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| versions
list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0705.2798 | Choon-Lin Ho | Choon-Lin Ho, Yan-Min Dai | A perturbative approach to a class of Fokker-Planck equations | 5 pages, no figures | null | 10.1142/S0217984908015000 | null | math-ph cond-mat.other math.AP math.MP | null | In this paper we present a direct perturbative method to solving certain
Fokker-Planck equations, which have constant diffusion coefficients and some
small parameters in the drift coefficients. The method makes use of the
connection between the Fokker-Planck and Schr\"odinger equations. Two examples
are used to illustrate the method. In the first example the drift coefficient
depends only on time but not on space. In the second example we consider the
Uhlenbeck-Ornstein process with a small drift coefficient. These examples show
that the such perturbative approach can be a useful tool to obtain approximate
solutions of Fokker-Planck equations with constant diffusion coefficients.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 06:49:58 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Ho",
"Choon-Lin",
""
],
[
"Dai",
"Yan-Min",
""
]
] |
0705.2799 | Takeshi Saito | Takeshi Saito | Wild ramification and the characteristic cycle of an l-adic sheaf | 56 pages | Journal of the Institute of Mathematics of Jussieu (2009), 8 :
769-829 | 10.1017/S1474748008000364 | null | math.AG | null | We propose a geometric method to measure the wild ramification of a smooth
etale sheaf along the boundary. Using the method, we study the graded quotients
of the logarithmic ramification groups of a local field of positive
characteristic with arbitrary residue field. We also define the characteristic
cycle of an l-adic sheaf, satisfying certain conditions, as a cycle on the
logarithmic cotangent bundle and prove that the intersection with the 0-section
computes the characteristic class, and hence the Euler number.
Definition 2.1.1 is corrected in v2.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 07:29:55 GMT"
},
{
"version": "v2",
"created": "Fri, 1 Feb 2008 01:35:31 GMT"
}
] | 2010-05-18T00:00:00 | [
[
"Saito",
"Takeshi",
""
]
] |
0705.2800 | Nicolas Prudhon | N. Prudhon | Maximal hypoellipticity and Dolbeault cohomology representations for
U(p,q) | 14 pages, preprint, LaTeX | null | null | null | math.RT math.DG | null | Let Y=G/L be a flag manifold for a reductive G and K a maximal compact
subgroup of G. We define an equivariant differential operator on G/(L cap K)
playing the role of an equivariant Dolbeault Laplacian when restricted to the
complex manifold G/L, using a distribution transverse to the fibers and
satisfying the Hormander condition. We prove here that this operator is not
maximal hypoelliptic when G=U(p,q).
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 07:45:38 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Prudhon",
"N.",
""
]
] |
0705.2801 | Simonetta Gentile | S. Gentile, H. Bilokon, V. Chiarella, G. Nicoletti | The ATLAS discovery potential for MSSM neutral Higgs bosons decaying to
a mu+mu- pair in the mass range up to 130 GeV | null | Eur.Phys.J.C52:229-245,2007 | 10.1140/epjc/s10052-007-0373-9 | SN-ATLAS-2007-063 | hep-ex | null | Results are presented on the discovery potential for MSSM neutral Higgs
bosons in the Mh-{max}scenario. The region of large tan beta, between 15 and
50, and mass between ~ 95 and 130 GeV is considered in the framework of the
ATLAS experiment at the Large Hadron Collider (LHC), for a centre-of-mass
energy = 14 TeV. This parameter region is not fully covered by the present data
either from LEP or from Tevatron. The h/A bosons, supposed to be very close in
mass in that region, are studied in the channel h/A -> mu+mu- accompanied by
two b-jets. The study includes a method to control the most copious background,
Zo -> mu+mu- accompanied by two b-jets. A possible contribution of the H boson
to the signal is also considered.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 08:07:07 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Gentile",
"S.",
""
],
[
"Bilokon",
"H.",
""
],
[
"Chiarella",
"V.",
""
],
[
"Nicoletti",
"G.",
""
]
] |
0705.2802 | Ruiming Zhang Dr. | Ruiming Zhang | On Asymptotics of $q$-Gamma Functions | 10 pages | null | 10.1016/j.jmaa.2007.08.006 | null | math.CA math-ph math.MP | null | In this paper we derive some asymptotic formulas for the $q$-Gamma function
$\Gamma_{q}(z)$ for $q$ tending to 1.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 08:10:31 GMT"
},
{
"version": "v2",
"created": "Sat, 26 May 2007 01:18:02 GMT"
},
{
"version": "v3",
"created": "Thu, 26 Jul 2007 02:44:56 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Zhang",
"Ruiming",
""
]
] |
0705.2803 | Fabrice Silva | Fabrice Silva (LMA), Vincent Debut (ITN), Jean Kergomard (LMA),
Christophe Vergez (LMA), Aude Deblevid (LMA), Philippe Guillemain (LMA) | Simulation of Single Reed Instruments Oscillations Based on Modal
Decomposition of Bore and Reed Dynamics | null | null | null | null | physics.class-ph | null | This paper investigates the sound production in a system made of a bore
coupled with a reed valve. Extending previous work (Debut, 2004), the input
impedance of the bore is projected on the modes of the air column. The acoustic
pressure is therefore calculated as the sum of modal components. The
airrrflow blown into the bore is modulated by reed motion, assuming
the reed to be a single degree of freedom oscillator. Calculation of
self-sustained oscillations controlled by time-varying mouth pressure and
player's embouchure parameter is performed using ODE solvers. Results emphasize
the par ticipation of the whole set of components in the mode locking process.
Another impor tant feature is the mutual innnfluence of reed and
bore resonance during growing blowing pressure transients, oscillation
threshold being altered by the reed natural frequency and the reed damping.
