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list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0705.2298 | Olivier Finkel | Olivier Finkel (LIP), Stevo Todorcevic (ELM, DEPT MATHS) | Local Sentences and Mahlo Cardinals | null | Mathematical Logic Quaterly 53, 6 (2007) 558-563 | null | null | math.LO | null | Local sentences were introduced by J.-P. Ressayre who proved certain
remarkable stretching theorems establishing the equivalence between the
existence of finite models for these sentences and the existence of some
infinite well ordered models. Two of these stretching theorems were only proved
under certain large cardinal axioms but the question of their exact
(consistency) strength was left open in [O. Finkel and J.-P. Ressayre,
Stretchings, Journal of Symbolic Logic, Volume 61 (2), 1996, p. 563-585 ].
Here, we solve this problem, using a combinatorial result of J. H. Schmerl. In
fact, we show that the stretching principles are equivalent to the existence of
n-Mahlo cardinals for appropriate integers n. This is done by proving first
that for each integer n, there is a local sentence phi_n which has well ordered
models of order type alpha, for every infinite ordinal alpha > omega which is
not an n-Mahlo cardinal.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 08:39:21 GMT"
}
] | 2019-08-15T00:00:00 | [
[
"Finkel",
"Olivier",
"",
"LIP"
],
[
"Todorcevic",
"Stevo",
"",
"ELM, DEPT MATHS"
]
] |
0705.2299 | Dario Zappala | V. Branchina, D. Zappal\`a | Time evolution of T_{\mu\nu} and the cosmological constant problem | 11 Pages, revised version | Gen.Rel.Grav.42:141-154,2010 | 10.1007/s10714-009-0822-x | null | hep-ph astro-ph.CO gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the cosmic time evolution of an effective quantum field theory
energy-momentum tensor T_{\mu\nu} and show that, as a consequence of the
effective nature of the theory, the structure of T_{\mu\nu} is such that the
vacuum energy decreases with time. We find that the zero point energy at
present time is washed out by the cosmological evolution. The implications of
this finding for the cosmological constant problem are investigated.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 08:52:55 GMT"
},
{
"version": "v2",
"created": "Fri, 6 Jul 2007 14:59:16 GMT"
},
{
"version": "v3",
"created": "Thu, 11 Sep 2008 09:12:29 GMT"
}
] | 2010-05-27T00:00:00 | [
[
"Branchina",
"V.",
""
],
[
"Zappalà",
"D.",
""
]
] |
0705.2300 | Giovanni Carraro dr | Sandro Villanova (Padova), Gustavo Baume (La Plata), Giovanni Carraro
(Padova) | The anticenter old open cluster NGC 1883: radial velocity and
metallicity | 8 pages, 7 eps figures (some degraded in resolution), accepted for
publication in MNRAS | Mon.Not.Roy.Astron.Soc.379:1089-1096,2007 | 10.1111/j.1365-2966.2007.11986.x | null | astro-ph | null | Having already reported on the first photometric study of the
intermediate-age open cluster NGC 1883 (Carraro et al. 2003), we present in
this paper the first spectroscopic multi-epoch investigation of a sample of
evolved stars in the same cluster. The aim is to derive the cluster membership,
velocity and metallicity, and discuss recent claims in the literature (Tadross
2005) that NGC 1883 is as metal poor as globular clusters in the Halo. Besides,
being one of the few outer Galactic disk intermediate-age open clusters known
so far, it is an ideal target to improve our knowledge of the Galactic disk
radial abundance gradient, that is a basic ingredient for any chemical
evolution model of the Milky Way. The new data we obtained allow us to put NGC
1883's basic parameters more reliable. We find that the cluster has a mean
metallicity of [Fe/H] = -0.20$\pm$0.22, from which we infer an age
(650$^{+70}_{-70}$ Myr) close to the Hyades one and a Galactocentric distance
of 12.3$^{+0.4}_{-0.2}$ kpc. The metal abundance, kinematics, and position make
NGC 1883 a genuine outer disk intermediate-age open cluster. We confirm that in
the outer Galactic disk the abundance gradient is shallower than in the solar
vicinity.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 08:59:53 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Villanova",
"Sandro",
"",
"Padova"
],
[
"Baume",
"Gustavo",
"",
"La Plata"
],
[
"Carraro",
"Giovanni",
"",
"Padova"
]
] |
0705.2301 | John J. Oh | Seungjoon Hyun, Jaehoon Jeong, Wontae Kim, and John J. Oh | Withrawn paper | This paper has been withdrawn | null | null | null | gr-qc astro-ph hep-th | null | This paper has been withdrawn by the authors due to some fatal errors in the
analysis.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:00:32 GMT"
},
{
"version": "v2",
"created": "Wed, 5 Mar 2008 05:18:49 GMT"
}
] | 2008-03-05T00:00:00 | [
[
"Hyun",
"Seungjoon",
""
],
[
"Jeong",
"Jaehoon",
""
],
[
"Kim",
"Wontae",
""
],
[
"Oh",
"John J.",
""
]
] |
0705.2302 | David \v{S}i\v{s}ka | Istvan Gyongy, David Siska | On randomized stopping | Published in at http://dx.doi.org/10.3150/07-BEJ108 the Bernoulli
(http://isi.cbs.nl/bernoulli/) by the International Statistical
Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm) | Bernoulli 2008, Vol. 14, No. 2, 352-361 | 10.3150/07-BEJ108 | IMS-BEJ-BEJ108 | math.PR math.OC | null | A general result on the method of randomized stopping is proved. It is
applied to optimal stopping of controlled diffusion processes with unbounded
coefficients to reduce it to an optimal control problem without stopping. This
is motivated by recent results of Krylov on numerical solutions to the Bellman
equation.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:01:35 GMT"
},
{
"version": "v2",
"created": "Thu, 15 May 2008 06:51:26 GMT"
}
] | 2008-05-15T00:00:00 | [
[
"Gyongy",
"Istvan",
""
],
[
"Siska",
"David",
""
]
] |
0705.2303 | Nobuya Maeshima | Nobuya Maeshima, Kenji Yonemitsu | Charge-Transfer Excitations in One-Dimensional Dimerized Mott Insulators | 6 pages, 6 figures, to be published in J. Phys. Soc. Jpn | null | 10.1143/JPSJ.76.074713 | null | cond-mat.str-el | null | We investigate the optical properties of one-dimensional (1D) dimerized Mott
insulators using the 1D dimerized extended Hubbard model. Numerical
calculations and a perturbative analysis from the decoupled-dimer limit clarify
that there are three relevant classes of charge-transfer (CT) states generated
by photoexcitation: interdimer CT unbound states, interdimer CT exciton states,
and intradimer CT exciton states. This classification is applied to
understanding the optical properties of an organic molecular material,
1,3,5-trithia-2,4,6-triazapentalenyl (TTTA), which is known for its
photoinduced transition from the dimerized spin-singlet phase to the regular
paramagnetic phase. We conclude that the lowest photoexcited state of TTTA is
the interdimer CT exciton state and the second lowest state is the intradimer
CT exciton state.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:04:15 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Maeshima",
"Nobuya",
""
],
[
"Yonemitsu",
"Kenji",
""
]
] |
0705.2304 | Sven Wedemeyer-B\"ohm | S. Wedemeyer-Boehm, H.-G. Ludwig, M. Steffen, J. Leenaarts, and B.
Freytag | Inter-network regions of the Sun at millimetre wavelengths | 15 pages, 10 figures, accepted for publication in A&A (15.05.07) | null | 10.1051/0004-6361:20077588 | null | astro-ph | null | The continuum intensity at wavelengths around 1 mm provides an excellent way
to probe the solar chromosphere. Future high-resolution millimetre arrays, such
as the Atacama Large Millimeter Array (ALMA), will thus produce valuable input
for the ongoing controversy on the thermal structure and the dynamics of this
layer. Synthetic brightness temperature maps are calculated on basis of
three-dimensional radiation (magneto-)hydrodynamic (MHD) simulations. While the
millimetre continuum at 0.3mm originates mainly from the upper photosphere, the
longer wavelengths considered here map the low and middle chromosphere. The
effective formation height increases generally with wavelength and also from
disk-centre towards the solar limb. The average intensity contribution
functions are usually rather broad and in some cases they are even
double-peaked as there are contributions from hot shock waves and cool
post-shock regions in the model chromosphere. Taking into account the
deviations from ionisation equilibrium for hydrogen gives a less strong
variation of the electron density and with it of the optical depth. The result
is a narrower formation height range. The average brightness temperature
increases with wavelength and towards the limb. The relative contrast depends
on wavelength in the same way as the average intensity but decreases towards
the limb. The dependence of the brightness temperature distribution on
wavelength and disk-position can be explained with the differences in formation
height and the variation of temperature fluctuations with height in the model
atmospheres.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:05:27 GMT"
},
{
"version": "v2",
"created": "Fri, 18 May 2007 19:47:50 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wedemeyer-Boehm",
"S.",
""
],
[
"Ludwig",
"H. -G.",
""
],
[
"Steffen",
"M.",
""
],
[
"Leenaarts",
"J.",
""
],
[
"Freytag",
"B.",
""
]
] |
0705.2305 | Tshilidzi Marwala | Sizwe M. Dhlamini, Tshilidzi Marwala, and Thokozani Majozi | Fuzzy and Multilayer Perceptron for Evaluation of HV Bushings | 7 pages | null | null | null | cs.AI cs.NE | null | The work proposes the application of fuzzy set theory (FST) to diagnose the
condition of high voltage bushings. The diagnosis uses dissolved gas analysis
(DGA) data from bushings based on IEC60599 and IEEE C57-104 criteria for oil
impregnated paper (OIP) bushings. FST and neural networks are compared in terms
of accuracy and computational efficiency. Both FST and NN simulations were able
to diagnose the bushings condition with 10% error. By using fuzzy theory, the
maintenance department can classify bushings and know the extent of degradation
in the component.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:06:19 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Dhlamini",
"Sizwe M.",
""
],
[
"Marwala",
"Tshilidzi",
""
],
[
"Majozi",
"Thokozani",
""
]
] |
0705.2306 | Shahar Hod | Shahar Hod | Near-Extreme Black Holes and the Universal Relaxation Bound | 2 Pages. Submitted to PRD on 5/12/2007 | Class.Quant.Grav.24:4235-4238,2007 | 10.1088/0264-9381/24/16/N01 | null | gr-qc astro-ph hep-th | null | A fundamental bound on the relaxation time \tau of a perturbed
thermodynamical system has recently been derived, \tau \geq \hbar/\pi T, where
$T$ is the system's temperature. We demonstrate analytically that black holes
saturate this bound in the extremal limit and for large values of the azimuthal
number m of the perturbation field.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:09:54 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Hod",
"Shahar",
""
]
] |
0705.2307 | Tshilidzi Marwala | Bradley van Aardt, Tshilidzi Marwala | A Study in a Hybrid Centralised-Swarm Agent Community | 6 pages | null | null | null | cs.NE cs.AI | null | This paper describes a systems architecture for a hybrid Centralised/Swarm
based multi-agent system. The issue of local goal assignment for agents is
investigated through the use of a global agent which teaches the agents
responses to given situations. We implement a test problem in the form of a
Pursuit game, where the Multi-Agent system is a set of captor agents. The
agents learn solutions to certain board positions from the global agent if they
are unable to find a solution. The captor agents learn through the use of
multi-layer perceptron neural networks. The global agent is able to solve board
positions through the use of a Genetic Algorithm. The cooperation between
agents and the results of the simulation are discussed here. .
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:12:09 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"van Aardt",
"Bradley",
""
],
[
"Marwala",
"Tshilidzi",
""
]
] |
0705.2308 | Leonardo Campanelli | Leonardo Campanelli | Evolution of Magnetic Fields in Freely Decaying Magnetohydrodynamic
Turbulence | 4 pages, 2 figures; accepted for publication in PRL | Phys.Rev.Lett.98:251302,2007 | 10.1103/PhysRevLett.98.251302 | null | astro-ph | null | We study the evolution of magnetic fields in freely decaying
magnetohydrodynamic turbulence. By quasi-linearizing the Navier-Stokes
equation, we solve analytically the induction equation in quasi-normal
approximation. We find that, if the magnetic field is not helical, the magnetic
energy and correlation length evolve in time respectively as E_B \propto
t^{-2(1+p)/(3+p)} and \xi_B \propto t^{2/(3+p)}, where p is the index of
initial power-law spectrum. In the helical case, the magnetic helicity is an
almost conserved quantity and forces the magnetic energy and correlation length
to scale as E_B \propto (log t)^{1/3} t^{-2/3} and \xi_B \propto (log t)^{-1/3}
t^{2/3}.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:13:45 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Campanelli",
"Leonardo",
""
]
] |
0705.2309 | L\^e Tu\^an Hoa | L\^e Tu\^an Hoa | Stability of associated primes of monomial ideals | null | Vietnam J. Math. 34(2006), No.4 | null | null | math.AC math.AG | null | Let $I$ be a monomial ideal of a polynomial ring $R$. In this paper we
determine a number $B$ such that $\Ass (I^n/I^{n+1}) = \Ass (I^{B}/I^{B+1})$
for all $n\geq B$.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:15:37 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hoa",
"Lê Tuân",
""
]
] |
0705.2310 | Tshilidzi Marwala | C.B. Vilakazi, T. Marwala, P. Mautla and E. Moloto | On-Line Condition Monitoring using Computational Intelligence | 8 pages | null | null | null | cs.AI | null | This paper presents bushing condition monitoring frameworks that use
multi-layer perceptrons (MLP), radial basis functions (RBF) and support vector
machines (SVM) classifiers. The first level of the framework determines if the
bushing is faulty or not while the second level determines the type of fault.
The diagnostic gases in the bushings are analyzed using the dissolve gas
analysis. MLP gives superior performance in terms of accuracy and training time
than SVM and RBF. In addition, an on-line bushing condition monitoring
approach, which is able to adapt to newly acquired data are introduced. This
approach is able to accommodate new classes that are introduced by incoming
data and is implemented using an incremental learning algorithm that uses MLP.
