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list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0704.1801 | Harvey B. Meyer | Harvey B. Meyer | A calculation of the shear viscosity in SU(3) gluodynamics | 4 pages, 3 figures | Phys.Rev.D76:101701,2007 | 10.1103/PhysRevD.76.101701 | MIT-CTP 3830 | hep-lat hep-ph | null | We perform a lattice Monte-Carlo calculation of the two-point functions of
the energy-momentum tensor at finite temperature in the SU(3) gauge theory.
Unprecedented precision is obtained thanks to a multi-level algorithm. The
lattice operators are renormalized non-perturbatively and the classical
discretization errors affecting the correlators are corrected for. A robust
upper bound for the shear viscosity to entropy density ratio is derived, eta/s
< 1.0, and our best estimate is eta/s = 0.134(33) at T=1.65Tc under the
assumption of smoothness of the spectral function in the low-frequency region.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 17:17:51 GMT"
}
] | 2010-04-06T00:00:00 | [
[
"Meyer",
"Harvey B.",
""
]
] |
0704.1802 | Comelli Denis | Denis Comelli | A Way to Dynamically Overcome the Cosmological Constant Problem | 5 pages | Int.J.Mod.Phys.A23:4133-4143,2008 | 10.1142/S0217751X08041359 | null | gr-qc astro-ph | null | The Cosmological Constant problem can be solved once we require that the full
standard Einstein Hilbert lagrangian, gravity plus matter, is multiplied by a
total derivative. We analyze such a picture writing the total derivative as the
covariant gradient of a new vector field (b_mu). The dynamics of this b_mu
field can play a key role in the explanation of the present cosmological
acceleration of the Universe.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 17:29:06 GMT"
}
] | 2009-01-06T00:00:00 | [
[
"Comelli",
"Denis",
""
]
] |
0704.1803 | Andrew Toms | George A. Elliott, Andrew S. Toms | Regularity properties in the classification program for separable
amenable C*-algebras | 19 pages, to appear in Bull. AMS, April 2008 | null | null | null | math.OA math.FA | null | We report on recent progress in the program to classify separable amenable
C*-algebras. Our emphasis is on the newly apparent role of regularity
properties such as finite decomposition rank, strict comparison of positive
elements, and Z-stability, and on the importance of the Cuntz semigroup. We
include a brief history of the program's successes since 1989, a more detailed
look at the Villadsen-type algebras which have so dramatically changed the
landscape, and a collection of announcements on the structure and properties of
the Cuntz semigroup.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 17:45:01 GMT"
},
{
"version": "v2",
"created": "Sun, 15 Apr 2007 14:56:01 GMT"
},
{
"version": "v3",
"created": "Wed, 22 Aug 2007 20:32:23 GMT"
}
] | 2007-08-22T00:00:00 | [
[
"Elliott",
"George A.",
""
],
[
"Toms",
"Andrew S.",
""
]
] |
0704.1804 | Ryan Kalas | Ryan M. Kalas, D. Blume | Equation of state of atomic systems beyond s-wave determined by the
lowest order constrained variational method: Large scattering length limit | 10 pages, 7 figures | null | null | null | cond-mat.other | null | Dilute Fermi systems with large s-wave scattering length a_s exhibit
universal properties if the interparticle spacing r_o greatly exceeds the range
of the underlying two-body interaction potential. In this regime, r_o is the
only relevant length scale and observables such as the energy per particle
depend only on r_o (or, equivalently, the energy E_{FG} of the free Fermi gas).
This paper investigates Bose and Fermi systems with non-vanishing angular
momentum l using the lowest order constrained variational method. We focus on
the regime where the generalized scattering length becomes large and determine
the relevant length scales. For Bose gases with large generalized scattering
lengths, we obtain simple expressions for the energy per particle in terms of a
l-dependent length scale \xi_l, which depends on the range of the underlying
two-body potential and the average interparticle spacing. We discuss possible
implications for dilute two-component Fermi systems with finite l. Furthermore,
we determine the equation of state of liquid and gaseous bosonic helium.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 18:09:58 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kalas",
"Ryan M.",
""
],
[
"Blume",
"D.",
""
]
] |
0704.1805 | Youngone Lee | Youngone Lee | On Charge Conservation and The Equivalence Principle in the
Noncommutative Spacetime | typos corrected, references added, accepted for publication in Phys.
Rev. D | Phys.Rev.D76:025022,2007 | 10.1103/PhysRevD.76.025022 | null | hep-th | null | We investigate one of the consequences of the twisted Poincare symmetry. We
derive the charge conservation law and show that the equivalence principle is
satisfied in the canonical noncommutative spacetime. We applied the twisted
Poincare symmetry to the Weinberg's analysis. To this end, we generalize our
earlier construction of the twisted S matrix \cite{Bu}, which apply the
noncommutativity to the fourier modes, to the massless fields of integer spins.
The transformation formula for the twisted S matrix for the massless fields of
integer spin has been obtained. For massless fields of spin 1, we obtain the
conservation of charge, and the universality of coupling constant for massless
fields of spin 2, which can be interpreted as the equality of gravitational
mass and inertial mass, i.e., the equivalence principle.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 18:19:07 GMT"
},
{
"version": "v2",
"created": "Sun, 22 Apr 2007 09:00:23 GMT"
},
{
"version": "v3",
"created": "Wed, 20 Jun 2007 01:07:56 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Lee",
"Youngone",
""
]
] |
0704.1806 | Stephen Teitel | Peter Olsson and S. Teitel | Critical Scaling of Shear Viscosity at the Jamming Transition | replaced with published version; new references added | Phys. Rev. Lett. 99, 178001 (2007) | 10.1103/PhysRevLett.99.178001 | null | cond-mat.soft cond-mat.stat-mech | null | We carry out numerical simulations to study transport behavior about the
jamming transition of a model granular material in two dimensions at zero
temperature. Shear viscosity \eta is computed as a function of particle volume
density \rho and applied shear stress \sigma, for diffusively moving particles
with a soft core interaction. We find an excellent scaling collapse of our data
as a function of the scaling variable \sigma/|\rho_c-\rho|^\Delta, where \rho_c
is the critical density at \sigma=0 ("point J"), and \Delta is the crossover
scaling critical exponent. Our results show that jamming is a true critical
phenomenon, extending to driven steady states along the non-equilibrium \sigma
axis of the \rho-\sigma phase diagram.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 19:10:26 GMT"
},
{
"version": "v2",
"created": "Fri, 26 Oct 2007 20:04:40 GMT"
}
] | 2011-11-09T00:00:00 | [
[
"Olsson",
"Peter",
""
],
[
"Teitel",
"S.",
""
]
] |
0704.1807 | Ruy Tojeiro | Ion Moutinho and Ruy Tojeiro | Polar actions on compact Euclidean hypersurfaces | 17 pages | null | null | null | math.DG | null | Given an isometric immersion $f\colon M^n\to \R^{n+1}$ of a compact
Riemannian manifold of dimension $n\geq 3$ into Euclidean space of dimension
$n+1$, we prove that the identity component $Iso^0(M^n)$ of the isometry group
$Iso(M^n)$ of $M^n$ admits an orthogonal representation $\Phi\colon
Iso^0(M^n)\to SO(n+1)$ such that $f\circ g=\Phi(g)\circ f$ for every $g\in
Iso^0(M^n)$. If $G$ is a closed connected subgroup of $Iso(M^n)$ acting locally
polarly on $M^n$, we prove that $\Phi(G)$ acts polarly on $\R^{n+1}$, and we
obtain that $f(M^n)$ is given as $\Phi(G)(L)$, where $L$ is a hypersurface of a
section which is invariant under the Weyl group of the $\Phi(G)$-action. We
also find several sufficient conditions for such an $f$ to be a rotation
hypersurface. Finally, we show that compact Euclidean rotation hypersurfaces of
dimension $n\geq 3$ are characterized by their underlying warped product
structure.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 19:45:57 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Moutinho",
"Ion",
""
],
[
"Tojeiro",
"Ruy",
""
]
] |
0704.1808 | Neil J. Cornish | Neil J. Cornish and Tyson B. Littenberg | Tests of Bayesian Model Selection Techniques for Gravitational Wave
Astronomy | 11 pages, 6 figures | Phys.Rev.D76:083006,2007 | 10.1103/PhysRevD.76.083006 | null | gr-qc | null | The analysis of gravitational wave data involves many model selection
problems. The most important example is the detection problem of selecting
between the data being consistent with instrument noise alone, or instrument
noise and a gravitational wave signal. The analysis of data from ground based
gravitational wave detectors is mostly conducted using classical statistics,
and methods such as the Neyman-Pearson criteria are used for model selection.
Future space based detectors, such as the \emph{Laser Interferometer Space
Antenna} (LISA), are expected to produced rich data streams containing the
signals from many millions of sources. Determining the number of sources that
are resolvable, and the most appropriate description of each source poses a
challenging model selection problem that may best be addressed in a Bayesian
framework. An important class of LISA sources are the millions of low-mass
binary systems within our own galaxy, tens of thousands of which will be
detectable. Not only are the number of sources unknown, but so are the number
of parameters required to model the waveforms. For example, a significant
subset of the resolvable galactic binaries will exhibit orbital frequency
evolution, while a smaller number will have measurable eccentricity. In the
Bayesian approach to model selection one needs to compute the Bayes factor
between competing models. Here we explore various methods for computing Bayes
factors in the context of determining which galactic binaries have measurable
frequency evolution. The methods explored include a Reverse Jump Markov Chain
Monte Carlo (RJMCMC) algorithm, Savage-Dickie density ratios, the Schwarz-Bayes
Information Criterion (BIC), and the Laplace approximation to the model
evidence. We find good agreement between all of the approaches.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 19:47:48 GMT"
},
{
"version": "v2",
"created": "Sun, 15 Apr 2007 05:54:09 GMT"
},
{
"version": "v3",
"created": "Thu, 8 Nov 2007 18:41:40 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Cornish",
"Neil J.",
""
],
[
"Littenberg",
"Tyson B.",
""
]
] |
0704.1809 | Marek Zukowski | Piotr Badziag and Marek Zukowski | All tight multipartite Bell correlation inequalities for an arbitrary
number of dichotomic observables per observer | there is a mistake in the proof, and even worse... one can find a
counterexample | null | null | null | quant-ph | null | Derivation of the full set of Bell inequalities involving correlation
functions, for two parties, with binary observables, and N possible local
settings is not as easy as it seemed. The proof of v1 is wrong. Additionaly one
can find a counterexample, which will be presented soon. Thus our thesis is
dead. Still the series of Bell inequalities discussed in the manuscript (v1)
form a necessary condition for local realism, and are tight. They are tight and
complete (sufficient) only for N=3 settings per observer (as shown in
quant-ph/0611086, fortunately using an entirely different approach).
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 19:49:17 GMT"
},
{
"version": "v2",
"created": "Sat, 26 May 2007 17:04:32 GMT"
}
] | 2007-06-13T00:00:00 | [
[
"Badziag",
"Piotr",
""
],
[
"Zukowski",
"Marek",
""
]
] |
0704.1810 | Jeffrey N. Cuzzi | Robert C. Hogan and Jeffrey N. Cuzzi | A Cascade Model for Particle Concentration and Enstrophy in Fully
Developed Turbulence with Mass Loading Feedback | Accepted by Phys. Rev. E; in press; 9 pages, 8 figures; the research
is relevant to turbulent concentration of chondrules and other small
particles in protoplanetary nebulae. Solid/gas mass ratios as large as 100
are possible before turbulence is damped, for particles in this size range | Phys.Rev.E75:056305,2007 | 10.1103/PhysRevE.75.056305 | null | astro-ph | null | A cascade model is described based on multiplier distributions determined
from 3D direct numerical simulations (DNS) of turbulent particle laden flows,
which include two-way coupling between the phases at global mass loadings equal
to unity. The governing Eulerian equations are solved using pseudo-spectral
methods on up to 512**3 computional grid points. DNS results for particle
concentration and enstrophy at Taylor microscale Reynolds numbers in the range
34 - 170 were used to directly determine multiplier distributions (PDFs) on
spatial scales 3 times the Kolmogorov length scale. The width of the PDFs,
which is a measure of intermittency, decreases with increasing mass loading
within the local region where the multipliers are measured. The functional form
of this dependence is not sensitive to Reynolds numbers in the range
considered. A partition correlation probability is included in the cascade
model to account for the observed spatial anticorrelation between particle
concentration and enstrophy. Joint probability distribution functions of
concentration and enstrophy generated using the cascade model are shown to be
in excellent agreement with those derived directly from our 3D simulations.
Probabilities predicted by the cascade model are presented at Reynolds numbers
well beyond what is achievable by direct simulation. These results clearly
indicate that particle mass loading significantly reduces the probabilities of
high particle concentration and enstrophy relative to those resulting from
unloaded runs. Particle mass density appears to reach a limit at around 100
times the gas density. This approach has promise for significant computational
savings in certain applications.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 19:51:16 GMT"
},
{
"version": "v2",
"created": "Fri, 13 Apr 2007 20:02:05 GMT"
}
] | 2015-06-30T00:00:00 | [
[
"Hogan",
"Robert C.",
""
],
[
"Cuzzi",
"Jeffrey N.",
""
]
] |
0704.1811 | Samarth Swarup | Samarth Swarup and Les Gasser | Unifying Evolutionary and Network Dynamics | 11 pages, 12 figures, Accepted for publication in Physical Review E | null | 10.1103/PhysRevE.75.066114 | null | q-bio.QM q-bio.PE | null | Many important real-world networks manifest "small-world" properties such as
scale-free degree distributions, small diameters, and clustering. The most
common model of growth for these networks is "preferential attachment", where
nodes acquire new links with probability proportional to the number of links
they already have. We show that preferential attachment is a special case of
the process of molecular evolution. We present a new single-parameter model of
network growth that unifies varieties of preferential attachment with the
quasispecies equation (which models molecular evolution), and also with the
Erdos-Renyi random graph model. We suggest some properties of evolutionary
models that might be applied to the study of networks. We also derive the form
of the degree distribution resulting from our algorithm, and we show through
simulations that the process also models aspects of network growth. The
unification allows mathematical machinery developed for evolutionary dynamics
to be applied in the study of network dynamics, and vice versa.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 19:56:37 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Swarup",
"Samarth",
""
],
[
"Gasser",
"Les",
""
]
] |
0704.1812 | Nicholas Law | N.M. Law (1 and 2), S.T. Hodgkin (2), C.D. Mackay (2) ((1) Caltech,
(2) IOA, Cambridge) | The LuckyCam Survey for Very Low Mass Binaries II: 13 new M4.5-M6.0
Binaries | 11 pages, 8 figures. Submitted to MNRAS | null | 10.1111/j.1365-2966.2007.12675.x | null | astro-ph | null | We present results from a high-angular-resolution survey of 78 very low mass
(VLM) binary systems with 6.0 <= V-K colour <= 7.5 and proper motion >= 0.15
arcsec/yr. 21 VLM binaries were detected, 13 of them new discoveries. The new
binary systems range in separation between 0.18 arcsec and 1.3 arcsec. The
distance-corrected binary fraction is 13.5% (+6.5%/-4%), in agreement with
previous results. 9 of the new binary systems have orbital radii > 10 AU,
including a new wide VLM binary with 27 AU projected orbital separation. One of
the new systems forms two components of a 2300 AU separation triple system. We
find that the orbital radius distribution of the binaries with V-K < 6.5 in
this survey appears to be different from that of redder (lower-mass) objects,
suggesting a possible rapid change in the orbital radius distribution at around
the M5 spectral type. The target sample was also selected to investigate X-ray
activity among VLM binaries. There is no detectable correlation between excess
X-Ray emission and the frequency and binary properties of the VLM systems.
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 05:09:45 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Law",
"N. M.",
"",
"1 and 2"
],
[
"Hodgkin",
"S. T.",
""
],
[
"Mackay",
"C. D.",
""
]
] |
0704.1813 | Mukremin Kilic | Mukremin Kilic, Warren R. Brown, Carlos Allende Prieto, M. H.