Steady-state oscillations are also investigated and compared with results given
by harmonic balance method and by digital sound synthesis.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 08:21:45 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Silva",
"Fabrice",
"",
"LMA"
],
[
"Debut",
"Vincent",
"",
"ITN"
],
[
"Kergomard",
"Jean",
"",
"LMA"
],
[
"Vergez",
"Christophe",
"",
"LMA"
],
[
"Deblevid",
"Aude",
"",
"LMA"
],
[
"Guillemain",
"Philippe",
"",
"LMA"
]
] |
0705.2804 | Rodolfo Angeloni | R. Angeloni (1,2), M. Contini (2,1), S. Ciroi (1), P. Rafanelli (1)
((1) Dept. of Astronomy, University of Padova, Italy; (2) School of Physics
and Astronomy, Tel Aviv University, Israel) | Gas and dust spectra of the D' type symbiotic star HD330036 | 11 pages, 5 figures, accepted for publication in A&A on 10th May 2007 | null | 10.1051/0004-6361:20077324 | null | astro-ph | null | We present a comprehensive and self-consistent modelling of the D' type
symbiotic star (SS) HD330036 from radio to UV. Within a colliding-wind
scenario, we analyse the continuum, line and dust spectra by means of SUMA, a
code that simulates the physical conditions of an emitting gaseous cloud under
the coupled effect of ionization from an external radiation source and shocks.
We find that the UV lines are emitted from high density gas between the stars
downstream of the reverse shock, while the optical lines are emitted downstream
of the shock propagating outwards the system. As regards with the continuum
SED, three shells are identified in the IR, at 850K, 320 K and 200 K with radii
r = 2.8 10^13 cm, 4 10^14$ cm, and 10^15 cm, respectively, adopting a distance
to Earth d=2.3 kpc: interestingly, all these shells appear to be circumbinary.
The analysis of the unexploited ISO-SWS spectrum reveals that both PAHs and
crystalline silicates coexist in HD330036, with PAHs associated to the internal
shell at 850 K, and crystalline silicates stored into the cool shells at 320 K
and 200 K. Strong evidence that crystalline silicates are shaped in a disk-like
structure is derived on the basis of the relative band strengths. Finally, we
suggest that shocks can be a reliable mechanism in activating the annealing and
the consequent crystallization processes. We show that a consistent
interpretation of gas and dust spectra emitted by SS can be obtained by models
which accounts for the coupled effect of the photoionizing flux and of shocks.
The VLTI/MIDI proposal recently accepted by ESO aims to verify and better
constrain some of our results by means of IR interferometric observations.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 08:53:39 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Angeloni",
"R.",
""
],
[
"Contini",
"M.",
""
],
[
"Ciroi",
"S.",
""
],
[
"Rafanelli",
"P.",
""
]
] |
0705.2805 | Yong Su Kim | Yong Su Kim, D. J. Kim, T. H. Kim, and T. W. Noh, J. S. Choi and B. H.
Park, J.-G. Yoon | Observation of room-temperature ferroelectricity in tetragonal strontium
titanate thin films on SrTiO3 (001) substrates | null | Appl. Phys. Lett. 91 (2007) 042908 | 10.1063/1.2764437 | null | cond-mat.mtrl-sci | null | We investigated the ferroelectric properties of strontium titanate (STO) thin
films deposited on SrTiO3 (001) substrate with SrRuO3 electrodes. The STO layer
was grown coherently on the SrTiO3 substrate without in-plane lattice
relaxation, but its out-of-plane lattice constant increased with a decrease in
the oxygen pressure during deposition. Using piezoresponse force microscopy and
P-V measurements, we showed that our tetragonal STO films possess
room-temperature ferroelectricity. We discuss the possible origins of the
observed ferroelectricity.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 08:27:38 GMT"
},
{
"version": "v2",
"created": "Mon, 2 Jul 2007 04:24:49 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kim",
"Yong Su",
""
],
[
"Kim",
"D. J.",
""
],
[
"Kim",
"T. H.",
""
],
[
"Noh",
"T. W.",
""
],
[
"Choi",
"J. S.",
""
],
[
"Park",
"B. H.",
""
],
[
"Yoon",
"J. -G.",
""
]
] |
0705.2806 | JinLin Han | J. W. Xu (NAOC), J. L. Han (NAOC), X. H. Sun (NAOC, Mpifr), W. Reich
(MPIfR), L. Xiao (NAOC), P. Reich (MPIfR), R. Wielebinski (MPIfR) | Polarization observations of SNR G156.2+5.7 at lambda 6cm | 8 pages, 8 figures -- accepted by A&A | null | 10.1051/0004-6361:20077549 | null | astro-ph | null | G156.2+5.7 is a large supernova remnant (SNR) first discovered in the ROSAT
X-ray survey but radio observations are rare because of its low surface
brightness and large size. Radio continuum and polarization images of the SNR
G156.2+5.7 at lambda 6 cm are presented for the first time to be discussed in
the context with available data to investigate its physical properties. We
obtained an integrated flux density for G156.2+5.7 of S6cm= 2.5+-0.5Jy. The
spectral index of the integrated emission is alpha=-0.48+-0.08 between lambda
74 cm and 6 cm excluding compact radio sources. We also obtained a spectral
index map, which shows little variation between the shells and the central area
of the SNR. This is consistent with the constant integrated flux density
spectrum. Highly polarized radio emission has been detected from the SNR shell,
but also from a central patch, which probably originates in the front part of
the spherical SNR shell. We derived the distribution of rotation measure from
polarization data at 11 cm and 6 cm and found RM gradients of opposite
direction in the SNR shell. The SNR G156.2+5.7 is unusual by its exceptionally
high X-ray brightness and very low surface-brightness in the radio range. The
magnetic field is very well ordered along the shell periphery as expected for a
compressed ambient magnetic field. A toroidal magnetic field component is
indicated by the RM distribution. (abridged)
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 08:27:49 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Xu",
"J. W.",
"",
"NAOC"
],
[
"Han",
"J. L.",
"",
"NAOC"
],
[
"Sun",
"X. H.",
"",
"NAOC, Mpifr"
],
[
"Reich",
"W.",
"",
"MPIfR"
],
[
"Xiao",
"L.",
"",
"NAOC"
],
[
"Reich",
"P.",
"",
"MPIfR"
],
[
"Wielebinski",
"R.",
"",
"MPIfR"
]
] |
0705.2807 | Denis Krotov | Hyun Kwang Kim (Pohang University of Science and Technology, South
Korea), Denis Krotov (Sobolev Institute of Mathematics, Novosibirsk, Russia) | The poset metrics that allow binary codes of codimension m to be m-,
(m-1)-, or (m-2)-perfect | 6pp, 33fig. V2: revised | IEEE Trans. Inf. Theory 54(11) 2008, 5241-5246 | 10.1109/TIT.2008.929972 | null | math.CO cs.DM | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A binary poset code of codimension M (of cardinality 2^{N-M}, where N is the
code length) can correct maximum M errors. All possible poset metrics that
allow codes of codimension M to be M-, (M-1)- or (M-2)-perfect are described.
