of the matter in the universe is in a form of non - baryonic cold dark matter .
if it exists , it would play an important role in the structure formation of the universe @xcite .
axions , the pseudo - goldstone bosons , are among the most promising candidates for the non - baryonic cold dark matter ..
Please generate the next two sentences of the article | they arise from the spontaneous breaking of a global @xmath0 symmetry of peccei and quinn ( pq ) , which is introduced to solve the strong cp problem of qcd @xcite . in the standard big - bang cosmology ,
after the spontaneous breakdown of the pq symmetry , the expectation value of the axion field ( i.e. the axionic condensate ) takes some random value on the interval @xmath1 $ ] and , is approximately constant over length scales which are smaller than the horizon size @xcite . |
3,559 | Suppose that you have an abstract for a scientific paper: we find that the motion of the valley electrons
electronic states close to the k and @xmath0 points of the brillouin zone is confined into two dimensions when the layers of mos@xmath1 form the 3r stacking , while in the 2h polytype the bands have dispersion in all the three dimensions .
according to our first - principles band structure calculations , the valley states have no interlayer hopping in 3r - mos@xmath1 , which is proved to be the consequence of the rotational symmetry of the bloch functions . by measuring the reflectivity spectra and analyzing an anisotropic hydrogen atom model
, we confirm that the valley excitons in 3r - mos@xmath1 have two - dimensional hydrogen - like spectral series , and the spreads of the wave function are smaller than the interlayer distance .
in contrast , the valley excitons in 2h - mos@xmath1 are well described by the three - dimensional model and thus not confined in a single layer .
our results indicate that the dimensionality of the valley degree of freedom can be controlled simply by the stacking geometry , which can be utilized in future valleytronics . .
And you have already written the first three sentences of the full article: the monolayer systems of group - vi dichalcogenides , @xmath2 ( @xmath3=mo , w ; @xmath4=s , se , te ) @xcite have received considerable interest as unique alternatives of graphene for their various intriguing properties @xcite : direct band gap of 2 ev @xcite , high photoluminescence yield @xcite , high on / off switching ratio in field effect transistors @xcite , and electric field - induced superconductivity @xcite .
most notably , their staggered - honeycomb - like lattice structure ( the structure and the unit cell are shown in fig . [
fig : mos2-struct ] ( a)(c ) ) hosts a model system for valley - dependent phenomena @xcite originally proposed for graphene @xcite ..
Please generate the next two sentences of the article | the bottom of the conduction band and the top of the valence band are located at the k points of the hexagonal brillouin zone in @xmath2 .
since the k and @xmath5@xmath6k points are not equivalent , the electronic states in the opposite pockets can carry an additional quantum number , the valley index . |
3,560 | Suppose that you have an abstract for a scientific paper: in this paper we develop an asymptotic analysis for formal and actual solutions of @xmath0-difference equations , under a regularity assumption , namely the non - collision and non - vanishing of the eigenvalues .
in particular , evaluations of regular solutions of regular @xmath0-difference equations have an exponential growth rate which can be computed from the @xmath0-difference equation .
the motivation for the paper comes from a problem in quantum topology , the hyperbolic volume conjecture , which states that a sequence on laurent polynomials ( the so - called colored jones function of a knot ) , appropriately evaluated , becomes a sequence of complex numbers that grows exponentially .
moreover , the exponential growth rate is proportional to the volume of the knot complement .
the connection of the hyperbolic volume conjecture with the paper comes from the fact that the colored jones function of a knot is a solution of a @xmath0-difference equation , as was proven by ttq .
le and the author . .
And you have already written the first three sentences of the full article: the goal of the paper is to intiate an approach to the hyperbolic volume conjecture , via asymptotics of solutions of difference equations with a small parameter .
the generalized volume conjecture links ( conjecturally ) the ( colored ) jones polynomial of a knot to hyperbolic geometry of its complement .
since the colored jones polynomial is a specific solution to a linear @xmath0-difference equation , it follows that the generalized volume conjecture is the wkb limit of a specific solution of a linear difference equation with a small parameter . motivated by this.
Please generate the next two sentences of the article | , we study wkb asymptotics of formal and actual solutions of difference equations with a small parameter , under certain regularity asymptions . a knot in 3-space is a smooth embedding of a circle , considered up to isotopy .
two of the simplest knots , the trefoil ( @xmath1 ) and the figure eight ( @xmath2 ) are shown here : @xmath3 by the very definition , knots are flexible objects defined up to isotopy , which allows the embedding to move in a smooth and arbitrary way as long as it does not cross itself . in algebraic topology , a common way of studying knots ( and more generally , spaces ) is to associate computable numerical invariants ( such as euler characteristic , or homology ) . |
3,561 | Suppose that you have an abstract for a scientific paper: ultra - cold atoms can be manipulated using microfabricated devices known as atom chips .
these have significant potential for applications in sensing , metrology and quantum information processing .
to date , the chips are loaded by transfer of atoms from an external , macroscopic magneto - optical trap ( mot ) into microscopic traps on the chip .
this transfer involves a series of steps , which complicate the experimental procedure and lead to atom losses . in this paper
we present a design for integrating a mot into a silicon wafer by combining a concave pyramidal mirror with a square wire loop .
we describe how an array of such traps has been fabricated and we present magnetic , thermal and optical properties of the chip .
atom chips , electrophoretic resist , magneto - optical traps , cavity patterning . .
And you have already written the first three sentences of the full article: atom chips are microfabricated devices that control electric , magnetic and optical fields in order to trap and manipulate cold atom clouds @xcite , @xcite , @xcite , @xcite and to form bose - einstein condensates @xcite , @xcite , @xcite .
potential applications include atomic clocks @xcite , atom interferometers @xcite , @xcite , and quantum information processors @xcite , @xcite .
silicon is one of several materials used as a substrate for atom chips ..
Please generate the next two sentences of the article | it is attractive for this purpose because its properties are well - known and fabrication techniques are highly developed .
the small scale of microfabricated current - carrying wires makes it easy to generate strong magnetic field gradients near the surface of the chip , forming tight traps for paramagnetic atoms . |
3,562 | Suppose that you have an abstract for a scientific paper: we present comparative measurements of the charge occupation and conductance of a gaas / algaas quantum dot .
the dot charge is measured with a capacitively coupled quantum point contact sensor . in the single - level coulomb blockade regime near equilibrium ,
charge and conductance signals are found to be proportional to each other .
we conclude that in this regime , the two signals give equivalent information about the quantum dot system . out of equilibrium
, we study the inelastic - cotunneling regime .
we compare the measured differential dot charge with an estimate assuming a dwell time of transmitted carriers on the dot given by @xmath0 , where @xmath1 is the blockade energy of first - order tunneling .
the measured signal is of a similar magnitude as the estimate , compatible with a picture of cotunneling as transmission through a virtual intermediate state with a short lifetime . .
And you have already written the first three sentences of the full article: quantum dots ( qds ) coupled to source and drain electrodes represent versatile and well - controlled systems for the study of mesoscopic transport @xcite .
the many aspects of electron tunneling through qds are typically studied by measuring either the qd _ conductance _ , or the qd _
charge occupation_. there are several techniques available for measuring the qd charge occupation , among them direct capacitance measurements @xcite , and the use of single - electron transistor @xcite and quantum point - contact @xcite ( qpc ) electrometers ..
Please generate the next two sentences of the article | more insight can be gained when _ combining _ charge and conductance measurements , and extracting information from both of them to obtain a more complete picture of the system . in the sequential tunneling regime of the qd ,
combined charge and conductance measurements can be used to determine the system timescales @xcite , whereas in a strong - coupling regime , such measurements reveal the effect of kondo correlations on the charge of a qd @xcite . in this paper , we present combined transport and qpc charge detection measurements in the cotunneling regime of a qd @xcite . |
3,563 | Suppose that you have an abstract for a scientific paper: we have performed laser cooling of mg@xmath0 ions confined in a penning trap .
the externally produced ions were captured in flight , stored and laser cooled .
laser - induced fluorescence was observed perpendicular to the cooling laser axis
. optical detection down to the single ion level together with electronic detection of the ion oscillations inside the penning trap have been used to acquire information on the ion storage time , ion number and ion temperature .
evidence for formation of ion crystals has been observed .
these investigations are an important prerequisite for sympathetic cooling of simultaneously stored highly - charged ions and precision laser spectroscopy of forbidden transitions in these . .
And you have already written the first three sentences of the full article: laser spectroscopy of optical transitions in highly charged ions ( hcis ) is a subject of considerable interest as it provides access to relativistic effects in few - electron systems and can be used to test bound - state qed in the extremely strong electric and magnetic fields in the vicinity of the ionic nucleus @xcite .
experimentally , such magnetic dipole ( m1 ) transitions in mid-@xmath1 hcis have first been studied in electron - beam ion traps ( ebits ) by laser excitation and fluorescence detection @xcite , yielding a relative accuracy of a few ppm for the determination of the wavelength .
direct laser spectroscopy of heavy ( high-@xmath1 ) hcis has so far only been performed at the experimental storage ring esr on hydrogen - like bismuth @xmath2bi@xmath3 @xcite and lead @xmath4pb@xmath5 @xcite . in both cases , the transition between the ground state hyperfine levels was induced by pulsed lasers and resonance fluorescence was recorded ..