Pinsonneault, and S. J. Kenyon | The Discovery of a Companion to the Lowest Mass White Dwarf | ApJ, in press. See the Press Release at
http://www.cfa.harvard.edu/press/2007/pr200708.html | Astrophys.J.664:1088-1092,2007 | 10.1086/518735 | null | astro-ph | null | We report the detection of a radial velocity companion to SDSS
J091709.55+463821.8, the lowest mass white dwarf currently known with
M~0.17Msun. The radial velocity of the white dwarf shows variations with a
semi-amplitude of 148.8 km/s and a period of 7.5936 hours, which implies a
companion mass of M > 0.28Msun. The lack of evidence of a companion in the
optical photometry forces any main-sequence companion to be smaller than
0.1Msun, hence a low mass main sequence star companion is ruled out for this
system. The companion is most likely another white dwarf, and we present
tentative evidence for an evolutionary scenario which could have produced it.
However, a neutron star companion cannot be ruled out and follow-up radio
observations are required to search for a pulsar companion.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 20:06:53 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Kilic",
"Mukremin",
""
],
[
"Brown",
"Warren R.",
""
],
[
"Prieto",
"Carlos Allende",
""
],
[
"Pinsonneault",
"M. H.",
""
],
[
"Kenyon",
"S. J.",
""
]
] |
0704.1814 | Giovanni Villadoro | Nima Arkani-Hamed, Sergei Dubovsky, Alberto Nicolis, Enrico
Trincherini, Giovanni Villadoro | A Measure of de Sitter Entropy and Eternal Inflation | 33 pages, 8 figures | JHEP 0705:055,2007 | 10.1088/1126-6708/2007/05/055 | null | hep-th | null | We show that in any model of non-eternal inflation satisfying the null energy
condition, the area of the de Sitter horizon increases by at least one Planck
unit in each inflationary e-folding. This observation gives an operational
meaning to the finiteness of the entropy S_dS of an inflationary de Sitter
space eventually exiting into an asymptotically flat region: the asymptotic
observer is never able to measure more than e^(S_dS) independent inflationary
modes. This suggests a limitation on the amount of de Sitter space outside the
horizon that can be consistently described at the semiclassical level, fitting
well with other examples of the breakdown of locality in quantum gravity, such
as in black hole evaporation. The bound does not hold in models of inflation
that violate the null energy condition, such as ghost inflation. This
strengthens the case for the thermodynamical interpretation of the bound as
conventional black hole thermodynamics also fails in these models, strongly
suggesting that these theories are incompatible with basic gravitational
principles.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 20:08:20 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Arkani-Hamed",
"Nima",
""
],
[
"Dubovsky",
"Sergei",
""
],
[
"Nicolis",
"Alberto",
""
],
[
"Trincherini",
"Enrico",
""
],
[
"Villadoro",
"Giovanni",
""
]
] |
0704.1815 | Daniel E. Sheehy | Daniel E. Sheehy (Louisiana State University) and Joerg Schmalian
(Iowa State University) | Kondo-lattice screening in a d-wave superconductor | 11 pages, 6 figures, revised version to appear in Physical Review B | Phys. Rev. B 77, 125129 (2008). | 10.1103/PhysRevB.77.125129 | null | cond-mat.str-el | null | We show that local moment screening in a Kondo lattice with d-wave
superconducting conduction electrons is qualitatively different from the
corresponding single Kondo impurity case. Despite the conduction-electron
pseudogap, Kondo-lattice screening is stable if the gap amplitude obeys $\Delta
<\sqrt{\tk D}$, in contrast to the single impurity condition $\Delta <\tk$
(where $\tk$ is the Kondo temperature for $\Delta = 0$ and D is the bandwidth).
Our theory explains the heavy electron behavior in the d-wave superconductor
Nd_{2-x}Ce_{x}CuO_{4}.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 22:54:39 GMT"
},
{
"version": "v2",
"created": "Fri, 27 Jul 2007 17:21:19 GMT"
},
{
"version": "v3",
"created": "Thu, 31 Jan 2008 23:18:57 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Sheehy",
"Daniel E.",
"",
"Louisiana State University"
],
[
"Schmalian",
"Joerg",
"",
"Iowa State University"
]
] |
0704.1816 | Sara L. Ellison | Sara L. Ellison, Joseph F. Hennawi, Crystal L. Martin, Jesper
Sommer-Larsen | Coincident, 100 kpc-scale damped Lyman alpha absorption towards a binary
QSO: how large are galaxies at z ~ 3? | Accepted for publication in MNRAS. Full resolution simulation images
available in pdf copy of the manuscript at
http://www.astro.uvic.ca/~sara/1116.pdf | Mon.Not.Roy.Astron.Soc.378:801-818,2007 | 10.1111/j.1365-2966.2007.11847.x | null | astro-ph | null | We report coincident damped Lyman alpha (DLA) and sub-DLA absorption at z =
2.66 and z = 2.94 towards the z ~ 3 13.8 arcsecond separation binary quasar
SDSS 1116+4118 AB. At the redshifts of the absorbers, this angular separation
corresponds to a proper transverse separation of ~ 110 kpc. A third absorber, a
sub-DLA at z = 2.47, is detected towards SDSS 1116+4118 B, but no corresponding
high column density absorber is present towards SDSS 1116+4118 A. We use high
resolution galaxy simulations and a clustering analysis to interpret the
coincident absorption and its implications for galaxy structure at z ~ 3. We
conclude that the common absorption in the two lines of sight is unlikely to
arise from a single galaxy, or a galaxy plus satellite system, and is more
feasibly explained by a group of two or more galaxies with separations ~ 100
kpc. The impact of these findings on single line of sight observations is also
discussed; we show that abundances of DLAs may be affected by up to a few
tenths of a dex by line of sight DLA blending. From a Keck ESI spectrum of the
two quasars, we measure metal column densities for all five absorbers and
determine abundances for the three absorbers with log N(HI) > 20. For the two
highest N(HI) absorbers, we determine high levels of metal enrichment,
corresponding to 1/3 and 1/5 solar. These metallicities are amongst the highest
measured for DLAs at any redshift and are consistent with values measured in
Lyman break galaxies at 2 < z < 3. For the DLA at z = 2.94 we also infer an
approximately solar ratio of alpha-to-Fe peak elements from [S/Zn] = +0.05, and
measure an upper limit for the molecular fraction in this particular line of
sight of log f(H_2)< -5.5.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 20:15:36 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Ellison",
"Sara L.",
""
],
[
"Hennawi",
"Joseph F.",
""
],
[
"Martin",
"Crystal L.",
""
],
[
"Sommer-Larsen",
"Jesper",
""
]
] |
0704.1817 | Louis Strigari | Louis E. Strigari, James S. Bullock, Manoj Kaplinghat, Juerg Diemand,
Michael Kuhlen, Piero Madau | Redefining the Missing Satellites Problem | 8 pages, 6 figures | Astrophys.J.669:676-683,2007 | 10.1086/521914 | null | astro-ph | null | Numerical simulations of Milky-Way size Cold Dark Matter (CDM) halos predict
a steeply rising mass function of small dark matter subhalos and a substructure
count that greatly outnumbers the observed satellites of the Milky Way. Several
proposed explanations exist, but detailed comparison between theory and
observation in terms of the maximum circular velocity (Vmax) of the subhalos is
hampered by the fact that Vmax for satellite halos is poorly constrained. We
present comprehensive mass models for the well-known Milky Way dwarf
satellites, and derive likelihood functions to show that their masses within
0.6 kpc (M_0.6) are strongly constrained by the present data. We show that the
M_0.6 mass function of luminous satellite halos is flat between ~ 10^7 and 10^8
M_\odot. We use the ``Via Lactea'' N-body simulation to show that the M_0.6
mass function of CDM subhalos is steeply rising over this range. We rule out
the hypothesis that the 11 well-known satellites of the Milky Way are hosted by
the 11 most massive subhalos. We show that models where the brightest
satellites correspond to the earliest forming subhalos or the most massive
accreted objects both reproduce the observed mass function. A similar analysis
with the newly-discovered dwarf satellites will further test these scenarios
and provide powerful constraints on the CDM small-scale power spectrum and warm
dark matter models.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 20:24:31 GMT"
},
{
"version": "v2",
"created": "Wed, 24 Oct 2007 18:46:30 GMT"
}
] | 2010-11-11T00:00:00 | [
[
"Strigari",
"Louis E.",
""
],
[
"Bullock",
"James S.",
""
],
[
"Kaplinghat",
"Manoj",
""
],
[
"Diemand",
"Juerg",
""
],
[
"Kuhlen",
"Michael",
""
],
[
"Madau",
"Piero",
""
]
] |
0704.1818 | Martin Wainwright | Martin J. Wainwright, Emin Martinian | Low-density graph codes that are optimal for source/channel coding and
binning | Appeared as technical report 730, Dept. of Statistics, UC Berkeley.
Portions previously published in conference form (DCC 2006; ISIT 2006) | null | null | Technical report 730 | cs.IT math.IT | null | We describe and analyze the joint source/channel coding properties of a class
of sparse graphical codes based on compounding a low-density generator matrix
(LDGM) code with a low-density parity check (LDPC) code. Our first pair of
theorems establish that there exist codes from this ensemble, with all degrees
remaining bounded independently of block length, that are simultaneously
optimal as both source and channel codes when encoding and decoding are
performed optimally. More precisely, in the context of lossy compression, we
prove that finite degree constructions can achieve any pair $(R, D)$ on the
rate-distortion curve of the binary symmetric source. In the context of channel
coding, we prove that finite degree codes can achieve any pair $(C, p)$ on the
capacity-noise curve of the binary symmetric channel. Next, we show that our
compound construction has a nested structure that can be exploited to achieve
the Wyner-Ziv bound for source coding with side information (SCSI), as well as
the Gelfand-Pinsker bound for channel coding with side information (CCSI).
Although the current results are based on optimal encoding and decoding, the
proposed graphical codes have sparse structure and high girth that renders them
well-suited to message-passing and other efficient decoding procedures.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 20:33:43 GMT"
}
] | 2007-07-13T00:00:00 | [
[
"Wainwright",
"Martin J.",
""
],
[
"Martinian",
"Emin",
""
]
] |
0704.1819 | Yuji Tachikawa | Kentaro Hanaki, Keisuke Ohashi and Yuji Tachikawa | Comments on Charges and Near-Horizon Data of Black Rings | 30 pages, 1 figure; v2: additional references; v3: published version | JHEP0712:057,2007 | 10.1088/1126-6708/2007/12/057 | TIT/HEP-570 | hep-th | null | We study how the charges of the black rings measured at the asymptotic
infinity are encoded in the near-horizon metric and gauge potentials,
independent of the detailed structure of the connecting region. Our analysis
clarifies how different sets of four-dimensional charges can be assigned to a
single five-dimensional object under the Kaluza-Klein reduction. Possible
choices are related by the Witten effect on dyons and by the large gauge
transformation in four and five dimensions, respectively.
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 13:59:57 GMT"
},
{
"version": "v2",
"created": "Mon, 30 Apr 2007 20:37:19 GMT"
},
{
"version": "v3",
"created": "Mon, 17 Dec 2007 16:16:52 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Hanaki",
"Kentaro",
""
],
[
"Ohashi",
"Keisuke",
""
],
[
"Tachikawa",
"Yuji",
""
]
] |
0704.1820 | Oriol T. Valls | Klaus Halterman, Paul H. Barsic, and Oriol T. Valls | Odd Triplet Pairing in clean Superconductor/Ferromagnet heterostructures | Four pages, including four figures | Phys. Rev Lett. 99, 127002 (2007) | 10.1103/PhysRevLett.99.127002 | null | cond-mat.supr-con | null | We study triplet pairing correlations in clean Ferromagnet (F)/Superconductor
(S) nanojunctions, via fully self consistent solution of the Bogoliubov-de
Gennes equations. We consider FSF trilayers, with S being an s-wave
superconductor, and an arbitrary angle $\alpha$ between the magnetizations of
the two F layers. We find that contrary to some previous expectations, triplet
correlations, odd in time, are induced in both the S and F layers in the clean
limit. We investigate their behavior as a function of time, position, and
$\alpha$. The triplet amplitudes are largest at times on the order of the
inverse ``Debye'' frequency, and at that time scale they are long ranged in
both S and F. The zero temperature condensation energy is found to be lowest
when the magnetizations are antiparallel.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 21:47:43 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Halterman",
"Klaus",
""
],
[
"Barsic",
"Paul H.",
""
],
[
"Valls",
"Oriol T.",
""
]
] |
0704.1821 | Matthew Reece | Kaustubh Agashe, Csaba Csaki, Christophe Grojean, Matthew Reece | The S-parameter in Holographic Technicolor Models | 21 pages, 2 figures. v2: references added | JHEP 0712:003,2007 | 10.1088/1126-6708/2007/12/003 | null | hep-ph | null | We study the S parameter, considering especially its sign, in models of
electroweak symmetry breaking (EWSB) in extra dimensions, with fermions
localized near the UV brane. Such models are conjectured to be dual to 4D
strong dynamics triggering EWSB. The motivation for such a study is that a
negative value of S can significantly ameliorate the constraints from
electroweak precision data on these models, allowing lower mass scales (TeV or
below) for the new particles and leading to easier discovery at the LHC. We
first extend an earlier proof of S>0 for EWSB by boundary conditions in
arbitrary metric to the case of general kinetic functions for the gauge fields
or arbitrary kinetic mixing. We then consider EWSB in the bulk by a Higgs VEV
showing that S is positive for arbitrary metric and Higgs profile, assuming
that the effects from higher-dimensional operators in the 5D theory are
sub-leading and can therefore be neglected. For the specific case of AdS_5 with
a power law Higgs profile, we also show that S ~ + O(1), including effects of
possible kinetic mixing from higher-dimensional operator (of NDA size) in the
$5D$ theory. Therefore, our work strongly suggests that S is positive in
calculable models in extra dimensions.
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 15:43:51 GMT"
},
{
"version": "v2",
"created": "Wed, 25 Jul 2007 10:15:21 GMT"
}
] | 2009-01-06T00:00:00 | [
[
"Agashe",
"Kaustubh",
""
],
[
"Csaki",
"Csaba",
""
],
[
"Grojean",
"Christophe",
""
],
[
"Reece",
"Matthew",
""
]
] |
0704.1822 | Zuoliang Hou | Zuoliang Hou and Qi Li | Energy Functionals for the Parabolic Monge-Ampere Equation | 12 pages | null | null | null | math.AP math.DG | null | We introduce certain energy functionals to the complex Monge-Ampere equation
over a bounded domain with inhomogeneous boundary condition, and use these
functionals to show the convergence of the solution to the parabolic
Monge-Ampere equation.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 20:39:33 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hou",
"Zuoliang",
""
],
[
"Li",
"Qi",
""
]
] |
0704.1823 | Alejandro Adem | Alejandro Adem, Jianquan Ge, Jianzhong Pan and Nansen Petrosyan | Compatible Actions and Cohomology of Crystallographic Groups | null | null | null | null | math.AT math.GR | null | We compute the cohomology of crystallographic groups with holonomy of prime
order. As an application we compute the group of gerbes associated to many
six--dimensional toroidal orbifolds arising in string theory.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 20:41:10 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Adem",
"Alejandro",
""
],
[
"Ge",
"Jianquan",
""
],
[
"Pan",
"Jianzhong",
""
],
[
"Petrosyan",
"Nansen",
""
]
] |
0704.1824 | Yaozhong Hu | Yaozhong Hu, David Nualart | Stochastic Heat Equation Driven by Fractional Noise and Local Time | null | null | null | null | math.PR math.AP | null | The aim of this paper is to study the $d$-dimensional stochastic heat
equation with a multiplicative Gaussian noise which is white in space and it
has the covariance of a fractional Brownian motion with Hurst parameter $% H\in
(0,1)$ in time. Two types of equations are considered. First we consider the
equation in the It\^{o}-Skorohod sense, and later in the Stratonovich sense. An
explicit chaos development for the solution is obtained. On the other hand, the
moments of the solution are expressed in terms of the exponential moments of
some weighted intersection local time of the Brownian motion.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 20:48:34 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hu",
"Yaozhong",
""
],
[
"Nualart",
"David",
""
]
] |
0704.1825 | Antoine Merand | A. M\'erand, J. Audenberg, P. Kervella, V. Coud\'e du Foresto, T. ten
Brummelaar, H. McAlister, et al | Extended envelopes around Galactic Cepheids III. Y Oph and alpha Per
from near-infrared interferometry with CHARA/FLUOR | accepted for publication in ApJ | Astrophys.J.664:1093-1101,2007 | 10.1086/518597 | null | astro-ph | null | Unbiased angular diameter measurements are required for accurate distances to
Cepheids using the interferometric Baade Wesselink method (IBWM). The precision
of this technique is currently limited by interferometric measurements at the
1.5% level. At this level, the center-to-limb darkening (CLD) and the presence
of circumstellar envelopes (CSE) seem to be the two main sources of bias. The
observations we performed aim at improving our knowledge of the interferometric
visibility profile of Cepheids. In particular, we assess the systematic
presence of CSE around Cepheids in order determine accurate distances with the
IBWM free from CSE biased angular diameters. We observed a Cepheid (Y Oph) for
which the pulsation is well resolved and a non-pulsating yellow supergiant
(alpha Per) using long-baseline near-infrared interferometry. We interpreted
these data using a simple CSE model we previously developed. We found that our
observations of alpha Per do not provide evidence for a CSE. The measured CLD
is explained by an hydrostatic photospheric model. Our observations of Y Oph,
when compared to smaller baseline measurements, suggest that it is surrounded
by a CSE with similar characteristics to CSE found previously around other
Cepheids. We have determined the distance to Y Oph to be d=491+/-18 pc.