Some general conditions on a poset which guarantee the nonexistence of perfect
poset codes are derived; as examples, we prove the nonexistence of R-perfect
poset codes for some R in the case of the crown poset and in the case of the
union of disjoin chains. Index terms: perfect codes, poset codes
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 09:21:48 GMT"
},
{
"version": "v2",
"created": "Sun, 26 Oct 2008 09:49:06 GMT"
}
] | 2008-10-26T00:00:00 | [
[
"Kim",
"Hyun Kwang",
"",
"Pohang University of Science and Technology, South\n Korea"
],
[
"Krotov",
"Denis",
"",
"Sobolev Institute of Mathematics, Novosibirsk, Russia"
]
] |
0705.2808 | Rodolfo Angeloni | R. Angeloni (1,2), M. Contini (2,1), S. Ciroi (1), P. Rafanelli (1)
((1) Dept. of Astronomy, University of Padova, Italy; (2) School of Physics
and Astronomy, Tel Aviv University, Israel) | The symbiotic star H1-36. A composite model of line and continuum
spectra from radio to ultraviolet | 8 pages, 3 figures, 5 tables, accepted for publication in A&A on 2th
May 2007 | null | 10.1051/0004-6361:20077526 | null | astro-ph | null | In this paper we analyse the spectra of D-type SS H1-36 within a
colliding-wind scenario. We aim to analyse the properties of this object taking
into account the observational data along the whole electromagnetic spectrum,
in order to derive a self-consistent picture able to interpret the nature of
the system as a whole. After constraining the relative physical conditions by
modelling more than 40 emission lines from radio to UV, we are able to explain
the continuum spectral energy distribution by taking into account all the
emitting contributions arising from both the stars, the dust shells and the
gaseous nebulae. A comprehensive model of the radio spectra allows to reproduce
the different slopes of the radio profile and the turnover frequency, as well
as the different size of the observed shocked envelope at different frequencies
in the light of the different contributions from the expanding and reverse
nebulae. The IR continuum unveils the presence of two dust shells with
different radii and temperatures, which might be a distinctive feature of
D-type symbiotic systems as a class of objects. The broad profiles of IR lines
direct us to investigate whether an X-ray jet may be present. This insight
leads us to indicate H1-36 as a promising X-ray target and to encourage
observations and studies which consistently take into account the complex
nature of symbiotic stars throughout the whole electromagnetic spectrum.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 09:04:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Angeloni",
"R.",
""
],
[
"Contini",
"M.",
""
],
[
"Ciroi",
"S.",
""
],
[
"Rafanelli",
"P.",
""
]
] |
0705.2809 | Lars Mattsson | Lars Mattsson, Rurik Wahlin and Susanne Hoefner | Thresholds for the Dust Driven Mass Loss from C-rich AGB Stars | 2 pages, 1 figure. To be published in the proceedings of IAU Symp.
241 on Stellar Populations as Building Blocks of Galaxies, ed. A. Vazdekis et
al. (2007). Replaced to match edited version | null | 10.1017/S1743921307007375 | null | astro-ph | null | It is well established that mass loss from AGB stars due to dust driven winds
cannot be arbitrarily low. We model the mass loss from carbon rich AGB stars
using detailed frequency-dependent radiation hydrodynamics including dust
formation. We present a study of the thresholds for the mass loss rate as a
function of stellar parameters based on a subset of a larger grid of such
models and compare these results to previous observational and theoretical
work. Furthermore, we demonstrate the impact of the pulsation mechanism and
dust formation for the creation of a stellar wind and how it affects these
thresholds and briefly discuss the consequences for stellar evolution.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 09:10:15 GMT"
},
{
"version": "v2",
"created": "Wed, 13 Jun 2007 15:09:58 GMT"
}
] | 2019-08-19T00:00:00 | [
[
"Mattsson",
"Lars",
""
],
[
"Wahlin",
"Rurik",
""
],
[
"Hoefner",
"Susanne",
""
]
] |
0705.2810 | Enrico Priola | Enrico Priola | Global Schauder estimates for a class of degenerate Kolmogorov equations | null | null | null | null | math.AP | null | We consider a class of possibly degenerate second order elliptic operators
$\cal
A$ on $\R^n$. This class includes hypoelliptic
Ornstein-Uhlenbeck type operators having an additional first order term with
unbounded coefficients. We establish global Schauder estimates in H\"older
spaces both for elliptic equations and for parabolic Cauchy problems involving
${\cal A}$. The H\"older function spaces are defined with respect to a
non-euclidean metric related to the operator $\cal A$.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 10:27:16 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Priola",
"Enrico",
""
]
] |
0705.2811 | Alessandro Torcini | R\"udiger Zillmer, Roberto Livi, Antonio Politi, and Alessandro
Torcini | Stability of the splay state in pulse--coupled networks | 13 pages, 10 figures, submitted for pubblication to Physical Review E | Phys. Rev. E 76, 046102 (2007) | 10.1103/PhysRevE.76.046102 | null | cond-mat.dis-nn q-bio.NC | null | The stability of the dynamical states characterized by a uniform firing rate
({\it splay states}) is analyzed in a network of globally coupled leaky
integrate-and-fire neurons. This is done by reducing the set of differential
equations to a map that is investigated in the limit of large network size. We
show that the stability of the splay state depends crucially on the ratio
between the pulse--width and the inter-spike interval. More precisely, the
spectrum of Floquet exponents turns out to consist of three components: (i) one
that coincides with the predictions of the mean-field analysis [Abbott-van
Vreesvijk, 1993]; (ii) a component measuring the instability of
"finite-frequency" modes; (iii) a number of "isolated" eigenvalues that are
connected to the characteristics of the single pulse and may give rise to