The testing results improved from 67.5% to 95.8% as new data were introduced
and the testing results improved from 60% to 95.3% as new conditions were
introduced. On average the confidence value of the framework on its decision
was 0.92.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:19:00 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Vilakazi",
"C. B.",
""
],
[
"Marwala",
"T.",
""
],
[
"Mautla",
"P.",
""
],
[
"Moloto",
"E.",
""
]
] |
0705.2311 | Sergey Golovin | Sergey V. Golovin | Multidimensional fluid motions with planar waves | 21 pages, 13 figures | Journal of Applied Mechanics and Technical Physics, 2008, Volume
49, Number 5, Pages 725-736 | 10.1007/s10808-008-0091-6 | null | physics.flu-dyn | null | In the classical one-dimensional solution of fluid dynamics equations all
unknown functions depend only on time t and Cartesian coordinate x. Although
fluid spreads in all directions (velocity vector has three components) the
whole picture of motion is relatively simple: trajectory of one fluid particle
from plane x=const completely determines motion of the whole plane. Basing on
the symmetry analysis of differential equations we propose generalization of
this solution allowing movements in different directions of fluid particles
belonging to plane x=const. At that, all functions but an angle determining the
direction of particle's motion depend on t and x only, whereas the angle
depends on all coordinates. In this solution the whole picture of motion
superposes from identical trajectories placed under different angles in 3D
space. Orientations of the trajectories are restricted by a finite relation
possessing functional arbitrariness. The solution describes three-dimensional
nonlinear processes and singularities in infinitely conducting plasma, gas or
incompressible liquid.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:18:38 GMT"
}
] | 2010-08-05T00:00:00 | [
[
"Golovin",
"Sergey V.",
""
]
] |
0705.2312 | Jingbo Wang | C. Hines, K. Jacobs, J.B. Wang | Readout of solid-state charge qubits using a single-electron pump | 5 pages, revtex4, 4 eps figures. v2: published version | J. Phys. A: Math. Theor. 40, F609 (2007) | 10.1088/1751-8113/40/27/F05 | null | quant-ph | null | A major difficulty in realizing a solid-state quantum computer is the
reliable measurement of the states of the quantum registers. In this paper, we
propose an efficient readout scheme making use of the resonant tunneling of a
ballistic electron produced by a single electron pump. We treat the measurement
interaction in detail by modeling the full spatial configuration, and show that
for pumped electrons with suitably chosen energy the transmission coefficient
is very sensitive to the qubit state. We further show that by using a short
sequence of pumping events, coupled with a simple feedback control procedure,
the qubit can be measured with high accuracy.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:39:03 GMT"
},
{
"version": "v2",
"created": "Thu, 21 Jun 2007 16:53:33 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Hines",
"C.",
""
],
[
"Jacobs",
"K.",
""
],
[
"Wang",
"J. B.",
""
]
] |
0705.2313 | Olivier Powell | Olivier Powell, Luminita Moraru, Jean-Marc Seigneur | TrustMIX: Trustworthy MIX for Energy Saving in Sensor Networks | 19 pages, 7 figures | null | null | null | cs.DC cs.CR cs.NI | null | MIX has recently been proposed as a new sensor scheme with better energy
management for data-gathering in Wireless Sensor Networks. However, it is not
known how it performs when some of the sensors carry out sinkhole attacks. In
this paper, we propose a variant of MIX with adjunct computational trust
management to limit the impact of such sinkhole attacks. We evaluate how MIX
resists sinkhole attacks with and without computational trust management. The
main result of this paper is to find that MIX is very vulnerable to sinkhole
attacks but that the adjunct trust management efficiently reduces the impact of
such attacks while preserving the main feature of MIX: increased lifetime of
the network.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:22:21 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Powell",
"Olivier",
""
],
[
"Moraru",
"Luminita",
""
],
[
"Seigneur",
"Jean-Marc",
""
]
] |
0705.2314 | Alan D. Martin | V.A. Khoze, A.D. Martin and M.G. Ryskin | New Physics with Tagged Forward Protons at the LHC | 12 pages, 4 figures, presented by V.A. Khoze at the 21st Workshop Les
Rencontres de Physique de la Vallee d'Aoste, La Thuile, 4-10 March, 2007 | Frascati Phys.Ser.44:147-160,2007 | null | IPPP/07/21, DCPT/07/42 | hep-ph | null | The addition of forward proton detectors to LHC experiments will
significantly enlarge the potential for studying New Physics. A topical example
is Higgs production by the central exclusive diffractive process, pp -> p+H+p.
We discuss the exclusive production of Higgs bosons in both the SM and MSSM.
Special attention is paid to the backgrounds to the H -> bbbar signal.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:27:23 GMT"
}
] | 2011-04-11T00:00:00 | [
[
"Khoze",
"V. A.",
""
],
[
"Martin",
"A. D.",
""
],
[
"Ryskin",
"M. G.",
""
]
] |
0705.2315 | Lars Mattsson | Lars Mattsson, Susanne Hoefner, Rurik Wahlin and Falk Herwig | On the Connection between Mass Loss and Evolution of C-rich AGB stars | 5 pages, 2 figures. To be published in the proceedings of the
conference "Why Galaxies Care about AGB Stars", held in Vienna, August 7-11,
2006; F. Kerschbaum, C. Charbonnel, B. Wing eds, ASP Conf.Ser. in press.
Replaced to match published version. Reference list corrected | null | null | null | astro-ph | null | The mass loss properties of carbon AGB stars are not very well constrained at
present. A variety of empirical or theoretical formulae with different
parameterisations are available in the literature and the agreement between
them is anything but good. These simple mass loss prescriptions are nontheless
used in many models of stellar evolution without much consideration of their
applicability in various cases. We present here an on-going project aiming at a
better description of the mass loss, that could be used to improve stellar
evolution models -- especially the evolution during the TP-AGB phase. As a
first step, we have considered the mass loss evolution during a He-shell flash.
Using stellar parameters sampled from a stellar evolutionary track, we have
computed the time evolution of the atmospheric layers and wind acceleration
region during a flash event with detailed frequency-dependent
radiation-hydrodynamical models including dust formation. Based on these
results, we have also simulated the subsequent long-term dynamical evolution of
the circumstellar envelope (CSE), including the formation of a detached shell.
We find that existing simple mass loss prescriptions imply different mass loss
evolutions compared with our model. The second step of the project deals with
the dependence of mass loss on the basic stellar parameters. At the moment we
are computing a large grid of wind models for C-rich AGB stars. Preliminary
results show that simple parameterisations are difficult to obtain in certain
regions of the parameter space considered, due to strong non-linearities in the
wind mechanism.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:43:19 GMT"
},
{
"version": "v2",
"created": "Wed, 13 Jun 2007 14:55:04 GMT"
}
] | 2019-08-19T00:00:00 | [
[
"Mattsson",
"Lars",
""
],
[
"Hoefner",
"Susanne",
""
],
[
"Wahlin",
"Rurik",
""
],
[
"Herwig",
"Falk",
""
]
] |
0705.2316 | Zaza Osmanov | N. Chkheidze, D. Lomiashvili | On The Recently Discovered Pulsations From RX J1856.5-3754 | 7 pages, 2 figures | null | 10.1016/j.newast.2007.06.007 | null | astro-ph | null | An explanation of the recently discovered 7 s pulsations from the isolated
neutron star RX J1856.5-3754 is presented. It is assumed that the real spin
period of this source is $\approx1$ s, whereas the observed spin-modulation is
caused by the presence of a nearly transverse, very low frequency drift waves
in the pulsar magnetosphere. It is supposed that the period of the drift wave
is equal to a recently observed one. The simulated lightcurve is plotted, the
angular parameters are defined and the value of the pulsed fraction of only
$\sim 1.2%$ is explained.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:54:15 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Chkheidze",
"N.",
""
],
[
"Lomiashvili",
"D.",
""
]
] |
0705.2317 | Giuseppe Bimonte | Giuseppe Bimonte | Johnson noise and the thermal Casimir effect | 10 pages, 1 encapsulated figure. Version accepted for publication in
New Journal of Physics | New J.Phys.9:281,2007 | 10.1088/1367-2630/9/8/281 | DSF 18/2007 | quant-ph | null | We study the thermal interaction between two nearby thin metallic wires, at
finite temperature. It is shown that the Johnson currents in the wires give
rise, via inductive coupling, to a repulsive force between them. This thermal
interaction exhibits all the puzzling features found recently in the thermal
Casimir effect for lossy metallic plates, suggesting that the physical origin
of the difficulties encountered in the Casimir problem resides in the inductive
coupling between the Johnson currents inside the plates. We show that in our
simple model all puzzles are resolved if account is taken of capacitive effects
associated with the end points of the wires. Our findings suggest that
capacitive finite-size effects may play an important role in the resolution of
the analogous problems met in the thermal Casimir effect.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:58:08 GMT"
},
{
"version": "v2",
"created": "Fri, 18 May 2007 10:29:31 GMT"
},
{
"version": "v3",
"created": "Thu, 26 Jul 2007 12:44:46 GMT"
}
] | 2011-07-19T00:00:00 | [
[
"Bimonte",
"Giuseppe",
""
]
] |
0705.2318 | Seiji Miyoshi | Hideto Utsumi, Seiji Miyoshi, Masato Okada | Statistical Mechanics of Nonlinear On-line Learning for Ensemble
Teachers | 13 pages, 9 figures | null | 10.1143/JPSJ.76.114001 | null | cs.LG cond-mat.dis-nn | null | We analyze the generalization performance of a student in a model composed of
nonlinear perceptrons: a true teacher, ensemble teachers, and the student. We
calculate the generalization error of the student analytically or numerically
using statistical mechanics in the framework of on-line learning. We treat two
well-known learning rules: Hebbian learning and perceptron learning. As a
result, it is proven that the nonlinear model shows qualitatively different
behaviors from the linear model. Moreover, it is clarified that Hebbian
learning and perceptron learning show qualitatively different behaviors from
each other. In Hebbian learning, we can analytically obtain the solutions. In
this case, the generalization error monotonically decreases. The steady value
of the generalization error is independent of the learning rate. The larger the
number of teachers is and the more variety the ensemble teachers have, the
smaller the generalization error is. In perceptron learning, we have to
numerically obtain the solutions. In this case, the dynamical behaviors of the
generalization error are non-monotonic. The smaller the learning rate is, the
larger the number of teachers is; and the more variety the ensemble teachers
have, the smaller the minimum value of the generalization error is.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 09:58:39 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Utsumi",
"Hideto",
""
],
[
"Miyoshi",
"Seiji",
""
],
[
"Okada",
"Masato",
""
]
] |
0705.2319 | Aranya Bhattacherjee Dr. | Aranya B Bhattacherjee | Coherence Properties of a Bose-Einstein Condensate in an Optical
Superlattice | 12 pages, 5 figures | European Physical Journal. D, (2007) | 10.1140/epjd/e2007-00309-0 | null | cond-mat.stat-mech | null | We study the effect of a one dimensional optical superlattice on the
superfluid fraction, number squeezing, dynamic structure factor and the
quasi-momentum distribution of the Mott-insulator. We show that due to the
secondary lattice,there is a decrease in the superfluid fraction and the number
fluctuation. The dynamic structure factor which can be measured by Bragg
spectroscopy is also suppressed due to the addition of the secondary lattice.
The visibility of the interference pattern (the quasi-momentum distribution)of
the Mott-insulator is found to decrease due to the presence of the secondary
lattice. Our results have important implications in atom interferometry and
quantum computation in optical lattices.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 10:03:45 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Jul 2007 16:36:25 GMT"
}
] | 2007-11-22T00:00:00 | [
[
"Bhattacherjee",
"Aranya B",
""
]
] |
0705.2320 | Alexander Iomin | Alexander Iomin and Shmuel Fishman | The Localization Length of Stationary States in the Nonlinear
Schreodinger Equation | null | Phys.Rev.E76:056607,2007 | 10.1103/PhysRevE.76.056607 | null | cond-mat.dis-nn astro-ph nlin.CD | null | For the nonlinear Schreodinger equation (NLSE), in presence of disorder,
exponentially localized stationary states are found. In the present Letter it
is demonstrated analytically that the localization length is typically
independent of the strength of the nonlinearity and is identical to the one
found for the corresponding linear equation. The analysis makes use of the
correspondence between the stationary NLSE and the Langevin equation as well as
of the resulting Fokker-Planck equation. The calculations are performed for the
``white noise'' random potential and an exact expression for the exponential
growth of the eigenstates is obtained analytically. It is argued that the main
conclusions are robust.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:13:51 GMT"
},
{
"version": "v2",
"created": "Sun, 16 Sep 2007 10:38:35 GMT"
}
] | 2010-02-15T00:00:00 | [
[
"Iomin",
"Alexander",
""
],
[
"Fishman",
"Shmuel",
""
]
] |
0705.2321 | Qingyang Guan | Qingyang Guan | Cadlag curves of SLE driven by Levy processes | 18 page, corrections | null | null | null | math.PR math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Schramm Loewner Evolutions (SLE) are random increasing hulls defined through
the Loewner equation driven by Brownian motion. It is known that the increasing
hulls are generated by continuous curves. When the driving process is of the
form \sqrt{\kappa} B+\theta^{1/\alpha}S for a Brownian motion B and a symmetric
\alpha-stable process S with \kappa not equal to 4 and 8, we prove that the
corresponding increasing hulls are generated by Cadlag curves.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 10:11:58 GMT"
},
{
"version": "v2",
"created": "Fri, 5 Sep 2008 10:10:12 GMT"
}
] | 2008-09-05T00:00:00 | [
[
"Guan",
"Qingyang",
""
]
] |
0705.2322 | Mikito Koshino | Mikito Koshino and Tsuneya Ando | Diamagnetism in disordered graphene | 8 pages, 4 figures, to appear in Physical Review B | null | 10.1103/PhysRevB.75.235333 | null | cond-mat.mes-hall | null | The orbital magnetism is studied in graphene monolayer within the effective
mass approximation. In models of short-range and long-range disorder, the
magnetization is calculated with self-consistent Born approximation. In the
zero-field limit, the susceptibility becomes highly diamagnetic around zero
energy, while it has a long tail proportional to the inverse of the Fermi
energy. We demonstrated how the magnetic oscillation vanishes and converges to
the susceptibility, on going from a strong-field regime to zero-field. The
behavior at zero energy is shown to be highly singular.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 10:57:04 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Koshino",
"Mikito",
""
],
[
"Ando",
"Tsuneya",
""
]
] |
0705.2323 | Peter Bantay | P. Bantay | The orbifold transform and its applications | null | null | 10.1007/s11005-007-0216-5 | null | math.GR math.CO | null | We discuss the notion of the orbifold transform, and illustrate it on simple
examples. The basic properties of the transform are presented, including
transitivity and the exponential formula for symmetric products. The connection
with the theory of permutation orbifolds is addressed, and the general results
illustrated on the example of torus partition functions.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 10:33:15 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bantay",
"P.",
""
]
] |
0705.2324 | Bimalendu Deb | Bimalendu Deb | Finite temperature effects in light scattering off Cooper-paired Fermi
atoms | 18 pages, 4 figures, Accepted in J. Phys. B: At. Mol. & Opt. Phys | J. Phys. B: At. Mol. & Opt. Phys., Vol.40, p.2399-2415 (2007) | 10.1088/0953-4075/40/12/015 | null | cond-mat.other cond-mat.supr-con | null | We study stimulated light scattering off a superfluid Fermi gas of atoms at
finite temperature. We derive response function that takes into account vertex
correction due to final state interactions; and analyze finite temperature
effects on collective and quasiparticle excitations of a uniform superfluid
Fermi gas. Light polarization is shown to play an important role in
excitations. Our results suggest that it is possible to excite
Bogoliubov-Anderson phonon at a large scattering length by light scattering.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 10:46:46 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Deb",
"Bimalendu",
""
]
] |
0705.2325 | Orfeu Bertolami | Orfeu Bertolami | A Curvature Principle for the interaction between universes | Essay selected for an honorable mention by the Gravity Research
Foundation, 2007. Plain latex, 8 pages | Gen.Rel.Grav.40:1891-1898,2008 | 10.1007/s10714-008-0608-6 | DF/IST-2.2007 | gr-qc | null | We propose a Curvature Principle to describe the dynamics of interacting
universes in a multi-universe scenario and show, in the context of a simplified
model, how interaction drives the cosmological constant of one of the universes
toward a vanishingly small value. We also conjecture on how the proposed
Curvature Principle suggests a solution for the entropy paradox of a universe
where the cosmological constant vanishes.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 10:49:57 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bertolami",
"Orfeu",
""
]
] |
0705.2326 | Federico Alberto Ceccopieri | Federico A. Ceccopieri (Univ. di Parma) and Luca Trentadue (INFN
Parma) | A New Fracture Function Approach to QCD Initial State Radiation | 10 pages, 5 figures, revtex4 | Phys.Lett.B655:15-25,2007 | 10.1016/j.physletb.2007.07.074 | null | hep-ph | null | Ordinary fracture functions, describing hadrons production in the deep
inelastic scattering target fragmentation region, are generalized to account
for the production of hadrons in arbitrary number, thus offering a renewed
framework for dealing with QCD initial state radiation. We also propose a new
jet-like observable which measures beam remnants and low-$p_{\perp}$ scattering
fragments and derive its QCD evolution equations by using Jet Calculus.