Additional evidence points toward the conclusion that most Cepheids are
surrounded by faint CSE, detected by near infrared interferometry: after
observing four Cepheids, all show evidence for a CSE. Our CSE non-detection
around a non-pulsating supergiant in the instability strip, alpha Per, provides
confidence in the detection technique and suggests a pulsation driven mass-loss
mechanism for the Cepheids.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 21:39:59 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Mérand",
"A.",
""
],
[
"Audenberg",
"J.",
""
],
[
"Kervella",
"P.",
""
],
[
"Foresto",
"V. Coudé du",
""
],
[
"Brummelaar",
"T. ten",
""
],
[
"McAlister",
"H.",
""
]
] |
0704.1826 | Michael Klasen | G. Bozzi (ITP Karlsruhe), B. Fuks, B. Herrmann, M. Klasen (LPSC
Grenoble) | Squark and Gaugino Hadroproduction and Decays in Non-Minimal Flavour
Violating Supersymmetry | 35 pages, 29 (partly colour) figures. Some typos corrected, wording
of several paragraphs improved, version accepted by Nucl. Phys. B | Nucl.Phys.B787:1-54,2007 | 10.1016/j.nuclphysb.2007.05.031 | KA-TP-07-2007, LPSC 07-023, SFB/CPP-07-09 | hep-ph | null | We present an extensive analysis of squark and gaugino hadroproduction and
decays in non-minimal flavour violating supersymmetry. We employ the so-called
super-CKM basis to define the possible misalignment of quark and squark
rotations, and we use generalized (possibly complex) charges to define the
mutual couplings of (s)quarks and gauge bosons/gauginos. The cross sections for
all squark-(anti-)squark/gaugino pair and squark-gaugino associated production
processes as well as their decay widths are then given in compact analytic
form. For four different constrained supersymmetry breaking models with
non-minimal flavour violation in the second/third generation squark sector
only, we establish the parameter space regions allowed/favoured by low-energy,
electroweak precision, and cosmological constraints and display the chirality
and flavour decomposition of all up- and down-type squark mass eigenstates.
Finally, we compute numerically the dependence of a representative sample of
production cross sections at the LHC on the off-diagonal mass matrix elements
in the experimentally allowed/favoured ranges.
| [
{
"version": "v1",
"created": "Tue, 10 Apr 2007 11:39:10 GMT"
},
{
"version": "v2",
"created": "Fri, 1 Jun 2007 13:39:42 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bozzi",
"G.",
"",
"ITP Karlsruhe"
],
[
"Fuks",
"B.",
"",
"LPSC\n Grenoble"
],
[
"Herrmann",
"B.",
"",
"LPSC\n Grenoble"
],
[
"Klasen",
"M.",
"",
"LPSC\n Grenoble"
]
] |
0704.1827 | Gerald Krafft | Gerald Krafft | Transaction-Oriented Simulation In Ad Hoc Grids | 101 pages (plus 131 appendix), 23 figures, 11 tables, MSc thesis for
degree in Advanced Computer Science at the Westminster University, London | null | null | null | cs.DC | null | This paper analyses the possibilities of performing parallel
transaction-oriented simulations with a special focus on the space-parallel
approach and discrete event simulation synchronisation algorithms that are
suitable for transaction-oriented simulation and the target environment of Ad
Hoc Grids. To demonstrate the findings a Java-based parallel
transaction-oriented simulator for the simulation language GPSS/H is
implemented on the basis of the promising Shock Resistant Time Warp
synchronisation algorithm and using the Grid framework ProActive. The
validation of this parallel simulator shows that the Shock Resistant Time Warp
algorithm can successfully reduce the number of rolled back Transaction moves
but it also reveals circumstances in which the Shock Resistant Time Warp
algorithm can be outperformed by the normal Time Warp algorithm. The conclusion
of this paper suggests possible improvements to the Shock Resistant Time Warp
algorithm to avoid such problems.
| [
{
"version": "v1",
"created": "Fri, 6 Apr 2007 15:59:27 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Krafft",
"Gerald",
""
]
] |
0704.1828 | Dennis D. Dietrich | Dennis D. Dietrich | Gauge invariance in gravity-like descriptions of massive gauge field
theories | 11 pages | null | null | null | hep-th | null | We discuss gravity-like formulations of massive Abelian and non-Abelian gauge
field theories in four space-time dimensions with particular emphasis on the
issue of gauge invariance. Alternative descriptions in terms of antisymmetric
tensor fields and geometric variables, respectively, are analysed. In both
approaches St\"uckelberg degrees of freedom factor out. We also demonstrate, in
the Abelian case, that the massless limit for the gauge propagator, which does
not exist in the vector potential formulation, is well-defined for the
antisymmetric tensor fields.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 21:51:21 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Dietrich",
"Dennis D.",
""
]
] |
0704.1829 | Kamil Kloch | Stefan Felsner, Kamil Kloch, Grzegorz Matecki, and Piotr Micek | On-line Chain Partitions of Up-growing Semi-orders | null | null | null | null | cs.DM | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | On-line chain partition is a two-player game between Spoiler and Algorithm.
Spoiler presents a partially ordered set, point by point. Algorithm assigns
incoming points (immediately and irrevocably) to the chains which constitute a
chain partition of the order. The value of the game for orders of width $w$ is
a minimum number $\fVal(w)$ such that Algorithm has a strategy using at most
$\fVal(w)$ chains on orders of width at most $w$. We analyze the chain
partition game for up-growing semi-orders. Surprisingly, the golden ratio comes
into play and the value of the game is $\lfloor\frac{1+\sqrt{5}}{2}\; w
\rfloor$.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 22:41:21 GMT"
},
{
"version": "v2",
"created": "Thu, 20 Sep 2007 21:51:26 GMT"
},
{
"version": "v3",
"created": "Sat, 19 Feb 2011 21:18:10 GMT"
}
] | 2011-02-22T00:00:00 | [
[
"Felsner",
"Stefan",
""
],
[
"Kloch",
"Kamil",
""
],
[
"Matecki",
"Grzegorz",
""
],
[
"Micek",
"Piotr",
""
]
] |
0704.1830 | Bogdan Wojtsekhowski | D. J. Hamilton, A. Shahinyan, B. Wojtsekhowski, J. R. M. Annand, T.-H.
Chang, E. Chudakov, A. Danagoulian, P. Degtyarenko, K. Egiyan, R. Gilman, V.
Gorbenko, J. Hines, E. Hovhannisyan, C. E. Hyde-Wright, C.W. de Jager, A.
Ketikyan, V. H. Mamyan, R. Michaels, A. M. Nathan, V. Nelyubin, I. Rachek, M.
Roedelbrom, A. Petrosyan, R. Pomatsalyuk, V. Popov, J. Segal, Y. Shestakov,
J. Templon, H. Voskanyan | An Electromagnetic Calorimeter for the JLab Real Compton Scattering
Experiment | text updated according to published version | Nuclear Instruments and Methods A, Volume 643, Issue 1, 1 July
2011, Pages 17-28 | null | JLAB-PHY-07-633 | physics.ins-det nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A lead-glass hodoscope calorimeter that was constructed for use in the
Jefferson Lab Real Compton Scattering experiment is described. The detector
provides a measurement of the coordinates and the energy of scattered photons
in the GeV energy range with resolutions of 5 mm and 6%/\sqrt(E{\gamma} [GeV]).
Features of both the detector design and its performance in the high luminosity
environment during the experiment are presented.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 17:09:07 GMT"
},
{
"version": "v2",
"created": "Thu, 17 Mar 2011 15:11:26 GMT"
},
{
"version": "v3",
"created": "Fri, 25 Sep 2015 14:22:08 GMT"
}
] | 2015-09-28T00:00:00 | [
[
"Hamilton",
"D. J.",
""
],
[
"Shahinyan",
"A.",
""
],
[
"Wojtsekhowski",
"B.",
""
],
[
"Annand",
"J. R. M.",
""
],
[
"Chang",
"T. -H.",
""
],
[
"Chudakov",
"E.",
""
],
[
"Danagoulian",
"A.",
""
],
[
"Degtyarenko",
"P.",
""
],
[
"Egiyan",
"K.",
""
],
[
"Gilman",
"R.",
""
],
[
"Gorbenko",
"V.",
""
],
[
"Hines",
"J.",
""
],
[
"Hovhannisyan",
"E.",
""
],
[
"Hyde-Wright",
"C. E.",
""
],
[
"de Jager",
"C. W.",
""
],
[
"Ketikyan",
"A.",
""
],
[
"Mamyan",
"V. H.",
""
],
[
"Michaels",
"R.",
""
],
[
"Nathan",
"A. M.",
""
],
[
"Nelyubin",
"V.",
""
],
[
"Rachek",
"I.",
""
],
[
"Roedelbrom",
"M.",
""
],
[
"Petrosyan",
"A.",
""
],
[
"Pomatsalyuk",
"R.",
""
],
[
"Popov",
"V.",
""
],
[
"Segal",
"J.",
""
],
[
"Shestakov",
"Y.",
""
],
[
"Templon",
"J.",
""
],
[
"Voskanyan",
"H.",
""
]
] |
0704.1831 | Elena Bratkovskaya | V.P. Konchakovski, M.I. Gorenstein and E.L. Bratkovskaya | Multiplicity Fluctuations in Au+Au Collisions at RHIC | 7 pages, 3 figures, submitted to Phys. Rev. C (Rapid Communication) | Phys.Rev.C76:031901,2007 | 10.1103/PhysRevC.76.031901 | FIAS070413 | nucl-th | null | The preliminary data of the PHENIX collaboration for the scaled variances of
charged hadron multiplicity fluctuations in Au+Au at $\sqrt{s}=200$ GeV are
analyzed within the model of independent sources. We use the HSD transport
model to calculate the participant number fluctuations and the number of
charged hadrons per nucleon participant in different centrality bins. This
combined picture leads to a good agreement with the PHENIX data and suggests
that the measured multiplicity fluctuations result dominantly from participant
number fluctuations. The role of centrality selection and acceptance is
discussed separately.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 22:09:47 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Konchakovski",
"V. P.",
""
],
[
"Gorenstein",
"M. I.",
""
],
[
"Bratkovskaya",
"E. L.",
""
]
] |
0704.1832 | Luisa Rebull | John R. Stauffer (SSC), Lee W. Hartmann (Univ Michigan), Giovanni G.
Fazio (CfA), Lori E. Allen (CfA), Brian M. Patten (CfA), Patrick J. Lowrance
(SSC), Robert L. Hurt (SSC), Luisa M. Rebull (SSC), Roc M. Cutri (IPAC),
Solange V. Ramirez (IPAC), Erick T. Young (Univ Arizona), George H. Rieke
(Univ Arizona), Nadya I. Gorlova (Univ Arizona), James C. Muzerolle (Univ
Arizona), Cathy L. Slesnick (Caltech), Michael F. Skrutskie (Univ Virginia) | Near and Mid-IR Photometry of the Pleiades, and a New List of Substellar
Candidate Members | Accepted to ApJS; data tables and embedded-figure version available
at http://spider.ipac.caltech.edu/staff/stauffer/pleiades07/ | null | 10.1086/518961 | null | astro-ph | null | We make use of new near and mid-IR photometry of the Pleiades cluster in
order to help identify proposed cluster members. We also use the new photometry
with previously published photometry to define the single-star main sequence
locus at the age of the Pleiades in a variety of color-magnitude planes.
The new near and mid-IR photometry extend effectively two magnitudes deeper
than the 2MASS All-Sky Point Source catalog, and hence allow us to select a new
set of candidate very low mass and sub-stellar mass members of the Pleiades in
the central square degree of the cluster. We identify 42 new candidate members
fainter than Ks =14 (corresponding to 0.1 Mo). These candidate members should
eventually allow a better estimate of the cluster mass function to be made down
to of order 0.04 solar masses.