Please generate the next two sentences of the article | these investigations have been extended to the ground - state hyperfine transition in lithium - like bismuth @xmath2bi@xmath6 , which has recently been observed in the experimental storage ring ( esr ) @xcite .
this measurement in combination with the measurement on hydrogen - like bismuth will allow the first determination of the so - called specific difference between the hyperfine splittings @xmath7 as suggested by shabaev and co - workers @xcite . |
3,564 | Suppose that you have an abstract for a scientific paper: we search for @xmath0 galaxies over @xmath1160 arcmin@xmath2 of wfc3/ir data in the chandra deep field south , using the public hudf09 , ers , and candels surveys , that reach to 5@xmath3 depths ranging from 26.9 to 29.4 in @xmath4 ab mag .
@xmath5 galaxy candidates are identified via @xmath6 colors and non - detections in any band blueward of @xmath7 .
spitzer irac photometry is key for separating the genuine high - z candidates from intermediate redshift ( @xmath8 ) galaxies with evolved or heavily dust obscured stellar populations . after removing 16 sources of intermediate brightness ( @xmath9 mag ) with strong irac detections ,
we only find one plausible @xmath0 galaxy candidate in the whole data set , previously reported in bouwens et al .
( 2011 ) .
the newer data cover a @xmath10 larger area and provide much stronger constraints on the evolution of the uv luminosity function ( lf ) .
if the evolution of the @xmath11 lfs is extrapolated to @xmath0 , six @xmath0 galaxies are expected in our data .
the detection of only one source suggests that the uv lf evolves at an accelerated rate before @xmath12 .
the luminosity density is found to increase by more than an order of magnitude in only @xmath13 myr from @xmath0 to @xmath12 .
this increase is @xmath14 larger than expected from the lower redshift extrapolation of the uv lf .
we are thus likely witnessing the first rapid build - up of galaxies in the heart of cosmic reionization .
future deep hst wfc3/ir data , reaching to well beyond 29 mag , can enable a more robust quantification of the accelerated evolution around @xmath0 . .
And you have already written the first three sentences of the full article: in recent years , great progress has been made in quantifying the evolution of the galaxy population at the end of cosmic reionization around @xmath15 .
deep hubble space telescope ( hst ) legacy fields , such as the hubble ultra - deep field ( hudf ; * ? ? ? * ) or goods @xcite , and wide area ground - based imaging , have made it possible to study the evolution of the uv luminosity function ( lf ) across @xmath16 to great accuracy ( e.g. * ? ? ?
* ; * ? ? ?.
Please generate the next two sentences of the article | * ; * ? ? ?
* ; * ? ? ? |
3,565 | Suppose that you have an abstract for a scientific paper: we calculate the optical @xmath0 luminosity function of the 2df galaxy redshift survey ( 2dfgrs ) for different subsets defined by their spectral properties . these spectrally selected subsets
are defined using a new parameter , @xmath1 , which is a linear combination of the first two projections derived from a principal component analysis .
this parameter @xmath1 identifies the average emission and absorption line strength in the galaxy rest - frame spectrum and hence is a useful indicator of the present star formation .
we use a total of 75,000 galaxies in our calculations , chosen from a sample of high signal - to - noise ratio , low redshift galaxies observed before january 2001 .
we find that there is a systematic steepening of the faint end slope ( @xmath2 ) as one moves from passive ( @xmath3 ) to active ( @xmath4 ) star - forming galaxies , and that there is also a corresponding faintening of the rest - frame characteristic magnitude @xmath5 ( from @xmath619.6 to @xmath619.2 ) .
we also show that the schechter function provides a poor fit to the quiescent ( type 1 ) lf for very faint galaxies ( @xmath7 fainter than @xmath616.0 ) , perhaps suggesting the presence of a significant dwarf population .
the luminosity functions presented here give a precise confirmation of the trends seen previously in a much smaller preliminary 2dfgrs sample , and in other surveys .
we also present a new procedure for determining self - consistent @xmath8-corrections and investigate possible fibre - aperture biases .
[ firstpage ] galaxies : distances and redshifts galaxies : elliptical and lenticular , cd galaxies : stellar content galaxies : formation galaxies : evolution .
And you have already written the first three sentences of the full article: it is well established that the measurement of the galaxy luminosity function ( lf ) is sensitive to the type of galaxy being sampled .
morphologically early - type galaxies tend to be systematically brighter than their late - type counterparts , resulting in lf estimates with significantly brighter @xmath9 and shallower faint end slope @xmath2 ( e.g. efstathiou , ellis & peterson 1988 ; loveday et al .
1992 ; blanton et al ..
Please generate the next two sentences of the article | similar trends are also present if one selects galaxies based on h@xmath2 equivalent widths ( loveday , tresse & maddox 1999 ) , [ oii ] equivalent widths ( ellis et al .
1996 ) or colour ( lin et al . 1996 ; marzke & da costa 1997 ) . |
3,566 | Suppose that you have an abstract for a scientific paper: we explore some foundational issues regarding the splitting of @xmath0-dimensional einstein field equations ( efe s ) with respect to timelike and spacelike ( @xmath0 - 1)-dimensional hypersurfaces , first without and then with thin matter sheets such as branes .
we begin to implement methodology , that is well - established for the gr cauchy and initial value problems ( cp and ivp ) , in the new field of gr - based braneworlds , identifying and comparing many different choices of procedure .
we abridge fragmentary parts of the literature of embeddings , putting the campbell magaard theorem into context .
we recollect and refine arguments why york and not elimination methods are used for the gr ivp .
we compile a list of numerous mathematical and physical impasses to using timelike splits , whereas spacelike splits are known to be well - behaved .
we however pursue both options to make contact with the current braneworld literature which is almost entirely based on timelike splits . in our study of timelike splits ,
we look at the shiromizu
maeda
sasaki braneworld by means of reformulations which emphasize different aspects from the original formulation .
we show that what remains of the york method in the timelike case generalizes heuristic bulk construction schemes .
we formulate timelike ( brane ) versions of the thin sandwich conjecture .
we discuss whether it is plausible to remove singularities by timelike embeddings .
we point out how the braneworld geodesic postulates lead to futher difficulties with the notion of singularities than in gr where these postulates are simpler .
having argued for the use of the spacelike split , we study how to progress to the construction of more general data sets for spaces partially bounded by branes .
boundary conditions are found and algorithms provided . working with ( finitely ) thick branes would appear to facilitate such a study .
* pde system approach to large extra dimensions + + * electronic address :....
And you have already written the first three sentences of the full article: a great deal of effort has recently gone into the study of higher - dimensional models as unified theories of gravity and fundamental matter fields .
the original interest in such models in kaluza
klein ( kk ) theory @xcite was revived by the important role of dimension 11 in supergravity @xcite and more recently by superstring theory @xcite and m - theory @xcite , which favour spacetimes of dimension 10 and 11 respectively ..
Please generate the next two sentences of the article | the usual ( kk ) argument for the apparent 4-dimensionality of spacetime is that the extra dimensions are compactified i.e curled up sufficiently small so as not to conflict with observation .
however , recently much attention has been placed instead on string - theory - inspired models with large extra dimensions @xcite in which most of the physics is confined or closely - bound to a lower - dimensional braneworld surrounded by a higher - dimensional bulk . though motivated by superstring and m - theories , many of these models @xcite are in fact formulated within the framework of ( higher - dimensional ) general relativity ( gr ) . among these are : 1 ) the second randall |
3,567 | Suppose that you have an abstract for a scientific paper: 8.0 cm 5.0 cm monolith is a proposed massive ( 34 kt ) magnetized tracking calorimeter at the gran sasso laboratory in italy , optimized for the detection of atmospheric muon neutrinos .
the main goal is to establish ( or reject ) the neutrino oscillation hypothesis through an explicit observation of the full first oscillation swing .
the @xmath0 sensitivity range for this measurement comfortably covers the complete super - kamiokande allowed region .
other measurements include studies of matter effects and the nc / cc and @xmath1 ratio , the study of cosmic ray muons in the multi - tev range , and auxiliary measurements from the cern to gran sasso neutrino beam .
depending on approval , data taking with part of the detector could start in 2004 .
the detector and its performance are described , and its potential later use as a neutrino factory detector is addressed . -1.6 cm 16.5 cm -1 cm a. geiser , hamburg university for the monolith collaboration ( * m*assive * o*bservatory for * n*eutrino * o*scillations or * li*mits on * th*eir existence ) bologna , bonn , cnr torino , columbia , lnf frascati , hamburg , humboldt berlin , inr moscow , laquila , lnf frascati , lngs gran sasso , mephi moscow , milano , mnster , napoli , roma , torino , tunis -0.7 in 6.0 in 9.0 in .
And you have already written the first three sentences of the full article: while the cumulative evidence for neutrino oscillations is very striking , the final proof that the observed anomalies are actually due to neutrino oscillations is still outstanding . in particular ,
the current observations of atmospheric neutrinos @xcite are all consistent with the hypothesis of maximal @xmath2 oscillations , but do not yet exclude some alternative unconventional explanations @xcite .
the main physics goal of the monolith experiment @xcite is to establish the occurrence of neutrino oscillations in atmospheric neutrinos through the explicit observation of the full first oscillation swing in @xmath2 disappearance @xcite , and to investigate and presumably exclude alternative explanations ..