Possible implications for semi-inclusive deep inelastic scattering and
hadron-hadron reactions are shortly discussed.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 10:59:59 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Ceccopieri",
"Federico A.",
"",
"Univ. di Parma"
],
[
"Trentadue",
"Luca",
"",
"INFN\n Parma"
]
] |
0705.2327 | Jos Zwanikken | Jos Zwanikken, and Ren\'e van Roij | Destructed double-layer and ionic charge separation near the oil-water
interface | 4 pages, 2 figures (figure 1a, 1b, 2) | null | null | null | cond-mat.soft | null | We study suspensions of hydrophobic charged colloidal spheres dispersed in a
demixed oil-water mixture by means of a modified Poisson-Boltzmann theory,
taking into account image charge effects and partitioning of the monovalent
ions. We find that the ion's aversion for oil can destroy the double layers of
the oil-dispersed colloids. This affects the salt-concentration dependence of
the colloidal adsorption to the oil-water interface qualitatively. The theory
also predicts a narrow range of the oil-dielectric constant in which
micron-sized water-in-oil droplets acquire enough charge to crystallize at
volume fractions as small as $\sim 10^{-3}$ in the absence of colloids. These
findings explain recent observations [M.E. Leunissen {\em et al.}, Proc. Nat.
Ac. Sci {\bf 104}, 2585 (2007)].
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:08:24 GMT"
}
] | 2016-08-14T00:00:00 | [
[
"Zwanikken",
"Jos",
""
],
[
"van Roij",
"René",
""
]
] |
0705.2328 | Cosmo Lupo | Cosmo Lupo | On the realignment criterion and beyond | This paper has been withdrawn by the author, its content is now
available as part of arXiv:0802.2019 | null | null | null | quant-ph | null | The content of this paper is now available as part of arXiv:0802.2019
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:11:34 GMT"
},
{
"version": "v2",
"created": "Fri, 15 Feb 2008 10:32:15 GMT"
}
] | 2008-02-15T00:00:00 | [
[
"Lupo",
"Cosmo",
""
]
] |
0705.2329 | Mark Owen | Mark Owen | Search for Neutral Higgs Boson Production in the Decay h to tau(mu) tau
with the D0 Detector | On behalf of the DZero collaboration, Contribution to the Proceedings
of the XLIInd Rencontres de Moriond, Electroweak Interactions and Unified
Theories | null | null | MAN/HEP/2007/9 FERMILAB-CONF-07-084-E | hep-ex | null | A search for the production of neutral Higgs bosons decaying into tau tau
final states is presented. One of the two tau leptons is required to decay into
a muon. The data were collected by the D0 detector and correspond to an
integrated luminosity of about 1.0 fb-1. No excess is observed above the
expected backgrounds. The results are interpreted in the Minimal Supersymmetric
Standard Model. In the mass range 90<mA<200 GeV values of tan(beta) larger than
40-60 are excluded for the no-mixing and the mhmax benchmark scenarios.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:50:58 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Owen",
"Mark",
""
]
] |
0705.2330 | Sofia Randich | S. Randich, F. Primas, L. Pasquini, P. Sestito, and R. Pallavicini | Tracing mixing in stars: new beryllium observations of the open clusters
NGC 2516, Hyades, and M67 | 19 pages, 10 figures, accepted for publication in Astronomy &
Astrophysics | null | 10.1051/0004-6361:20066218 | null | astro-ph | null | Determinations of beryllium abundance in stars, together with lithium,
provide a key tool to investigate the so far poorly understood extra-mixing
processes at work in stellar interiors. We measured Be in three open
clusters,complementing existing Be surveys, and aiming at gathering a more
complete empirical scenario of the evolution of Be as a function of stellar age
and temperature. Specifically, we analyzed VLT/UVES spectra of members of NGC
2516, the Hyades, and M 67 to determine their Be and Li abundances. In the
first two clusters we focused on stars cooler than 5400 K, while the M 67
sample includes stars warmer than 6150 K, as well as two subgiants and two blue
stragglers. We also computed the evolution of Be for a 0.9 Mo star based on
standard evolutionary models. We find different emprical behaviours for stars
in different temperature bins and ages. Stars warmer than 6150 K show Be
depletion and follow a Be vs. Li correlation while Be is undepleted in stars in
the ~6150-5600 K range. NGC 2516 members cooler than 5400 K have not depleted
any Be, but older Hyades of similar temperature do show some depletion. Be is
severely depleted in the subgiants and blue stragglers. The results for warm
stars are in agreement with previous studies, supporting the hypothesis that
mixing in this temperature regime is driven by rotation. The same holds for the
two subgiants that have evolved from the "Li gap". This mechanism is instead
not the dominant one for solar-type stars. We show that Be depletion of cool
Hyades cannot simply be explained by the effect of increasing depth of the
convective zone. Finally, the different Be content of the two blue stragglers
suggests that they have formed by two different processes (i.e., collisions vs.
binary merging).
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:32:53 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Randich",
"S.",
""
],
[
"Primas",
"F.",
""
],
[
"Pasquini",
"L.",
""
],
[
"Sestito",
"P.",
""
],
[
"Pallavicini",
"R.",
""
]
] |
0705.2331 | Valeria L. Gili | Mauro Carfora, Claudio Dappiaggi, Valeria L. Gili | Boundary Conformal Field Theory and Ribbon Graphs: a tool for
open/closed string dualities | 40 pages, 7 figures; typos corrected | JHEP0707:021,2007 | 10.1088/1126-6708/2007/07/021 | FNT/T 2007/03, QMUL-PH-07-12 | hep-th | null | We construct and fully characterize a scalar boundary conformal field theory
on a triangulated Riemann surface. The results are analyzed from a string
theory perspective as tools to deal with open/closed string dualities.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:35:51 GMT"
},
{
"version": "v2",
"created": "Fri, 27 Jul 2007 10:07:21 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Carfora",
"Mauro",
""
],
[
"Dappiaggi",
"Claudio",
""
],
[
"Gili",
"Valeria L.",
""
]
] |
0705.2332 | Dan Roozemond | Jos in 't panhuis, Erik Postma, Dan Roozemond | Extremal Presentations for Classical Lie Algebras | 26 pages, 6 figures | null | 10.1016/j.jalgebra.2009.04.015 | null | math.RA | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The long-root elements in Lie algebras of Chevalley type have been well
studied and can be characterized as extremal elements, that is, elements $x$
such that the image of $(\ad x)^2$ lies in the subspace spanned by $x$. In this
paper, assuming an algebraically closed base field of characteristic not 2, we
find presentations of the Lie algebras of classical Chevalley type by means of
minimal sets of extremal generators. The relations are described by simple
graphs on the sets. For example, for $C_n$ the graph is a path of length $2n$,
and for $A_n$ the graph is the triangle connected to a path of length $n-3$.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:44:20 GMT"
},
{
"version": "v2",
"created": "Thu, 7 Jun 2007 14:30:00 GMT"
},
{
"version": "v3",
"created": "Fri, 24 Aug 2007 08:00:46 GMT"
},
{
"version": "v4",
"created": "Fri, 6 Mar 2009 09:56:49 GMT"
}
] | 2011-06-17T00:00:00 | [
[
"panhuis",
"Jos in 't",
""
],
[
"Postma",
"Erik",
""
],
[
"Roozemond",
"Dan",
""
]
] |
0705.2333 | Anatoly D. Erlykin | A.D.Erlykin, A.W.Wolfendale | Gamma Rays frim the Galactic Centre | 21 pages, 7 figures, accepted by J. Phys. G: Nucl. Part. Phys | J.Phys.G34:1813-1826,2007 | 10.1088/0954-3899/34/7/019 | null | astro-ph | null | Recent results from the HESS gamma ray telescope have shown the presence of
both a diffuse, extended, flux of gamma rays above ~0.4 TeV and discrete
sources in and near the Galactic Centre. Here, we put forward a possible
explanation in terms of the diffusion of cosmic ray protons from a succession
of supernova remnants (SNR) in the SgrA* region of the Galaxy plus a
contribution from SNR in the rest of the Galactic Centre Region, to be called
the Galactic Centre Ridge (GCR). Protons are favoured over electrons because
the mG magnetic fields in the Region will attenuate energetic electrons
severely. Prominent features are the need for 'anomalous diffusion' of the
protons in the whole region and the adoption of low efficiency for SNR
acceleration in the high density regions. The latter is related by us to the
well-known low 'cosmic ray gradient' in the Galaxy. A corroborating feature is
the close correlation of inferred cosmic ray intensity with the smoothed
intensity of 5 GHZ radio radiation. We attribute this to the presence of the
SNR in the GCR.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:45:10 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Erlykin",
"A. D.",
""
],
[
"Wolfendale",
"A. W.",
""
]
] |
0705.2334 | Charles Doiron | C. B. Doiron, B. Trauzettel and C. Bruder | Improved position measurement of nano electromechanical systems using
cross correlations | 9 pages, 1 figure; v2: new Sec. V | Phys. Rev. B 76, 195312 (2007) | 10.1103/PhysRevB.76.195312 | null | cond-mat.mes-hall | null | We consider position measurements using the cross-correlated output of two
tunnel junction position detectors. Using a fully quantum treatment, we
calculate the equation of motion for the density matrix of the coupled
detector-detector-mechanical oscillator system. After discussing the presence
of a bound on the peak-to-background ratio in a position measurement using a
single detector, we show how one can use detector cross correlations to
overcome this bound. We analyze two different possible experimental
realizations of the cross correlation measurement and show that in both cases
the maximum cross-correlated output is obtained when using twin detectors and
applying equal bias to each tunnel junction. Furthermore, we show how the
double-detector setup can be exploited to drastically reduce the added
displacement noise of the oscillator.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 11:59:08 GMT"
},
{
"version": "v2",
"created": "Wed, 31 Oct 2007 10:24:33 GMT"
}
] | 2007-11-27T00:00:00 | [
[
"Doiron",
"C. B.",
""
],
[
"Trauzettel",
"B.",
""
],
[
"Bruder",
"C.",
""
]
] |
0705.2335 | Christian Sturm | Johann H. Kuhn, Matthias Steinhauser and Christian Sturm | Precise Charm and Bottom quark masses | 4 pages, 2 figures, talk given by Johann H. Kuhn at 42nd Rencontres
de Moriond on QCD and High-Energy Hadronic Interactions, La Thuile, March
2007 | null | null | TTP07-09 | hep-ph | null | New data for the total cross section sigma(e^+e^- --> hadrons) in the charm
and bottom threshold region are combined with an improved theoretical analysis,
which includes recent four-loop calculations, to determine the short distance
\bar{MS} charm and bottom quark masses. The final result for the
\bar{MS}-masses, m_c(3 GeV)=0.986(13) GeV and m_b(10 GeV)=3.609(25) GeV is
consistent with but significantly more precise than a similar previous study.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 12:17:03 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kuhn",
"Johann H.",
""
],
[
"Steinhauser",
"Matthias",
""
],
[
"Sturm",
"Christian",
""
]
] |
0705.2336 | Klaus Kirch | G. Ban, K. Bodek, M. Daum, R. Henneck, S. Heule, M. Kasprzak, N.
Khomutov, K. Kirch, S. Kistryn, A. Knecht, P. Knowles, M. Kuzniak, T. Lefort,
A. Mtchedlishvili, O. Naviliat-Cuncic, C. Plonka, G. Quemener, M. Rebetez, D.
Rebreyend, S. Roccia, G. Rogel, M. Tur, A. Weis, J. Zejma, G. Zsigmond | A direct experimental limit on neutron -- mirror neutron oscillations | 4 pages, 1 figure. accepted for publication in Phys. Rev. Lett | Phys.Rev.Lett.99:161603,2007 | 10.1103/PhysRevLett.99.161603 | null | nucl-ex | null | In case a mirror world with a copy of our ordinary particle spectrum would
exist, the neutron n and its degenerate partner, the mirror neutron ${\rm n'}$,
could potentially mix and undergo ${\rm nn'}$ oscillations. The interaction of
an ordinary magnetic field with the ordinary neutron would lift the degeneracy
between the mirror partners, diminish the ${\rm n'}$-amplitude in the
n-wavefunction and, thus, suppress its observability. We report an experimental
comparison of ultracold neutron storage in a trap with and without superimposed
magnetic field. No influence of the magnetic field is found and, assuming
negligible mirror magnetic fields, a limit on the oscillation time $\tau_{\rm
nn'} > 103$ s (95% C.L.) is derived.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 12:00:26 GMT"
},
{
"version": "v2",
"created": "Thu, 13 Sep 2007 10:12:05 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Ban",
"G.",
""
],
[
"Bodek",
"K.",
""
],
[
"Daum",
"M.",
""
],
[
"Henneck",
"R.",
""
],
[
"Heule",
"S.",
""
],
[
"Kasprzak",
"M.",
""
],
[
"Khomutov",
"N.",
""
],
[
"Kirch",
"K.",
""
],
[
"Kistryn",
"S.",
""
],
[
"Knecht",
"A.",
""
],
[
"Knowles",
"P.",
""
],
[
"Kuzniak",
"M.",
""
],
[
"Lefort",
"T.",
""
],
[
"Mtchedlishvili",
"A.",
""
],
[
"Naviliat-Cuncic",
"O.",
""
],
[
"Plonka",
"C.",
""
],
[
"Quemener",
"G.",
""
],
[
"Rebetez",
"M.",
""
],
[
"Rebreyend",
"D.",
""
],
[
"Roccia",
"S.",
""
],
[
"Rogel",
"G.",
""
],
[
"Tur",
"M.",
""
],
[
"Weis",
"A.",
""
],
[
"Zejma",
"J.",
""
],
[
"Zsigmond",
"G.",
""
]
] |
0705.2337 | Piet Brouwer | Piet W. Brouwer and Saar Rahav | Universal parametric correlations in the classical limit of quantum
transport | 4 pages, 2 figures | Phys. Rev. B 75, 201303 (2007) | 10.1103/PhysRevB.75.201303 | null | cond-mat.mes-hall | null | Quantum corrections to transport through a chaotic ballistic cavity are known
to be universal. The universality not only applies to the magnitude of quantum
corrections, but also to their dependence on external parameters, such as the
Fermi energy or an applied magnetic field. Here we consider such parameter
dependence of quantum transport in a ballistic chaotic cavity in the
semiclassical limit obtained by sending Planck's constant to zero without
changing the classical dynamics of the open cavity. In this limit quantum
corrections are shown to have a universal parametric dependence which is not
described by random matrix theory.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 12:02:43 GMT"
}
] | 2007-08-22T00:00:00 | [
[
"Brouwer",
"Piet W.",
""
],
[
"Rahav",
"Saar",
""
]
] |
0705.2338 | Shu-Yu Hsu | Shu-Yu Hsu | An elementary proof of the convergence of Ricci flow on compact surfaces | This paper has been withdrawn | null | null | null | math.DG math.AP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This paper has been withdrawn by the author for further modification.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 12:08:41 GMT"
},
{
"version": "v2",
"created": "Wed, 3 Jun 2009 06:40:01 GMT"
}
] | 2009-06-03T00:00:00 | [
[
"Hsu",
"Shu-Yu",
""
]
] |
0705.2339 | Daniele Bettinelli | Daniele Bettinelli, Ruggero Ferrari, Andrea Quadri | A Massive Yang-Mills Theory based on the Nonlinearly Realized Gauge
Group | 44 pages, 1 figure, minor changes, final version accepted by Phys.