We also use new IRAC data, in particular the images obtained at 8 um, in
order to comment briefly on interstellar dust in and near the Pleiades. We
confirm, as expected, that -- with one exception -- a sample of low mass stars
recently identified as having 24 um excesses due to debris disks do not have
significant excesses at IRAC wavelengths. However, evidence is also presented
that several of the Pleiades high mass stars are found to be impacting with
local condensations of the molecular cloud that is passing through the Pleiades
at the current epoch.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 22:19:23 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Stauffer",
"John R.",
"",
"SSC"
],
[
"Hartmann",
"Lee W.",
"",
"Univ Michigan"
],
[
"Fazio",
"Giovanni G.",
"",
"CfA"
],
[
"Allen",
"Lori E.",
"",
"CfA"
],
[
"Patten",
"Brian M.",
"",
"CfA"
],
[
"Lowrance",
"Patrick J.",
"",
"SSC"
],
[
"Hurt",
"Robert L.",
"",
"SSC"
],
[
"Rebull",
"Luisa M.",
"",
"SSC"
],
[
"Cutri",
"Roc M.",
"",
"IPAC"
],
[
"Ramirez",
"Solange V.",
"",
"IPAC"
],
[
"Young",
"Erick T.",
"",
"Univ Arizona"
],
[
"Rieke",
"George H.",
"",
"Univ Arizona"
],
[
"Gorlova",
"Nadya I.",
"",
"Univ Arizona"
],
[
"Muzerolle",
"James C.",
"",
"Univ\n Arizona"
],
[
"Slesnick",
"Cathy L.",
"",
"Caltech"
],
[
"Skrutskie",
"Michael F.",
"",
"Univ Virginia"
]
] |
0704.1833 | Inanc Inan | Inanc Inan, Feyza Keceli, Ender Ayanoglu | Analysis of the 802.11e Enhanced Distributed Channel Access Function | null | null | null | null | cs.NI | null | The IEEE 802.11e standard revises the Medium Access Control (MAC) layer of
the former IEEE 802.11 standard for Quality-of-Service (QoS) provision in the
Wireless Local Area Networks (WLANs). The Enhanced Distributed Channel Access
(EDCA) function of 802.11e defines multiple Access Categories (AC) with
AC-specific Contention Window (CW) sizes, Arbitration Interframe Space (AIFS)
values, and Transmit Opportunity (TXOP) limits to support MAC-level QoS and
prioritization. We propose an analytical model for the EDCA function which
incorporates an accurate CW, AIFS, and TXOP differentiation at any traffic
load. The proposed model is also shown to capture the effect of MAC layer
buffer size on the performance. Analytical and simulation results are compared
to demonstrate the accuracy of the proposed approach for varying traffic loads,
EDCA parameters, and MAC layer buffer space.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 22:40:05 GMT"
},
{
"version": "v2",
"created": "Fri, 26 Oct 2007 05:59:08 GMT"
},
{
"version": "v3",
"created": "Fri, 28 Mar 2008 05:21:34 GMT"
}
] | 2008-03-28T00:00:00 | [
[
"Inan",
"Inanc",
""
],
[
"Keceli",
"Feyza",
""
],
[
"Ayanoglu",
"Ender",
""
]
] |
0704.1834 | Dmitri Volja | Dmitri Volja, Wei-Guo Yin and Wei Ku | Charge Ordering in Half-Doped Manganites: Weak Charge Disproportion and
Leading Mechanisms | accepted by Europhysics Letters | Europhysics Letters 89, 27008 (2010) | 10.1209/0295-5075/89/27008 | null | cond-mat.str-el | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The apparent contradiction between the recently observed weak charge
disproportion and the traditional Mn$^{3+}$/Mn$^{4+}$ picture of the
charge-orbital orders in half-doped manganites is resolved by a novel Wannier
states analysis of the LDA$+U$ electronic structure. Strong electron itinerancy
in this charge-transfer system significantly delocalizes the occupied
low-energy "Mn$^{3+}$" Wannier states such that charge leaks into the
"Mn$^{4+}$"-sites. Furthermore, the leading mechanisms of the charge order are
quantified via our first-principles derivation of the low-energy effective
Hamiltonian. The electron-electron interaction is found to play a role as
important as the electron-lattice interaction. \ignore{A general picture of
doped holes in strongly correlated charge-transfer systems is presented and
applied to the study of charge order in half-doped manganites, using a novel
Wannier states analysis of the LDA$+U$ electronic structure. While residing
primarily in the oxygen atoms, the doped holes form additional effective $e_g$
orbitals at the low-energy scale, leading to an effective Mn$^{3+}$/Mn$^{4+}$
valence picture that enables weak charge disproportion, resolving the current
serious contradictions between the recent experimental observations of charge
distribution and traditional models. Furthermore, the leading mechanisms of the
observed charge order are quantified via our first-principles derivation of the
low-energy effective Hamiltonian
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 19:10:58 GMT"
},
{
"version": "v2",
"created": "Thu, 7 Jan 2010 00:23:53 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Volja",
"Dmitri",
""
],
[
"Yin",
"Wei-Guo",
""
],
[
"Ku",
"Wei",
""
]
] |
0704.1835 | Darren Forde | Darren Forde | Direct extraction of one-loop integral coefficients | 42 pages, 7 figures | Phys.Rev.D75:125019,2007 | 10.1103/PhysRevD.75.125019 | SLAC-PUB-12455, UCLA/07/TEP/12 | hep-ph | null | We present a general procedure for obtaining the coefficients of the scalar
bubble and triangle integral functions of one-loop amplitudes. Coefficients are
extracted by considering two-particle and triple unitarity cuts of the
corresponding bubble and triangle integral functions. After choosing a specific
parameterisation of the cut loop momentum we can uniquely identify the
coefficients of the desired integral functions simply by examining the
behaviour of the cut integrand as the unconstrained parameters of the cut loop
momentum approach infinity. In this way we can produce compact forms for scalar
integral coefficients. Applications of this method are presented for both QCD
and electroweak processes, including an alternative form for the recently
computed three-mass triangle coefficient in the six-photon amplitude
$A_6(1^-,2^+,3^-,4^+,5^-,6^+)$. The direct nature of this extraction procedure
allows for a very straightforward automation of the procedure.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 01:13:11 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Forde",
"Darren",
""
]
] |
0704.1836 | Hitoshi Nishino | Hitoshi Nishino and Subhash Rajpoot | Comment on Electroweak Higgs as a Pseudo-Goldstone Boson of Broken Scale
Invariance | 2 pages, no figure | null | null | CSULB-PA-07-4 | hep-ph hep-th | null | The first model of Foot, Kobakhidze and Volkas described in their work in
arXiv:0704.1165 [hep-ph] is a tailored version of our model on broken scale
invariance in the standard model presented in hep-th/0403039.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 22:53:47 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Nishino",
"Hitoshi",
""
],
[
"Rajpoot",
"Subhash",
""
]
] |
0704.1837 | Hiroki Wadati | H. Wadati, Y. Hotta, A. Fujimori, T. Susaki, H. Y. Hwang, Y. Takata,
K. Horiba, M. Matsunami, S. Shin, M. Yabashi, K. Tamasaku, Y. Nishino, and T.
Ishikawa | Hard x-ray photoemission study of LaAlO3/LaVO3 multilayers | 5 pages, 7 figures | Phys. Rev. B 77, 045122 (2008) | 10.1103/PhysRevB.77.045122 | null | cond-mat.str-el cond-mat.mtrl-sci | null | We have studied the electronic structure of multilayers composed of a band
insulator LaAlO$_3$ (LAO) and a Mott insulator LaVO$_3$ (LVO) by means of hard
x-ray photoemission spectroscopy, which has a probing depth as large as $\sim
60 {\AA}$. The Mott-Hubbard gap of LVO remained open at the interface,
indicating that the interface is insulating unlike the LaTiO$_3$/SrTiO$_3$
multilayers. We found that the valence of V in LVO were partially converted
from V$^{3+}$ to V$^{4+}$ only at the interface on the top side of the LVO
layer and that the amount of V$^{4+}$ increased with LVO layer thickness. We
suggest that the electronic reconstruction to eliminate the polarity
catastrophe inherent in the polar heterostructure is the origin of the highly
asymmetric valence change at the LVO/LAO interfaces.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 22:54:17 GMT"
}
] | 2008-01-18T00:00:00 | [
[
"Wadati",
"H.",
""
],
[
"Hotta",
"Y.",
""
],
[
"Fujimori",
"A.",
""
],
[
"Susaki",
"T.",
""
],
[
"Hwang",
"H. Y.",
""
],
[
"Takata",
"Y.",
""
],
[
"Horiba",
"K.",
""
],
[
"Matsunami",
"M.",
""
],
[
"Shin",
"S.",
""
],
[
"Yabashi",
"M.",
""
],
[
"Tamasaku",
"K.",
""
],
[
"Nishino",
"Y.",
""
],
[
"Ishikawa",
"T.",
""
]
] |
0704.1838 | Inanc Inan | Inanc Inan, Feyza Keceli, Ender Ayanoglu | Performance Analysis of the IEEE 802.11e Enhanced Distributed
Coordination Function using Cycle Time Approach | null | null | null | null | cs.OH | null | The recently ratified IEEE 802.11e standard defines the Enhanced Distributed
Channel Access (EDCA) function for Quality-of-Service (QoS) provisioning in the
Wireless Local Area Networks (WLANs). The EDCA uses Carrier Sense Multiple
Access with Collision Avoidance (CSMA/CA) and slotted Binary Exponential
Backoff (BEB) mechanism. We present a simple mathematical analysis framework
for the EDCA function. Our analysis considers the fact that the distributed
random access systems exhibit cyclic behavior where each station successfully
transmits a packet in a cycle. Our analysis shows that an AC-specific cycle
time exists for the EDCA function. Validating the theoretical results via
simulations, we show that the proposed analysis accurately captures EDCA
saturation performance in terms of average throughput, medium access delay, and
packet loss ratio. The cycle time analysis is a simple and insightful
substitute for previously proposed more complex EDCA models.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 23:01:40 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Inan",
"Inanc",
""
],
[
"Keceli",
"Feyza",
""
],
[
"Ayanoglu",
"Ender",
""
]
] |
0704.1839 | Vladimir Makarenko | V. Makarenko | ALHEP symbolic algebra program for high-energy physics | 33 pages, 4 figures | null | null | null | hep-ph | null | ALHEP is the symbolic algebra program for high-energy physics. It deals with
amplitudes calculation, matrix element squaring, Wick theorem, dimensional
regularization, tensor reduction of loop integrals and simplification of final
expressions. The program output includes: Fortran code for differential cross
section, Mathematica files to view results and intermediate steps and TeX
source for Feynman diagrams. The PYTHIA interface is available. The project
website http://www.hep.by/alhep contains up-to-date executables, manual and
script examples.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 23:02:17 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Makarenko",
"V.",
""
]
] |
0704.1840 | Mya Warren | Mya Warren and Joerg Rottler | Simulations of aging and plastic deformation in polymer glasses | 9 pages, 12 figures | null | 10.1103/PhysRevE.76.031802 | null | cond-mat.soft cond-mat.mtrl-sci | null | We study the effect of physical aging on the mechanical properties of a model
polymer glass using molecular dynamics simulations. The creep compliance is
determined simultaneously with the structural relaxation under a constant
uniaxial load below yield at constant temperature. The model successfully
captures universal features found experimentally in polymer glasses, including
signatures of mechanical rejuvenation. We analyze microscopic relaxation
timescales and show that they exhibit the same aging characteristics as the
macroscopic creep compliance. In addition, our model indicates that the entire
distribution of relaxation times scales identically with age. Despite large
changes in mobility, we observe comparatively little structural change except
for a weak logarithmic increase in the degree of short-range order that may be
correlated to an observed decrease in aging with increasing load.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 23:05:22 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Warren",
"Mya",
""
],
[
"Rottler",
"Joerg",
""
]
] |
0704.1841 | Joan Najita | Joan R. Najita, John S. Carr, Alfred E. Glassgold, and Jeff Valenti | Gaseous Inner Disks | 16 pages, 6 figures, a chapter in "Protostars and Planets V" | null | null | null | astro-ph | null | As the likely birthplaces of planets and an essential conduit for the buildup
of stellar masses, inner disks are of fundamental interest in star and planet
formation. Studies of the gaseous component of inner disks are of interest
because of their ability to probe the dynamics, physical and chemical
structure, and gas content of this region. We review the observational and
theoretical developments in this field, highlighting the potential of such
studies to, e.g., measure inner disk truncation radii, probe the nature of the
disk accretion process, and chart the evolution in the gas content of disks.
Measurements of this kind have the potential to provide unique insights on the
physical processes governing star and planet formation.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 23:07:56 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Najita",
"Joan R.",
""
],
[
"Carr",
"John S.",
""
],
[
"Glassgold",
"Alfred E.",
""
],
[
"Valenti",
"Jeff",
""
]
] |
0704.1842 | Inanc Inan | Feyza Keceli, Inanc Inan, Ender Ayanoglu | Fairness Provision in the IEEE 802.11e Infrastructure Basic Service Set | null | null | null | null | cs.OH | null | Most of the deployed IEEE 802.11e Wireless Local Area Networks (WLANs) use
infrastructure Basic Service Set (BSS) in which an Access Point (AP) serves as
a gateway between wired and wireless domains. We present the unfairness problem
between the uplink and the downlink flows of any Access Category (AC) in the
802.11e Enhanced Distributed Channel Access (EDCA) when the default settings of
the EDCA parameters are used. We propose a simple analytical model to calculate
the EDCA parameter settings that achieve weighted fair resource allocation for
all uplink and downlink flows. We also propose a simple model-assisted
measurement-based dynamic EDCA parameter adaptation algorithm. Moreover, our
dynamic solution addresses the differences in the transport layer and the
Medium Access Control (MAC) layer interactions of User Datagram Protocol (UDP)
and Transmission Control Protocol (TCP). We show that proposed Contention
Window (CW) and Transmit Opportunity (TXOP) limit adaptation at the AP provides
fair UDP and TCP access between uplink and downlink flows of the same AC while
preserving prioritization among ACs.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 23:11:27 GMT"
},
{
"version": "v2",
"created": "Thu, 13 Sep 2007 15:08:17 GMT"
}
] | 2007-09-13T00:00:00 | [
[
"Keceli",
"Feyza",
""
],
[
"Inan",
"Inanc",
""
],
[
"Ayanoglu",
"Ender",
""
]
] |
0704.1843 | Edison Liang | Edison Liang and Koichi Noguchi | Radiation from Kinetic Poynting Flux Acceleration | 25 pages, 11 figures, revised paper resubmitted to Astrophysical
Journal | null | null | null | astro-ph | null | We derive analytic formulas for the power output and critical frequency of
radiation by electrons accelerated by relativistic kinetic Poynting flux, and
validate these results with Particle-In-Cell plasma simulations. We find that
the in-situ radiation power output and critical frequency are much below those
predicted by the classical synchrotron formulae. We discuss potential
astrophysical applications of these results.
| [
{
"version": "v1",
"created": "Fri, 13 Apr 2007 23:20:54 GMT"
},
{
"version": "v2",
"created": "Sun, 18 Nov 2007 20:23:37 GMT"
}
] | 2007-11-18T00:00:00 | [
[
"Liang",
"Edison",
""
],
[
"Noguchi",
"Koichi",
""
]
] |
0704.1844 | Kazuyuki Fujii | Kazuyuki Fujii (Yokohama City University) | A New Algebraic Structure of Finite Quantum Systems and the Modified
Bessel Functions | Latex ; 14 pages ; no figure ; minor changes. To appear in
International Journal of Geometric Methods in Modern Physics, (Vo.4, No.7),
2007 | Int.G.Geom.Meth.Mod.Phys. 4(2007) 1205-1215 | 10.1142/S021988780700251X | null | quant-ph math-ph math.MP | null | In this paper we present a new algebraic structure (a super hyperbolic system
in our terminology) for finite quantum systems, which is a generalization of
the usual one in the two-level system.
It fits into the so-called generalized Pauli matrices, so they play an
important role in the theory. Some deep relation to the modified Bessel
functions of integer order is pointed out.
By taking a skillful limit finite quantum systems become quantum mechanics on
the circle developed by Ohnuki and Kitakado.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 00:20:40 GMT"
},
{
"version": "v2",
"created": "Tue, 17 Jul 2007 00:08:48 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Fujii",
"Kazuyuki",
"",
"Yokohama City University"
]
] |
0704.1845 | Donal O'Connell | Benjamin Grinstein, Donal O'Connell and Mark B. Wise | The Lee-Wick Standard Model | 20 pages, 4 figures. Improved discussion and reference added. Contour
prescription clarified | Phys.Rev.D77:025012,2008 | 10.1103/PhysRevD.77.025012 | CALT 68-2643, UCSD/PTH 07-04 | hep-ph hep-th | null | We construct a modification of the standard model which stabilizes the Higgs
mass against quadratically divergent radiative corrections, using ideas
originally discussed by Lee and Wick in the context of a finite theory of
quantum electrodynamics. The Lagrangian includes new higher derivative
operators. We show that the higher derivative terms can be eliminated by
introducing a set of auxiliary fields; this allows for convenient computation
and makes the physical interpretation more transparent. Although the theory is
unitary, it does not satisfy the usual analyticity conditions.
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 01:25:57 GMT"
},
{
"version": "v2",
"created": "Tue, 1 May 2007 08:32:51 GMT"
},
{
"version": "v3",
"created": "Tue, 24 Jul 2007 13:15:12 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Grinstein",
"Benjamin",
""
],
[
"O'Connell",
"Donal",
""
],
[
"Wise",
"Mark B.",
""
]
] |
0704.1846 | Meinolf Geck | Meinolf Geck, Lacrimioara Iancu and Christos Pallikaros | Specht modules and Kazhdan--Lusztig cells in type $B_n$ | the revised version corrects some minor errors | null | null | null | math.RT | null | Dipper, James and Murphy generalized the classical Specht module theory to
Hecke algebras of type $B_n$. On the other hand, for any choice of a monomial
order on the parameters in type $B_n$, we obtain corresponding Kazhdan--Lusztig
cell modules. In this paper, we show that the Specht modules are naturally
equivalent to the Kazhdan--Lusztig cell modules {\em if} we choose the
dominance order on the parameters, as in the ``asymptotic case'' studied by
Bonnaf\'e and the second named author. We also give examples which show that
such an equivalence does not hold for other choices of monomial orders.