Please generate the next two sentences of the article | this also yields a significantly improved measurement of the oscillation parameters with respect to previous measurements .
the monolith detector will be located at the gran sasso laboratory in italy , and the measurement of the oscillation pattern can be supplemented by measurements in the cern to gran sasso neutrino beam . |
3,568 | Suppose that you have an abstract for a scientific paper: we present a model for wave propagation in a monolayer of spheres on an elastic substrate .
the model , which considers sagittally polarized waves , includes : horizontal , vertical , and rotational degrees of freedom ; normal and shear coupling between the spheres and substrate , as well as between adjacent spheres ; and the effects of wave propagation in the elastic substrate . for a monolayer of interacting spheres ,
we find three contact resonances , whose frequencies are given by simple closed - form expressions .
for a monolayer of isolated spheres , only two resonances are present .
the contact resonances couple to surface acoustic waves in the substrate , leading to mode hybridization and `` avoided crossing '' phenomena .
we present dispersion curves for a monolayer of silica microspheres on a silica substrate , assuming adhesive , hertzian interactions , and compare calculations using an effective medium approximation to a discrete model of a monolayer on a rigid substrate . while the effective medium model does not account for discrete lattice effects at short wavelengths
, we find that it is well suited for describing the interaction between the monolayer and substrate in the long wavelength limit .
we suggest that a complete picture of the dynamics of a discrete monolayer adhered to an elastic substrate can be found using a combination of the results presented for the discrete and effective medium descriptions .
this model is potentially scalable for use with both micro- and macroscale systems , and offers the prospect of experimentally extracting contact stiffnesses from measurements of acoustic dispersion . .
And you have already written the first three sentences of the full article: granular media are simultaneously one of the most common and complex forms of matter on earth .
this complexity stems , in part , from heterogeneous structure and highly nonlinear particulate interactions @xcite . over the past thirty years
, mechanical wave propagation in ordered granular media has become an active field of research as it provides a setting for the broader understanding of granular media dynamics @xcite ..
Please generate the next two sentences of the article | ordered granular media have also been shown to enable a wide array of novel passive wave tailoring devices that leverage the nonlinear response stemming from the hertzian relationship between elastic particles in contact @xcite , in conjunction with dispersion induced by periodicity @xcite or local resonances @xcite .
experimental configurations used to study mechanical wave propagation in ordered granular media typically involve spherical particles confined by elastic media . |
3,569 | Suppose that you have an abstract for a scientific paper: we analyse extinction maps of nearby giant molecular clouds to forge a link between driving processes of turbulence and modes of star formation .
our investigation focuses on cloud structure in the column density range above the self shielding threshold of 1mag a@xmath0 and below the star formation threshold the regime in which turbulence is expected to dominate .
we identify clouds with shallow mass distributions as cluster forming .
clouds that form stars in a less clustered or isolated mode show a steeper mass distribution .
structure functions prove inadequate to distinguish between clouds of different star formation mode .
they may , however , suggest that the turbulence in the average cloud is governed by solenoidal forcing .
the same is found using the @xmath1-variance analysis which also indicates that clouds with a clustered mode of star formation show an enhanced component of compressive driving in the turbulent field .
thus , while star formation occurs in each cloud , independent of the turbulent driving mechanism , compressive forcing appears to be associated with the formation of stellar clusters .
[ firstpage ] star formation extinction
ism : clouds ism : dust ism : molecules .
And you have already written the first three sentences of the full article: stars form due to the local collapse of material in molecular clouds .
the conditions prior to the collapse result from a complex interplay between self - gravity , turbulence , magnetic fields and thermodynamics . understanding the effects of each of these influences leads to a better knowledge of how stars form . in this paper
we are interested in the role played by interstellar turbulence and it s effect on the structure of giant molecular clouds ( gmcs ) ..
Please generate the next two sentences of the article | the subject of astrophysical turbulence is complex and not fully understood , though there are many useful reviews on the topic ( e.g. elmegreen & scalo , scalo & elmegreen , brandenburg & nordlund @xcite ) .
here we are interested in comparing the structure of nearby gmcs to investigate whether it has an influence on the observed star formation properties . ultimately this might also be used to determine the nature of the turbulent field , i.e. driven by a compressive forcing or solenoidal driving ( e.g. federrath et al . ) . |
3,570 | Suppose that you have an abstract for a scientific paper: let @xmath0 be a random , degree @xmath1 polynomial whose roots are chosen independently according to the probability measure @xmath2 on the complex plane . for a deterministic point @xmath3 lying outside the support of @xmath2 , we show that almost surely the polynomial @xmath4 has a critical point at distance @xmath5 from @xmath3 . in other words ,
conditioning the random polynomials @xmath0 to have a root at @xmath3 , almost surely forces a critical point near @xmath3 .
more generally , we prove an analogous result for the critical points of @xmath6 , where @xmath7 are deterministic .
in addition , when @xmath8 , we show that the empirical distribution constructed from the critical points of @xmath9 converges to @xmath2 in probability as the degree tends to infinity , extending a recent result of kabluchko @xcite . .
And you have already written the first three sentences of the full article: this article deals with the relationship between zeros and critical points of random polynomials in one complex variable . recall that a _ critical point _ of a polynomial @xmath10 is a root of its derivative @xmath11
there are many results concerning the location of critical points of polynomials whose roots are known .
one of the most famous examples is the gauss .
Please generate the next two sentences of the article | lucas theorem , which offers a geometric connection between the roots of a polynomial and the roots of its derivative .
[ thm : gauss ] if @xmath10 is a non - constant polynomial with complex coefficients , then all zeros of @xmath11 belong to the convex hull of the set of zeros of @xmath10 . |
3,571 | Suppose that you have an abstract for a scientific paper: the dynamical formation of stellar - mass black hole - black hole binaries has long been a promising source of gravitational waves for the laser interferometer gravitational - wave observatory ( ligo ) .
mass segregation , gravitational focusing , and multibody dynamical interactions naturally increase the interaction rate between the most massive black holes in dense stellar systems , eventually leading them to merge . we find that dynamical interactions , particularly three - body binary formation , enhance the merger rate of black hole binaries with total mass @xmath0 roughly as @xmath1 , with @xmath2 .
we find that this relation holds mostly independently of the initial mass function , but the exact value depends on the degree of mass segregation .
the detection rate of such massive black hole binaries is only further enhanced by ligo s greater sensitivity to massive black hole binaries with @xmath3 .
we find that for power - law bh mass functions @xmath4 with @xmath5 , ligo is most likely to detect black hole binaries with a mass twice that of the maximum initial black hole mass and a mass ratio near one .
repeated mergers of black holes inside the cluster result in about @xmath6 of mergers being observed between two and three times the maximum initial black hole mass .
using these relations , one may be able to invert the observed distribution to the initial mass function with multiple detections of merging black hole binaries . .
And you have already written the first three sentences of the full article: after over two decades of development , the advanced laser interferometer gravitational - wave observatory ( aligo ) has directly detected gravitational waves from an inspiralling black hole - black hole ( bh - bh ) binary @xcite . through the precise measurement of the gravitational waves , aligo is capable of characterizing many properties of inspiralling binaries , including the total mass of the binary , @xmath0 , the mass ratio , @xmath7 , and the black holes spins .
the first detected bh - bh binary , gw150914 , had unusually high component masses @xmath8 in comparison to bh masses inferred for star - bh x - ray binaries @xcite . a second , less significant event , lvt151012 , also had high inferred masses @xmath9 @xcite .
aligo has finally opened a new window to our universe . along with other upcoming instruments virgo and kagra.
Please generate the next two sentences of the article | , aligo will allow us to probe the demographics of potentially hundreds of bh - bh binaries @xcite .
there are three primary pathways that lead to bh - bh binaries that can merge within the age of the universe , through binary evolution , through gas dynamics @xcite , and through stellar dynamics ( see * ? ? ? |
3,572 | Suppose that you have an abstract for a scientific paper: the small-@xmath0 contributions to the bjorken sum rule within double logarithmic @xmath1 approximation for different input parametrisations @xmath2 are presented .
analytical solutions of the evolution equations for full and truncated moments of the unintegrated structure function @xmath3 are used .
theoretical predictions for @xmath4 are compared with the smc small-@xmath0 data .
rough estimation of the slope @xmath5 , controlling the small-@xmath0 behaviour of @xmath6 from the smc data is performed .
double logarithmic terms @xmath7 become leading when @xmath8 and imply the singular behaviour of @xmath9 .
this seems to be confirmed by recent experimental smc and hermes data .
advantages of the unified @xmath1+lo dglap approach and the crucial role of the running coupling @xmath10 at low-@xmath0 are also discussed .
pacs 12.38 bx .
And you have already written the first three sentences of the full article: the results of sidis ( semi inclusive deep inelastic scattering ) experiments with polarised beams and targets enable the extraction of the spin dependent quark and gluon densities .
this powerful tool of studying the internal spin structure of the nucleon allows verification of sum rules .
one of them is the bjorken sum rule ( bsr ) @xcite , which refers to the first moment of the nonsinglet spin dependent structure function @xmath11 . because of @xmath12 flavour symmetry.
Please generate the next two sentences of the article | , bsr is regarded as exact .
thus all of estimations of polarised parton distributions should be performed under the assumption that the bsr is valid . |
3,573 | Suppose that you have an abstract for a scientific paper: we use high resolution numerical simulations to study whether gravitational instabilities within circumstellar discs can produce astrometrically detectable motion of the central star . for discs with masses of @xmath0 , which are permanantly stable against fragmentation , we find that the magnitude of the astrometric signal depends upon the efficiency of disc cooling .
short cooling times produce prominent filamentary spiral structures in the disc , and lead to stellar motions that are potentially observable with future high precision astrometric experiments . for a disc that is marginally unstable within radii of @xmath1 , we estimate astrometric displacements of @xmath2 on decade timescales for a star at a distance of 100 pc .
the predicted displacement is suppressed by a factor of several in more stable discs in which the cooling time exceeds the local dynamical time by an order of magnitude .
we find that the largest contribution comes from material in the outer regions of the disc and hence , in the most pessimistic scenario , the stellar motions caused by the disc could confuse astrometric searches for low mass planets orbiting at large radii .
they are , however , unlikely to present any complications in searches for embedded planets orbiting at small radii , relative to the disc size , or jupiter mass planets or greater orbiting at large radii .
psfig.sty accretion , accretion discs astrometry planetary systems : protoplanetary discs stars : formation stars : pre - main sequence .