Rev. D | Phys.Rev.D77:045021,2008 | 10.1103/PhysRevD.77.045021 | IFUM-893-FT | hep-th hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a subtraction scheme for a massive Yang-Mills theory realized via
a nonlinear representation of the gauge group (here SU(2)). It is based on the
subtraction of the poles in D-4 of the amplitudes, in dimensional
regularization, after a suitable normalization has been performed. Perturbation
theory is in the number of loops and the procedure is stable under iterative
subtraction of the poles. The unphysical Goldstone bosons, the Faddeev-Popov
ghosts and the unphysical mode of the gauge field are expected to cancel out in
the unitarity equation. The spontaneous symmetry breaking parameter is not a
physical variable. We use the tools already tested in the nonlinear sigma
model: hierarchy in the number of Goldstone boson legs and weak power-counting
property (finite number of independent divergent amplitudes at each order). It
is intriguing that the model is naturally based on the symmetry SU(2)_L local
times SU(2)_R global. By construction the physical amplitudes depend on the
mass and on the self-coupling constant of the gauge particle and moreover on
the scale parameter of the radiative corrections. The Feynman rules are in the
Landau gauge.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:04:49 GMT"
},
{
"version": "v2",
"created": "Wed, 5 Sep 2007 07:13:32 GMT"
},
{
"version": "v3",
"created": "Mon, 16 Jun 2008 07:22:23 GMT"
}
] | 2008-06-16T00:00:00 | [
[
"Bettinelli",
"Daniele",
""
],
[
"Ferrari",
"Ruggero",
""
],
[
"Quadri",
"Andrea",
""
]
] |
0705.2340 | Peter Boyle | David J. Antonio, Kenneth C. Bowler, Peter A. Boyle, Norman H. Christ,
Michael A. Clark, Saul D. Cohen, Chris Dawson, Alistair Hart, Balint Jo\'o,
Chulwoo Jung, Richard D. Kenway, Shu Li, Meifeng Lin, Robert D. Mawhinney,
Christopher M. Maynard, Shigemi Ohta, Robert J. Tweedie, Azusa Yamaguchi | Localization and chiral symmetry in 2+1 flavor domain wall QCD | 59 Pages, 23 figures, 1 MPG linked | Phys.Rev.D77:014509,2008 | 10.1103/PhysRevD.77.014509 | CU-TP-1160, Edinburgh 2007/3, RBRC-649, KEK-TH-1138 | hep-lat | null | We present results for the dependence of the residual mass of domain wall
fermions (DWF) on the size of the fifth dimension and its relation to the
density and localization properties of low-lying eigenvectors of the
corresponding hermitian Wilson Dirac operator relevant to simulations of 2+1
flavor domain wall QCD. Using the DBW2 and Iwasaki gauge actions, we generate
ensembles of configurations with a $16^3\times 32$ space-time volume and an
extent of 8 in the fifth dimension for the sea quarks. We demonstrate the
existence of a regime where the degree of locality, the size of chiral symmetry
breaking and the rate of topology change can be acceptable for inverse lattice
spacings $a^{-1} \ge 1.6$ GeV.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:28:13 GMT"
},
{
"version": "v2",
"created": "Fri, 18 May 2007 14:33:21 GMT"
},
{
"version": "v3",
"created": "Wed, 23 May 2007 10:58:16 GMT"
},
{
"version": "v4",
"created": "Wed, 7 Nov 2007 13:20:57 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Antonio",
"David J.",
""
],
[
"Bowler",
"Kenneth C.",
""
],
[
"Boyle",
"Peter A.",
""
],
[
"Christ",
"Norman H.",
""
],
[
"Clark",
"Michael A.",
""
],
[
"Cohen",
"Saul D.",
""
],
[
"Dawson",
"Chris",
""
],
[
"Hart",
"Alistair",
""
],
[
"Joó",
"Balint",
""
],
[
"Jung",
"Chulwoo",
""
],
[
"Kenway",
"Richard D.",
""
],
[
"Li",
"Shu",
""
],
[
"Lin",
"Meifeng",
""
],
[
"Mawhinney",
"Robert D.",
""
],
[
"Maynard",
"Christopher M.",
""
],
[
"Ohta",
"Shigemi",
""
],
[
"Tweedie",
"Robert J.",
""
],
[
"Yamaguchi",
"Azusa",
""
]
] |
0705.2341 | Aditi Mitra | Aditi Mitra and Andrew J. Millis | Coulomb Gas on the Keldysh Contour: Anderson-Yuval-Hamann representation
of the Nonequilibrium Two Level System | discussion and references added, to appear in PRB | Phys. Rev. B 76, 085342 (2007) | 10.1103/PhysRevB.76.085342 | null | cond-mat.mes-hall | null | The nonequilibrium tunnelling center model of a localized electronic level
coupled to a fluctuating two-state system and to two electronic reservoirs, is
solved via an Anderson-Yuval-Hamann mapping onto a plasma of alternating
positive and negative charges time-ordered along the two "Keldysh" contours
needed to describe nonequilibrium physics. The interaction between charges
depends both on whether their time separation is small or large compared to a
dephasing scale defined in terms of the chemical potential difference between
the electronic reservoirs and on whether their time separation is larger or
smaller than a decoherence scale defined in terms of the current flowing from
one reservoir to another. A renormalization group transformation appropriate to
the nonequilibrium problem is defined. An important feature is the presence in
the model of a new coupling, essentially the decoherence rate, which acquires
an additive renormalization similar to that of the energy in equilibrium
problems. The method is used to study interplay between the dephasing-induced
formation of independent resonances tied to the two chemical potentials and the
decoherence which cuts off the scaling and leads to effectively classical
long-time behavior. We determine the effect of departures from equilibrium on
the localization-delocalization phase transition.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 12:25:45 GMT"
},
{
"version": "v2",
"created": "Fri, 17 Aug 2007 22:14:16 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Mitra",
"Aditi",
""
],
[
"Millis",
"Andrew J.",
""
]
] |
0705.2342 | Ognyan Oreshkov | Ognyan Oreshkov, Todd A. Brun | Continuous quantum error correction for non-Markovian decoherence | 16 pages, 4 figures, minor typos corrected, references updated | Phys. Rev. A 76, 022318 (2007) | 10.1103/PhysRevA.76.022318 | null | quant-ph | null | We study the effect of continuous quantum error correction in the case where
each qubit in a codeword is subject to a general Hamiltonian interaction with
an independent bath. We first consider the scheme in the case of a trivial
single-qubit code, which provides useful insights into the workings of
continuous error correction and the difference between Markovian and
non-Markovian decoherence. We then study the model of a bit-flip code with each
qubit coupled to an independent bath qubit and subject to continuous
correction, and find its solution. We show that for sufficiently large
error-correction rates, the encoded state approximately follows an evolution of
the type of a single decohering qubit, but with an effectively decreased
coupling constant. The factor by which the coupling constant is decreased
scales quadratically with the error-correction rate. This is compared to the
case of Markovian noise, where the decoherence rate is effectively decreased by
a factor which scales only linearly with the rate of error correction. The
quadratic enhancement depends on the existence of a Zeno regime in the
Hamiltonian evolution which is absent in purely Markovian dynamics. We analyze
the range of validity of this result and identify two relevant time scales.
Finally, we extend the result to more general codes and argue that the
performance of continuous error correction will exhibit the same qualitative
characteristics.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 18:05:23 GMT"
},
{
"version": "v2",
"created": "Tue, 21 Aug 2007 02:58:52 GMT"
},
{
"version": "v3",
"created": "Wed, 29 Aug 2007 18:28:02 GMT"
}
] | 2008-08-24T00:00:00 | [
[
"Oreshkov",
"Ognyan",
""
],
[
"Brun",
"Todd A.",
""
]
] |
0705.2343 | E. Javier Elizondo | Pedro Luis del Angel, E. Javier Elizondo | On the motive of certain subvarieties of fixed flags | 8 pages, 2 figures | null | null | null | math.AG math.AT | null | We compute de Chow motive of certain subvarieties of the flags manifold and
show that it is an Artin motive.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 12:31:18 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"del Angel",
"Pedro Luis",
""
],
[
"Elizondo",
"E. Javier",
""
]
] |
0705.2344 | Christian Maes | Christian Maes and Karel Neto\v{c}n\'y | Canonical structure of dynamical fluctuations in mesoscopic
nonequilibrium steady states | 6 pages; extension with an example added, a section removed | Europhys. Lett. 82 (2008) 30003 | 10.1209/0295-5075/82/30003 | null | cond-mat.stat-mech cond-mat.soft | null | We give the explicit structure of the functional governing the dynamical
density and current fluctuations for a mesoscopic system in a nonequilibrium
steady state. Its canonical form determines a generalised Onsager-Machlup
theory. We assume that the system is described as a Markov jump process
satisfying a local detailed balance condition such as typical for stochastic
lattice gases and for chemical networks. We identify the entropy current and
the traffic between the mesoscopic states as extra terms in the fluctuation
functional with respect to the equilibrium dynamics. The density and current
fluctuations are coupled in general, except close to equilibrium where their
decoupling explains the validity of entropy production principles.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 12:47:51 GMT"
},
{
"version": "v2",
"created": "Wed, 26 Sep 2007 14:40:09 GMT"
}
] | 2015-05-07T00:00:00 | [
[
"Maes",
"Christian",
""
],
[
"Netočný",
"Karel",
""
]
] |
0705.2345 | Manuel Lladser | Manuel Lladser | Uniqueness of polynomial canonical representations | Final version to appear in the proceedings of the 2007 International
Conference on Analysis of Algorithms | null | null | null | math.CV math.CO math.PR | null | Let P(z) and Q(y) be polynomials of the same degree k>=1 in the complex
variables z and y, respectively. In this extended abstract we study the
non-linear functional equation P(z)=Q(y(z)), where y(z) is restricted to be
analytic in a neighborhood of z=0. We provide sufficient conditions to ensure
that all the roots of Q(y) are contained within the range of y(z) as well as to
have y(z)=z as the unique analytic solution of the non-linear equation. Our
results are motivated from uniqueness considerations of polynomial canonical
representations of the phase or amplitude terms of oscillatory integrals
encountered in the asymptotic analysis of the coefficients of mixed powers and
multivariable generating functions via saddle-point methods. Uniqueness shall
prove important for developing algorithms to determine the Taylor coefficients
of the terms appearing in these representations. The uniqueness of Levinson's
polynomial canonical representations of analytic functions in several variables
follows as a corollary of our one-complex variables results.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:05:14 GMT"
}
] | 2007-06-13T00:00:00 | [
[
"Lladser",
"Manuel",
""
]
] |
0705.2346 | Jonas Persson | Jonas Persson | Strings as sigma models and in the tensionless limit | PhD Thesis, viii+127 pages | null | null | UUITP-09/07 | hep-th | null | This thesis considers two different aspects of string theory, the tensionless
limit of the string and supersymmetric sigma models. The tensionless limit is
used to find a IIB supergravity background generated by a tensionless string.
Quantization of the tensionless string in a pp-wave background is performed and
the tensionless limit is found to commute with quantization. Further, the sigma
model with N=(2,2) extended world-sheet supersymmetry is considered and the
requirement on the target space to have a bi-Hermitean geometry is reviewed. It
is shown that the equivalence between bi-Hermitean geometry and generalized
Kahler follows, in this context, from the equivalence between the Lagrangian-
and Hamiltonian formulation of the model. Moreover, the explicit T-duality
transformation in the Hamiltonian formulation of the sigma model is constructed
and shown to be a symplectomorphism. Under certain assumptions, the amount of
extended supersymmetry present in the sigma model is shown to be preserved
under T-duality. Further, by requiring N=(2,2) extended supersymmetry in a
first order formulation of the sigma model an intriguing geometrical structure
arises and in a special case generalized complex geometry is found to be
contained in the new framework.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:16:07 GMT"
}
] | 2009-04-16T00:00:00 | [
[
"Persson",
"Jonas",
""
]
] |
0705.2347 | Sean McReynolds | Sean McReynolds | Five-dimensional vector-coupled supergravity on a manifold with boundary | 18 pages | Mod.Phys.Lett.A22:2247-2263,2007 | 10.1142/S0217732307024292 | null | hep-th | null | We consider the bosonic and fermionic symmetries of five-dimensional Maxwell-
and Yang-Mills-Einstein supergravity theories on a spacetime with boundaries
(isomorphic to M x S1/Z2). Due to the appearance of the "Chern-Simons" term,
the classical action is not generally invariant under gauge and
supersymmetries. Once bulk vector fields are allowed to propagate on the
boundaries, there is an "inflow" governed by the rank-3 symmetric tensor that
defines the five-dimensional theories. We discuss the requirements that
invariance of the action imposes on new matter content and boundary conditions.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:06:15 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"McReynolds",
"Sean",
""
]
] |
0705.2348 | Simone Melchionna | John Russo, Simone Melchionna, Francesco De Luca, Cinzia Casieri | Water confined in nanopores: spontaneous formation of microcavities | null | null | 10.1103/PhysRevB.76.195403 | null | cond-mat.soft | null | Molecular Dynamics simulations of water confined in nanometer sized,
hydrophobic channels show that water forms localized cavities for pore diameter
~ 2.0 nm. The cavities present non-spherical shape and lay preferentially
adjacent to the confining wall inducing a peculiar form to the liquid exposed
surface. The regime of localized cavitation appears to be correlated with the
formation of a vapor layer, as predicted by the Lum-Chandler-Weeks theory,
implying partial filling of the pore.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:06:51 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Russo",
"John",
""
],
[
"Melchionna",
"Simone",
""
],
[
"De Luca",
"Francesco",
""
],
[
"Casieri",
"Cinzia",
""
]
] |
0705.2349 | Yasuhiro Tanaka | Yasuhiro Tanaka and Kenji Yonemitsu | Effects of Electron-Lattice Coupling on Charge Order in \theta-(ET)2X | null | Journal of the Physical Society of Japan Vol.76 No.5 (2007) 053708 | 10.1143/JPSJ.76.053708 | null | cond-mat.str-el | null | Charge ordering accompanied by lattice distortion in quasi-two dimensional
organic conductors \theta-(ET)2X (ET=BEDT-TTF) is studied by using an extended
Hubbard model with Peierls-type electron-lattice couplings within the
Hartree-Fock approximation. It is found that the horizontal-stripe
charge-ordered state, which is experimentally observed in
\theta-(ET)2RbZn(SCN)4, is stabilized by the self-consistently determined
lattice distortion. Furthermore, in the presence of the anisotropy in
nearest-neighbor Coulomb interactions Vij, the horizontal charge order becomes
more stable than any other charge patterns such as diagonal, vertical and
3-fold-type states. At finite temperatures, we compare the free energies of
various charge-ordered states and find a first-order transition from a metallic
state with 3-fold charge order to the insulating state with the horizontal
charge order. The role of lattice degrees of freedom in the realization of the
horizontal charge order and the relevance to experiments on \theta-(ET)2X are
discussed.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:07:55 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Tanaka",
"Yasuhiro",
""
],
[
"Yonemitsu",
"Kenji",
""
]
] |
0705.2350 | Gonzalo Agustin Alvarez | Gonzalo A. Alvarez | Decoherence of many-spin systems in NMR: From molecular characterization
to an environmentally induced quantum dynamical phase transition | PhD Thesis, Universidad Nacional de Cordoba, 2007. 147 pages, 45
figures; arXiv admin note: The size of the PDF file apparently causes
problems with PDF browser plug-ins. Be sure to instead download and open the
PDF in a separate application | null | null | null | cond-mat.mes-hall physics.chem-ph quant-ph | null | The control of open quantum systems has a fundamental relevance for fields
ranging from quantum information processing to nanotechnology. Typically, the
system whose coherent dynamics one wants to manipulate, interacts with an
environment that smoothly degrades its quantum dynamics. Thus, a precise
understanding of the inner mechanisms of this process, called "decoherence", is
critical to develop strategies to control the quantum dynamics. In this thesis
we solved the generalized Liouville-von Neumann quantum master equation to
obtain the dynamics of many-spin systems interacting with a spin bath. We also
solve the spin dynamics within the Keldysh formalism. Both methods lead to
identical solutions and together gave us the possibility to obtain numerous
physical predictions that contrast well with Nuclear Magnetic Resonance
experiments. We applied these tools for molecular characterizations,
development of new numerical methodologies and the control of quantum dynamics
in experimental implementations. But, more important, these results contributed
to fundamental physical interpretations of how quantum dynamics behaves in open
systems. In particular, we found a manifestation of an environmentally induced
quantum dynamical phase transition.