strong instabilities (the Floquet exponent being proportional to the network
size). Finally, as a side result, we find that the splay state can be stable
even for inhibitory coupling.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 10:32:10 GMT"
}
] | 2007-11-27T00:00:00 | [
[
"Zillmer",
"Rüdiger",
""
],
[
"Livi",
"Roberto",
""
],
[
"Politi",
"Antonio",
""
],
[
"Torcini",
"Alessandro",
""
]
] |
0705.2812 | Arnab Bhattacharya | Abdul Kadir, Tapas Ganguli, Ravi Kumar, M.R. Gokhale, A.P. Shah,
Sandip Ghosh, B.M. Arora and Arnab Bhattacharya | The role of hydrostatic stress in determining the bandgap of InN
epilayers | Submitted to Appl. Phys. Lett | null | 10.1063/1.2784199 | null | cond-mat.mtrl-sci | null | We establish a correlation between the internal stress in InN epilayers and
their optical properties such as the measured absorption band edge and
photoluminescence emission wavelength. By a careful evaluation of the lattice
constants of InN epilayers grown on c-plane sapphire substrates under various
conditions by metalorganic vapor phase epitaxy we find that the films are under
primarily hydrostatic stress. This results in a shift in the band edge to
higher energy. The effect is significant, and may be responsible for some of
the variations in InN bandgap reported in the literature.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 11:08:32 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kadir",
"Abdul",
""
],
[
"Ganguli",
"Tapas",
""
],
[
"Kumar",
"Ravi",
""
],
[
"Gokhale",
"M. R.",
""
],
[
"Shah",
"A. P.",
""
],
[
"Ghosh",
"Sandip",
""
],
[
"Arora",
"B. M.",
""
],
[
"Bhattacharya",
"Arnab",
""
]
] |
0705.2813 | Rama Kant | Rama Kant | Theory of anomalous diffusive reaction rates on realistic self-affine
fractals | 10 pages, 3 figures, 1 table | null | null | null | physics.chem-ph | null | In this letter, a theoretical method for the analysis of diffusive
flux/current to limited scale self-affine random fractals is presented and
compared with experimentally measured electrochemical current for such
roughness. The theory explains the several experimental findings of the
temporal scale invariance as well as deviation from this of current transients
in terms of three dominant fractal parameters for the limited-length scales of
roughness. This theoretical method is based on limited scale power-law
characterization of the interfacial roughness spectrum and the solution of
diffusion equation under the diffusion-limited boundary conditions on rough
interfaces. More broadly, these calculations challenges the earlier belief that
the anomalous behavior is solely dependent on fractal dimension of roughness
and highlight the potential to apply this equation for the scale invariant
roughness determination. Finally, the validity of theoretical result is tested
with extensive experimental data.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 11:09:52 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kant",
"Rama",
""
]
] |
0705.2814 | Francois Rincon | F. Rincon, G. I. Ogilvie and M. R. E. Proctor (DAMTP, University of
Cambridge) | A self-sustaining nonlinear dynamo process in Keplerian shear flows | 4 pages, 7 figures, accepted for publication in Physical Review
Letters | Phys.Rev.Lett.98:254502,2007 | 10.1103/PhysRevLett.98.254502 | null | astro-ph physics.flu-dyn | null | A three-dimensional nonlinear dynamo process is identified in rotating plane
Couette flow in the Keplerian regime. It is analogous to the hydrodynamic
self-sustaining process in non-rotating shear flows and relies on the
magneto-rotational instability of a toroidal magnetic field. Steady nonlinear
solutions are computed numerically for a wide range of magnetic Reynolds
numbers but are restricted to low Reynolds numbers. This process may be
important to explain the sustenance of coherent fields and turbulent motions in
Keplerian accretion disks, where all its basic ingredients are present.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 11:58:43 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Rincon",
"F.",
"",
"DAMTP, University of\n Cambridge"
],
[
"Ogilvie",
"G. I.",
"",
"DAMTP, University of\n Cambridge"
],
[
"Proctor",
"M. R. E.",
"",
"DAMTP, University of\n Cambridge"
]
] |
0705.2815 | Dibyendu Roy | Dibyendu Roy, N.Kumar | Random-phase reservoir and a quantum resistor: The Lloyd model | 4 pages,5 figures | Phys. Rev. B 76, 092202 (2007) | 10.1103/PhysRevB.76.092202 | null | cond-mat.mes-hall cond-mat.dis-nn | null | We introduce phase disorder in a 1D quantum resistor through the formal
device of `fake channels' distributed uniformly over its length such that the
out-coupled wave amplitude is re-injected back into the system, but with a
phase which is random. The associated scattering problem is treated via
invariant imbedding in the continuum limit, and the resulting transport
equation is found to correspond exactly to the Lloyd model. The latter has been
a subject of much interest in recent years. This conversion of the random phase
into the random Cauchy potential is a notable feature of our work. It is
further argued that our phase-randomizing reservoir, as distinct from the well
known phase-breaking reservoirs, induces no decoherence, but essentially
destroys all interference effects other than the coherent back scattering.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 12:14:03 GMT"
},
{
"version": "v2",
"created": "Wed, 23 May 2007 16:03:15 GMT"
},
{
"version": "v3",
"created": "Sun, 16 Sep 2007 17:31:25 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Roy",
"Dibyendu",
""
],
[
"Kumar",
"N.",
""
]
] |
0705.2816 | Ginestra Bianconi | Ginestra Bianconi and Riccardo Zecchina | Viable flux distribution in metabolic networks | (10 pages, 1 figure) | null | null | null | q-bio.MN | null | The metabolic networks are very well characterized for a large set of
organisms, a unique case in within the large-scale biological networks. For
this reason they provide a a very interesting framework for the construction of
analytically tractable statistical mechanics models.