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 19:52:02 GMT"
},
{
"version": "v2",
"created": "Wed, 13 Jun 2007 12:36:43 GMT"
}
] | 2007-06-13T00:00:00 | [
[
"Geck",
"Meinolf",
""
],
[
"Iancu",
"Lacrimioara",
""
],
[
"Pallikaros",
"Christos",
""
]
] |
0704.1847 | Daniel Fraiman | Daniel Fraiman | Growing Networks: Limit in-degree distribution for arbitrary out-degree
one | 12 pages, 6 figures, v2 adds a section on descriptive statistics, an
analisis on www network, typos added | The European Physical Journal B 61 3 (2008) 377-388 | 10.1140/epjb/e2008-00075-3 | null | physics.soc-ph physics.data-an | null | We compute the stationary in-degree probability, $P_{in}(k)$, for a growing
network model with directed edges and arbitrary out-degree probability. In
particular, under preferential linking, we find that if the nodes have a light
tail (finite variance) out-degree distribution, then the corresponding
in-degree one behaves as $k^{-3}$. Moreover, for an out-degree distribution
with a scale invariant tail, $P_{out}(k)\sim k^{-\alpha}$, the corresponding
in-degree distribution has exactly the same asymptotic behavior only if
$2<\alpha<3$ (infinite variance). Similar results are obtained when
attractiveness is included. We also present some results on descriptive
statistics measures %descriptive statistics such as the correlation between the
number of in-going links, $D_{in}$, and outgoing links, $D_{out}$, and the
conditional expectation of $D_{in}$ given $D_{out}$, and we calculate these
measures for the WWW network. Finally, we present an application to the
scientific publications network. The results presented here can explain the
tail behavior of in/out-degree distribution observed in many real networks.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 01:29:04 GMT"
},
{
"version": "v2",
"created": "Fri, 12 Oct 2007 12:23:26 GMT"
}
] | 2008-10-21T00:00:00 | [
[
"Fraiman",
"Daniel",
""
]
] |
0704.1848 | Shinji Tsujikawa | Maxim Libanov, Eleftherios Papantonopoulos, Valery Rubakov, M. Sami,
Shinji Tsujikawa | UV stable, Lorentz-violating dark energy with transient phantom era | 22 pages, 7 figures; Presentation modified substantially, results and
conclusions unchanged. Journal version | JCAP0708:010,2007 | 10.1088/1475-7516/2007/08/010 | null | hep-th astro-ph gr-qc hep-ph | null | Phantom fields with negative kinetic energy are often plagued by the vacuum
quantum instability in the ultraviolet region. We present a Lorentz-violating
dark energy model free from this problem and show that the crossing of the
cosmological constant boundary w=-1 to the phantom equation of state is
realized before reaching a de Sitter attractor. Another interesting feature is
a peculiar time-dependence of the effective Newton's constant; the magnitude of
this effect is naturally small but may be close to experimental limits. We also
derive momentum scales of instabilities at which tachyons or ghosts appear in
the infrared region around the present Hubble scale and clarify the conditions
under which tachyonic instabilities do not spoil homogeneity of the
present/future Universe.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 02:58:52 GMT"
},
{
"version": "v2",
"created": "Thu, 19 Jul 2007 00:46:31 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Libanov",
"Maxim",
""
],
[
"Papantonopoulos",
"Eleftherios",
""
],
[
"Rubakov",
"Valery",
""
],
[
"Sami",
"M.",
""
],
[
"Tsujikawa",
"Shinji",
""
]
] |
0704.1849 | Sheng-Jun Wang | Sheng-Jun Wang, An-Cai Wu, Zhi-Xi Wu, Xin-Jian Xu, Ying-Hai Wang | Response of degree-correlated scale-free networks to stimuli | 5 pages, 5 figures | Physical Review E 75, 046113 (2007) | 10.1103/PhysRevE.75.046113 | null | cond-mat.dis-nn | null | The response of degree-correlated scale-free attractor networks to stimuli is
studied. We show that degree-correlated scale-free networks are robust to
random stimuli as well as the uncorrelated scale-free networks, while
assortative (disassortative) scale-free networks are more (less) sensitive to
directed stimuli than uncorrelated networks. We find that the
degree-correlation of scale-free networks makes the dynamics of attractor
systems different from uncorrelated ones. The dynamics of correlated scale-free
attractor networks result in the effects of degree correlation on the response
to stimuli.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 03:19:46 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Wang",
"Sheng-Jun",
""
],
[
"Wu",
"An-Cai",
""
],
[
"Wu",
"Zhi-Xi",
""
],
[
"Xu",
"Xin-Jian",
""
],
[
"Wang",
"Ying-Hai",
""
]
] |
0704.1850 | Damian Swift | Damian C. Swift, Achim Seifter, David B. Holtkamp, David A. Clark | Shock and Release Temperatures in Molybdenum | null | Physical Review B, vol 76, 054122 (2007) | 10.1103/PhysRevB.76.054122 | LA-UR-07-1660 | cond-mat.mtrl-sci | null | Shock and release temperatures in Mo were calculated, taking account of
heating from plastic flow predicted using the Steinberg-Guinan model. Plastic
flow was calculated self-consistently with the shock jump conditions: this is
necessary for a rigorous estimate of the locus of shock states accessible. The
temperatures obtained were significantly higher than predicted assuming ideal
hydrodynamic loading. The temperatures were compared with surface emission
spectrometry measurements for Mo shocked to around 60GPa and then released into
vacuum or into a LiF window. Shock loading was induced by the impact of a
planar projectile, accelerated by high explosive or in a gas gun. Surface
velocimetry showed an elastic wave at the start of release from the shocked
state; the amplitude of the elastic wave matched the prediction to around 10%,
indicating that the predicted flow stress in the shocked state was reasonable.
The measured temperatures were consistent with the simulations, indicating that
the fraction of plastic work converted to heat was in the range 70-100% for
these loading conditions.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 03:28:22 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Swift",
"Damian C.",
""
],
[
"Seifter",
"Achim",
""
],
[
"Holtkamp",
"David B.",
""
],
[
"Clark",
"David A.",
""
]
] |
0704.1851 | Shengli Kong | Shengli Kong, Peter Li and Detang Zhou | Spectrum of the Laplacian on Quaternionic Kahler Manifolds | 46 pages | J. Differential Geom. 78 (2008), 295-332 | null | null | math.DG | null | Let $M^{4n}$ be a complete quaternionic K\"ahler manifold with scalar
curvature bounded below by $-16n(n+2)$. We get a sharp estimate for the first
eigenvalue $\lambda_1(M)$ of the Laplacian which is $\lambda_1(M)\le (2n+1)^2$.
If the equality holds, then either $M$ has only one end, or $M$ is
diffeomorphic to $\mathbb{R}\times N$ with N given by a compact manifold.
Moreover, if $M$ is of bounded curvature, $M$ is covered by the quaterionic
hyperbolic space $\mathbb{QH}^n$ and $N$ is a compact quotient of the
generalized Heisenberg group. When $\lambda_1(M)\ge \frac{8(n+2)}3$, we also
prove that $M$ must have only one end with infinite volume.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 03:40:22 GMT"
}
] | 2011-03-14T00:00:00 | [
[
"Kong",
"Shengli",
""
],
[
"Li",
"Peter",
""
],
[
"Zhou",
"Detang",
""
]
] |
0704.1852 | Ellen Williams | O. Bondarchuk, W.G. Cullen, M. Degawa and Ellen D. Williams | Biased Structural Fluctuations due to Electron Wind Force | 15 pages | null | null | null | cond-mat.mtrl-sci cond-mat.stat-mech | null | Direct correlation between temporal structural fluctuations and electron wind
force is demonstrated, for the first time, by STM imaging and analysis of
atomically-resolved motion on a thin film surface under large applied current
(10e5 Amp/sqare cm). The magnitude of the momentum transfer between current
carriers and atoms in the fluctuating structure is at least five to fifteen
times (plus or minus one sigma range) larger than for freely diffusing adatoms.
The corresponding changes in surface resistivity will contribute significant
fluctuation signature to nanoscale electronic properties.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 04:08:56 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bondarchuk",
"O.",
""
],
[
"Cullen",
"W. G.",
""
],
[
"Degawa",
"M.",
""
],
[
"Williams",
"Ellen D.",
""
]
] |
0704.1853 | Hajime Susa | Hideki Maki and Hajime Susa | Dissipation of Magnetic Flux in Primordial Star Formation: From Run-away
Phase to Mass Accretion Phase | 12 pages, 7 figures, PASJ accepted | null | 10.1093/pasj/59.4.787 | null | astro-ph | null | We investigate the dissipation of magnetic flux in primordial star-forming
clouds throughout their collapse including the run-away collapse phase as well
as the accretion phase. We solve the energy equation and the non-equilibrium
chemical reactions in the collapsing gas, in order to obtain the radial
distribution of the ionized fraction during the collapse. As a result, we find
the ionized fraction is high enough for the magnetic field to couple with the
gas throughout the evolution of the cloud. This result suggests that the jet
formation from protostars as well as the activation of magneto-rotational
instability in the accretion disk are enabled in the presence of the
cosmological seed magnetic flux proposed by Langer et al.(2003).
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 04:37:57 GMT"
}
] | 2019-08-19T00:00:00 | [
[
"Maki",
"Hideki",
""
],
[
"Susa",
"Hajime",
""
]
] |
0704.1854 | Sanjoy Mahajan | Sanjoy Mahajan | Teaching for transfer | 3 pages, 3 figures, ConTeXt, GPL free-software license; from a
workshop on curriculum integration at MIT (2006-09-25) | null | null | null | physics.ed-ph | null | Students, after they leave our care, are called to solve the diverse problems
of the world, so we should teach to increase transfer: the ability to apply
fundamental principles to new problems and contexts. This ability is rare. The
following pages are from a workshop for faculty on designing courses that
promote transfer. I discuss two design principles: to name the transferable
ideas and to illustrate them with examples from diverse subjects. The
discussion uses dimensional reasoning as the example of a valuable transferable
idea, illustrating it with three diverse examples.
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 05:15:31 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Mahajan",
"Sanjoy",
""
]
] |
0704.1855 | Tianjun Li | Ching-Ming Chen, Tianjun Li, V. E. Mayes, Dimitri V. Nanopoulos | Variations of the Hidden Sector in a Realistic Intersecting Brane Model | RevTex4, 15 pages, 10 tables | J.Phys.G35:095008,2008 | 10.1088/0954-3899/35/9/095008 | ACT-02-07, MIFP-07-11 | hep-th | null | Recently, we discussed the first example of a phenomenologically realistic
intersecting D6-brane model. In this model, the gauge symmetry in the hidden
sector is USp(2)_1 x USp(2)_2 x USp(2)_3 x USp(2)_4. However, we find that the
USp(2)_1 x USp(2)_2 gauge symmetry can be replaced by an U(2)_{12} gauge
symmetry, and/or the USp(2)_3 x USp(2)_4 gauge symmetry can be replaced by an
U(2)_{34} gauge symmetry since the USp(2)^2 stacks of D6-branes contribute to
the same Ramond-Ramond tadpoles as those of the U(2) stacks. Thus, there are
three non-equivalent variations of the hidden sector, and the corresponding
gauge symmetries are U(2)_{12} x USp(2)_3 x USp(2)_4, U(2)_{34} x USp(2)_1 x
USp(2)_2, and U(2)_{12} x U(2)_{34}, respectively. Moreover, we study the
hidden sector gauge symmetry breaking, discuss how to decouple the additional
exotic particles, and briefly comment on the phenomenological consequences.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 00:17:36 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Chen",
"Ching-Ming",
""
],
[
"Li",
"Tianjun",
""
],
[
"Mayes",
"V. E.",
""
],
[
"Nanopoulos",
"Dimitri V.",
""
]
] |
0704.1856 | Yoshiko Kanada-En'yo | Yoshiko Kanada-En'yo, Osamu Morimatsu and Tetsuo Nishikawa | Axial Vector Tetraquark with Two s-quarks | prepared for Yukawa International Seminars "New Frontiers in QCD"
(YKIS2006), Nov. 20-Dec. 8, 2006, Kyoto, Japan, to appear in Prog. Theor.
Phys. Suppl | Prog.Theor.Phys.Suppl.168:194-197,2007 | 10.1143/PTPS.168.194 | null | nucl-th | null | Possibility of an axial vector isoscalar tetraquark $ud\bar{s}\bar{s}$ is
discussed. If a $f_1$ meson in the mass region $1.4-1.5$ GeV consists of four
quarks $ns\bar{n}\bar{s}$, the mass of the isoscalar
$ud\bar{s}\bar{s}$($\vartheta^+$-meson) state with $J^P=1^+$ is expected to be
lower than that of the $f_1$ meson. Within a flux-tube quark model, a possible
resonant state of $ud\bar{s}\bar{s}(J^{P}=1^{+})$ is suggested to appear at
$\sim$ 1.4 GeV with the width ${\cal{O}}(20\sim 50)$ MeV. We propose that the
$\vartheta^+$-meson is the good candidate for the tetraquark search, which
would be observed in the $K^+K^+\pi^-$ decay channel.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 08:31:30 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kanada-En'yo",
"Yoshiko",
""
],
[
"Morimatsu",
"Osamu",
""
],
[
"Nishikawa",
"Tetsuo",
""
]
] |
0704.1857 | Hsiao-Ping Hsu | Hsiao-Ping Hsu, Kurt Binder, Leonid I. Klushin, and Alexander M.