| [
{
"version": "v1",
"created": "Tue, 15 May 2007 18:40:13 GMT"
}
] | 2007-06-20T00:00:00 | [
[
"Alvarez",
"Gonzalo A.",
""
]
] |
0705.2351 | Christian Reinboth | Hans-Juergen Scheruhn, Christian Reinboth, Thomas Habel | The Use of ITIL for Process Optimisation in the IT Service Centre of
Harz University, exemplified in the Release Management Process | 7 pages, 7 figures | null | null | null | cs.OH | null | This paper details the use of the IT Infrastructure Library Framework (ITIL)
for optimising process workflows in the IT Service Centre of Harz University in
Wernigerode, Germany, exemplified by the Release Management Process. It is
described, how, during the course of a special ITIL project, the As-Is-Status
of the various original processes was documented as part of the process life
cycle and then transformed in the To-Be-Status, according to the ITIL Best
Practice Framework. It is also shown, how the ITIL framework fits into the
four-layered-process model, that could be derived from interviews with the
universities IT support staff, and how the various modified processes
interconnect with each other to form a value chain. The paper highlights the
final results of the project and gives an outlook on the future use of ITIL as
a business modelling tool in the IT Service Centre of Harz University. It is
currently being considered, whether the process model developed during the
project could be used as a reference model for other university IT centres.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:20:26 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Scheruhn",
"Hans-Juergen",
""
],
[
"Reinboth",
"Christian",
""
],
[
"Habel",
"Thomas",
""
]
] |
0705.2352 | Leonardo Giusti Dr. | Leonardo Giusti, Silvano Petrarca and Bruno Taglienti | Theta dependence of the vacuum energy in the SU(3) gauge theory from the
lattice | Plain latex, 4 pages, 2 figures | Phys.Rev.D76:094510,2007 | 10.1103/PhysRevD.76.094510 | CERN-PH-TH/2007-077, ROME-1451/2007 | hep-th hep-lat | null | We report on a precise computation of the topological charge distribution in
the SU(3) Yang--Mills theory. It is carried out on the lattice with high
statistics Monte Carlo simulations by employing the definition of the
topological charge suggested by Neuberger's fermions. We observe significant
deviations from a Gaussian distribution. Our results disfavour the theta
behaviour of the vacuum energy predicted by instanton models, while they are
compatible with the expectation from the large Nc expansion.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:30:32 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Giusti",
"Leonardo",
""
],
[
"Petrarca",
"Silvano",
""
],
[
"Taglienti",
"Bruno",
""
]
] |
0705.2353 | Anne Gentil-Beccot | Andre Martin | The status of the heavy quark systems | 21 pages, 3 figures | null | null | CERN-PH-TH/2007-069 | hep-ph | null | We review various inequalities on the order and the spacing of energy levels,
wave function at the origin, etc... which were obtained since 1977 in the
framework of the Schrodinger equation and applied to quarkonium and also to
muonic atoms and alcaline atoms. We also present a fit of mesons and baryons
made of b, c, s quarks and antiquarks, keeping the 1981 parameters and
comparing with present experimental data.
| [
{
"version": "v1",
"created": "Tue, 15 May 2007 06:40:04 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Martin",
"Andre",
""
]
] |
0705.2354 | Jean-Noel Aqua | Jean-Noel Aqua, Thomas Frisch, Alberto Verga | Nonlinear evolution of a morphological instability in a strained
epitaxial film | 4 pages, 6 figures | Phys. Rev. B 76, 165319 (2007) | 10.1103/PhysRevB.76.165319 | null | cond-mat.stat-mech cond-mat.mtrl-sci | null | A strained epitaxial film deposited on a deformable substrate undergoes a
morphological instability relaxing the elastic energy by surface diffusion. The
nonlinear and nonlocal dynamical equations of such films with wetting
interactions are derived and solved numerically in two and three dimensions.
Above some critical thickness, the surface evolves towards an array of islands
separated by a wetting layer. The island chemical potential decreases with its
volume, so that the system experiences a non-interrupted coarsening described
by power laws with a marked dimension dependence.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:44:48 GMT"
}
] | 2011-11-16T00:00:00 | [
[
"Aqua",
"Jean-Noel",
""
],
[
"Frisch",
"Thomas",
""
],
[
"Verga",
"Alberto",
""
]
] |
0705.2355 | Piero Fariselli | Ludovica Montanucci, Piero Fariselli, Pier Luigi Martelli, Ivan Rossi
and Rita Casadio | In silico evidence of the relationship between miRNAs and siRNAs | 8 pages, 2 figures | null | null | null | q-bio.BM q-bio.GN | null | Both short interfering RNAs (siRNAs) and microRNAs (miRNAs) mediate the
repression of specific sequences of mRNA through the RNA interference pathway.
In the last years several experiments have supported the hypothesis that siRNAs
and miRNAs may be functionally interchangeable, at least in cultured cells. In
this work we verify that this hypothesis is also supported by a computational
evidence. We show that a method specifically trained to predict the activity of
the exogenous siRNAs assigns a high silencing level to experimentally
determined human miRNAs. This result not only supports the idea of siRNAs and
miRNAs equivalence but indicates that it is possible to use computational tools
developed using synthetic small interference RNAs to investigate endogenous
miRNAs.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:52:29 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Montanucci",
"Ludovica",
""
],
[
"Fariselli",
"Piero",
""
],
[
"Martelli",
"Pier Luigi",
""
],
[
"Rossi",
"Ivan",
""
],
[
"Casadio",
"Rita",
""
]
] |
0705.2356 | Seyong Kim | Dae Sung Hwang, Jong Hyun Kim, and Seyong Kim | Single-Spin Asymmetries in Inclusive and Exclusive Hadronic Processes | 10 pages and 1 figure | null | null | null | hep-ph | null | We investigate the single-spin asymmetries in inclusive and exclusive
processes of electron-proton scattering and electron-positron annihilation. In
the decomposition of hadronic tensor, a Lorentz symmetric spin-dependent term
is generally present. The existence of such a term implies single-spin
asymmetries in these processes and these single-spin asymmetries for baryons
can be understood in a unified manner. We argue that it is important to measure
the single-spin asymmetries in both inclusive and exclusive processes for the
$\Lambda$ production at the present B-factories. This will lead to the first
measurement of the structure function of the symmetric spin-dependent hadronic
tensor in these processes.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:54:42 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hwang",
"Dae Sung",
""
],
[
"Kim",
"Jong Hyun",
""
],
[
"Kim",
"Seyong",
""
]
] |
0705.2357 | T. P. Singh | T. P. Singh | The inevitable nonlinearity of quantum gravity falsifies the many-worlds
interpretation of quantum mechanics | 6 pages. Honorable Mention in Gravity Research Foundation Essay
Competition 2007. This is also a summary of a talk given at the Meeting
`Himalayan Relativity Dialogue', Mirik, India, 18-20 April, 2007. Detailed
version of this essay is in preparation | Int.J.Mod.Phys.D17:611-615,2008 | 10.1142/S0218271808012346 | null | gr-qc hep-th quant-ph | null | There are fundamental reasons as to why there should exist a reformulation of
quantum mechanics which does not refer to a classical spacetime manifold. It
follows as a consequence that quantum mechanics as we know it is a limiting
case of a more general nonlinear quantum theory, with the nonlinearity becoming
significant at the Planck mass/energy scale. This nonlinearity is responsible
for a dynamically induced collapse of the wave-function, during a quantum
measurement, and it hence falsifies the many-worlds interpretation of quantum
mechanics. We illustrate this conclusion using a mathematical model based on a
generalized Doebner-Goldin equation. The non-Hermitian part of the Hamiltonian
in this norm-preserving, nonlinear, Schrodinger equation dominates during a
quantum measurement, and leads to a breakdown of linear superposition.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 13:57:22 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Singh",
"T. P.",
""
]
] |
0705.2358 | A. I. Shushin | A. I. Shushin | Non-Markovian Stochastic Liouville equation and its Markovian
representation. Extensions of the continuous time random walk approach | 12 pages, RevTex | null | 10.1103/PhysRevE.77.031130 | null | cond-mat.stat-mech cond-mat.soft | null | Some specific features and extensions of the continuous time random walk
(CTRW) approach are analyzed in detail within the Markovian representation (MR)
and CTRW-based non-Markovian stochastic Liouville equation (SLE). In the MR
CTRW processes are represented by multidimensional Markovian ones. In this
representation the probability distribution function (PDF) W(t) of fluctuation
renewals is associated with that of reoccurrences in a certain jump state of
some Markovian controlling process. Within the MR the non-Markovian SLE, which
describes the effect of CTRW-like noise on relaxation of dynamic and stochastic
systems, is generalized to take into account the influence of relaxing systems
on statistical properties of noise. The generalized non-Markovian SLE is
applied to study two modifications of the CTRW approach. One of them considers
the cascaded CTRWs in which the controlling process is actually CTRW-like one
controlled by another CTRW process, controlled in turn by the third one, etc.
Within the MR simple expression for the PDF W(t) of total controlling process
is obtained in terms of Markovian variants of controlling PDFs in the cascade.
The expression is shown to be especially simple and instructive in the case of
anomalous processes determined by long time tailed W(t). The cascaded CTRWs can
model the effect of complexity of a system on relaxation kinetics (in glasses,
fractals, branching media, ultrametric structures, etc.). Another
CTRW-modification describes the kinetics of processes governed by fluctuating
W(t). Within the MR the problem is analyzed in a general form without
restrictive assumptions on correlations of PDFs of consecutive renewals. The
analysis shows that W(t) can strongly affect the kinetics of the process.
Possible manifestations of this effect are discussed.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:02:23 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Shushin",
"A. I.",
""
]
] |
0705.2359 | Clement Pryke | QUaD Collaboration: P. Ade (1), J. Bock (2 and 3), M. Bowden (1 and
4), M. L. Brown (5 and 6), G. Cahill (7), J. E. Carlstrom (8), P. G. Castro
(5 and 9), S. Church (4), T. Culverhouse (8), R. Friedman (8), K. Ganga (10),
W. K. Gear (1), J. Hinderks (4 and 11), J. Kovac (3), A. E. Lange (3), E.
Leitch (2 and 3), S. J. Melhuish (1 and 12), J. A. Murphy (7), A. Orlando
(1), R. Schwarz (8), C. O'Sullivan (7), L. Piccirillo (1 and 12), C. Pryke
(8), N. Rajguru (1 and 13), B. Rusholme (4 and 14), A. N. Taylor (5), K. L.
Thompson (4), E. Y. S. Wu (4), M. Zemcov (1 and 2) ((1) Cardiff University,
(2) JPL, (3) Caltech, (4) Stanford University, (5) University of Edinburgh,
(6) University of Cambridge, (7) National University of Ireland Maynooth, (8)
University of Chicago, (9) Universidade T\'ecnica de Lisboa, (10) Laboratoire
APC/CNRS, (11) NASA Goddard, (12) University of Manchester, (13) UCL, (14)
IPAC) | First season QUaD CMB temperature and polarization power spectra | 7 pages, 5 figures, submitted to ApJ | Astrophys.J.674:22-28, 2008 | 10.1086/524922 | null | astro-ph | null | QUaD is a bolometric CMB polarimeter sited at the South Pole, operating at
frequencies of 100 and 150 GHz. In this paper we report preliminary results
from the first season of operation (austral winter 2005). All six CMB power
spectra are presented derived as cross spectra between the 100 and 150 GHz maps
using 67 days of observation in a low foreground region of approximately 60
square degrees. This data is a small fraction of the data acquired to date. The
measured spectra are consistent with the LCDM cosmological model. We perform
jackknife tests which indicate that the observed signal has negligible
contamination from instrumental systematics. In addition by using a frequency
jackknife we find no evidence for foreground contamination.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 18:03:57 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"QUaD Collaboration",
"",
""
],
[
"Ade",
"P.",
"",
"2 and 3"
],
[
"Bock",
"J.",
"",
"2 and 3"
],
[
"Bowden",
"M.",
"",
"1 and\n 4"
],
[
"Brown",
"M. L.",
"",
"5 and 6"
],
[
"Cahill",
"G.",
"",
"5 and 9"
],
[
"Carlstrom",
"J. E.",
"",
"5 and 9"
],
[
"Castro",
"P. G.",
"",
"5 and 9"
],
[
"Church",
"S.",
"",
"4 and 11"
],
[
"Culverhouse",
"T.",
"",
"4 and 11"
],
[
"Friedman",
"R.",
"",
"4 and 11"
],
[
"Ganga",
"K.",
"",
"4 and 11"
],
[
"Gear",
"W. K.",
"",
"4 and 11"
],
[
"Hinderks",
"J.",
"",
"4 and 11"
],
[
"Kovac",
"J.",
"",
"2 and 3"
],
[
"Lange",
"A. E.",
"",
"2 and 3"
],
[
"Leitch",
"E.",
"",
"2 and 3"
],
[
"Melhuish",
"S. J.",
"",
"1 and 12"
],
[
"Murphy",
"J. A.",
"",
"1 and 12"
],
[
"Orlando",
"A.",
"",
"1 and 12"
],
[
"Schwarz",
"R.",
"",
"1 and 12"
],
[
"O'Sullivan",
"C.",
"",
"1 and 12"
],
[
"Piccirillo",
"L.",
"",
"1 and 12"
],
[
"Pryke",
"C.",
"",
"1 and 13"
],
[
"Rajguru",
"N.",
"",
"1 and 13"
],
[
"Rusholme",
"B.",
"",
"4 and 14"
],
[
"Taylor",
"A. N.",
"",
"1 and 2"
],
[
"Thompson",
"K. L.",
"",
"1 and 2"
],
[
"Wu",
"E. Y. S.",
"",
"1 and 2"
],
[
"Zemcov",
"M.",
"",
"1 and 2"
]
] |
0705.2360 | Zhifeng Xie | Yue-Liang Wu, Zhi-Feng Xie | A Three-Flavor AdS/QCD Model with a Back-Reacted Geometry | 10 pages, 2 figures; references revised, minor change for caption of
fig 2 | JHEP 0710:009,2007 | 10.1088/1126-6708/2007/10/009 | null | hep-ph | null | A fully back-reaction geometry model of AdS/QCD including the strange quark
is described. We find that with the inclusion of the strange quark the impact
on the metric is very small and the final predictions are changed only
negligibly.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:14:08 GMT"
},
{
"version": "v2",
"created": "Sat, 2 Jun 2007 08:44:30 GMT"
}
] | 2009-04-21T00:00:00 | [
[
"Wu",
"Yue-Liang",
""
],
[
"Xie",
"Zhi-Feng",
""
]
] |
0705.2361 | Petre Birtea | Petre Birtea, Mircea Puta, Razvan Micu Tudoran | Periodic orbits in the case of a zero eigenvalue | 6 pages, no figures | null | null | null | math.DS math-ph math.MP | null | We will show that if a dynamical system has enough constants of motion then a
Moser-Weinstein type theorem can be applied for proving the existence of
periodic orbits in the case when the linearized system is degenerate.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:14:15 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Birtea",
"Petre",
""
],
[
"Puta",
"Mircea",
""
],
[
"Tudoran",
"Razvan Micu",
""
]
] |