In this paper we introduce a solvable model for the distribution of fluxes in
the metabolic network. We show that the effect of the topology on the
distribution of fluxes is to allow for large fluctuations of their values, a
fact that should have implications on the robustness of the system.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 10:53:37 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bianconi",
"Ginestra",
""
],
[
"Zecchina",
"Riccardo",
""
]
] |
0705.2817 | George Harry Hitching | George H. Hitching and Trygve Johnsen | Decoding of scroll codes | 14 pages | null | null | null | math.AG | null | We define and study a class of codes obtained from scrolls over curves of any
genus over finite fields. These codes generalize Goppa codes in a natural way,
and the orthogonal complements of these codes belong to the same class. We show
how syndromes of error vectors correspond to certain vector bundle extensions,
and how decoding is associated to finding destabilizing subbundles.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 13:53:23 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hitching",
"George H.",
""
],
[
"Johnsen",
"Trygve",
""
]
] |
0705.2818 | Kirill A. Kazakov | Kirill A. Kazakov | Quantum Theory of Flicker Noise in Metal Films | 20 pages, 2 tables, 2 figures | null | 10.1016/j.physb.2007.12.005 | null | cond-mat.mes-hall | null | Flicker (1/f^gamma) voltage noise spectrum is derived from finite-temperature
quantum electromagnetic fluctuations produced by elementary charge carriers in
external electric field. It is suggested that deviations of the frequency
exponent \gamma from unity, observed in thin metal films, can be attributed to
quantum backreaction of the conducting medium on the fluctuating field of the
charge carrier. This backreaction is described phenomenologically in terms of
the effective momentum space dimensionality, D. Using the dimensional
continuation technique, it is shown that the combined action of the photon heat
bath and external field results in a 1/f^gamma-contribution to the spectral
density of the two-point correlation function of electromagnetic field. The
frequency exponent is found to be equal to 1 + delta, where delta = 3 - D is a
reduction of the momentum space dimensionality. This result is applied to the
case of a biased conducting sample, and a general expression for the voltage
power spectrum is obtained which possesses all characteristic properties of
observed flicker noise spectra. The range of validity of this expression covers
well the whole measured frequency band. Gauge independence of the power
spectrum is proved. It is shown that the obtained results naturally resolve the
problem of divergence of the total noise power. A detailed comparison with the
experimental data on flicker noise measurements in metal films is given.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 13:24:47 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kazakov",
"Kirill A.",
""
]
] |
0705.2819 | Preetam Patil | Preetam Patil, Varsha Apte (Department of CSE, IIT-Bombay, India) | An Autonomous Distributed Admission Control Scheme for IEEE 802.11 DCF | Submitted to QShine'07 | null | null | null | cs.NI cs.PF | null | Admission control as a mechanism for providing QoS requires an accurate
description of the requested flow as well as already admitted flows. Since
802.11 WLAN capacity is shared between flows belonging to all stations,
admission control requires knowledge of all flows in the WLAN. Further,
estimation of the load-dependent WLAN capacity through analytical model
requires inputs about channel data rate, payload size and the number of
stations. These factors combined point to a centralized admission control
whereas for 802.11 DCF it is ideally performed in a distributed manner. The use
of measurements from the channel avoids explicit inputs about the state of the
channel described above. BUFFET, a model based measurement-assisted distributed
admission control scheme for DCF proposed in this paper relies on measurements
to derive model inputs and predict WLAN saturation, thereby maintaining average
delay within acceptable limits. Being measurement based, it adapts to a
combination of data rates and payload sizes, making it completely autonomous
and distributed. Performance analysis using OPNET simulations suggests that
BUFFET is able to ensure average delay under 7ms at a near-optimal throughput.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 13:54:25 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Patil",
"Preetam",
"",
"Department of CSE, IIT-Bombay, India"
],
[
"Apte",
"Varsha",
"",
"Department of CSE, IIT-Bombay, India"
]
] |
0705.2820 | Yoichi Hirai | Yoichi Hirai (The University of Tokyo, undergraduate) | Entropy Oriented Trading: A Trading Strategy Based on the Second Law of
Thermodynamics | 3 pages | null | null | null | q-fin.TR physics.pop-ph physics.soc-ph | null | The author proposes a finance trading strategy named Entropy Oriented Trading
and apply thermodynamics on the strategy. The state variables are chosen so
that the strategy satisfies the second law of thermodynamics. Using the law,
the author proves that the rate of investment (ROI) of the strategy is equal to
or more than the rate of price change.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 10:26:48 GMT"
}
] | 2008-12-02T00:00:00 | [
[
"Hirai",
"Yoichi",
"",
"The University of Tokyo, undergraduate"
]
] |
0705.2821 | Yoshihiko Okamoto | Yoshihiko Okamoto, Minoru Nohara, Hiroko Aruga-Katori and Hidenori
Takagi | Spin-Liquid State in the S = 1/2 Hyperkagome Antiferromagnet Na4Ir3O8 | 4 pages, 4 figures | Phys. Rev. Lett. 99, 137207 (2007) | 10.1103/PhysRevLett.99.137207 | null | cond-mat.str-el | null | A spinel related oxide, Na4Ir3O8, was found to have a three dimensional
network of corner shared Ir4+ (t2g^5) triangles. This gives rise to an
antiferromagnetically coupled S = 1/2 spin system formed on a geometrically
frustrated hyperkagome lattice. Magnetization M and magnetic specific heat Cm
data showed the absence of long range magnetic ordering at least down to 2 K.