Skvortsov | What is the order of 2D polymer escape transition? | 16 pages, 21 figures, and 4 tables. Edited for typos | Phys. Rev. E 76, 021108 (2007) | 10.1103/PhysRevE.76.021108 | null | cond-mat.stat-mech cond-mat.soft | null | An end-grafted flexible polymer chain in 3d space between two pistons
undergoes an abrupt transition from a confined coil to a flower-like
conformation when the number of monomers in the chain, N, reaches a critical
value. In 2d geometry, excluded volume interactions between monomers of a chain
confined inside a strip of finite length 2L transform the coil conformation
into a linear string of blobs. However, the blob picture raises questions on
the nature of this escape transition. To check the theoretical predictions
based on the blob picture we study 2d single polymer chains with excluded
volume interactions and with one end grafted in the middle of a strip of length
2L and width H by simulating self-avoiding walks on a square lattice with the
pruned-enriched-Rosenbluth method (PERM). We estimate the free energy, the
end-to-end distance, the number of imprisoned monomers, the order parameter,
and its distribution. It is shown that in the thermodynamic limit of large N
and L but finite L/N, there is a small but finite jump in several average
characteristics, including the order parameter. We also present a theoretical
description based on the Landau free energy approach, which is in good
agreement with the simulation results. Both simulation results and the
analytical theory indicate that the 2d escape transition is a weak first-order
phase transition.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 09:45:33 GMT"
},
{
"version": "v2",
"created": "Mon, 10 Sep 2007 12:00:16 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Hsu",
"Hsiao-Ping",
""
],
[
"Binder",
"Kurt",
""
],
[
"Klushin",
"Leonid I.",
""
],
[
"Skvortsov",
"Alexander M.",
""
]
] |
0704.1858 | Fabian Walter | Fabian Walter and Chris Carilli | Detecting the Most Distant (z>7) Objects with ALMA | to appear in Astrophysics and Space Science, "Science with ALMA: a
new era for Astrophysics", ed. R. Bachiller | Astrophys.Space Sci.313:313-316,2008 | 10.1007/s10509-007-9634-1 | null | astro-ph | null | Detecting and studying objects at the highest redshifts, out to the end of
Cosmic Reionization at z>7, is clearly a key science goal of ALMA. ALMA will in
principle be able to detect objects in this redshift range both from high-J
(J>7) CO transitions and emission from ionized carbon, [CII], which is one of
the main cooling lines of the ISM. ALMA will even be able to resolve this
emission for individual targets, which will be one of the few ways to determine
dynamical masses for systems in the Epoch of Reionization. We discuss some of
the current problems regarding the detection and characterization of objects at
high redshifts and how ALMA will eliminate most (but not all) of them.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 10:00:18 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Walter",
"Fabian",
""
],
[
"Carilli",
"Chris",
""
]
] |
0704.1859 | Ryszard Szwarc | T. Pytlik, R. Szwarc | Weak type radial convolution operators on free group | null | null | null | null | math.FA | null | Radial convolution operators on free groups with nonnegative kernel of weak
type $(2,2)$ and of restricted weak type $(2,2)$ are characterized. Estimates
of weak type $(p,p)$ are obtained as well for $1<p<2.$
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 10:53:15 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Pytlik",
"T.",
""
],
[
"Szwarc",
"R.",
""
]
] |
0704.1860 | Chien Peng | Chien Y. Peng (STScI) | How Mergers May Affect The Mass Scaling Relations Between Black Holes,
Galaxies, and Other Gravitationally Bound Systems | 10 pages, 8 figures, ApJ in press, includes ApJ corrections | null | 10.1086/522774 | null | astro-ph | null | Supermassive black hole (BH) masses (MBH) are strongly correlated with galaxy
stellar bulge masses (Mbulge) and there are several ideas to explain the origin
of this relationship. This study isolates the role of galaxy mergers from
considerations of other detailed physics to more clearly show how a linear
BH-galaxy mass relation (MBH-Mgal) can naturally emerge regardless of how
primordial BHs were seeded inside galaxies, if the galaxy mass function
declines with increasing mass. Under this circumstance, the MBH-Mgal relation
is a passive attractor that eventually converges to a tight linear relation
because of two basic statistical effects: a central limit-like tendency for
galaxy mergers which is much stronger for major mergers than minor mergers, and
a convergence toward a linear relation that is due mainly to minor mergers. A
curious consequence of this thought experiment is that, if galaxy bulges are
formed by major mergers, then merging statistics naturally show that MBH would
correlate more strongly with bulge dominated galaxies, because of stronger
central-seeking tendencies, than with disk dominated galaxies. Even if some
other physics is ultimately responsible for causing a linear MBH-Mbulge
relationship, this thought experiment shows that, counter to intuition, random
merging of galaxies that harbor random BH masses tends to strengthen rather
than weaken a pre-existing, linear, correlation. This idea may be generalized
to other gravitationally bound systems (dark matter halo, compact nuclear
objects) that retain their physical identities after experiencing mergers.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 18:56:32 GMT"
},
{
"version": "v2",
"created": "Fri, 20 Apr 2007 17:37:32 GMT"
},
{
"version": "v3",
"created": "Sat, 21 Apr 2007 16:51:01 GMT"
},
{
"version": "v4",
"created": "Fri, 10 Aug 2007 18:20:45 GMT"
},
{
"version": "v5",
"created": "Wed, 24 Oct 2007 04:48:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Peng",
"Chien Y.",
"",
"STScI"
]
] |
0704.1861 | Mauricio Sepulveda | Mauricio Sepulveda (GI2MA), Octavio Vera | Analycity and smoothing effect for the coupled system of equations of
Korteweg - de Vries type with a single point singularity | null | Acta Applicandae Mathematicae. vol 113, 1 (2011) | 10.1007/s10440-010-9586-2 | null | math.AP | null | We study that a solution of the initial value problem associated for the
coupled system of equations of Korteweg - de Vries type which appears as a
model to describe the strong interaction of weakly nonlinear long waves, has
analyticity in time and smoothing effect up to real analyticity if the initial
data only has a single point singularity at $x=0.$
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 11:13:42 GMT"
}
] | 2013-10-30T00:00:00 | [
[
"Sepulveda",
"Mauricio",
"",
"GI2MA"
],
[
"Vera",
"Octavio",
""
]
] |
0704.1862 | Mauricio Sepulveda | Mauricio Sepulveda (GI2MA), Octavio Vera | Smoothing properties for the higher order nonlinear Schr\"{o}dinger
equation with constant coefficients | null | Nonlinear Analysis, TMA, Vol 71 (2009) 948-966 | 10.1016/j.na.2008.11.010 | null | math.AP | null | We study local and global existence and smoothing properties for the initial
value problem associated to a higher order nonlinear Schr\"odinger equation
with constant coefficients which appears as a model for propagation of pulse in
optical fiber.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 11:15:03 GMT"
}
] | 2013-10-30T00:00:00 | [
[
"Sepulveda",
"Mauricio",
"",
"GI2MA"
],
[
"Vera",
"Octavio",
""
]
] |
0704.1863 | Gerhard Mallot | COMPASS Collaboration, M. Alekseev, et al | Double spin asymmetry in exclusive rho^0 muoproduction at COMPASS | 6 Figures, 15 pages, version 2 with updated author list, technical
latex problem fixed | Eur.Phys.J.C52:255-265,2007 | 10.1140/epjc/s10052-007-0376-6 | CERN-PH-EP_2007-009 | hep-ex | null | The longitudinal double spin asymmetry A_1^rho for exclusive leptoproduction
of rho^0 mesons, mu + N -> mu + N + rho, is studied using the COMPASS 2002 and
2003 data. The measured reaction is incoherent exclusive rho^0 production on
polarised deuterons. The Q^2 and x dependence of A_1^rho is presented in a wide
kinematical range: 3x10^-3 < Q^2 < 7 (GeV/c)^2 and 5x10^-5 < x < 0.05. The
presented results are the first measurements of A_1^rho at small Q2 (Q2 < 0.1
(GeV/c)^2) and small x (x < 3x10^-3). The asymmetry is in general compatible
with zero in the whole kinematical range.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 12:25:50 GMT"
},
{
"version": "v2",
"created": "Tue, 10 Jul 2007 15:36:37 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"COMPASS Collaboration",
"",
""
],
[
"Alekseev",
"M.",
""
]
] |
0704.1864 | Jonas Schou Neergaard-Nielsen | J. S. Neergaard-Nielsen, B. Melholt Nielsen, H. Takahashi, A. I.
Vistnes, and E. S. Polzik | High purity bright single photon source | 9 pages, 4 figures; minor changes, added reference | Opt. Express 15, 7940-7949 (2007) | 10.1364/OE.15.007940 | null | quant-ph | null | Using cavity-enhanced non-degenerate parametric downconversion, we have built
a frequency tunable source of heralded single photons with a narrow bandwidth
of 8 MHz, making it compatible with atomic quantum memories. The photon state
is 70% pure single photon as characterized by a tomographic measurement and
reconstruction of the quantum state, revealing a clearly negative Wigner
function. Furthermore, it has a spectral brightness of ~1,500 photons/s per MHz
bandwidth, making it one of the brightest single photon sources available. We
also investigate the correlation function of the down-converted fields using a
combination of two very distinct detection methods; photon counting and
homodyne measurement.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 12:18:28 GMT"
},
{
"version": "v2",
"created": "Tue, 5 Jun 2007 06:30:10 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Neergaard-Nielsen",
"J. S.",
""
],
[
"Nielsen",
"B. Melholt",
""
],
[
"Takahashi",
"H.",
""
],
[
"Vistnes",
"A. I.",
""
],
[
"Polzik",
"E. S.",
""
]
] |
0704.1865 | SongPing Zhou | Dan Sheng Yu, Ping Zhou and Song Ping Zhou | On $L^{1}$-Convergence of Fourier Series Under $MVBV$ Condition | 13 Pages, Accepted by Canad. Math. Bull | null | null | null | math.CA | null | Let $f\in L_{2\pi}$ be a real-valued even function with its Fourier series $
\frac{a_{0}}{2}+\sum_{n=1}^{\infty}a_{n}\cos nx,$ and let $S_{n}(f,x), n\geq
1,$ be the $n$-th partial sum of the Fourier series. It is well-known that if
the nonnegative sequence $\{a_{n}\}$ is decreasing and $\lim\limits_{n\to
\infty}a_{n}=0$, then $$ \lim\limits_{n\to \infty}\Vert f-S_{n}(f)\Vert_{L}=0
{if and only if} \lim\limits_{n\to \infty}a_{n}\log n=0. $$ We weaken the
monotone condition in this classical result to the so-called mean value bounded
variation ($MVBV$) condition. The generalization of the above classical result
in real-valued function space is presented as a special case of the main result
in this paper which gives the $L^{1}$% -convergence of a function $f\in
L_{2\pi}$ in complex space. We also give results on $L^{1}$-approximation of a
function $f\in L_{2\pi}$ under the $% MVBV$ condition.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 12:50:22 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Yu",
"Dan Sheng",
""
],
[
"Zhou",
"Ping",
""
],
[
"Zhou",
"Song Ping",
""
]
] |
0704.1866 | Changxing Miao | Changxing Miao, Junyong Zhang | On global solution to the Klein-Gordon-Hartree equation below energy
space | 31 pages | J. Differential Equations, 250 (2011) 3418-3447 | 10.1016/j.jde.2010.12.010 | null | math.AP math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we consider the Cauchy problem for Klein-Gordon equation with
a cubic convolution nonlinearity in $\R^3$. By making use of Bourgain's method
in conjunction with a precise Strichartz estimate of S.Klainerman and D.Tataru,
we establish the $H^s (s<1)$ global well-posedness of the Cauchy problem for
the cubic convolution defocusing Klein-Gordon-Hartree equation. Before arriving
at the previously discussed conclusion, we obtain global solution for this
non-scaling equation with small initial data in $H^{s_0}\times H^{s_0-1}$ where
$s_0=\frac\gamma 6$ but not $\frac\gamma2-1$, for this equation that we
consider is a subconformal equation in some sense. In doing so a number of
nonlinear prior estimates are already established by using Bony's
decomposition, flexibility of Klein-Gordon admissible pairs which are slightly
different from that of wave equation and a commutator estimate. We establish
this commutator estimate by exploiting cancellation property and utilizing
Coifman and Meyer multilinear multiplier theorem. As far as we know, it seems
that this is the first result on low regularity for this Klein-Gordon-Hartree
equation.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 13:16:38 GMT"
},
{
"version": "v2",
"created": "Sat, 5 May 2007 13:41:41 GMT"
},
{
"version": "v3",
"created": "Mon, 28 May 2007 01:43:08 GMT"
},
{
"version": "v4",
"created": "Sat, 6 Jun 2009 01:33:30 GMT"
}
] | 2011-02-22T00:00:00 | [
[
"Miao",
"Changxing",
""
],
[
"Zhang",
"Junyong",
""
]
] |
0704.1867 | Heiko Bauke | Heiko Bauke | Parameter estimation for power-law distributions by maximum likelihood
methods | Supplementary software:
http://www.physics.ox.ac.uk/users/bauke/Publications/index.html#powerlaws | The European Physical Journal B, vol. 58, no. 2, pp. 167-173
(2007) | 10.1140/epjb/e2007-00219-y | null | cond-mat.other physics.data-an | null | Distributions following a power-law are an ubiquitous phenomenon. Methods for
determining the exponent of a power-law tail by graphical means are often used
in practice but are intrinsically unreliable. Maximum likelihood estimators for
the exponent are a mathematically sound alternative to graphical methods.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 14:29:00 GMT"
},
{
"version": "v2",
"created": "Sat, 11 Aug 2007 11:36:30 GMT"
}
] | 2007-08-11T00:00:00 | [
[
"Bauke",
"Heiko",
""
]
] |
0704.1868 | Jan H. Bruinier | Jan H. Bruinier and Oliver Stein | The Weil representation and Hecke operators for vector valued modular
forms | 23 pages | null | null | null | math.NT | null | We define Hecke operators on vector valued modular forms transforming with
the Weil representation associated to a discriminant form. We describe the
properties of the corresponding algebra of Hecke operators and study the action
on modular forms.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 13:46:52 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bruinier",
"Jan H.",
""
],
[
"Stein",
"Oliver",
""
]
] |
0704.1869 | Nagalakshmi Rao A | Nagalakshmi A Rao and B. A. Kagali | On the energy spectrum of the one-dimensional Klein-Gordon Oscillator | Latex, 9 Pages, 1 Table, Added Reference | Physica Scripta Phys.Scr 77(2008) 015003 (4pp) | null | null | quant-ph | null | In the present article, we describe a method of introducing the harmonic
potential into the Klein-Gordon equation, leading to genuine bound states. The
eigenfunctions and eigenenergies are worked out explicitly.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 13:54:31 GMT"
},
{
"version": "v2",
"created": "Tue, 17 Apr 2007 17:17:06 GMT"
}
] | 2008-11-06T00:00:00 | [
[
"Rao",
"Nagalakshmi A",
""
],
[
"Kagali",
"B. A.",
""
]
] |
0704.1870 | Rochal Serguei | A.E.Myasnikova, E.N. Myasnikov | Band in ARPES caused by photodissociation of Landau-Pekar polarons | 8 pages, 6 figures | null | null | null | cond-mat.supr-con cond-mat.other | null | We consider decay of phonon condensate into phonons at photodissociation of
the strong coupling large polaron (SCLP), when the charge carrier becomes free.
Expression to calculate the band in ARPES caused by photodissociation of SCLP
is obtained. The band in ARPES caused by photodissociation of strong-coupling
large-radius polarons is a broad band with the shape determined by Poisson
distribution. It can be structured or unstructured depending on the phonon
dispersion since a distance between neighbouring lines comprising the band is
the phonon energy. Half-width of the band is in the interval 1.3 - 1.7Ep,
depending on the phonon energy. The band maximum is situated approximately at
the electron energy Ephot-W-3.2Ep (where Ephot is the photon energy, W is work
function), and its position does not depend on the electron wave vector
direction.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 14:02:37 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Myasnikova",
"A. E.",
""
],
[
"Myasnikov",
"E. N.",
""
]
] |
0704.1871 | Andres Balaguera | A. Balaguera-Antolinez, M. Nowakowski | From Global to Local Dynamics: Effects of the Expansion on Astrophysical
Structures | References added To be published in CQG | Class.Quant.Grav.24:2677-2688,2007 | 10.1088/0264-9381/24/10/013 | null | gr-qc | null | We explore the effects of background cosmology on large scale structures with
non-spherical symmetry by using the concept of quasi-equilibrium which allows
certain internal properties (e.g. angular velocity) of the bodies to change
with time. In accordance with the discovery of the accelerated phase of the
universe we model the cosmological background by two representative models: the
$\Lambda$CDM Model and the Chaplygin Gas Model. We compare the effects of the
two models on various properties of large astrophysical objects. Different
equations of state are also invoked in the investigation.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 16:49:41 GMT"
},
{
"version": "v2",
"created": "Tue, 17 Apr 2007 16:37:47 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Balaguera-Antolinez",
"A.",
""
],
[
"Nowakowski",
"M.",
""
]
] |
0704.1872 | Vladimir Kozhevnikov | V.F. Kozhevnikov, C.V. Giuraniuc, M.J. Van Bael, K. Temst, C. Van
Haesendonck, T.M. Mishonov, T. Charlton, R.M. Dalgliesh, Yu.N. Khaidukov,
Yu.V. Nikitenko, V.L. Aksenov, V.N. Gladilin, V.M. Fomin, J.T. Devreese, and
J.O. Indekeu | Evidence for nonmonotonic magnetic field penetration in a type-I
superconductor | 5 pages, 4 figures, LaTex, corrected typos and figures | null | 10.1103/PhysRevB.78.012502 | null | cond-mat.supr-con | null | Polarized neutron reflectometry (PNR) provides evidence that nonlocal
electrodynamics governs the magnetic field penetration in an extreme low-k
superconductor. The sample is an indium film with a large elastic mean free
path (11 mkm) deposited on a silicon oxide wafer. It is shown that PNR can
resolve the difference between the reflected neutron spin asymmetries predicted
by the local and nonlocal theories of superconductivity. The experimental data
support the nonlocal theory, which predicts a nonmonotonic decay of the
magnetic field.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 15:18:59 GMT"
},
{
"version": "v2",
"created": "Thu, 6 Dec 2007 02:23:27 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kozhevnikov",
"V. F.",
""
],
[
"Giuraniuc",
"C. V.",
""
],
[
"Van Bael",
"M. J.",
""
],
[
"Temst",
"K.",
""
],
[
"Van Haesendonck",
"C.",
""
],
[
"Mishonov",
"T. M.",
""
],
[
"Charlton",
"T.",
""
],
[
"Dalgliesh",
"R. M.",
""
],
[
"Khaidukov",
"Yu. N.",
""
],
[
"Nikitenko",
"Yu. V.",
""
],
[
"Aksenov",
"V. L.",
""
],
[
"Gladilin",
"V. N.",
""
],
[
"Fomin",
"V. M.",
""
],
[
"Devreese",
"J. T.",
""
],
[
"Indekeu",
"J. O.",
""
]
] |
0704.1873 | Yi Cao | Yi Cao and Biao Chen | An Achievable Rate Region for Interference Channels with Conferencing | 5 pages, 2 figures, accepted by ISIT'07 | null | null | null | cs.IT math.IT | null | In this paper, we propose an achievable rate region for discrete memoryless
interference channels with conferencing at the transmitter side. We employ
superposition block Markov encoding, combined with simultaneous superposition
coding, dirty paper coding, and random binning to obtain the achievable rate
region. We show that, under respective conditions, the proposed achievable
region reduces to Han and Kobayashi achievable region for interference
channels, the capacity region for degraded relay channels, and the capacity
region for the Gaussian vector broadcast channel. Numerical examples for the
Gaussian case are given.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 15:42:44 GMT"
}
] | 2007-07-13T00:00:00 | [
[
"Cao",
"Yi",
""
],
[
"Chen",
"Biao",
""
]
] |
0704.1874 | Alexei Popov | Alexei V. Popov and Vladimir V. Kopeikin | Electromagnetic Pulse Propagation over Nonuniform Earth Surface:
Numerical Simulation | null | null | null | null | math.NA math-ph math.MP | null | We simulate EM pulse propagation along the nonuniform earth surface using so
called time-domain parabolic equation. To solve it by finite differences, we
introduce a time-domain analog of the impedance boundary condition and a
nonlocal BC of transparency reducing open computational domain to a strip of
finite width. Numerical examples demonstrate influence of soil conductivity on
the wide-band pulse waveform. For a high-frequency modulated EM pulse, we
develop an asymptotic approach based on the ray structure of the monochromatic
wave field at carrier frequency. This radically diminishes the computation
costs and allows for pulsed wave field calculation in vast domains measured by
tens of thousands wavelengths.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 15:50:54 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Popov",
"Alexei V.",
""
],
[
"Kopeikin",
"Vladimir V.",
""
]
] |
0704.1875 | Gianluca Fiori | G. Fiori and G. Iannaccone | Simulation of Graphene Nanoribbon Field Effect Transistors | null | IEEE Electron Device Letters, Vol. 28, Issue 8, pp. 760 - 762,
2007 | 10.1109/LED.2007.901680 | null | cond-mat.mes-hall | null | We present an atomistic three-dimensional simulation of graphene nanoribbon
field effect transistors (GNR-FETs), based on the self-consistent solution of
the 3D Poisson and Schroedinger equation with open boundary conditions within
the non-equilibrium Green's Function formalism and a tight-binding hamiltonian.