0705.2362 | Enrico Massa | Enrico Massa, Danilo Bruno and Enrico Pagani | Geometric control theory I: mathematical foundations | replaced by the more recent article arXiv:1503.08808 | null | null | null | math.OC math-ph math.MP | null | A geometric setup for control theory is presented. The argument is developed
through the study of the extremals of action functionals defined on piecewise
differentiable curves, in the presence of differentiable non-holonomic
constraints. Special emphasis is put on the tensorial aspects of the theory. To
start with, the kinematical foundations, culminating in the so called
variational equation, are put on geometrical grounds, via the introduction of
the concept of infinitesimal control . On the same basis, the usual
classification of the extremals of a variational problem into normal and
abnormal ones is also rationalized, showing the existence of a purely
kinematical algorithm assigning to each admissible curve a corresponding
abnormality index, defined in terms of a suitable linear map. The whole
machinery is then applied to constrained variational calculus. The argument
provides an interesting revisitation of Pontryagin maximum principle and of the
Erdmann-Weierstrass corner conditions, as well as a proof of the classical
Lagrange multipliers method and a local interpretation of Pontryagin's
equations as dynamical equations for a free (singular) Hamiltonian system. As a
final, highly non-trivial topic, a sufficient condition for the existence of
finite deformations with fixed endpoints is explicitly stated and proved.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:22:16 GMT"
},
{
"version": "v2",
"created": "Tue, 4 Dec 2007 07:39:36 GMT"
},
{
"version": "v3",
"created": "Fri, 15 May 2015 16:24:45 GMT"
}
] | 2015-05-18T00:00:00 | [
[
"Massa",
"Enrico",
""
],
[
"Bruno",
"Danilo",
""
],
[
"Pagani",
"Enrico",
""
]
] |
0705.2363 | Marten Wegkamp | Marten Wegkamp | Lasso type classifiers with a reject option | Published at http://dx.doi.org/10.1214/07-EJS058 in the Electronic
Journal of Statistics (http://www.i-journals.org/ejs/) by the Institute of
Mathematical Statistics (http://www.imstat.org) | Electronic Journal of Statistics 2007, Vol. 1, 155-168 | 10.1214/07-EJS058 | IMS-EJS-EJS_2007_58 | stat.ML | null | We consider the problem of binary classification where one can, for a
particular cost, choose not to classify an observation. We present a simple
proof for the oracle inequality for the excess risk of structural risk
minimizers using a lasso type penalty.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:23:17 GMT"
}
] | 2009-09-29T00:00:00 | [
[
"Wegkamp",
"Marten",
""
]
] |
0705.2364 | Pavlos Pasipoularides | K. Farakos, G. Koutsoumbas and P. Pasipoularides | Graviton localization and Newton's law for brane models with a
non-minimally coupled bulk scalar field | 17 pages, revised version | Phys.Rev.D76:064025,2007 | 10.1103/PhysRevD.76.064025 | null | hep-th | null | Brane world models with a non-minimally coupled bulk scalar field have been
studied recently. In this paper we consider metric fluctuations around an
arbitrary gravity-scalar background solution, and we show that the
corresponding spectrum includes a localized zero mode which strongly depends on
the profile of the background scalar field. For a special class of solutions,
with a warp factor of the RS form, we solve the linearized Einstein equations,
for a point-like mass source on the brane, by using the brane bending
formalism. We see that general relativity on the brane is recovered only if we
impose restrictions on the parameter space of the models under consideration.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:27:16 GMT"
},
{
"version": "v2",
"created": "Mon, 23 Jul 2007 18:07:22 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Farakos",
"K.",
""
],
[
"Koutsoumbas",
"G.",
""
],
[
"Pasipoularides",
"P.",
""
]
] |
0705.2365 | Salvatore Antoci | S. Antoci, L. Mihich | The issue of photons in dielectrics: Hamiltonian viewpoint | 12 pages, one figure; text to appear in Nuovo Cimento B | Nuovo Cim.B122:413-424, 2007 | 10.1393/ncb/i2007-10367-9 | null | gr-qc quant-ph | null | The definition of the photon in the vacuum of general relativity provided by
Kermack et al. and by Synge is extended to nondispersive, nonhomogeneous,
isotropic dielectrics in arbitrary motion by Hamiltonian methods that rely on
Gordon's effective metric. By these methods the old dilemma, whether the
momentum-energy vector of the photon in dielectrics is timelike or spacelike in
character, is shown to reappear under a novel guise.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 17:30:35 GMT"
},
{
"version": "v2",
"created": "Thu, 25 Oct 2007 14:56:46 GMT"
}
] | 2010-11-11T00:00:00 | [
[
"Antoci",
"S.",
""
],
[
"Mihich",
"L.",
""
]
] |
0705.2366 | Ralph Blumenhagen | Nikolas Akerblom, Ralph Blumenhagen, Dieter Lust, Maximilian
Schmidt-Sommerfeld | Instantons and Holomorphic Couplings in Intersecting D-brane Models | 28 pages, 5 figures | JHEP 0708:044,2007 | 10.1088/1126-6708/2007/08/044 | MPP-2007-57, LMU-ASC 31/07 | hep-th | null | We clarify certain aspects and discuss extensions of the recently introduced
string D-instanton calculus (hep-th/0609191). The one-loop determinants are
related to one-loop open string threshold corrections in intersecting D6-brane
models. Utilising a non-renormalisation theorem for the holomorphic Wilsonian
gauge kinetic functions, we derive a number of constraints for the moduli
dependence of the matter field Kaehler potentials of intersecting D6-brane
models on the torus. Moreover, we compute string one-loop corrections to the
Fayet-Iliopoulos terms on the D6-branes finding that they are proportional to
the gauge threshold corrections. Employing these results, we discuss the issue
of holomorphy for E2-instanton corrections to the superpotential. Eventually,
we discuss E2-instanton corrections to the gauge kinetic functions and the
FI-terms.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:42:17 GMT"
}
] | 2009-10-07T00:00:00 | [
[
"Akerblom",
"Nikolas",
""
],
[
"Blumenhagen",
"Ralph",
""
],
[
"Lust",
"Dieter",
""
],
[
"Schmidt-Sommerfeld",
"Maximilian",
""
]
] |
0705.2367 | Mark Collings | J. D. Thrower, D. J. Burke, M. P. Collings, A. Dawes, P. J. Holtom, F.
Jamme, P. Kendall, W. A. Brown, I. P. Clark, H. J. Fraser, M. R. S.
McCoustra, N. J. Mason and A. W. Parker | Desorption of hot molecules from photon irradiated interstellar ices | 23 pages, including 4 figures; submitted to ApJ | null | 10.1086/524097 | null | astro-ph | null | We present experimental measurements of photodesorption from ices of
astrophysical relevance. Layers of benzene and water ice were irradiated with a
laser tuned to an electronic transition in the benzene molecule. The
translational energy of desorbed molecules was measured by time-of-flight (ToF)
mass spectrometry. Three distinct photodesorption processes were identified - a
direct adsorbate-mediated desorption producing benzene molecules with a
translational temperature of around 1200 K, an indirect adsorbate-mediated
desorption resulting in water molecules with a translational temperature of
around 450 K, and a substrate-mediated desorption of both benzene and water
producing molecules with translational temperatures of around 530 K and 450 K
respectively. The translational temperature of each population of desorbed
molecules is well above the temperature of the ice matrix. The implications for
gas-phase chemistry in the interstellar medium are discussed.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:46:34 GMT"
},
{
"version": "v2",
"created": "Tue, 28 Aug 2007 17:19:02 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Thrower",
"J. D.",
""
],
[
"Burke",
"D. J.",
""
],
[
"Collings",
"M. P.",
""
],
[
"Dawes",
"A.",
""
],
[
"Holtom",
"P. J.",
""
],
[
"Jamme",
"F.",
""
],
[
"Kendall",
"P.",
""
],
[
"Brown",
"W. A.",
""
],
[
"Clark",
"I. P.",
""
],
[
"Fraser",
"H. J.",
""
],
[
"McCoustra",
"M. R. S.",
""
],
[
"Mason",
"N. J.",
""
],
[
"Parker",
"A. W.",
""
]
] |
0705.2368 | Kirill Bronnikov | K.A. Bronnikov, I.G. Dymnikova | Regular homogeneous T-models with vacuum dark fluid | 13 pages, no figures, Latex | Class.Quant.Grav.24:5803-5816,2007 | 10.1088/0264-9381/24/23/005 | null | gr-qc | null | We present the class of regular homogeneous T-models with vacuum dark fluid,
associated with a variable cosmological term. The vacuum fluid is defined by
the symmetry of its stress-energy tensor, i.e., its invariance under Lorentz
boosts in a distinguished spatial direction (p_j=-\rho), which makes this fluid
essentially anisotropic and allows its density to evolve. Typical features of
homogeneous regular T-models are: the existence of a Killing horizon; beginning
of the cosmological evolution from a null bang at the horizon; the existence of
a regular static pre-bang region visible to cosmological observers; creation of
matter from anisotropic vacuum, accompanied by very rapid isotropization. We
study in detail the spherically symmetric regular T-models on the basis of a
general exact solution for a mixture of the vacuum fluid and dustlike matter
and apply it to give numerical estimates for a particular model which
illustrates the ability of cosmological T-models to satisfy the observational
constraints.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:47:48 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bronnikov",
"K. A.",
""
],
[
"Dymnikova",
"I. G.",
""
]
] |
0705.2369 | Marius de Leeuw | M. de Leeuw | Coordinate Bethe Ansatz for the String S-Matrix | 25 Pages, plain LaTeX, 4 Figures. Mostly added references, fixed
typos | J.Phys.A40:14413-14432,2007 | 10.1088/1751-8113/40/48/008 | ITP-UU-07/28, Spin 07/18 | hep-th | null | We use the coordinate Bethe ansatz approach to derive the nested Bethe
equations corresponding to the recently found S-matrix for strings in AdS5 x
S5, compatible with centrally extended su(2|2) symmetry.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:50:28 GMT"
},
{
"version": "v2",
"created": "Tue, 24 Jul 2007 08:09:59 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"de Leeuw",
"M.",
""
]
] |
0705.2370 | Kenneth R. Brown | Kenneth R. Brown | Energy protection arguments fail in the interaction picture | 7 pages, minor changes to figures and text | null | 10.1103/PhysRevA.76.022327 | null | quant-ph | null | Spin Hamiltonians with degenerate ground states are one potential system for
the storage of quantum information at low temperatures. Trapped ions can be
used to simulate the dynamics of these Hamiltonians, but the
coherence-preserving properties will be lost. This illustrates that a quantum
simulation performed in an interaction frame will not thermalize with its
environment.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 14:58:43 GMT"
},
{
"version": "v2",
"created": "Fri, 27 Jul 2007 15:47:58 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Brown",
"Kenneth R.",
""
]
] |
0705.2371 | Takahiro Kitayama | Takahiro Kitayama | Normalization of twisted Alexander invariants | 15 pages, 1 figure; corrected the error about displaying a figure; 18
pages, 1 figure, modified the normalization of invariants and added a certain
theorem; 19 pages, 1 figure, improved Theorem 6.6; to appear in International
Journal of Mathematics | null | null | null | math.GT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Twisted Alexander invariants of knots are well-defined up to multiplication
of units. We get rid of this multiplicative ambiguity via a combinatorial
method and define normalized twisted Alexander invariants. We then show that
the invariants coincide with sign-determined Reidemeister torsion in a
normalized setting, and refine the duality theorem. We further obtain necessary
conditions on the invariants for a knot to be fibered, and study behavior of
the highest degrees of the invariants.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 18:41:53 GMT"
},
{
"version": "v2",
"created": "Thu, 17 May 2007 10:39:31 GMT"
},
{
"version": "v3",
"created": "Thu, 24 Jan 2008 17:58:21 GMT"
},
{
"version": "v4",
"created": "Thu, 5 Mar 2009 06:04:01 GMT"
},
{
"version": "v5",
"created": "Sun, 5 Jul 2015 06:52:39 GMT"
}
] | 2015-07-07T00:00:00 | [
[
"Kitayama",
"Takahiro",
""
]
] |
0705.2372 | Grzegorz Brona | G. Brona (for the COMPASS Collaboration) | Measurement of the gluon polarisation at COMPASS | 4 pages, To appear in the proceedings of 42st Rencontres de Moriond
on QCD and Hadronic interactions, La Thuile, Aosta Valley, Italy, 17-24 Mar
2006 | null | null | null | hep-ex | null | COMPASS experiment measurements of the gluon polarisation in nucleon,
DeltaG/G are reviewed. Two different approaches based on tagging the Photon
Gluon Fusion process are described. They rely on the open charm meson or
high-p_T hadron pairs detection.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:01:50 GMT"
}
] | 2019-08-13T00:00:00 | [
[
"Brona",
"G.",
"",
"for the COMPASS Collaboration"
]
] |
0705.2373 | Luis Borbonet | L. Alejandro Correa-Borbonet | Bekenstein Bound and Spectral Geometry | 4 pages. References and few comments added | null | null | null | hep-th | null | In this letter it is proposed to study the Bekenstein's $\xi(4)$ calculation
of the $S/E$ bound for more general geometries. It is argued that, using some
relations among eigenvalues obtained in the context of Spectral Geometry, it is
possible to estimate $\xi(4)$ without an exact analytical knowledge of the
spectrum. Finally it is claimed that isospectrality can define a class of
domains with the same ratio $S/E$.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:05:35 GMT"
},
{
"version": "v2",
"created": "Thu, 6 Dec 2007 21:23:04 GMT"
}
] | 2007-12-06T00:00:00 | [
[
"Correa-Borbonet",
"L. Alejandro",
""
]
] |
0705.2374 | Matteo G. A. Paris | Stefano Olivares, Federico Casagrande, Alfredo Lulli, Matteo G. A.
Paris | Reconstruction of the photon distribution in a micromaser | 4 pages, 4 figures | Europhys. Lett. 80, 64002 (2007) | 10.1209/0295-5075/80/64002 | null | quant-ph | null | We suggest an iterative, maximum-likelihood-based, method to reconstruct the
photon number distribution of the steady state cavity field of a micromaser
starting from the statistics of the atoms leaving the cavity after the
interaction. The scheme is based on measuring the atomic populations of probe
atoms for different interaction times and works effectively using a small
number of atoms and a limited sampling of the interaction times. The method has
been tested by numerically simulated experiments showing that it may be
reliably used in any micromaser regime leading to high-fidelity reconstructions
for single-peaked distributions as well as for double-peaked ones and for
trapping states.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:07:13 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Olivares",
"Stefano",
""
],
[
"Casagrande",
"Federico",
""
],
[
"Lulli",
"Alfredo",
""
],
[
"Paris",
"Matteo G. A.",
""
]
] |
0705.2375 | Adrian Iovan | A. Iovan, S. Andersson, Yu. G. Naidyuk, A. Vedyaev, B. Dieny, and V.