And you have already written the first three sentences of the full article: high precision astrometry is a powerful tool to search for companions to nearby stars .
it also has the potential to discover significant numbers of extrasolar planetary systems . in this paper
we discuss the potential of astrometry as a probe of self - gravitating discs around pre - main sequence stars ..
Please generate the next two sentences of the article | a gaseous disc with sound speed @xmath3 , surface density @xmath4 , and epicyclic frequency @xmath5 is described as self - gravitating if the toomre ( 1964 ) @xmath6 parameter , @xmath7 is of order unity . in discs where self - gravity is important
, the outcome can either be fragmentation into one or more bound objects , or a quasi - steady state in which gravitational instabilities lead to the outward transport of angular momentum . |
3,574 | Suppose that you have an abstract for a scientific paper: we derive a closed expression for the number of nonnegative solutions of a certain system of linear diophantine equations .
the motivation comes from high energy physics where the nonnegative solutions play a crucial role in the perturbative calculation for a class of lagrangians describing the interaction of an atom with a boson field or a non - linear interaction of boson fields among themselves ( the so - called interacting @xmath0 models ) .
the linear system can be solved and the nonnegative solutions enumerated but a closed expression for the number of solutions is preferable to counting the solutions .
interestingly , the problem led to a construction of a simpler linear diophantine system whose nonnegative number of solutions turns out to be the magic constant .
[ theorem]corollary [ theorem]lemma [ theorem]proposition [ theorem]example [ theorem]conjecture .
And you have already written the first three sentences of the full article: linear diophantine equations and their systems are easy to solve .
there are three possibilities : either a system has no solution , one solution or infinitely many solutions . the case of one solution can be thought of as a special case of infinitely many solutions .
the method to distinguish the particular cases is known ( * ? ? ?.
Please generate the next two sentences of the article | * ch . 1 ) and
the issue can often be decided by inspection ( by a heuristic search for at least one solution ) . |
3,575 | Suppose that you have an abstract for a scientific paper: the steady current - voltage characteristics of ferromagnet - silicon - ferromagnet channels with tunable emitter and collector polarizations are investigated in the presence of spin blockade generalizing the model developed by pershin yu v and di ventra m ( 2008 _ phys .
rev .
_ b * 77 * 073301 ) .
the dependence of the critical current on both collector and emitter polarizations is obtained analytically .
it is found that the current amplitude in the channel can be effectively tuned by varying the difference between the collector and emitter ferromagnet polarizations which allows to perform the magnetic manipulation of the electrical current in wide class of both n- and p - doped , low- and high - ohmic semiconductor channels coupled to ferromagnetic leads . .
And you have already written the first three sentences of the full article: the progress of spintronics and physics of heterostructures which can be observed during the last years @xcite is focused on various physical phenomena , and one of them which attracts a considerable attention is the spin - dependent transport through semiconductor / spin - polarized junctions @xcite . the physics of carrier polarization and its influence on transport in composite structures such as semiconductor / ferromagnet has been studied both theoretically @xcite and experimentally @xcite .
one of the models describing the spin - resolved carrier concentrations and currents at the junction is the two - component drift - diffusion model @xcite which predicted highly nonlinear and saturating current - voltage dependence at a single semiconductor / feromagnet junction due to the effect of spin blockade @xcite . in this model
the detailed structure of the charge and current distribution at the junction area @xcite as well as the schottky barriers @xcite , the charge redistribution effects @xcite , and the bound states @xcite are not taken into consideration ..
Please generate the next two sentences of the article | still , the qualitative and distinguishable behaviour of current saturation due to the effect of spin blockade is reliably predicted under various system parameters such as the junction / semiconductor resistance ratio .
the spin blockade regime arises from the spatial distribution of the spin - minority carriers which can not enter the ferromagnet region and form a cloud near the junction which growth prevents the further increase of spin - majority carrier transport if the current exceeds a threshold value called the critical current . |
3,576 | Suppose that you have an abstract for a scientific paper: lattice effects in a cerium based clathrate compound ce@xmath0pd@xmath1ge@xmath2 with a cubic cr@xmath3c@xmath2-type structure have been investigated by ultrasonic and thermal expansion measurements .
elastic softenings of @xmath4 and @xmath5 proportional to the reciprocal temperature @xmath6 above @xmath7 k are well described in terms of the quadrupole susceptibility for the ground state @xmath8 quartet .
a huge softening of 50 % in @xmath4 and a spontaneous expansion @xmath9 along the [ 001 ] direction in particular indicate the ferroquadrupole ordering of @xmath10 below @xmath11 .
the elastic anomalies associated with the antiferromagnetic ordering at @xmath12 k and the incommensurate antiferromagnetic ordering are also found .
notable frequency dependence of @xmath5 around 10 k is accounted for by the debye - type dispersion indicating a @xmath13 rattling motion of an off - center ce ion along the [ 111 ] direction with eight fractionally occupied positions around the 4a site in a cage .
the thermally activated @xmath13 rattling motion obeying a relaxation time @xmath14exp@xmath15 with an attempt time @xmath16 sec and an activation energy @xmath17 k dies out with decreasing temperature , and then the off - center tunneling state of ce ion in the 4a - site cage will appear at low temperatures . .
And you have already written the first three sentences of the full article: the 4f - electronic systems with spin and orbital degrees of freedom in rare earth compounds frequently reveal electric quadrupole orderings in addition to magnetic dipole orderings at low temperatures .
the cubic compounds based on ce@xmath18 ion with a @xmath8 quartet ground state in particular have received much attention because the competitive phenomena associated with magnetic dipole , electric quadrupole and magnetic octupole degrees of freedom are expected .
the direct product of @xmath19 is reduced to a direct sum @xmath20 ..
Please generate the next two sentences of the article | the magnetic dipole @xmath21 , @xmath22 , @xmath23 belonging to @xmath24 symmetry are order parameters for magnetic orderings .
the quadrupole orderings of @xmath10 , @xmath25 with @xmath26 or @xmath27 , @xmath28 , @xmath29 with @xmath13 are interesting phenomena in the @xmath8 system . |
3,577 | Suppose that you have an abstract for a scientific paper: we consider a maximal extension of the hilbert - einstein action and analyze several interesting features of the theory .
more specifically , the motion is non - geodesic and takes place in the presence of an extra force .
these models could lead to some major differences , as compared to the predictions of general relativity or other modified theories of gravity , in several problems of current interest , such as cosmology , gravitational collapse or the generation of gravitational waves .
thus , the study of these phenomena may also provide some specific signatures and effects , which could distinguish and discriminate between the various gravitational models . .
And you have already written the first three sentences of the full article: a promising way to explain the late - time accelerated expansion of the universe is to assume that at large scales general relativity ( gr ) breaks down , and a more general action describes the gravitational field .
thus , in the latter context , infra - red modifications to gr have been extensively explored , where the consistency of various candidate models have been analysed ( see @xcite for a review ) .
note that the einstein field equation of gr was first derived from an action principle by hilbert , by adopting a linear function of the scalar curvature , @xmath0 , in the gravitational lagrangian density ..
Please generate the next two sentences of the article | the physical motivations for these modifications of gravity were related to the possibility of a more realistic representation of the gravitational fields near curvature singularities and to create some first order approximation for the quantum theory of gravitational fields , and more recently in an attempt to explain the late - time cosmic acceleration . in this context , a more general modification of the hilbert - einstein gravitational lagrangian density involving an arbitrary function of the scalar invariant , @xmath1 , has been extensively explored in the literature , and recently a maximal extension of the hilbert - einstein action has been proposed @xcite .
the action of the maximal extension of the hilbert - einstein action is given by @xcite @xmath3 where @xmath4 is an arbitrary function of the ricci scalar @xmath0 , and of the lagrangian density corresponding to matter , @xmath5 . |
3,578 | Suppose that you have an abstract for a scientific paper: we show that stable localized topological soliton textures ( skyrmions ) with @xmath0 topological charge @xmath1 exist in a classical 2d heisenberg model of a ferromagnet with uniaxial anisotropy . for this model
the soliton exist only if the number of bound magnons exceeds some threshold value @xmath2 depending on @xmath3 and the effective anisotropy constant @xmath4 .
we define soliton phase diagram as the dependence of threshold energies and bound magnons number on anisotropy constant .
the phase boundary lines are monotonous for both @xmath5 and @xmath6 , while the solitons with @xmath7 reveal peculiar nonmonotonous behavior , determining the transition regime from low to high topological charges .
in particular , the soliton energy per topological charge ( topological energy density ) achieves a minimum neither for @xmath5 nor high charges , but rather for intermediate values @xmath7 or @xmath8 . .
And you have already written the first three sentences of the full article: the studies of nonlinear excitations of two - dimensional ( 2d ) and quasi 2d correlated spin systems are an important issue of modern physics of magnetism , and can be useful for development of general soliton concepts .
@xcite the topological textures like localized solitons ( skyrmions @xcite ) or magnetic vortices make an important contribution to the thermodynamics of magnetically ordered systems @xcite or even determine the character of its ordering as in the case of berezinskii - kosterlitz - thouless transition .
@xcite last years the interest for two - dimensional solitons has grown since they are frequently realized as ground state in the finite - size mesoscopic magnetic samples , so - called magnetic dots . @xcite the most `` famous '' topological solitons are magnetic vortices having @xmath9 topological charge ..