The large Cm at low temperatures is independent of applied magnetic field up to
12 T, in striking parallel to the behavior seen in triangular and kagome
antiferromagnets reported to have a spin-liquid ground state. These results
strongly suggest that the ground state of Na4Ir3O8 is a three dimensional
manifestation of a spin liquid.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 14:22:39 GMT"
},
{
"version": "v2",
"created": "Sat, 29 Sep 2007 07:53:13 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Okamoto",
"Yoshihiko",
""
],
[
"Nohara",
"Minoru",
""
],
[
"Aruga-Katori",
"Hiroko",
""
],
[
"Takagi",
"Hidenori",
""
]
] |
0705.2822 | Rikard Bogvad | Julius Borcea, Rikard B{\o}gvad, Boris Shapiro | Homogenized spectral problems for exactly solvable operators:
asymptotics of polynomial eigenfunctions | A non-trivial mistake in the proof of Proposition 6 has been
corrected. This does not necessitate any changes in the statement of
Proposition 6 or in other results in the paper | null | null | null | math.CA math.CV math.SP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Consider a homogenized spectral pencil of exactly solvable linear
differential operators $T_{\la}=\sum_{i=0}^k Q_{i}(z)\la^{k-i}\frac
{d^i}{dz^i}$, where each $Q_{i}(z)$ is a polynomial of degree at most $i$ and
$\la$ is the spectral parameter. We show that under mild nondegeneracy
assumptions for all sufficiently large positive integers $n$ there exist
exactly $k$ distinct values $\la_{n,j}$, $1\le j\le k$, of the spectral
parameter $\la$ such that the operator $T_{\la}$ has a polynomial eigenfunction
$p_{n,j}(z)$ of degree $n$. These eigenfunctions split into $k$ different
families according to the asymptotic behavior of their eigenvalues. We
conjecture and prove sequential versions of three fundamental properties: the
limits $\Psi_{j}(z)=\lim_{n\to\infty} \frac{p_{n,j}'(z)}{\la_{n,j}p_{n,j}(z)}$
exist, are analytic and satisfy the algebraic equation $\sum_{i=0}^k Q_{i}(z)
\Psi_{j}^i(z)=0$ almost everywhere in $\bCP$. As a consequence we obtain a
class of algebraic functions possessing a branch near $\infty\in \bCP$ which is
representable as the Cauchy transform of a compactly supported probability
measure.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 15:45:55 GMT"
},
{
"version": "v2",
"created": "Fri, 19 Sep 2008 10:51:58 GMT"
},
{
"version": "v3",
"created": "Mon, 20 Sep 2010 16:42:27 GMT"
}
] | 2010-09-21T00:00:00 | [
[
"Borcea",
"Julius",
""
],
[
"Bøgvad",
"Rikard",
""
],
[
"Shapiro",
"Boris",
""
]
] |
0705.2823 | Mario Salvetti | Filippo Callegaro, Davide Moroni, Mario Salvetti | Cohomology of affine Artin groups and applications | 21 pages, 4 figures | null | null | null | math.AT | null | The result of this paper is the determination of the cohomology of Artin
groups of type A_n, B_n and \tilde{A}_{n} with non-trivial local coefficients.
The main result is an explicit computation of the cohomology of the Artin group
of type B_n with coefficients over the module \Q[q^{\pm 1},t^{\pm 1}]. Here the
first (n-1) standard generators of the group act by (-q)-multiplication, while
the last one acts by (-t)-multiplication. The proof uses some technical results
from previous papers plus computations over a suitable spectral sequence. The
remaining cases follow from an application of Shapiro's lemma, by considering
some well-known inclusions: we obtain the rational cohomology of the Artin
group of affine type \tilde{A}_{n} as well as the cohomology of the classical
braid group {Br}_{n} with coefficients in the n-dimensional representation
presented in \cite{tong}. The topological counterpart is the explicit
construction of finite CW-complexes endowed with a free action of the Artin
groups, which are known to be K(\pi,1) spaces in some cases (including finite
type groups). Particularly simple formulas for the Euler-characteristic of
these orbit spaces are derived.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 15:46:18 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Callegaro",
"Filippo",
""
],
[
"Moroni",
"Davide",
""
],
[
"Salvetti",
"Mario",
""
]
] |
0705.2824 | Alain Pham Ngoc Dinh | Alain Pham Ngoc Dinh (MAPMO), Pham Hoang Quan (UNS-HCMC), Dang Duc
Trong (UNS-HCMC) | Sinc Approximation of the Heat Distribution on the Boundary of a
Two-Dimensional Finite Slab | 10 pages | Nonlinear Analysis Real World Applications, 9 (2008) 1103-1111 | null | null | math.AP | null | We consider the two-dimensional problem of recovering globally in time the
heat distribution on the surface of a layer inside of a heat conducting body
from two interior temperature measurements. The problem is ill-posed. The
approximation function is represented by a two-dimensional Sinc series and the
error estimate is given.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 16:29:01 GMT"
}
] | 2008-07-16T00:00:00 | [
[
"Dinh",
"Alain Pham Ngoc",
"",
"MAPMO"
],
[
"Quan",
"Pham Hoang",
"",
"UNS-HCMC"
],
[
"Trong",
"Dang Duc",
"",
"UNS-HCMC"
]
] |
0705.2825 | Alain Pham Ngoc Dinh | Tran Ngoc Lien, Dang Duc Trong (UNS-HCMC), Alain Pham Ngoc Dinh
(MAPMO) | Laguerre polynomials and the inverse Laplace transform using discrete
data | 14 pages | Journal of Mathematical Analysis and applications 337 (2008)
1302-1314 | 10.1016/j.jmaa.2007.04.066 | null | math.AP | null | We consider the problem of finding a function defined on $(0,\infty)$ from a
countable set of values of its Laplace transform. The problem is severely
ill-posed. We shall use the expansion of the function in a series of Laguerre
polynomials to convert the problem in an analytic interpolation problem. Then,
using the coefficients of Lagrange polynomials we shall construct a stable
approximation solution.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 16:29:54 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Lien",
"Tran Ngoc",
"",
"UNS-HCMC"
],
[
"Trong",
"Dang Duc",
"",
"UNS-HCMC"
],
[
"Dinh",
"Alain Pham Ngoc",
"",
"MAPMO"
]
] |
0705.2826 | Iv\'an S\'anchez | I. S\'anchez, J.R. Darias, R. Paredes, C.J. Lobb, G. Guti\'errez | Granular instability in a vibrated U tube | 4 pages, 5 figures, submitted | null | null | null | cond-mat.soft | null | We study experimentally the collective motion of grains inside a U shaped
tube undergoing vertical oscillations, and we develop a very simple
quantitative model that captures relevant features of the observed behaviour.