Korenivski | Spin Diode Based on Fe/MgO Double Tunnel Junction | 14 pages | null | 10.1021/nl072676z | null | cond-mat.mes-hall | null | We demonstrate a spin diode consisting of a semiconductor free nano-scale
Fe/MgO-based double tunnel junction. The device exhibits a near perfect
spin-valve effect combined with a strong diode effect. The mechanism consistent
with our data is resonant tunneling through discrete states in the middle
ferromagnetic layer sandwiched by tunnel barriers of different spin-dependent
transparency. The observed magneto-resistance is record high, ~4000%,
essentially making the structure an on/off spin-switch. This, combined with the
strong diode effect, ~100, offers a new device that should be promising for
such technologies as magnetic random access memory and re-programmable logic.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:11:05 GMT"
},
{
"version": "v2",
"created": "Thu, 18 Oct 2007 20:09:25 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Iovan",
"A.",
""
],
[
"Andersson",
"S.",
""
],
[
"Naidyuk",
"Yu. G.",
""
],
[
"Vedyaev",
"A.",
""
],
[
"Dieny",
"B.",
""
],
[
"Korenivski",
"V.",
""
]
] |
0705.2376 | Daniel Gerber | J.L.F. Barbon and D. Gerber | A note on the topological order of noncommutative Hall fluids | 14 pages | null | 10.1142/S0217751X07038050 | IFT/2007-07-25 | cond-mat.mes-hall hep-th | null | We evaluate the ground state degeneracy of noncommutative Chern-Simons models
on the two-torus, a quantity that is interpreted as the "topological order" of
associated phases of Hall fluids. We define the noncommutative theory via
T-duality from an ordinary Chern-Simons model with non-abelian 't Hooft
magnetic fluxes. Motivated by this T-duality, we propose a discrete family of
noncommutative, non-abelian fluid models, arising as a natural generalization
of the standard noncommutative Chern-Simons effective models. We compute the
topological order for these universality classes, and comment on their possible
microscopic interpretation.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:11:35 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Barbon",
"J. L. F.",
""
],
[
"Gerber",
"D.",
""
]
] |
0705.2377 | Benjamin Audoux | Benjamin Audoux | Singular link Floer homology | 29 pages, many figures | Algebr. Geom. Topol. 9 (2009) 495-535 | 10.2140/agt.2009.9.495 | null | math.GT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We define a grid presentation for singular links i.e. links with a finite
number of rigid transverse double points. Then we use it to generalize link
Floer homology to singular links. Besides the consistency of its definition, we
prove that this homology is acyclic under some conditions which naturally make
its Euler characteristic vanish.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:52:21 GMT"
},
{
"version": "v2",
"created": "Sat, 16 Jun 2007 16:49:13 GMT"
},
{
"version": "v3",
"created": "Thu, 20 Dec 2007 18:24:22 GMT"
},
{
"version": "v4",
"created": "Tue, 1 Apr 2008 09:14:09 GMT"
},
{
"version": "v5",
"created": "Fri, 24 Apr 2009 09:35:23 GMT"
},
{
"version": "v6",
"created": "Sun, 29 Oct 2017 18:36:31 GMT"
}
] | 2017-10-31T00:00:00 | [
[
"Audoux",
"Benjamin",
""
]
] |
0705.2378 | Oleg Kargaltsev | O. Kargaltsev and G. G. Pavlov | X-ray emission from PSR J1809-1917 and its pulsar wind nebula, possibly
associated with the TeV gamma-ray source HESS J1809-193 | 13 pages, 10 figures and 3 tables, submitted to ApJ. Version with the
high-resolution figures is available at
http://www.astro.psu.edu/users/green/J1809/ms_astroph.pdf | null | 10.1086/521814 | null | astro-ph | null | We detected X-ray emission from the 50-kyr-old pulsar J1809-1917 and resolved
its pulsar wind nebula (PWN) with Chandra. The pulsar spectrum fits PL+BB model
with the photon index of 1.2 and the BB temperature of 2 MK for n_{H}=0.7\times
10^{22} cm^{-2}. The luminosities are(4\pm 1)\times 10^{31} ergs s^{-1} for the
PL component (in the 0.5-8 keV band) and ~1\times 10^{32} ergs s^{-1} for the
BB component (bolometric) at a plausible distance of 3.5 kpc. The bright inner
PWN component of a 3''\times12'' size is elongated in the north-south
direction, with the pulsar close to its south end. This component is immersed
in a larger (20''\times40''), similarly elongated outer PWN component of lower
surface brightness. The elongated shape of the compact PWN can be explained by
the ram pressure confinement of the pulsar wind due to the supersonic motion of
the pulsar. The PWN spectrum fits a PL model with photon index of 1.4\pm0.1 and
0.5-8 keV luminosity of 4\times10^{32} ergs s^{-1}. The compact PWN appears to
be inside a large-scale (~4'\times4') emission more extended to the south of
the pulsar, i.e. in the direction of the alleged pulsar motion. To explain the
extended X-ray emission ahead of the moving pulsar, one has to invoke strong
intrinsic anisotropy of the pulsar wind or assume that this emission comes from
a relic PWN swept by the asymmetrical reverse SNR shock. The pulsar and its PWN
are located within the extent of the unidentified TeV source HESS J1809-193
whose brightest part is offset by ~8' to the south of the pulsar, i.e. in the
same direction as the large-scale X-ray emission. Although the association
between J1809-1917 and HESS J1809-193 is plausible, an alternative source of
relativistic electrons powering HESS J1809-193 might be the serendipitously
discovered X-ray source CXOU J180940.7-192544.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:18:02 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kargaltsev",
"O.",
""
],
[
"Pavlov",
"G. G.",
""
]
] |
0705.2379 | Victor H. Moll | Tewodros Amdeberhan, Luis Medina and Victor H. Moll | The integrals in Gradshteyn and Ryzhik. Part 5: Some trigonometric
integrals | 13 pages | null | null | null | math.CA | null | We present evalauations and provide proofs of definite integrals involving
the function x^p cos^n x. These formulae are generalizations of 3.761.11 and
3.822.1, among others, in the classical table of integrals by I. S. Gradshteyn
and I. M. Ryzhik.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:32:49 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Amdeberhan",
"Tewodros",
""
],
[
"Medina",
"Luis",
""
],
[
"Moll",
"Victor H.",
""
]
] |
0705.2380 | Aseem Paranjape | Aseem Paranjape | A Covariant Road to Spatial Averaging in Cosmology : Scalar Corrections
to the Cosmological Equations | 8 pages; This essay received an Honourable Mention in the Gravity
Research Foundation's Essay Competition, 2007 | Int.J.Mod.Phys.D17:597-601,2008 | 10.1142/S0218271808012322 | null | gr-qc astro-ph | null | A consistent approach to Cosmology requires an explicit averaging of the
Einstein equations, to describe a homogeneous and isotropic geometry. Such an
averaging will in general modify the Einstein equations. The averaging
procedure due to Buchert has attracted considerable attention recently since it
offers the tantalizing hope of explaining the phenomenon of dark energy through
such corrections. This approach has been criticized, however, on the grounds
that its effects may be gauge artifacts. We apply the fully covariant formalism
of Zalaletdinov's Macroscopic Gravity and show that, after making some
essential gauge choices, the Cosmological equations receive \emph{spacetime
scalar} corrections which are therefore observable in principle, and further,
that the broad structure of these corrections is \emph{identical} to those
derived by Buchert.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:33:17 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Paranjape",
"Aseem",
""
]
] |
0705.2381 | Maximilian Stritzinger | Maximilian Stritzinger (1) and Jesper Sollerman (1,2) ((1) Dark
Cosmoglogy Centre, Niels Bohr Institutet, K{\o}benhavns Universitet; (2)
Stockholm Observatory) | Late-time emission of type Ia supernovae: optical and near-infrared
observations of SN 2001el | 4 pages with 2 figures plus 7 tables. Accepted for publication in A&A
letter. Constructive comments welcomed | null | 10.1051/0004-6361:20066999 | null | astro-ph | null | We present optical and near-infrared light curves of SN 2001el from 310 to
445 days past maximum light, obtained with the Very Large Telescope. The
late-time optical (UBVRI) light curves decay in a nearly linear fashion with
decay time scales of 1.43\pm0.14, 1.43\pm0.06, 1.48\pm0.06, 1.45\pm0.07, and
1.03\pm0.07 magnitudes (per hundred days) in the U, B, V, R and I bands,
respectively. In contrast, in the near-infrared (JHKs) bands the time evolution
of the flux appears to be nearly constant at these epochs. We measure decline
rates (per hundred days) of 0.19\pm0.10 and 0.17\pm0.11 magnitudes in the J and
H bands, respectively. We construct a UVOIR light curve, and find that the
late-time luminosity has a decay time scale nearly consistent with complete
depostion of positron kinetic energy. The late-time light curves of the normal
type Ia SN 2001el demonstrate the increased importance of the near-infrared
contribution. This was previously observed in the peculiar SN 2000cx, and the
results for SN 2001el thus ensure that the conclusions previously based on a
single peculiar event are applicable to normal type Ia supernovae. The measured
late-time UVOIR decline rate suggests that a majority of the positrons are
trapped within the ejecta. This results does not favor the predictions of a
weak and/or radially combed magnetic field configuration.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:04:42 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Stritzinger",
"Maximilian",
""
],
[
"Sollerman",
"Jesper",
""
]
] |
0705.2382 | Mi Xie | Yao Shen, Wu-Sheng Dai, Mi Xie | Intermediate-statistics quantum bracket, coherent state, oscillator, and
representation of angular momentum (su(2)) algebra | 12 pages, no figures. Revtex | Phys.Rev.A75:042111,2007 | 10.1103/PhysRevA.75.042111 | null | quant-ph math-ph math.MP | null | In this paper, we first discuss the general properties of an
intermediate-statistics quantum bracket, $[ u,v]_{n}=uv-e^{i2\pi /(n+1)}vu$,
which corresponds to intermediate statistics in which the maximum occupation
number of one quantum state is an arbitrary integer, $n$. A further study of
the operator realization of intermediate statistics is given. We construct the
intermediate-statistics coherent state. An intermediate-statistics oscillator
is constructed, which returns to bosonic and fermionic oscillators respectively
when $n\to \infty $ and $n=1$. The energy spectrum of such an
intermediate-statistics oscillator is calculated. Finally, we discuss the
intermediate-statistics representation of angular momentum ($su(2)$) algebra.
Moreover, a further study of the operator realization of intermediate
statistics is given in the Appendix.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:36:11 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Shen",
"Yao",
""
],
[
"Dai",
"Wu-Sheng",
""
],
[
"Xie",
"Mi",
""
]
] |
0705.2383 | Julia Scharwaechter | J. Scharwaechter (1), A. Eckart (2), S. Pfalzner (2), I. Saviane (1),
J. Zuther (2) ((1) ESO, (2) University of Cologne, Germany) | The nearby QSO host I Zw 1: The stellar disk and adjacent objects | 11 pages, 9 figures, accepted by A&A | null | 10.1051/0004-6361:20066359 | null | astro-ph | null | The relation between tidal interactions, starbursts, and the onset and/or
fueling of active galactic nuclei (AGN) is a matter of debate. I Zw 1 is
considered as the prototypical narrow-line Seyfert 1 galaxy (NLS1) and as one
of the closest quasi-stellar objects (QSOs). With a clear spiral host and a
small companion galaxy to the west, I Zw 1 is a possible example of
minor-merger-related nuclear activity. This study investigates possible signs
of a relation between merger process, star formation activity, and AGN
properties in the case of I Zw 1. The morphology of I Zw 1 and nearby sources
is investigated via high-resolution NIR images. Color trends in the host galaxy
of I Zw 1 are discussed by means of optical-to-NIR color composites. Long-slit
spectra of the QSO nucleus of I Zw 1 and of the two nearby sources to the north
and the west of the I Zw 1 disk are analyzed. The data support the scenario of
a tidal interaction between I Zw 1 and the small companion galaxy to the west.
A concentration of blue color in the western part of the I Zw 1 host galaxy
might be the manifestation of merger-induced star formation activity. Previous
findings that the likely companion has an old evolved stellar population are
substantiated by the new data. An extension to the west of the putative
companion emerges as a separate source. The source to the north of the I Zw 1
disk is reconfirmed as a late-type foreground star. Lines in the nuclear K-band
spectrum of I Zw 1 are discussed in comparison to data prior to this article
and line fluxes are reported.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:40:14 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Scharwaechter",
"J.",
"",
"ESO"
],
[
"Eckart",
"A.",
"",
"University of Cologne, Germany"
],
[
"Pfalzner",
"S.",
"",
"University of Cologne, Germany"
],
[
"Saviane",
"I.",
"",
"ESO"
],
[
"Zuther",
"J.",
"",
"University of Cologne, Germany"
]
] |
0705.2384 | Tesfaye Abtew | T. A. Abtew, M. Zhang, and D. A. Drabold | Ab initio estimate of temperature dependence of electrical conductivity
in a model amorphous material: hydrogenated amorphous silicon | 9 pages, 8 figures, submitted to PRB Comments: corrected typos,
referee's comments included | null | 10.1103/PhysRevB.76.045212 | null | cond-mat.mtrl-sci | null | We present an ab initio calculation of the DC conductivity of amorphous
silicon and hydrogenated amorphous silicon. The Kubo-Greenwood formula is used
to obtain the DC conductivity, by thermal averaging over extended dynamical
simulation. Its application to disordered solids is discussed. The conductivity
is computed for a wide range of temperatures and doping is explored in a naive
way by shifting the Fermi level. We observed the Meyer-Neldel rule for the
electrical conductivity with E_MNR = 0.06 eV and a temperature coefficient of
resistance, TCR ~ -2.0% K^-1 for a-Si:H. In general, experimental trends are
reproduced by these calculations, and this suggests the possible utility of the
approach for modeling carrier transport in other disordered systems.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:43:16 GMT"
},
{
"version": "v2",
"created": "Thu, 17 May 2007 15:05:39 GMT"
},
{
"version": "v3",
"created": "Sun, 3 Jun 2007 15:36:50 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Abtew",
"T. A.",
""
],
[
"Zhang",
"M.",
""
],
[
"Drabold",
"D. A.",
""
]
] |
0705.2385 | Julien Barre | Julien Barre, Bruno Goncalves | Ensemble inequivalence in random graphs | 9 pages, 3 figures | Physica A 386, 212 (2007) | 10.1016/j.physa.2007.08.015 | null | cond-mat.stat-mech | null | We present a complete analytical solution of a system of Potts spins on a
random k-regular graph in both the canonical and microcanonical ensembles,
using the Large Deviation Cavity Method (LDCM). The solution is shown to be
composed of three different branches, resulting in an non-concave entropy
function.The analytical solution is confirmed with numerical Metropolis and
Creutz simulations and our results clearly demonstrate the presence of a region
with negative specific heat and, consequently, ensemble inequivalence between
the canonical and microcanonical ensembles.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:51:40 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Barre",
"Julien",
""
],
[
"Goncalves",
"Bruno",
""
]
] |
0705.2386 | Hartmut Machner | K. Kilian, S. Kliczewski, Da. Kirillov, Di.Kirillov, D. Kolev, M.
Kravcikova, T. Kutsarova, M. Lesiak, J. Lieb, H. Machner, A. Magiera, R.
Maier, G. Martinska, S. Nedev, N. Piskunov, D. Prasuhn, D. Prottic, J.
Ritman, P. von Rossen, B. J. Roy, P. Shukla, I. Sitnik, R. Siudak, R. Tsenov,
M. Ulicny, J. Urban, G. Vankova | A large acceptance scintillator detector with wavelength shifting fibre
read-out for search of eta-nucleus bound states | accepted by Nucl. Instr. Methods in Phys. Research A | Nucl.Instrum.Meth.A578:198-206,2007 | 10.1016/j.nima.2007.04.159 | null | physics.ins-det nucl-ex | null | A large acceptance scintillator detector with wavelength shifting optical
fibre readout has been designed and built to detect the decay particles of
$\eta$-nucleus bound system (the so-called $\eta$-mesic nuclei), namely,
protons and pions. The detector, named as ENSTAR detector, consists of 122
pieces of plastic scintillator of various shapes and sizes, which are arranged
in a cylindrical geometry to provide particle identification, energy loss and
coarse position information for these particles. A solid angle coverage of
$\sim$95% of total 4$\pi$ is obtained in the present design of the detector.
Monte Carlo phase space calculations performed to simulate the formation and
decay of $\eta$-mesic nuclei suggest that its decay particles, the protons and
pions are emitted with an opening angle of 150$^\circ \pm 20^\circ$, and with
energies in the range of 25 to 300 MeV and 225 to 450 MeV respectively. The
detailed GEANT simulations show that $\sim$ 80 % of the decay particles
(protons and pions) can be detected within ENSTAR. Several test measurements
using alpha source, cosmic-ray muons etc. have been carried out to study the
response of ENSTAR scintillator pieces. The in-beam tests of fully assembled
detector with proton beam of momentum 870 MeV/c from the Cooler synchrotron
COSY have been performed. The test results show that the scintillator fiber
design chosen for the detector has performed satisfactorily well. The present
article describes the detector design, simulation studies, construction details
and test results.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 15:55:49 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kilian",
"K.",
""
],
[
"Kliczewski",
"S.",
""
],
[
"Kirillov",
"Da.",
""
],
[
"Kirillov",
"Di.",
""
],
[
"Kolev",
"D.",
""
],
[
"Kravcikova",
"M.",
""
],
[
"Kutsarova",
"T.",
""
],
[
"Lesiak",
"M.",
""
],
[
"Lieb",
"J.",
""
],
[
"Machner",
"H.",
""
],
[
"Magiera",
"A.",
""
],
[
"Maier",
"R.",
""
],
[
"Martinska",
"G.",
""
],
[
"Nedev",
"S.",
""
],
[
"Piskunov",
"N.",
""
],
[
"Prasuhn",
"D.",
""
],
[
"Prottic",
"D.",
""
],
[
"Ritman",
"J.",
""
],
[
"von Rossen",
"P.",
""
],
[
"Roy",
"B. J.",
""
],
[
"Shukla",
"P.",
""
],
[
"Sitnik",
"I.",
""
],
[
"Siudak",
"R.",
""
],
[
"Tsenov",
"R.",
""
],
[
"Ulicny",
"M.",
""
],
[
"Urban",
"J.",
""
],
[
"Vankova",
"G.",
""
]
] |
0705.2387 | Stepan G. Mashnik | A. N. Smirnov, O. I. Batenkov, V. P. Eismont, N. P. Filatov, J.