Please generate the next two sentences of the article | these vortices are usually related to thermodynamic aspects of soliton physics .
@xcite also , they appear in mesoscopic nanostructures . @xcite easy - plane magnets with continuously degenerated ground state have vortices with the energy being logarithmically divergent as a function of system size . |
3,579 | Suppose that you have an abstract for a scientific paper: we discuss fits of cosmological dark energy models to the available data on high - redshift supernovae .
we consider a conventional model with cold dark matter and a cosmological constant ( @xmath0cdm ) , a model invoking super - horizon perturbations ( shcdm ) and models based on liouville strings in which dark energy is provided by a rolling dilaton field ( q - cosmology ) .
we show that a complete treatment of q - cosmology requires a careful discussion of non - equilibrium situations ( off - shell effects ) .
the two main high - redshift supernova data sets give compatible constraints on @xmath0cdm and the other models .
we recover the well - known result that @xmath0cdm fits very well the combined supernova data sets , as does the super - horizon model .
we discuss the model - dependent off - shell corrections to the q - cosmology model that are relevant to the supernova data , and show that this model fits the data equally well .
this analysis could be extended to other aspects of cosmological phenomenology , in particular to the cmb and baryon acoustic oscillations , which have so far been treated using on - shell models .
, , , observational cosmology , dark energy , supernovae98.80.es , 95.36.+x , 98.65.dx .
And you have already written the first three sentences of the full article: there is a plethora of astrophysical evidence today , from supernovae measurements , the spectrum of fluctuations in the cosmic microwave background @xcite , baryon oscillations and other cosmological data , indicating that the expansion of the universe is currently accelerating .
the energy budget of the universe seems to be dominated at the present epoch by a mysterious dark energy component , but the precise nature of this energy is still unknown .
many theoretical models provide possible explanations for the dark energy , ranging from a cosmological constant @xcite to super - horizon perturbations @xcite and time - varying quintessence scenarios @xcite , in which the dark energy is due to a smoothly varying ( scalar ) field which dominates cosmology in the present era , such as a time - dependent dilaton field @xcite ..
Please generate the next two sentences of the article | the current astrophysical data are capable of placing severe constraints on the nature of the dark energy , whose equation of state may be determined by means of an appropriate global fit . most of the analyses so far are based on effective four - dimensional robertson - walker universes , which satisfy on - shell dynamical equations of motion of the einstein - friedman form . even in modern approaches to brane cosmology , which are described by equations that deviate during early eras of the universe from the standard friedman equation ( which is linear in the energy density )
, the underlying dynamics is assumed to be of classical equilibrium ( on - shell ) nature , in the sense that it satisfies a set of equations of motion derived from the appropriate minimization of an effective space - time lagrangian . |
3,580 | Suppose that you have an abstract for a scientific paper: we discuss the possibility of extracting phase shifts from finite volume energies for meson - meson scattering , where the mesons are fermion - antifermion bound states of the massive schwinger model with su(2 ) flavour symmetry .
the existence of analytical strong coupling predictions for the mass spectrum and for the scattering phases makes it possible to test the reliability of numerical results . .
And you have already written the first three sentences of the full article: after the successful applications of lscher s method @xcite to the elastic scattering of _ elementary _ scalar and fermionic particles ( see , e.g. , @xcite ) , we have chosen the massive schwinger model ( qed@xmath0 ) with 2 flavours to determine scattering phases in meson - meson scattering .
similar to four - dimensional qcd , mesons occur because of confinement .
this two - dimensional model also exhibits charge screening and it possesses a nontrivial vacuum structure ..
Please generate the next two sentences of the article | moreover , there exist analytical predictions which enable us to test the numerical results .
lscher s relation connects elastic scattering phases in infinite volume and two - particle energies in finite volumes . in 2 dimensions it has the simple form @xmath1 using the energy - momentum relation , @xmath2 can be calculated from the mass and the two - particle energies , which are accessible to monte carlo simulations . |
3,581 | Suppose that you have an abstract for a scientific paper: astrometric measurements are presented for seven nearby stars with previously detected planets : six m dwarfs ( gj 317 , gj 667c , gj 581 , gj 849 , gj 876 , and gj 1214 ) and one k dwarf ( bd @xmath010 3166 ) .
measurements are also presented for six additional nearby m dwarfs without known planets , but which are more favorable to astrometric detections of low mass companions , as well as three binary systems for which we provide astrometric orbit solutions .
observations have baselines of three to thirteen years , and were made as part of the recons long - term astrometry and photometry program at the ctio / smarts 0.9 m telescope .
we provide trigonometric parallaxes and proper motions for all 16 systems , and perform an extensive analysis of the astrometric residuals to determine the minimum detectable companion mass for the 12 m dwarfs not having close stellar secondaries . for the six m dwarfs with known planets , we are not sensitive to planets , but can rule out the presence of all but the least massive brown dwarfs at periods of 2 12 years .
for the six more astrometrically favorable m dwarfs , we conclude that none have brown dwarf companions , and are sensitive to companions with masses as low as 1 @xmath1 for periods longer than two years .
in particular , we conclude that proxima centauri has no jovian companions at orbital periods of 2 12 years .
these results complement previously published m dwarf planet occurrence rates by providing astrometrically determined upper mass limits on potential super - jupiter companions at orbits of two years and longer . as part of a continuing survey ,
these results are consistent with the paucity of super - jupiter and brown dwarf companions we find among the over 250 red dwarfs within 25 pc observed longer than five years in our astrometric program . .
And you have already written the first three sentences of the full article: during the brief history of extrasolar planet investigations , our understanding of the relative populations of different types of planets has been limited by the observational biases of the techniques employed . with the advent of sophisticated transit searches and hypersensitive radial velocity measurements ,
significant progress has been made discovering various types of planets that orbit stars with periods up to a few years .
less progress has been made in discovering planets in longer orbits , and particularly around nearby m dwarfs , which account for at least 74% of the stellar population within 10 pc @xcite ..
Please generate the next two sentences of the article | m dwarfs offer fertile ground for companion searches , as @xcite have inferred that a high fraction of m dwarfs host terrestrial planets at short orbital periods .
less is known about the populations of jupiter - mass planets and brown dwarfs around m dwarfs , particularly at orbital periods longer than a few years . to understand how m dwarf planetary systems form and evolve , we must probe the full regime of companion masses and orbital periods . |
3,582 | Suppose that you have an abstract for a scientific paper: we use a suite of high - resolution n - body simulations to study the properties , abundance and clustering of high mass halos at high redshift , including their mass assembly histories and mergers .
we find that the analytic form which best fits the abundance of halos depends sensitively on the assumed definition of halo mass , with common definitions of halo mass differing by a factor of two for these low concentration , massive halos . a significant number of massive halos are undergoing rapid mass accretion , with major merger activity being common .
we compare the mergers and mass accretion histories to the extended press - schechter formalism .
we consider how major merger induced star formation or black hole accretion may change the distribution of photon production from collapsed halos , and hence reionization , using some simplified examples . in all of these ,
the photon distribution for a halo of a given mass acquires a large scatter .
if rare , high mass halos contribute significantly to the photon production rates , the scatter in photon production rate can translate into additional scatter in the sizes of ionized bubbles .
-1 cm .
And you have already written the first three sentences of the full article: observations of the anisotropy of the cosmic microwave background ( cmb ) radiation have given us unprecedented knowledge of the very early universe and dramatically confirmed the picture of large - scale structure as arising from the gravitational amplification of small perturbations in a universe with a significant cold dark matter component @xcite .
in this model the ionization history of the universe has two main events , a ` recombination ' at @xmath0 in which it went from ionized to neutral and a ` reionization ' during @xmath1 in which the radiation from early generations of collapsed objects was able to ionize the intergalactic medium .
the former event is strongly constrained by the cmb . a new generation of instruments will soon allow us to probe this second event : `` the end of the dark ages '' ( for reviews of reionization see e.g. * ? ? ? * ; * ? ? ?.
Please generate the next two sentences of the article | * ; * ? ? ?
* ; * ? ? ? |
3,583 | Suppose that you have an abstract for a scientific paper: active polarimetric imagery is a powerful tool for accessing the information present in a scene . indeed
, the polarimetric images obtained can reveal polarizing properties of the objects that are not avalaible using conventional imaging systems @xcite .
however , when coherent light is used to illuminate the scene , the images are degraded by speckle noise .
the polarization properties of a scene are characterized by the degree of polarization . in standard polarimetric imagery system , four intensity images are needed to estimate this degree @xcite .
if we assume the uncorrelation of the measurements , this number can be decreased to two images using the orthogonal state contrast image ( osci ) @xcite .
however , this approach appears too restrictive in some cases .
we thus propose in this paper a new statistical parametric method to estimate the degree of polarization assuming correlated measurements with only two intensity images .
the estimators obtained from four images , from the osci and from the proposed method , are compared using simulated polarimetric data degraded by speckle noise . .
And you have already written the first three sentences of the full article: polarimetric imagery consists in forming an image of the state of polarization of the light backscattered by a scene .
we consider in this paper that the scene is artificially illuminated with coherent light ( laser ) .
for example , this illumination is used in active imagery in order to combine night vision capability and to improve image resolution for a given aperture size . in practice , using a coherent illumination produces speckle noise that deteriorate the image @xcite ..