With respect to carbon nanotube FETs, GNR-FETs exhibit comparable performance,
reduced sensitivity on the variability of channel chirality, and similar
leakage problems due to band-to-band tunneling. Acceptable transistor
performance requires effective nanoribbon width of 1-2 nm, that could be
obtained with periodic etching patterns or stress patterns.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 16:07:49 GMT"
},
{
"version": "v2",
"created": "Mon, 7 Jan 2008 11:43:30 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Fiori",
"G.",
""
],
[
"Iannaccone",
"G.",
""
]
] |
0704.1876 | Scott Funkhouser | Scott Funkhouser | Stars and the holographic upper bound on gravitational action | 2 pages | null | null | null | physics.gen-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The holographic upper bound on entropy is applied to the gravitational action
associated with the non-relativistic contraction of a nebula. A critical radius
is identified, as a function of the initial radius and mass, for which the
number of bits associated with the action would equal the maximum number of
bits allowed to the body. The gravitational action of a typical star
approximately saturates the holographic bound, perhaps suggesting a physical
link between holographic principles and astrophysical processes.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 16:23:57 GMT"
},
{
"version": "v2",
"created": "Sat, 21 Apr 2007 20:02:46 GMT"
},
{
"version": "v3",
"created": "Mon, 22 Dec 2008 18:34:16 GMT"
}
] | 2008-12-22T00:00:00 | [
[
"Funkhouser",
"Scott",
""
]
] |
0704.1877 | Stephen Doty | Stephen Doty | New versions of Schur-Weyl duality | Preprint from 2003 | null | null | null | math.RT | null | After reviewing classical Schur-Weyl duality, we present some other contexts
which enjoy similar features, relating to Brauer algebras and classical groups.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 16:29:41 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Doty",
"Stephen",
""
]
] |
0704.1878 | John D. Weeks | Jeng-Da Chai and John D Weeks | Orbital-Free Density Functional Theory: Kinetic Potentials and Ab-Initio
Local Pseudopotentials | To be published in Phys. Rev. B | null | 10.1103/PhysRevB.75.205122 | null | cond-mat.str-el cond-mat.mtrl-sci | null | In the density functional (DF) theory of Kohn and Sham, the kinetic energy of
the ground state of a system of noninteracting electrons in a general external
field is calculated using a set of orbitals. Orbital free methods attempt to
calculate this directly from the electron density by approximating the
universal but unknown kinetic energy density functional. However simple local
approximations are inaccurate and it has proved very difficult to devise
generally accurate nonlocal approximations. We focus instead on the kinetic
potential, the functional derivative of the kinetic energy DF, which appears in
the Euler equation for the electron density. We argue that the kinetic
potential is more local and more amenable to simple physically motivated
approximations in many relevant cases, and describe two pathways by which the
value of the kinetic energy can be efficiently calculated. We propose two
nonlocal orbital free kinetic potentials that reduce to known exact forms for
both slowly varying and rapidly varying perturbations and also reproduce exact
results for the linear response of the density of the homogeneous system to
small perturbations. A simple and systematic approach for generating accurate
and weak ab-initio local pseudopotentials which produce a smooth slowly varying
valence component of the electron density is proposed for use in orbital free
DF calculations of molecules and solids. The use of these local
pseudopotentials further minimizes the possible errors from the kinetic
potentials. Our theory yields results for the total energies and ionization
energies of atoms, and for the shell structure in the atomic radial density
profiles that are in very good agreement with calculations using the full
Kohn-Sham theory.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 16:31:36 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Chai",
"Jeng-Da",
""
],
[
"Weeks",
"John D",
""
]
] |
0704.1879 | Johan Andersson | Johan Andersson | Lower bounds in some power sum problems | 9 pages | null | null | null | math.NT | null | We study the power sum problem max_{v=1,...,m} | sum_{k=1}^n z_k^v | and by
using features of Fejer kernels we give new lower bounds in the case of
unimodular complex numbers z_k and m cn^2 for constants c>1.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 09:36:09 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Andersson",
"Johan",
""
]
] |
0704.1880 | Pasquale Calabrese | Pasquale Calabrese, John Cardy | Quantum Quenches in Extended Systems | 24 Pages, 4 figures | J.Stat.Mech.0706:P06008,2007 | 10.1088/1742-5468/2007/06/P06008 | null | cond-mat.stat-mech hep-th | null | We study in general the time-evolution of correlation functions in a extended
quantum system after the quench of a parameter in the hamiltonian. We show that
correlation functions in d dimensions can be extracted using methods of
boundary critical phenomena in d+1 dimensions. For d=1 this allows to use the
powerful tools of conformal field theory in the case of critical evolution.
Several results are obtained in generic dimension in the gaussian (mean-field)
approximation. These predictions are checked against the real-time evolution of
some solvable models that allows also to understand which features are valid
beyond the critical evolution.
All our findings may be explained in terms of a picture generally valid,
whereby quasiparticles, entangled over regions of the order of the correlation
length in the initial state, then propagate with a finite speed through the
system. Furthermore we show that the long-time results can be interpreted in
terms of a generalized Gibbs ensemble. We discuss some open questions and
possible future developments.
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 15:34:49 GMT"
},
{
"version": "v2",
"created": "Thu, 19 Apr 2007 13:36:26 GMT"
}
] | 2011-02-16T00:00:00 | [
[
"Calabrese",
"Pasquale",
""
],
[
"Cardy",
"John",
""
]
] |
0704.1881 | Brian Landry | Eric J. Heller and Brian R. Landry | Statistical Properties of Many Particle Eigenfunctions | 13 pages, 4 figures | null | 10.1088/1751-8113/40/31/006 | null | quant-ph | null | Wavefunction correlations and density matrices for few or many particles are
derived from the properties of semiclassical energy Green functions. Universal
features of fixed energy (microcanonical) random wavefunction correlation
functions appear which reflect the emergence of the canonical ensemble as the
number of particles approaches infinity. This arises through a little known
asymptotic limit of Bessel functions. Constraints due to symmetries,
boundaries, and collisions between particles can be included.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 16:43:25 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Heller",
"Eric J.",
""
],
[
"Landry",
"Brian R.",
""
]
] |
0704.1882 | Raissa M. D'Souza | Raissa M. D'Souza, Paul L. Krapivsky, Cristopher Moore | The power of choice in network growth | 9 pages, 4 figures | null | 10.1140/epjb/e2007-00310-5 | null | cond-mat.stat-mech | null | The "power of choice" has been shown to radically alter the behavior of a
number of randomized algorithms. Here we explore the effects of choice on
models of tree and network growth. In our models each new node has k randomly
chosen contacts, where k > 1 is a constant. It then attaches to whichever one
of these contacts is most desirable in some sense, such as its distance from
the root or its degree. Even when the new node has just two choices, i.e., when
k=2, the resulting network can be very different from a random graph or tree.
For instance, if the new node attaches to the contact which is closest to the
root of the tree, the distribution of depths changes from Poisson to a
traveling wave solution. If the new node attaches to the contact with the
smallest degree, the degree distribution is closer to uniform than in a random
graph, so that with high probability there are no nodes in the network with
degree greater than O(log log N). Finally, if the new node attaches to the
contact with the largest degree, we find that the degree distribution is a
power law with exponent -1 up to degrees roughly equal to k, with an
exponential cutoff beyond that; thus, in this case, we need k >> 1 to see a
power law over a wide range of degrees.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 17:23:05 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"D'Souza",
"Raissa M.",
""
],
[
"Krapivsky",
"Paul L.",
""
],
[
"Moore",
"Cristopher",
""
]
] |
0704.1883 | Junichiro Kono | X. Wang, D. J. Hilton, L. Ren, D. M. Mittleman, J. Kono, J. L. Reno | Terahertz Time-Domain Magnetospectroscopy of a High-Mobility
Two-Dimensional Electron Gas | 4 pages, 3 figures | Optics Letters 32, 13 (2007) | 10.1364/OL.32.001845 | null | cond-mat.mes-hall cond-mat.mtrl-sci | null | We have observed cyclotron resonance in a high-mobility GaAs/AlGaAs
two-dimensional electron gas by using the techniques of terahertz time-domain
spectroscopy combined with magnetic fields. From this, we calculate the real
and imaginary parts of the diagonal elements of the magnetoconductivity tensor,
which in turn allows us to extract the concentration, effective mass, and
scattering time of the electrons in the sample. We demonstrate the utility of
ultrafast terahertz spectroscopy, which can recover the true linewidth of
cyclotron resonance in a high-mobility ($>{10}^{6} \mathrm{cm^{2} V^{-1}
s^{-1}}$) sample without being affected by the saturation effect.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 18:21:01 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wang",
"X.",
""
],
[
"Hilton",
"D. J.",
""
],
[
"Ren",
"L.",
""
],
[
"Mittleman",
"D. M.",
""
],
[
"Kono",
"J.",
""
],
[
"Reno",
"J. L.",
""
]
] |
0704.1884 | Saka\'e Fuchino | J\"org Brendle and Saka\'e Fuchino | Coloring ordinals by reals | null | null | null | null | math.LO | null | We study combinatorial principles we call Homogeneity Principle HP(\kappa)
and Injectivity Principle IP(\kappa,\lambda) for regular \kappa>\aleph_1 and
\lambda\leq\kappa which are formulated in terms of coloring the ordinals
<\kappa by reals.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 18:41:56 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Brendle",
"Jörg",
""
],
[
"Fuchino",
"Sakaé",
""
]
] |
0704.1885 | Jesse Bloom | Jesse D. Bloom, Zhongyi Lu, David Chen, Alpan Raval, Ophelia S.
Venturelli, and Frances H. Arnold | Evolution favors protein mutational robustness in sufficiently large
populations | null | BMC Biology 5:29 (2007) | 10.1186/1741-7007-5-29 | null | q-bio.PE q-bio.BM | null | BACKGROUND: An important question is whether evolution favors properties such
as mutational robustness or evolvability that do not directly benefit any
individual, but can influence the course of future evolution. Functionally
similar proteins can differ substantially in their robustness to mutations and
capacity to evolve new functions, but it has remained unclear whether any of
these differences might be due to evolutionary selection for these properties.
RESULTS: Here we use laboratory experiments to demonstrate that evolution
favors protein mutational robustness if the evolving population is sufficiently
large. We neutrally evolve cytochrome P450 proteins under identical selection
pressures and mutation rates in populations of different sizes, and show that
proteins from the larger and thus more polymorphic population tend towards
higher mutational robustness. Proteins from the larger population also evolve
greater stability, a biophysical property that is known to enhance both
mutational robustness and evolvability. The excess mutational robustness and
stability is well described by existing mathematical theories, and can be
quantitatively related to the way that the proteins occupy their neutral
network.
CONCLUSIONS: Our work is the first experimental demonstration of the general
tendency of evolution to favor mutational robustness and protein stability in
highly polymorphic populations. We suggest that this phenomenon may contribute
to the mutational robustness and evolvability of viruses and bacteria that
exist in large populations.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 19:42:13 GMT"
}
] | 2009-04-16T00:00:00 | [
[
"Bloom",
"Jesse D.",
""
],
[
"Lu",
"Zhongyi",
""
],
[
"Chen",
"David",
""
],
[
"Raval",
"Alpan",
""
],
[
"Venturelli",
"Ophelia S.",
""
],
[
"Arnold",
"Frances H.",
""
]
] |
0704.1886 | Pedro Resende | S\'ergio Marcelino and Pedro Resende | An algebraic generalization of Kripke structures | 39 pages | Math. Proc. Cambridge Philos. Soc. 145 (2008) 549-577 | 10.1017/S0305004108001667 | null | math.LO cs.LO math.RA | null | The Kripke semantics of classical propositional normal modal logic is made
algebraic via an embedding of Kripke structures into the larger class of
pointed stably supported quantales. This algebraic semantics subsumes the
traditional algebraic semantics based on lattices with unary operators, and it
suggests natural interpretations of modal logic, of possible interest in the
applications, in structures that arise in geometry and analysis, such as
foliated manifolds and operator algebras, via topological groupoids and inverse
semigroups. We study completeness properties of the quantale based semantics
for the systems K, T, K4, S4, and S5, in particular obtaining an axiomatization
for S5 which does not use negation or the modal necessity operator. As
additional examples we describe intuitionistic propositional modal logic, the
logic of programs PDL, and the ramified temporal logic CTL.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 19:59:18 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Marcelino",
"Sérgio",
""
],
[
"Resende",
"Pedro",
""
]
] |
0704.1887 | Vladimir Matic Milan | V. M. Matic and N. Dj. Lazarov | Origin of the 60K plateau in YBa_2Cu_3O_6+x | 5 pages of text, 3 figures, corrected two typing errors: in paragraph
1 of page 2 "p(x)=0.94 - replaced by p(x)=0.094", in paragraph 2 of page 5
"2/3 - replaced by 2/5". Accepted for publication in Journal of Physics
Condensed Matter in a revised form (one page added to provide some more
informations on length distributions of CuO chains and some references added) | J. Phys.: Condens. Matter 19 (2007) 346230 | 10.1088/0953-8984/19/34/346230 | null | cond-mat.supr-con | null | A model for charge transfer mechanism in YBa2Cu3O6+x high-Tc cuprate based on
critical chain length concept is proposed to account for 60K and 90K plateaus
in Tc(x) dependence. It has been shown, when the statistics of CuO chain
formation was described in terms of two dimensional asymmetric next-to-nearest
neighbor Ising (ASYNNNI) model, that at any constant temperature below the top
of OII phase there exists a uniquely defined value of critical chain length
lcr(T) that yields a constant doping p(x)=const over the regime of OII phase
(related to 60K plateau of Tc(x)), while 90K plateau coincides with the
monotonously increasing p(x) over optimal doping level p=0.16 in the regime of
OI phase. Short length chains (l<lcr(T)), together with the first lcr(T)-2
holes in longer chains (l>lcr(T)), are taken as not capable of attracting
electrons from CuO2 planes.. It is shown that only a part (41%) of the
remaining l-lcr(T)+1 holes in the long chains can capture electrons. The
results obtained indicate that the ASYNNNI model and two-plateaus-like behavior
of Tc(x) in YBa2Cu3O6+x are closely connected.