Blomgren, H. Conde, A. V. Prokofiev, S. G. Mashnik | Nucleon-induced fission cross-sections of tantalum and separated
tungsten isotopes and "compound nucleus" effect in intermediate energy region | 4 pages, 3 figures, 2 tables, only pdf file, to be published in Proc.
Int. Conf. on Nucl. Data for Sci. and Technology (ND2007), Nice, France,
April 22-27, 2007 | null | null | LA-UR-07-3200 | nucl-ex | null | Neutron- and proton-induced fission cross-sections of separated isotopes of
tungsten (182W, 183W, 184W, and 186W) and 181Ta relative to 209Bi have been
measured in the incident nucleon energy region 50 - 200 MeV using fission
chambers based on thin-film breakdown counters (TFBC) using quasi-monoenergetic
neutrons from the 7Li(p,n) reaction and at the proton beams of The Svedberg
Laboratory (TSL), Uppsala University (Uppsala, Sweden). The results are
compared with predictions by the CEM03.01 event generator, as well as with the
recent data for nuclei in the lead-bismuth region. The effect of "compound
nucleus" in the intermediate energy region is discussed, displaying in
exponential dependence of nucleon-induced fission cross-sections on the
parameter Z^2/A of the composite system (projectile+target nucleus), and in
other characteristics of the fission process for which parameter Z^2/A plays a
role similar to the one of the usual liquid-drop parameter Z^2/A of compound
nuclei.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:16:07 GMT"
},
{
"version": "v2",
"created": "Mon, 21 May 2007 17:16:28 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Smirnov",
"A. N.",
""
],
[
"Batenkov",
"O. I.",
""
],
[
"Eismont",
"V. P.",
""
],
[
"Filatov",
"N. P.",
""
],
[
"Blomgren",
"J.",
""
],
[
"Conde",
"H.",
""
],
[
"Prokofiev",
"A. V.",
""
],
[
"Mashnik",
"S. G.",
""
]
] |
0705.2388 | Carlo Rovelli | Jonathan Engle, Roberto Pereira, Carlo Rovelli | The loop-quantum-gravity vertex-amplitude | 6pages | Phys.Rev.Lett.99:161301,2007 | 10.1103/PhysRevLett.99.161301 | null | gr-qc | null | Spinfoam theories are hoped to provide the dynamics of non-perturbative loop
quantum gravity. But a number of their features remain elusive. The best
studied one -the euclidean Barrett-Crane model- does not have the boundary
state space needed for this, and there are recent indications that,
consequently, it may fail to yield the correct low-energy $n$-point functions.
These difficulties can be traced to the SO(4) -> SU(2) gauge fixing and the way
certain second class constraints are imposed, arguably incorrectly, strongly.
We present an alternative model, that can be derived as a bona fide
quantization of a Regge discretization of euclidean general relativity, and
where the constraints are imposed weakly. Its state space is a natural subspace
of the SO(4) spin-network space and matches the SO(3) hamiltonian spin network
space. The model provides a long sought SO(4)-covariant vertex amplitude for
loop quantum gravity.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:03:25 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Engle",
"Jonathan",
""
],
[
"Pereira",
"Roberto",
""
],
[
"Rovelli",
"Carlo",
""
]
] |
0705.2389 | Monika Jurkovic | M. Jurkovic, L. Szabados, J. Vink\'o, B. Cs\'ak | Pulsation and orbit of AU Pegasi | 4 pages, 10 figures | null | 10.1002/asna.200710814 | null | astro-ph | null | AU Pegasi is a pulsating star in a spectroscopic binary system with an
orbital period of 53.26 days. Between 1960 and 1990 an extremely rapid period
increase was observed in the value of the pulsation period, but in the last 15
years the observation show that the period set in 2.411 days. Fourier analysis
of photometric data obtained during the ASAS project and those taken at the
Piszkesteto Mountain Station of the Konkoly Observatory during 1994-2005
indicate that AU Pegasi is pulsating in two modes simultaneously, and the ratio
of the frequencies of the two modes is 0.706, a value common for double-mode
classical Cepheids. A careful analysis of other photometric observations
obtained during the era of the strong period increase also revealed existence
of a second mode. This may suggest that this star is not a Type II Cepheid,
despite its galactic position.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:29:31 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Jurkovic",
"M.",
""
],
[
"Szabados",
"L.",
""
],
[
"Vinkó",
"J.",
""
],
[
"Csák",
"B.",
""
]
] |
0705.2390 | Stuart Armstrong XV | Stuart Armstrong | Generalised Einstein condition and cone construction for parabolic
geometries | Newest version, with SO*(2m) included | null | null | null | math.DG math.AP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This paper attempts to define a generalisation of the standard Einstein
condition (in conformal/metric geometry) to any parabolic geometry. To do so,
it shows that any preserved involution $\sigma$ of the adjoint bundle $\mc{A}$
gives rise, given certain algebraic conditions, to a unique preferred affine
connection $\nabla$ with covariantly constant rho-tensor $\mathsf{P}$,
compatible with the algebraic bracket on $\mc{A}$. These conditions can
reasonably be considered the generalisations of the Einstein condition, and
recreate the standard Einstein condition in conformal geometry. The existence
of such an involution is implies by some simpler structures: preserved metrics
when the overall algebra $\mf{g}$ is $\mf{sl}(m,\mbb{F})$, preserved complex
structures anti-commuting with the skew-form for $\mf{g}=\mf{sp}(2m,\mbb{F})$,
and preserved subundles of the tangent bundle, of a certain rank, for all the
other non-exceptional simple Lie algebras. Examples of Einstein involutions are
constructed or referenced for several geometries. The existence of cone
constructions for certain Einstein involutions is then demonstrated.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:20:49 GMT"
},
{
"version": "v2",
"created": "Wed, 13 Jun 2007 17:54:11 GMT"
},
{
"version": "v3",
"created": "Mon, 18 Jun 2007 10:16:01 GMT"
},
{
"version": "v4",
"created": "Thu, 23 Aug 2007 16:39:54 GMT"
},
{
"version": "v5",
"created": "Thu, 14 Aug 2008 06:08:02 GMT"
}
] | 2008-08-14T00:00:00 | [
[
"Armstrong",
"Stuart",
""
]
] |
0705.2391 | Alexander Konovalov | V.A. Bovdi, A.B. Konovalov | Torsion units in integral group ring of Higman-Sims simple group | 10 pages | null | null | null | math.RA math.GR | null | Using the Luthar-Passi method, we investigate the classical Zassenhaus
conjecture for the normalized unit group of the integral group ring of the
Higman-Sims simple sporadic group HS. As a consequence, we confirm the
Kimmerle's conjecture on prime graphs for this sporadic group.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:09:58 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bovdi",
"V. A.",
""
],
[
"Konovalov",
"A. B.",
""
]
] |
0705.2392 | Andrea Guarino | Andrea Guarino, Gorazd Poberaj, Daniele Rezzonico, Riccardo
Degl'Innocenti and Peter Gunter | Electro-optically tunable microring resonators in lithium niobate | 15 pages, 8 figures | null | 10.1038/nphoton.2007.93 | null | physics.optics | null | Optical microresonators have recently attracted a growing attention in the
photonics community. Their applications range from quantum electro-dynamics to
sensors and filtering devices for optical telecommunication systems, where they
are likely to become an essential building block. The integration of nonlinear
and electro-optical properties in the resonators represents a very stimulating
challenge, as it would incorporate new and more advanced functionality. Lithium
niobate is an excellent candidate material, being an established choice for
electro-optic and nonlinear optical applications. Here we report on the first
realization of optical microring resonators in submicrometric thin films of
lithium niobate. The high index contrast films are produced by an improved
crystal ion slicing and bonding technique using benzocyclobutene. The rings
have radius R=100 um and their transmission spectrum has been tuned using the
electro-optic effect. These results open new perspectives for the use of
lithium niobate in chip-scale integrated optical devices and nonlinear optical
microcavities.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:11:31 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Guarino",
"Andrea",
""
],
[
"Poberaj",
"Gorazd",
""
],
[
"Rezzonico",
"Daniele",
""
],
[
"Degl'Innocenti",
"Riccardo",
""
],
[
"Gunter",
"Peter",
""
]
] |
0705.2393 | Simone De Liberato | Simone De Liberato | Observing the evolution of a quantum system that does not evolve | Two over three PRA referees didn't like the old title... And no more
quantum circuits in the new version | PRA 76, 042107 (2007) | 10.1103/PhysRevA.76.042107 | null | quant-ph | null | This article deals with the problem of gathering information on the time
evolution of a single metastable quantum system whose evolution is impeded by
the quantum Zeno effect. It has been found it is in principle possible to
obtain some information on the time evolution and, depending on the specific
system, even to measure its average decay rate, even if the system does not
undergo any evolution at all.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:28:15 GMT"
},
{
"version": "v2",
"created": "Wed, 22 Aug 2007 17:15:35 GMT"
}
] | 2013-05-29T00:00:00 | [
[
"De Liberato",
"Simone",
""
]
] |
0705.2394 | Roman Popovych | Vyacheslav Boyko, Jiri Patera and Roman O. Popovych | Invariants of triangular Lie algebras with one nilindependent diagonal
element | 11 pages; enhanced version | J. Phys. A 40 (2007), 9783-9792 | 10.1088/1751-8113/40/32/005 | null | math-ph math.MP math.RT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The invariants of solvable triangular Lie algebras with one nilindependent
diagonal element are studied exhaustively. Bases of the invariant sets of all
such algebras are constructed using an original algebraic algorithm based on
Cartan's method of moving frames and the special technique developed for
triangular and related algebras in [J. Phys. A: Math. Theor. 40 (2007),
7557-7572]. The conjecture of Tremblay and Winternitz [J. Phys. A: Math. Gen.
34 (2001), 9085-9099] on the number and form of elements in the bases is
completed and proved.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:28:31 GMT"
},
{
"version": "v2",
"created": "Wed, 25 Jul 2007 07:12:13 GMT"
},
{
"version": "v3",
"created": "Wed, 26 Sep 2007 08:00:22 GMT"
},
{
"version": "v4",
"created": "Sun, 1 Apr 2018 18:54:29 GMT"
}
] | 2018-04-03T00:00:00 | [
[
"Boyko",
"Vyacheslav",
""
],
[
"Patera",
"Jiri",
""
],
[
"Popovych",
"Roman O.",
""
]
] |
0705.2395 | Y. C. Huang (Yong-Chang Huang ) | Leng Liao (1), Yong-Chang Huang (1, 2)((1,2) Y. C. Huang, Institute of
Theoretical Physics, Beijing University of Technology (formerly Beijing
Polytechnic Univ.), Beijing, P. R. China, (2) CCAST (World Lab.), Beijing, P.
R. China) | Faddeev-Jackiw Quantization of the Gauge Invariant Self-dual Fields
Relative to String Theory | 8 pages | High Energy Phys.Nucl.Phys.30:191,2006 | null | null | hep-th | null | We obtain a new symplectic Lagrangian density and deduce Faddeev-Jackiw (FJ)
generalized brackets of the gauge invariant self-dual fields interacting with
gauge fields. We further give FJ quantization of this system. Furthermore, the
FJ method is compared with Dirac method, the results show the two methods are
equivalent in the quantization of this system. And by the practical research in
this letter, it can be found that the FJ method is really simpler than the
Dirac method, namely, the FJ method obviates the need to distinguish primary
and secondary constraints and first- and second-class constraints. Therefore,
the FJ method is a more economical and effective method of quantization.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:35:11 GMT"
}
] | 2010-01-08T00:00:00 | [
[
"Liao",
"Leng",
""
],
[
"Huang",
"Yong-Chang",
""
]
] |
0705.2396 | Andre Gsponer | Jean-Francois Colombeau, Andre Gsponer, Bernard Perrot | Nonlinear generalized functions and the Heisenberg-Pauli foundations of
Quantum Field Theory | 20 pages, research-expository paper, fully revised final version | null | null | ISRI-07-05 | math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In 1929 Heisenberg and Pauli laid the foundations of QFT by quantizing the
fields (method of canonical quantization). This general theory of quantized
fields has remained undisputed up to now. We show how the unmodified
Heisenberg-Pauli calculations make sense mathematically by using a theory of
generalized functions adapted to nonlinear operations. By providing an
appropriate mathematical setting, nonlinear generalized functions open doors
for their understanding but there remains presumably very hard technical
problems. (i) Domains of the interacting field operators: a priori the H-P
calculations give time dependent dense domains, what is not very convenient;
(ii) Calculations of the resulting matrix elements of the S operator: from the
unitarity of the S operator as a whole there are no longer ``infinities,'' but
a priori there is no other hope than heavy computer calculations; (iii)
Connection with renormalization theory: it should provide an approximation when
the coupling constant is small. The aim of this paper is to present, on the
grounds of a standard mathematical model of QFT (a self interacting scalar
boson field), a basis for improvement without significant prerequisites in
mathematics and physics. It is an attempt to use nonlinear generalized
functions in QFT, starting directly from the calculations made by physicists,
in the same way as they have already been used in classical mechanics and
general relativity.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 18:23:00 GMT"
},
{
"version": "v2",
"created": "Sat, 21 Jul 2007 17:04:06 GMT"
},
{
"version": "v3",
"created": "Thu, 3 Jul 2008 07:57:01 GMT"
}
] | 2008-07-03T00:00:00 | [
[
"Colombeau",
"Jean-Francois",
""
],
[
"Gsponer",
"Andre",
""
],
[
"Perrot",
"Bernard",
""
]
] |
0705.2397 | Aleksey Zinger | Aleksey Zinger | The Reduced Genus-One Gromov-Witten Invariants of Calabi-Yau
Hypersurfaces | 48 pages, 5 figures; exposition modified and a few typos corrected | null | null | null | math.AG math.SG | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the reduced genus 1 Gromov-Witten invariants of Calabi-Yau
hypersurfaces. As a consequence, we confirm the 1993 Bershadsky-Cecotti
Ooguri-Vafa (BCOV) prediction for the standard genus 1 GW-invariants of a
quintic threefold. We combine constructions from a series of previous papers
with the classical localization theorem to relate the reduced genus 1
invariants of a CY-hypersurface to previously computed integrals on moduli
spaces of stable genus 0 maps into projective space. The resulting, rather
unwieldy, expressions for a genus 1 equivariant generating function simplify
drastically, using a regularity property of a genus 0 equivariant generating
function in half of the cases. Finally, by disregarding terms that cannot
effect the non-equivariant part of the former, we relate the answer to an
explicit hypergeometric series in a simple way. The approach described in this
paper is systematic. It is directly applicable to computing reduced genus 1
GW-invariants of other complete intersections and should apply to higher-genus
localization computations.
| [
{
"version": "v1",
"created": "Wed, 16 May 2007 16:45:49 GMT"
},
{
"version": "v2",
"created": "Thu, 20 Sep 2007 12:03:17 GMT"
},
{
"version": "v3",
"created": "Tue, 23 Sep 2008 00:05:41 GMT"
}
] | 2008-09-23T00:00:00 | [
[
"Zinger",
"Aleksey",
""
]
] |
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