Please generate the next two sentences of the article | however , the backscattered light gives information about the capability of the scene to polarize or depolarize the emitted light and thus allows one to determine the medium that compose the scene .
these information can be described by a scalar parameter : the degree of polarization of light . |
3,584 | Suppose that you have an abstract for a scientific paper: we apply the optimal filter technique to sloan digital sky survey photometry around segue 1 and find that the outer parts of the cluster are distorted .
there is strong evidence for @xmath0 elongations of extra - tidal stars , extending both eastwards and southwestwards of the cluster .
the extensions have similar differential hess diagrams to segue 1 and a kolmogorov - smirnov test suggests a high probability that both come from the same parent distribution .
the location of segue 1 is close to crossings of the tidal wraps of the sagittarius stream . by extracting blue horizontal branch stars from sloan s spectral database , two kinematic features
are isolated and identified with different wraps of the sagittarius stream .
we show that segue 1 is moving with a velocity that is close to one of the wraps . at this location
, we estimate that there are enough sagittarius stars , indistinguishable from segue 1 stars , to inflate the velocity dispersion and hence the mass - to - light ratio .
all the available evidence is consistent with the interpretation that segue 1 is a star cluster , originally from the sagittarius galaxy , and now dissolving in the milky way .
-.6 in [ firstpage ] galaxies : kinematics and dynamics globular clusters : individual ( segue 1 ) .
And you have already written the first three sentences of the full article: segue 1 was discovered by @xcite as an overdensity of resolved stars in imaging data from the sloan digital sky survey ( sdss ) .
it is located at equatorial coordinates @xmath1 and has a heliocentric distance of @xmath2 kpc .
this corresponds to galactic coordinates @xmath3 , @xmath4 and a galactocentric distance of @xmath5 kpc ..
Please generate the next two sentences of the article | @xcite suggested that segue 1 was an extended globular cluster , possibly associated with the sagittarius stream . with its initially determined half - light radius of approximately @xmath6 pc
, it would be amongst the largest milky way globular clusters such as palomar 5 . |
3,585 | Suppose that you have an abstract for a scientific paper: heavy - tailed or power - law distributions are becoming increasingly common in biological literature . a wide range of biological data has been fitted to distributions with heavy tails .
many of these studies use simple fitting methods to find the parameters in the distribution , which can give highly misleading results .
the potential pitfalls that can occur when using these methods are pointed out , and a step - by - step guide to fitting power - law distributions and assessing their goodness - of - fit is offered . .
And you have already written the first three sentences of the full article: in the last fifteen years , power - law distributions , with their heavy - tailed and scale - invariant features , have become ubiquitous in scientific literature in general @xcite .
heavy - tailed distributions have been fitted to data from a wide range of sources , including ecological size spectra @xcite , dispersal functions for spores @xcite , seeds @xcite and birds @xcite , and animal foraging movements @xcite . in the latter case ,
the fit of a heavy - tailed distribution has been used as evidence that the optimal foraging strategy is a lvy walk with exponent @xmath0 @xcite ..
Please generate the next two sentences of the article | however , the appropriateness of heavy - tailed distributions for some of these data sets , and the methods used to fit them , have recently been questioned by edwards _
et al _ @xcite . |
3,586 | Suppose that you have an abstract for a scientific paper: following the suggestion of black(1997 ) that some massive extrasolar planets may be associated with the tail of the distribution of stellar companions , we investigate a scenario in which @xmath0 planetary mass objects are assumed to form rapidly through a fragmentation process occuring in a disc or protostellar envelope on a scale of 100 au .
these are assumed to have formed rapidly enough through gravitational instability or fragmentation that their orbits can undergo dynamical relaxation on a timescale @xmath1 orbits . under a wide range of initial conditions and assumptions
the relaxation process ends with either ( i ) one potential hot jupiter plus up to two external companions , i.e. planets orbiting near the outer edge of the initial distribution ; ( ii ) one or two external planets or even none at all ; ( iii ) one planet on an orbit with a semi major axis 10 to a 100 times smaller than the outer boundary radius of the inital distribution together with an external companion .
most of the other objects are ejected and could contribute to a population of free floating planets .
apart from the potential hot jupiters , all the bound objects are on highly eccentric orbits .
we found that , apart from the close orbiters , the probability of ending up with a planet orbiting at a given distance from the central star increases with the distance .
this is because of the tendency of the relaxation process to lead to collisions with the central star .
we discuss the application of these results to some of the more massive extrasolar planets .
giant planet formation extrasolar planets dynamical relaxation
orbital elements .
And you have already written the first three sentences of the full article: the recent discovery of extrasolar giant planets orbiting around nearby solar type stars ( marcy & butler 1998 , 2000 ; mayor & queloz 1995 ) has stimulated renewed interest in the theory of planet formation .
the objects observed so far have masses , @xmath2 , that are characteristic of giant planets , i.e. @xmath3 , m@xmath4 denoting a jupiter mass .
the orbital semi - major axes are in the range @xmath5 , and orbital eccentricities in the range @xmath6 ( marcy & butler 2000 ) ..
Please generate the next two sentences of the article | it is a challenge to formation theories to explain the observed masses and orbital element distributions .
there are two main theories of giant planet formation ( see papaloizou , terquem & nelson 1999 and references therein ) . |
3,587 | Suppose that you have an abstract for a scientific paper: this work presents fluid dynamics videos obtained via numerical ( cfd ) calculations using comsol ( finite elements method ) software , showing the evaporation of hfe7100 ( 3 m company refrigerant ) into a nitrogen gas flow along the liquid interface .
the overall temperature evolution and liquid motion , which is caused by surface - tension ( marangoni ) and buoyancy ( rayleigh ) instability mechanisms , are shown as well .
flow behavior in the liquid caused by the aforementioned instability mechanisms can be nicely seen .
finally , these observations are made for three liquid thicknesses in order to appreciate the qualitative influence of confinement . .
And you have already written the first three sentences of the full article: this work falls into a general framework which consists of observing the behavior of patterns and structures that can be formed after instability onset in an evaporating liquid layer . in previous work , we studied theoretical instability thresholds in pure fluids [ 1,2 ] and in binary mixtures [ 3,4 ] .
what is of interest here , is a two - dimensional numerical simulation study of the transient temperature and fluid motion in the liquid for a liquid evaporating into a nitrogen gas flow .
the chosen liquid is hfe7100 ( an electronic liquid produced by 3 m ) ..
Please generate the next two sentences of the article | the numerical ( cfd ) simulations are performed using the software comsol ( finite elements method ) . the evaporation causes the instability and the gas flow evacuates the liquid vapor .
the setup used for this numerical simulation is represented in fig . [ scheme ] and is inspired from the cimex experimental setup of esa [ 5 ] . |
3,588 | Suppose that you have an abstract for a scientific paper: both seasonal unit roots and seasonal heterogeneity are common in seasonal data . when testing seasonal unit roots under seasonal heterogeneity , it is unclear if we can apply tests designed for seasonal homogeneous settings , i.e. the hegy test ( hylleberg , engle , granger , and yoo , 1990 ) . in this paper ,
the validity of both augmented hegy test and unaugmented hegy test is analyzed .
the asymptotic null distributions of the statistics testing the single roots at @xmath0 or @xmath1 turn out to be standard and pivotal , but the asymptotic null distributions of the statistics testing any coexistence of roots at @xmath0 , @xmath1 , @xmath2 , or @xmath3 are non - standard , non - pivotal , and not directly pivotable .
therefore , the hegy tests are not directly applicable to the joint tests for the concurrence of the roots . as a remedy ,
we bootstrap augmented hegy with seasonal independent and identically distributed ( iid ) bootstrap , and unaugmented hegy with seasonal block bootstrap .
the consistency of both bootstrap procedures is established .
simulations indicate that for roots at @xmath0 and @xmath1 seasonal iid bootstrap augmented hegy test prevails , but for roots at @xmath4 seasonal block bootstrap unaugmented hegy test enjoys better performance .
* keywords : * seasonality , unit root , ar sieve bootstrap , block bootstrap , functional central limit theorem . .
And you have already written the first three sentences of the full article: seasonal unit roots and seasonal heterogeneity often coexist in seasonal data . hence , it is important to design seasonal unit root tests that allow for seasonal heterogeneity . in particular ,
consider quarterly data @xmath5 , @xmath6 generated by @xmath7 where @xmath8 are seasonally varying autoregressive ( ar ) filters , and @xmath9 have seasonally varying autocovariances . for more information on seasonal time
series , see ghysels and osborn ( 2001 ) , and franses and paap ( 2004 ) ..
Please generate the next two sentences of the article | now suppose @xmath10 is a weakly stationary vector - valued process , and for all @xmath11 , the roots of @xmath8 are on or outside the unit circle .
if for all @xmath12 , @xmath8 have roots at @xmath0 , @xmath1 , or @xmath4 , then respectively @xmath13 has stochastic trends with period @xmath14 , @xmath15 , or @xmath16 . to remove these stochastic trends , we need to test the roots at 1 , @xmath1 , or @xmath4 . to address this task , franses ( 1994 ) and |
3,589 | Suppose that you have an abstract for a scientific paper: we present a model for the @xmath0 helicity amplitudes , where @xmath1 is the nucleon and @xmath2 is a negative parity nucleon excitation , member of the @xmath3-multiplet @xmath4 $ ] .
the model combines the results from the single quark transition model for the helicity amplitudes with the results of the covariant spectator quark model for the @xmath5 and @xmath6 transitions . with the knowledge of the amplitudes @xmath7 and @xmath8 for those transitions we calculate three independent coefficients defined by the single quark transition model and make predictions for the helicity amplitudes associated with the @xmath9 , @xmath10 , @xmath11 , and @xmath12 transitions . in order to facilitate the comparison with future experimental data at high @xmath13
, we provide also simple parametrizations for the amplitudes , compatible with the expected falloff at high @xmath13 . .