The height difference between the granular columns grows with time when the
system is shaken at sufficiently low frequencies. The system exhibits two types
of growth: exponentially divergent (type I) and exponentially saturating (type
II), depending on the size of the grains. The type I growth can be quenched by
removing the air whereas the type II behavior can occur in the absence of air.
There is a good agreement between the model proposed and our experimental
results.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 16:33:31 GMT"
}
] | 2016-08-14T00:00:00 | [
[
"Sánchez",
"I.",
""
],
[
"Darias",
"J. R.",
""
],
[
"Paredes",
"R.",
""
],
[
"Lobb",
"C. J.",
""
],
[
"Gutiérrez",
"G.",
""
]
] |
0705.2827 | Wissam Al-Saidi | W. A. Al-Saidi, Shiwei Zhang and Henry Krakauer | Bond breaking with auxiliary-field quantum Monte Carlo | 8 pages, 3 figures and 3 tables. Submitted to JCP | JCP, 127, 144101 (2007). | 10.1063/1.2770707 | null | physics.comp-ph cond-mat.str-el physics.chem-ph | null | Bond stretching mimics different levels of electron correlation and provides
a challenging testbed for approximate many-body computational methods. Using
the recently developed phaseless auxiliary-field quantum Monte Carlo (AF QMC)
method, we examine bond stretching in the well-studied molecules BH and N$_2$,
and in the H$_{50}$ chain. To control the sign/phase problem, the phaseless AF
QMC method constrains the paths in the auxiliary-field path integrals with an
approximate phase condition that depends on a trial wave function. With single
Slater determinants from unrestricted Hartree-Fock (UHF) as trial wave
function, the phaseless AF QMC method generally gives better overall accuracy
and a more uniform behavior than the coupled cluster CCSD(T) method in mapping
the potential-energy curve. In both BH and N$_2$, we also study the use of
multiple-determinant trial wave functions from multi-configuration
self-consistent-field (MCSCF) calculations. The increase in computational cost
versus the gain in statistical and systematic accuracy are examined. With such
trial wave functions, excellent results are obtained across the entire region
between equilibrium and the dissociation limit.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 16:56:07 GMT"
}
] | 2007-10-10T00:00:00 | [
[
"Al-Saidi",
"W. A.",
""
],
[
"Zhang",
"Shiwei",
""
],
[
"Krakauer",
"Henry",
""
]
] |
0705.2828 | Will Kazez | Ko Honda, William H. Kazez, Gordana Matic | The contact invariant in sutured Floer homology | 29 pages, 24 figures | null | null | null | math.GT | null | We describe an invariant of a contact 3-manifold with convex boundary as an
element of Juh\'asz's sutured Floer homology. Our invariant generalizes the
contact invariant in Heegaard Floer homology in the closed case, due to
Ozsv\'ath and Szab\'o.
This version has some clarifications and new figures.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 00:02:36 GMT"
},
{
"version": "v2",
"created": "Sun, 21 Oct 2007 23:22:02 GMT"
}
] | 2007-10-22T00:00:00 | [
[
"Honda",
"Ko",
""
],
[
"Kazez",
"William H.",
""
],
[
"Matic",
"Gordana",
""
]
] |
0705.2829 | Samuel Grushevsky | Samuel Grushevsky, Igor Krichever | Integrable discrete Schrodinger equations and a characterization of Prym
varieties by a pair of quadrisecants | null | Duke Math. J. 152, no. 2 (2010), 317-371 | 10.1215/00127094-2010-014 | null | math.AG hep-th | null | We prove that Prym varieties are characterized geometrically by the existence
of a symmetric pair of quadrisecant planes of the associated Kummer variety. We
also show that Prym varieties are characterized by certain (new)
theta-functional equations. For this purpose we construct and study a
difference-differential analog of the Novikov-Veselov hierarchy.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 17:22:34 GMT"
}
] | 2019-12-19T00:00:00 | [
[
"Grushevsky",
"Samuel",
""
],
[
"Krichever",
"Igor",
""
]
] |
0705.2830 | Filippo Callegaro | Filippo Callegaro, Davide Moroni, Mario Salvetti | The K(\pi, 1) problem for the affine Artin group of type \widetilde{B}_n
and its cohomology | 21 pages | J. Eur. Math. Soc. (JEMS) 12 (2010), no. 1, 1-22 | 10.4171/JEMS/187 | null | math.AT | null | In this paper we prove that the complement to the affine complex arrangement
of type \widetilde{B}_n is a K(\pi, 1) space. We also compute the cohomology of
the affine Artin group G of type \widetilde{B}_n with coefficients over several
interesting local systems. In particular, we consider the module Q[q^{\pm 1},
t^{\pm 1}], where the first n-standard generators of G act by
(-q)-multiplication while the last generator acts by (-t)-multiplication. Such
representation generalizes the analog 1-parameter representation related to the
bundle structure over the complement to the discriminant hypersurface, endowed
with the monodromy action of the associated Milnor fibre. The cohomology of G
with trivial coefficients is derived from the previous one.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 17:26:33 GMT"
}
] | 2012-10-02T00:00:00 | [
[
"Callegaro",
"Filippo",
""
],
[
"Moroni",
"Davide",
""
],
[
"Salvetti",
"Mario",
""
]
] |
0705.2831 | Emanuele Daddi | E. Daddi, M. Dickinson, G. Morrison, R. Chary, A. Cimatti, D. Elbaz,