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 20:17:27 GMT"
},
{
"version": "v2",
"created": "Fri, 20 Apr 2007 09:22:12 GMT"
},
{
"version": "v3",
"created": "Fri, 27 Apr 2007 11:11:56 GMT"
},
{
"version": "v4",
"created": "Thu, 5 Jul 2007 23:34:56 GMT"
}
] | 2007-08-15T00:00:00 | [
[
"Matic",
"V. M.",
""
],
[
"Lazarov",
"N. Dj.",
""
]
] |
0704.1888 | Martin Lorenz | Phung Ho Hai, Benoit Kriegk and Martin Lorenz | N-homogeneous superalgebras | 42 pages, LaTeX; typos corrected, several references added,
introduction slightly expanded | null | null | null | math.QA math.CO | null | We develop the theory of N-homogeneous algebras in a super setting, with
particular emphasis on the Koszul property. To any Hecke operator on a vector
superspace, we associate certain superalgebras and generalizing the ordinary
symmetric and Grassmann algebra, respectively. We prove that these algebras are
N-Koszul. For the special case where the Hecke operator is the ordinary
supersymmetry, we derive an $N$-generalized super-version of MacMahon's
classical "master theorem".
| [
{
"version": "v1",
"created": "Sat, 14 Apr 2007 22:58:58 GMT"
},
{
"version": "v2",
"created": "Mon, 4 Jun 2007 21:16:31 GMT"
}
] | 2007-06-13T00:00:00 | [
[
"Hai",
"Phung Ho",
""
],
[
"Kriegk",
"Benoit",
""
],
[
"Lorenz",
"Martin",
""
]
] |
0704.1889 | Qijin Chen | Yan He, Qijin Chen, Chih-Chun Chien, and K. Levin | First and second sound modes at finite temperature in trapped Fermi
gases from BCS to BEC | 4 pages, 3 figures, replaced with revised version | Phys. Rev. A 76, 051602(R) (2007) | 10.1103/PhysRevA.76.051602 | null | cond-mat.str-el cond-mat.quant-gas cond-mat.supr-con | null | We determine the temperature $T$ dependence of first and second sound mode
frequencies for trapped Fermi gases undergoing BCS to Bose Einstein
condensation (BEC) crossover. Our results are based on the two fluid equations
in conjunction with a microscopic calculation of thermodynamical variables. As
in experiment and at unitarity, we show that the lowest radial breathing mode
is $T$ independent. At finite $T$, higher order breathing modes strongly mix
with second sound. Their complex $T$ dependence should provide an alternative
way of measuring the transition temperature, $T_c$.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 00:02:39 GMT"
},
{
"version": "v2",
"created": "Mon, 16 Jul 2007 07:25:49 GMT"
}
] | 2011-09-13T00:00:00 | [
[
"He",
"Yan",
""
],
[
"Chen",
"Qijin",
""
],
[
"Chien",
"Chih-Chun",
""
],
[
"Levin",
"K.",
""
]
] |
0704.1890 | Alejandro Rodriguez | Alejandro Rodriguez, Mihai Ibanescu, Davide Iannuzzi, Federico
Capasso, John D. Joannopoulos, and Steven G. Johnson | Computation and visualization of Casimir forces in arbitrary geometries:
non-monotonic lateral forces and failure of proximity-force approximations | Accepted for publication in Physical Review Letters. (Expected
publication: Vol. 99 (8) 2007) | Physical Review Letters, Vol. 99, No. 8, 80401 (2007) | 10.1103/PhysRevLett.99.080401 | null | physics.comp-ph physics.optics quant-ph | null | We present a method of computing Casimir forces for arbitrary geometries,
with any desired accuracy, that can directly exploit the efficiency of standard
numerical-electromagnetism techniques. Using the simplest possible
finite-difference implementation of this approach, we obtain both agreement
with past results for cylinder-plate geometries, and also present results for
new geometries. In particular, we examine a piston-like problem involving two
dielectric and metallic squares sliding between two metallic walls, in two and
three dimensions, respectively, and demonstrate non-additive and non-monotonic
changes in the force due to these lateral walls.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 00:49:15 GMT"
},
{
"version": "v2",
"created": "Wed, 18 Apr 2007 02:19:28 GMT"
},
{
"version": "v3",
"created": "Wed, 8 Aug 2007 03:35:09 GMT"
},
{
"version": "v4",
"created": "Thu, 9 Aug 2007 05:43:32 GMT"
}
] | 2011-01-25T00:00:00 | [
[
"Rodriguez",
"Alejandro",
""
],
[
"Ibanescu",
"Mihai",
""
],
[
"Iannuzzi",
"Davide",
""
],
[
"Capasso",
"Federico",
""
],
[
"Joannopoulos",
"John D.",
""
],
[
"Johnson",
"Steven G.",
""
]
] |
0704.1891 | P. Christopher Staecker | P. Christopher Staecker | Axioms for a local Reidemeister trace in fixed point and coincidence
theory on differentiable manifolds | minor changes, synchronized with publication version | Journal of Fixed Point Theory and Applications 5, 2009, p. 237-247 | 10.1007/s11784-008-0055-8 | null | math.GT math.GN | null | We give axioms which characterize the local Reidemeister trace for orientable
differentiable manifolds. The local Reidemeister trace in fixed point theory is
already known, and we provide both uniqueness and existence results for the
local Reidemeister trace in coincidence theory.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 01:04:09 GMT"
},
{
"version": "v2",
"created": "Fri, 9 May 2008 18:59:26 GMT"
}
] | 2010-06-03T00:00:00 | [
[
"Staecker",
"P. Christopher",
""
]
] |
0704.1892 | Donald Barnes | Donald W. Barnes | On (n+2)-dimensional n-Lie algebras | 2 pages | null | null | null | math.RA | null | I show that an (n+2)-dimensional n-Lie algebra over an algebraically closed
field must have a subalgeba of codimension 1.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 01:41:47 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Barnes",
"Donald W.",
""
]
] |
0704.1893 | Elnikova Liliya V | L. V. Elnikova | Elastic properties of vanadium pentoxide aggregates and topological
defects | original title was "The junction of tactoids in lyotropic inorganic
liquid crystals" final form | null | null | null | cond-mat.soft | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the aqueous solution of vanadium pentoxide by using topology
methods. The experiments by Zocher, Kaznacheev, and Dogic exhibited, that in
the sol phases of $V_2O_5-H_2O$, the tactoid droplets of $V_2O_5$ can coalesce.
In the magnetic field, this effect is associated with a gauge field action,
viz. we consider coalescence (in the topologically more convenient term,
"junction") of droplets as annihilation of topological defects, concerning with
the tactoid geometry. We have shown, that in the magnetic field, the tactoid
junction is mainly caused by non-Abelian monopoles (vortons), whereas the
Abelian defects almost do not annihilate. Taking into account this annihilation
mechanism, the estimations of time-aging of the $V_2O_5-H_2O$ sols may be
specified
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 05:20:32 GMT"
},
{
"version": "v2",
"created": "Tue, 1 May 2007 13:51:59 GMT"
},
{
"version": "v3",
"created": "Sat, 14 Jul 2007 18:22:58 GMT"
},
{
"version": "v4",
"created": "Fri, 6 Jun 2008 15:09:19 GMT"
},
{
"version": "v5",
"created": "Wed, 13 Aug 2008 21:07:18 GMT"
},
{
"version": "v6",
"created": "Sat, 20 Sep 2008 14:57:16 GMT"
},
{
"version": "v7",
"created": "Fri, 7 Nov 2008 21:01:02 GMT"
}
] | 2008-11-07T00:00:00 | [
[
"Elnikova",
"L. V.",
""
]
] |
0704.1894 | Mushfiq Ahmad Mr. | Mushfiq Ahmad and M. Shah Alam | Non-Associativity of Lorentz Transformation and Associative Reflection
Symmetric Transformation | 4 pages, 1 figure | null | null | null | math-ph math.MP | null | Each of the two moving observers observes the relative velocity of the other.
The two velocities should be equal and opposite. We have shown that this
relativistic requirement is not fulfilled by Lorentz transformation. We have
also shown that the reason is that Lorentz transformation is not associative.
Reciprocal symmetric transformation is associative and fulfills relativistic
requirements.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 05:48:05 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Ahmad",
"Mushfiq",
""
],
[
"Alam",
"M. Shah",
""
]
] |
0704.1895 | Supurna Sinha | Supurna Sinha | Jamming dynamics in grain mixtures : An extended hydrodynamic approach | To appear in ``Fluctuation and Noise Letters'' | Fluctuation and Noise Letters, Vol. 7, No. 2 (2007), L163-L167 | null | null | cond-mat.soft | null | We study jamming in granular mixtures from the novel point of view of
extended hydrodynamics. Using a hard sphere binary mixture model we predict
that a few large grains are expected to get caged more effectively in a matrix
of small grains compared to a few small grains in a matrix of larger ones. A
similar effect has been experimentally seen in the context of colloidal
mixtures.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 07:06:12 GMT"
}
] | 2011-11-09T00:00:00 | [
[
"Sinha",
"Supurna",
""
]
] |
0704.1896 | Berthold-Georg Englert | Christian Miniatura, Cord A. M\"uller, Yin Lu, Guangquan Wang,
Berthold-Georg Englert | Path Distinguishability in Double Scattering of Light by Atoms | 4 pages, 1 figure; version 2: address correction | Physical Review A 76 (2007) 022101 (4 pages) | 10.1103/PhysRevA.76.022101 | null | quant-ph | null | Wave-particle duality finds a natural application for electrons or light
propagating in disordered media where coherent corrections to transport are
given by two-wave interference. For scatterers with internal degrees of
freedom, these corrections are observed to be much smaller than would be
expected for structureless scatterers. By examining the basic example of the
scattering of one photon by two spin-1/2 atoms--a case-study for coherent
backscattering--we demonstrate that the loss of interference strength is
associated with which-path information stored by the scattering atoms.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 07:26:51 GMT"
},
{
"version": "v2",
"created": "Tue, 17 Apr 2007 23:43:32 GMT"
}
] | 2011-03-15T00:00:00 | [
[
"Miniatura",
"Christian",
""
],
[
"Müller",
"Cord A.",
""
],
[
"Lu",
"Yin",
""
],
[
"Wang",
"Guangquan",
""
],
[
"Englert",
"Berthold-Georg",
""
]
] |
0704.1897 | Sergei Zhukovsky | S. V. Zhukovsky, S. V. Gaponenko | Constraints on transmission, dispersion, and density of states in
dielectric multilayers and stepwise potential barriers with arbitrary layer
arrangement | 10 pages, 5 figures, to be submitted to PRE | Phys. Rev. E 77, 046602 (2008) | 10.1103/PhysRevE.77.046602 | null | cond-mat.mes-hall physics.optics | null | Normal-incidence transmission and dispersion properties of optical
multilayers and one-dimensional stepwise potential barriers in the
non-tunneling regime are analytically investigated. The optical paths of every
constituent layer in a multilayer structure, as well as the parameters of every
step of the stepwise potential barrier, are constrained by a generalized
quarter-wave condition. No other restrictions on the structure geometry is
imposed, i.e., the layers are arranged arbitrarily. We show that the density of
states (DOS) spectra of the multilayer or barrier in question are subject to
integral conservation rules similar to the Barnett-Loudon sum rule but ocurring
within a finite frequency or energy interval. In the optical case, these
frequency intervals are regular. For the potential barriers, only non-periodic
energy intervals can be present in the spectrum of any given structure, and
only if the parameters of constituent potential steps are properly chosen.
Abstract The integral conservation relations derived analytically have also
been verified numerically. The relations can be used in dispersion-engineered
multilayer-based devices, e.g., ultrashort pulse compressors or ultracompact
optical delay lines, as well as to design multiple-quantum-well electronic
heterostructures with engineered DOS.
| [
{
"version": "v1",
"created": "Mon, 16 Apr 2007 17:16:07 GMT"
},
{
"version": "v2",
"created": "Fri, 14 Mar 2008 15:10:07 GMT"
}
] | 2008-04-13T00:00:00 | [
[
"Zhukovsky",
"S. V.",
""
],
[
"Gaponenko",
"S. V.",
""
]
] |
0704.1898 | Saharian | A.A. Saharian | Electromagnetic Casimir densities for a wedge with a coaxial cylindrical
shell | 21 pages, 7 figures | Eur.Phys.J.C52:721-733,2007 | 10.1140/epjc/s10052-007-0409-1 | null | hep-th quant-ph | null | Vacuum expectation values of the field square and the energy-momentum tensor
for the electromagnetic field are investigated for the geometry of a wedge with
a coaxal cylindrical boundary. All boundaries are assumed to be perfectly
conducting and both regions inside and outside the shell are considered. By
using the generalized Abel-Plana formula, the vacuum expectation values are
presented in the form of the sum of two terms. The first one corresponds to the
geometry of the wedge without the cylindrical shell and the second term is
induced by the presence of the shell. The vacuum energy density induced by the
shell is negative for the interior region and is positive for the exterior
region. The asymptotic behavior of the vacuum expectation values are
investigated in various limiting cases. It is shown that the vacuum forces
acting on the wedge sides due to the presence of the cylindrical boundary are
always attractive.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 10:53:31 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Saharian",
"A. A.",
""
]
] |
0704.1899 | Andrew Levan | Melvyn B. Davies, Andrew J. Levan, Josefin Larsson, Andrew R. King,
Andrew S. Fruchter | Progenitors of Long Gamma-ray Bursts | To appear in "Gamma-ray bursts: Prospects for GLAST", AIP Conference
proceedings 906, Editors M. Axelsson and F Ryde | AIP Conf.Proc.906:69-78,2007 | 10.1063/1.2737408 | null | astro-ph | null | Pinpointing the progenitors of long duration gamma-ray bursts (LGRBs) remains
an extremely important question, although it is now clear that at least a
fraction of LGRBs originate in the core collapse of massive stars in type Ic
supernovae, the pathways to the production of these stars, and their initial
masses, remain uncertain. Rotation is thought to be vital in the creation of
LGRBs, and it is likely that black hole creation is also necessary. We suggest
that these two constraints can be met if the GRB progenitors are very massive
stars (>20 solar masses) and are formed in tight binary systems. Using simple
models we compare the predictions of this scenario with observations and find
that the location of GRBs on their host galaxies are suggestive of
main-sequence masses in excess of 20 solar masses, while 50% of the known
compact binary systems may have been sufficiently close to have had the
necessary rotation rates for GRB creation. Thus, massive stars in compact
binaries are a likely channel for at least some fraction of LGRBs.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 11:54:27 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Davies",
"Melvyn B.",
""
],
[
"Levan",
"Andrew J.",
""
],
[
"Larsson",
"Josefin",
""
],
[
"King",
"Andrew R.",
""
],
[
"Fruchter",
"Andrew S.",
""
]
] |
0704.1900 | Luca Vecchi | Luca Vecchi | Causal vs. Analytic constraints on anomalous quartic gauge couplings | 4 pages, non forward scattering included, references added | JHEP 0711:054,2007 | 10.1088/1126-6708/2007/11/054 | null | hep-ph | null | We derive one loop constraints on the anomalous quartic gauge couplings using
a general non-forward dispersion relation for the elastic scattering amplitude
of two longitudinally polarized vector bosons. We compare this result with
another one derived by the assumption that the underlying theory satisfies the
causality principle of Special Relativity and show that this latter is more
constraining.
| [
{
"version": "v1",
"created": "Sun, 15 Apr 2007 14:23:13 GMT"
},
{
"version": "v2",
"created": "Fri, 29 Jun 2007 11:43:47 GMT"
},
{
"version": "v3",
"created": "Thu, 15 Nov 2007 14:52:46 GMT"
}
] | 2009-04-21T00:00:00 | [
[
"Vecchi",
"Luca",
""
]
] |
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