And you have already written the first three sentences of the full article: one of the challenges in the modern physics is the description of the internal structure of the baryons and mesons .
the electromagnetic structure of the nucleon @xmath1 and the nucleon resonances @xmath2 can be accessed through the @xmath0 reactions , which depend of the ( photon ) momentum transfer squared @xmath13 @xcite .
the data associated with those transitions are represented in terms of helicity amplitudes and have been collected in the recent years at jefferson lab , with increasing @xmath13 @xcite ..
Please generate the next two sentences of the article | the new data demands the development of theoretical models based on the underlying structure of quarks and quark - antiquark states ( mesons ) @xcite .
those models may be used to guide future experiments as the ones planned for the jlab12 gev upgrade , particularly for resonances in the second and third resonance region [ energy @xmath14@xmath15 gev ] ( see figure [ figsigmaw ] ) @xcite . in that region |
3,590 | Suppose that you have an abstract for a scientific paper: this paper discusses noisy index coding problem over gaussian broadcast channel .
we propose a technique for mapping the index coded bits to m - qam symbols such that the receivers whose side information satisfies certain conditions get coding gain , which we call the * qam side information coding gain*. we compare this with the psk side information coding gain , which was discussed in @xcite .
index coding , awgn broadcast channel , m@xmath0qam , qam side information coding gain . .
And you have already written the first three sentences of the full article: the problem of index coding over noiseless broadcast channels was introduced in @xcite and has been well studied @xcite - @xcite .
it involves a single source and a set of caching receivers .
each of the receivers wants a subset of the set of messages transmitted by the source and knows another non - intersecting subset of messages a priori as side information ..
Please generate the next two sentences of the article | the problem is to minimize the number of binary transmissions required to satisfy the demands of all the receivers , which amounts to minimizing the bandwidth required .
an index coding problem @xmath1 , involves a single source , @xmath2 that wishes to send a set of @xmath3 messages @xmath4 to a set of @xmath5 receivers , @xmath6 . |
3,591 | Suppose that you have an abstract for a scientific paper: we summarize our recent results @xcite for the induced exchange interaction due to thermal bosonic environment ( bath ) which also generates quantum noise .
our focus here is on the onset of the interaction .
we demonstrate that the induced interaction can be used to manipulate and create entanglement over time scales sufficiently large for controlling the two - qubit system for quantum computing applications , though ultimately the noise effects will dominate . .
And you have already written the first three sentences of the full article: recently it was demonstrated @xcite that two qubits subject to common thermal bosonic environment ( bath ) can develop considerable entanglement .
a similar result has also been obtained for qubits interacting via fermionic environment @xcite . here
we review our results on the derivation of the induced exchange interaction and quantum noise in a unified formulation @xcite , focusing the presentation on the onset and development of the cross - qubit correlations due to the bath ..
Please generate the next two sentences of the article | we consider a 1d channel model for the bath , motivated by recent experiments @xcite , and allow bosons ( e.g. phonons , photons ) to propagate along a single direction with wave vector @xmath0 and dispersion @xmath1 .
more general results are available in @xcite . |
3,592 | Suppose that you have an abstract for a scientific paper: we study the temporal and energy spectral properties of the unique neutron star low - mass x - ray binary . after assuming the hb / nb vertex as a reference position of accretion rate ,
the horizontal branch oscillation ( hbo ) of the hb / nb vertex is roughly 50 hz .
it indicates that the hbo is independent with the accretion rate or the source intensity .
the spectral analysis shows @xmath0 in the hb / nb vertex and @xmath1 in the nb / fb vertex , which implies that different accretion rate may be produced in the hb / nb vertex and the nb / fb vertex .
the comptonization component could be fitted by constrained broken power law ( cbpl ) or nthcomp .
different with , the frequencies of hbo positively correlate with the inner disk radius , which contradict with the prediction of lense - thirring precession model .
, both in the cyg - like phase and in the sco - like phase , follows a positive correlation between the break frequency of broad band noise and the characteristic frequency of hbo , which is called the w - k relation .
an anticorrelation between the frequency of hbo and photon energy is observed .
moreover , the rms of hbo increases with photon energy till @xmath2 .
we discuss the possible origin of hbo from corona in . .
And you have already written the first three sentences of the full article: low mass x - ray binary ( lmxb ) is composed of a compact object ( neutron star or black hole ) accreting matter from its low mass companion star ( @xmath3 ) . according to the x - ray spectral proporties and rapid timing variabilities , the neutron star ( ns ) lmxbs are usually classified as the z sources and the atoll sources .
they are named after the shapes which display in x - ray color - color diagram ( cd ) or hardness - intensity diagrams ( hid ) .
the z sources produce approximate eddington luminosities with soft x - ray spectra , whereas atoll sources produce a lower luminosities in the range @xmath4 * ? ? ?.
Please generate the next two sentences of the article | a typical z source track shows three branches , from top to bottom , which are usually called the horizontal branch ( hb ) , the normal branch ( nb ) , and the flaring branch ( fb ; @xcite ) , respectively . for atoll sources , the three branches are called extreme island , island , and banana state .
based on the orientation of branches , six typical z sources are further divided into the cyg- like z sources ( , and ) with a horizontal hb ( z "- shaped tracks ) and the sco - like z sources ( , , and ) with a vertical hb ( @xmath5"-shaped tracks ) . the black hole ( bh ) and |
3,593 | Suppose that you have an abstract for a scientific paper: in this study we present high - resolution visible multi - object spectrograph integral field unit spectroscopy ( vimos - ifu ) of the extremely metal - poor hii / blue compact dwarf ( bcd ) galaxy tol 65 .
the optical appearance of this galaxy shows clearly a cometary morphology with a bright main body and an extended and diffuse stellar tail .
we focus on the detection of metallicity gradients or inhomogeneities as expected if the ongoing star - formation activity is sustained by the infall / accretion of metal - poor gas .
no evidences of significant spatial variations of abundances were found within our uncertainties . however , our findings show a slight anticorrelation between gas metallicity and star - formation rate at spaxel scales , in the sense that high star - formation is found in regions of low - metallicity , but the scatter in this relation indicates that the metals are almost fully diluted .
our observations show the presence of extended h@xmath0 emission in the stellar tail of the galaxy .
we estimated that the mass of the ionized gas in the tail m(hii)@xmath11.7@xmath210@xmath3 m@xmath4 corresponds with @xmath524 per cent of the total mass of the ionized gas in the galaxy .
we found that the h@xmath0 velocity dispersion of the main body and the tail of the galaxy are comparable with the one found in the neutral gas by previous studies .
this suggests that the ionized gas still retains the kinematic memory of its parental cloud and likely a common origin . finally , we suggest that the infall / accretion of cold gas from the outskirts of the galaxy and/or minor merger / interaction may have produced the almost flat abundance gradient and the cometary morphology in tol 65 .
[ firstpage ] galaxies : dwarf galaxies : individual : tol 65 ( tol 1223 - 359 , eso380-g027 ) galaxies : ism galaxies : abundances . .
And you have already written the first three sentences of the full article: it is well established that interactions and/or galaxy collisions represent an important stage in the evolution of galaxies ( e.g. * ? ? ? * ; * ? ? ?
* ; * ? ? ?
* ; * ? ? ?.
Please generate the next two sentences of the article | numerous studies show clear indications of the importance of those external mechanisms for the enhancement of star - formation and its effects in the chemical enrichment of galaxies .
in particular , in major merger of massive galaxies the preexisting gas metallicity can be substantially diluted by the inflow of metal poor gas from the outskirts to the nucleus ( e.g. * ? ? ? |
3,594 | Suppose that you have an abstract for a scientific paper: the exact mechanism behind type ia supernovae ( sne - ia ) and the nature of the progenitors is poorly understood , although several theories vie for supremacy .
their secured importance to the study of cosmology necessitates a resolution to this problem .
observations of nearby sne - ia are therefore critical to determine which theory , if any , is the correct one .
sn 2014j discovered at a relatively close 3.5 mpc in the galaxy m82 provides such an opportunity . in this paper
we give specific predictions for sn 2014j in the context of the quark nova ia ( qn - ia ) model .
predictions include x - ray luminosities just prior and hundreds of days after the explosion , light curve glitches " , neutrino emission , heavy element creation , and gravitational signatures . .
And you have already written the first three sentences of the full article: type ia supernovae ( sne - ia ) are thought to be standardizable " candles capable of measuring cosmological distances .
their utility in this sense has been used over the past two decades to first discover ( riess et al .
1998 ; perlmutter et al . 1999 ) and then study the accelerated expansion of the universe ; the results from which have deeply shaken our perception of nature . despite their overwhelming acceptance as standardizable " candles , the mechanism and nature of the progenitors behind the sn - ia explosion are poorly understood ..
Please generate the next two sentences of the article | we understand from their spectra that sne - ia are explosions of carbon / oxygen white dwarfs ( cowds ) ; how they actually explode is still an area of intense research .
two theories lead the fray , both requiring the accumulation of mass onto the white dwarf ( wd ) leading to a thermonuclear explosion : the single - degenerate ( sd ) channel is the accretion onto the wd from a non - degenerate companion ( whelan & iben 1973 ) and the double - degenerate ( dd ) channel provides the mass from the merger of two wds ( iben & tutukov 1994 ; webbink 1984 ) . |
3,595 | Suppose that you have an abstract for a scientific paper: we propose a method of studying the continuous percolation of aligned objects as a limit of a corresponding discrete model .
we show that the convergence of a discrete model to its continuous limit is controlled by a power - law dependency with a universal exponent @xmath0 .
this allows us to estimate the continuous percolation thresholds in a model of aligned hypercubes in dimensions @xmath1 with accuracy far better than that attained using any other method before .
we also report improved values of the correlation length critical exponent @xmath2 in dimensions @xmath3 and the values of several universal wrapping probabilities for @xmath4 .
_ keywords _ : percolation threshold ; continuous percolation ; critical exponents ; finite - size scaling , percolation wrapping probabilities .
And you have already written the first three sentences of the full article: while advances in two - dimensional ( 2d ) percolation have recently allowed to determine the site percolation threshold on the square lattice with an astonishing accuracy of 14 significant digits @xcite and many critical exponents in 2d have been known exactly for decades @xcite , the progress in higher dimensions is far slower .
the main reason for this is that the two theoretical concepts that proved particularly fruitful in percolation theory , conformal field theory and duality , are useful only in 2d systems , and the thresholds in higher dimensions are known only from simulations .
the site and bond percolation thresholds in dimensions @xmath5 are known with accuracy of at least 6 significant digits @xcite , but for more complicated lattices , e.g. fcc , bcc or diamond lattices @xcite , complex neighborhoods @xcite , or continuum percolation models @xcite this accuracy is often far from satisfactory . moreover , even though the upper critical dimension is known to be @xmath6 @xcite , numerical estimates of the critical exponents for @xmath7 are still rather poor ..
Please generate the next two sentences of the article | continuous percolation of aligned objects can be regarded as a limit of a corresponding discrete model .
using this fact , we recently improved the accuracy of numerical estimates of continuous percolation of aligned cubes ( @xmath8 ) @xcite . |
3,596 | Suppose that you have an abstract for a scientific paper: conventional thermo - statistics address infinite homogeneous systems within the canonical ensemble .
( only in this case this is equivalent to the fundamental microcanonical ensemble . )
however , some 170 years ago the original motivation of thermodynamics was the description of steam engines , i.e. boiling water .
its essential physics is the separation of the gas phase from the liquid .
of course , boiling water is inhomogeneous and as such can not be treated by conventional thermo - statistics .
then it is not astonishing , that a phase transition of first order is signaled canonically by a yang - lee singularity . _
thus it is only treated correctly by microcanonical boltzmann - planck statistics_. it turns out that the boltzmann - planck statistics is much richer and gives fundamental insight into statistical mechanics and especially into entropy .
this can be done to a far extend rigorously and analytically .
as no extensivity , no thermodynamic limit , no concavity , no homogeneity is needed , it also applies to astro - physical systems .
the deep and essential difference between `` extensive '' and `` intensive '' control parameters , i.e. microcanonical and canonical statistics , is exemplified by rotating , self - gravitating systems . in the present paper
the necessary appearance of a convex entropy @xmath0 and negative heat capacity at phase separation in small as well macroscopic systems independently of the range of the force is pointed out .
thus the old puzzle of stellar statistics is finally solved , the appearance of negative heat capacity which is forbidden and can not appear in the canonical formalism .
presented at the nbs2005 at the observatoire de paris microcanonical statistics , first order transitions , phase separation , steam engines , negative heat capacity , self - gravitating and rotating stellar systems 01.55.+b,04.40.-b , 05.20.gg , 64.60.-i,65 , 47.27.eb , 97.80.-d .
And you have already written the first three sentences of the full article: conventional statistical mechanics addresses homogeneous macroscopic systems in the thermodynamic limit .
these are traditionally treated in canonical ensembles controlled by intensive temperature @xmath1 , chemical potential @xmath2 and/or pressure @xmath3 . in the canonical ensemble
the heat capacity is given by the fluctuation of the energy @xmath4 ..
Please generate the next two sentences of the article | as in astro - physics the heat capacity is often negative it is immediately clear that astro - physical systems are not in the canonical ensemble .
this was often considered as a paradoxical feature of the statistics of self - gravitating systems . here |
3,597 | Suppose that you have an abstract for a scientific paper: a long ( 155 hours ) _ asca _ observation was performed of two ultra luminous compact x - ray sources , source 1 and source 2 , in the spiral galaxy ic 342 . while source 1 that was in a hard spectral state varied little , source 2 that was in its soft spectral state varied significantly on a time scale of about one day .
the rms variation amplitude amounts to 5% in the 210 kev band , but is less than 4% in 0.72 kev .
the variation involves statistically significant changes in the parameters describing multi - color disk blackbody emission from this source .
the variation is possibly periodic , with a period of either @xmath0 hours or @xmath1 hours
. both are consistent with the orbital period of a semi - detached binary formed by a black hole and a main - sequence star of several tens solar masses .
these results reinforce the interpretation of these x - ray objects in terms of accreting massive stellar black holes . .
And you have already written the first three sentences of the full article: ultra luminous compact x - ray sources ( ulxs ; makishima et al .
2000 ) are objects often seen in off - center regions of nearby spiral galaxies , and exhibit x - ray luminosities by far exceeding the eddington limit for a neutron star ( fabbiano . 1989 ; read et al .
1997 ; lira et al ..
Please generate the next two sentences of the article | 2000 ; roberts & warwick 2000 ; bauer et al . 2001 ; fabbiano et al . 2001 ; strickland et al . 2001 ) . as reported by many _
asca _ observers ( colbert & mushotzky 1999 ; kotoku et al . 2000 ; makishima et al . 2000 and references therein ) , the spectra of a majority of ulxs |
3,598 | Suppose that you have an abstract for a scientific paper: we study how electron - electron ( e - e ) interactions affect the current carried by excited electrons and holes in dirac systems such as graphene or topological insulators .
we find that the current shows distinctly different behavior for e - e collisions involving the electron or the hole .
most surprisingly , for positive fermi energy , collisions of the electrons can substantially increase the current .
this remarkable amplification of the current can be of the order of @xmath0 per scattering event .
it also causes a strong suppression of the overall current relaxation rate of a photoexcited electron - hole pair , with the amplification of the electron current making up for a fast decay of the hole current . _
introduction._dirac systems like graphene and topological insulators ( tis ) are a central research topic in condensed matter physics .
the easy fabrication process of graphene @xcite and the discovery of a variety of materials that are 2d @xcite or 3d @xcite tis are but two reasons why dirac systems are studied intensively . because of their linear dispersion and unique helical ( pseudo)spin structure , graphene and tis might be valuable materials for spintronic devices @xcite .
in addition , graphene and tis are promising systems for applications in the rising field of optoelectronics , for instance as transparent conductors or photodetectors @xcite .
photocurrents provide an interesting probe of the optoelectronic properties of dirac materials , and have been measured in both systems @xcite .
their magnitude is governed by a competition between carrier excitation which is asymmetric in momentum space and current relaxation @xcite .
while there has been extensive research on energy relaxation of excited electrons both theoretically @xcite and experimentally @xcite , current relaxation of photoexcited carriers in dirac systems remains much less unexplored @xcite .
in general , current relaxation occurs through impurity , electron - phonon , or electron - electron ( e -....
And you have already written the first three sentences of the full article: a. details of the geometric argument for the current increase or decrease b. evaluation of the energy conservation @xmath71-function c. identification of distinct scattering processes in the asymptotic behavior of the rate of change of the current d. asymptotic behavior of the rate of change of the current for large excitation energies e. definition of the mean change of the current per electron scattering event
the dashed circles indicate constant energy contours and are a guide to the eye .
processes where the final states @xmath25 and @xmath26 are both either in the lower or upper band are similar to the case of @xmath90 and do not affect the current ..
Please generate the next two sentences of the article | b ) for @xmath51 the allowed scattering processes can also be represented by an ellipse .
@xmath91 is the length of the semi - major axis and @xmath92 is the distance between the focal points . |
3,599 | Suppose that you have an abstract for a scientific paper: it is questionable that grover algorithm may be more valuable than a classical one , when a partial information is given in a unstructured database . in this letter , to consider quantum search when a partial information is given , we replace the fourier transform in the grover algorithm with the haar wavelet transform .
we then , given a partial information @xmath0 to a unstructured database of size @xmath1 , show that there is the improved speedup , @xmath2 .
suppose that we have a problem of finding a desired one of unstructured @xmath1 items .
it is known that a classical search algrithm may take @xmath3 times , but the fast quantum search algorithm provides the quadratic speedup , @xmath4.@xcite the quantum algorithm whose central idea is amplitude amplification was first provided by grover in 1996.@xcite@xcite it is well - known that grover algorithm is 1)optimal in the context of applying unitary operators repeatdly and 2)efficient in searching a target of a unstructured database .
however , it is not evident that , when a partial information is given , the grover algorithm is still more valuable than a classical one . in this letter , we provide the quantum search algorithm which is able to benefit from a partial information .
the key building block in our construction is the ( haar ) wavelet transform instead of the fourier transform in the grover algorithm .
+ let us first consider the grover algorithm .
a bijection between a database and quantum states is necessary before applying the grover algorithm .
if a superposition of @xmath1 states is initially prepared , the grover algorithm amplifies the amplitude of the target state up to around one , while those of other states dwindle down to nearly zeros .
the amplitude amplification is performed by two inversion operations : inversion about the target by the oracle and inversion about the initial state by the fourier transform .
noting the fact that two simultaneous reflections about two mirrors crossing by an angle @xmath5....
And you have already written the first three sentences of the full article: j. bae is supported in part by the hanyang university fellowship and y. kwon is supported in part by the fund of hanyang university ..
Please generate the next two sentences of the article |
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