D. Frayer, A. Renzini, A. Pope, D.M. Alexander, F.E. Bauer, M. Giavalisco, M.
Huynh, J. Kurk, M. Mignoli | Multiwavelength study of massive galaxies at z~2. I. Star formation and
galaxy growth | 19 pages, 18 figures. ApJ in press. A figure added. See also the
companion paper arXiv:0705.2832 | Astrophys.J.670:156-172,2007 | 10.1086/521818 | null | astro-ph | null | Examining a sample of massive galaxies at 1.4<z<2.5 with K_{Vega}<22 from the
Great Observatories Origins Deep Survey, we compare photometry from Spitzer at
mid- and far-IR, to submillimeter, radio and rest-frame ultraviolet
wavelengths, to test the agreement between different tracers of star formation
rates (SFRs) and to explore the implications for galaxy assembly. For z~2
galaxies with moderate luminosities(L_{8um}<10^{11}L_sun), we find that the SFR
can be estimated consistently from the multiwavelength data based on local
luminosity correlations. However,20--30% of massive galaxies, and nearly all
those with L_{8um}>10^{11}L_sun, show a mid-IR excess which is likely due to
the presence of obscured active nuclei, as shown in a companion paper. There is
a tight and roughly linear correlation between stellar mass and SFR for
24um-detected galaxies. For a given mass, the SFR at z=2 was larger by a factor
of ~4 and ~30 relative to that in star forming galaxies at z=1 and z=0,
respectively. Typical ultraluminous infrared galaxies (ULIRGs) at z=2 are
relatively 'transparent' to ultraviolet light, and their activity is long lived
(~400 Myr), unlike that in local ULIRGs and high redshift
submillimeter-selected galaxies. ULIRGs are the common mode of star formation
in massive galaxies at z=2, and the high duty cycle suggests that major mergers
are not the dominant trigger for this activity.Current galaxy formation models
underpredict the normalization of the mass-SFR correlation by about a factor of
4, and the space density of ULIRGs by an orderof magnitude, but give better
agreement for z>1.4 quiescent galaxies.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 17:48:55 GMT"
},
{
"version": "v2",
"created": "Tue, 24 Jul 2007 04:29:25 GMT"
}
] | 2010-04-06T00:00:00 | [
[
"Daddi",
"E.",
""
],
[
"Dickinson",
"M.",
""
],
[
"Morrison",
"G.",
""
],
[
"Chary",
"R.",
""
],
[
"Cimatti",
"A.",
""
],
[
"Elbaz",
"D.",
""
],
[
"Frayer",
"D.",
""
],
[
"Renzini",
"A.",
""
],
[
"Pope",
"A.",
""
],
[
"Alexander",
"D. M.",
""
],
[
"Bauer",
"F. E.",
""
],
[
"Giavalisco",
"M.",
""
],
[
"Huynh",
"M.",
""
],
[
"Kurk",
"J.",
""
],
[
"Mignoli",
"M.",
""
]
] |
0705.2832 | Emanuele Daddi | E. Daddi, D.M. Alexander, M. Dickinson, R. Gilli, A. Renzini, D.
Elbaz, A. Cimatti, R. Chary, D. Frayer, F.E. Bauer, W.N. Brandt, M.
Giavalisco, N.A. Grogin, M. Huynh, J. Kurk, M. Mignoli, G. Morrison, A. Pope,
S. Ravindranath | Multiwavelength study of massive galaxies at z~2. II. Widespread Compton
thick AGN and the concurrent growth of black holes and bulges | 18 pages, 10 figures. ApJ in press. Minor changes only. See also the
companion paper arXiv:0705.2831 | null | 10.1086/521820 | null | astro-ph | null | Approximately 20-30% of 1.4<z<2.5 galaxies with K<22 (Vega) detected with
Spitzer MIPS at 24um show excess mid-IR emission relative to that expected
based on the rates of star formation measured from other multiwavelength
data.These galaxies also display some near-IR excess in Spitzer IRAC data, with
a spectral energy distribution peaking longward of 1.6um in the rest frame,
indicating the presence of warm-dust emission usually absent in star forming
galaxies. Stacking Chandra data for the mid-IR excess galaxies yields a
significant hard X-ray detection at rest-frame energies >6.2 keV. The stacked
X-ray spectrum rises steeply at >10 keV, suggesting that these sources host
Compton-thick Active Galactic Nuclei (AGNs) with column densities N_H~10^{24}
cm^-2 and an average, unobscured X-ray luminosity L_{2-8 keV}~(1-4)x10^43
erg/s. Their sky density(~3200 deg^-2) and space density (~2.6x10^-4 Mpc^-3)
are twice those of X-ray detected AGNs at z~2, and much larger than those of
previously-known Compton thick sources at similar redshifts. The mid-IR excess
galaxies are part of the long sought-after population of distant heavily
obscured AGNs predicted by synthesis models of the X-ray background. The
fraction of mid-IR excess objects increases with galaxy mass, reaching ~50-60%
for M~10^11 M_sun, an effect likely connected with downsizing in galaxy
formation. The ratio of theinferred black hole growth rate from these
Compton-thick sources to the global star formation rate at z=2 is similar to
the mass ratio of black holes to stars inlocal spheroids, implying concurrent
growth of both within the precursors oftoday's massive galaxies.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 17:49:50 GMT"
},
{
"version": "v2",
"created": "Tue, 24 Jul 2007 04:43:39 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Daddi",
"E.",
""
],
[
"Alexander",
"D. M.",
""
],
[
"Dickinson",
"M.",
""
],
[
"Gilli",
"R.",
""
],
[
"Renzini",
"A.",
""
],
[
"Elbaz",
"D.",
""
],
[
"Cimatti",
"A.",
""
],
[
"Chary",
"R.",
""
],
[
"Frayer",
"D.",
""
],
[
"Bauer",
"F. E.",
""
],
[
"Brandt",
"W. N.",
""
],
[
"Giavalisco",
"M.",
""
],
[
"Grogin",
"N. A.",
""
],
[
"Huynh",
"M.",
""
],
[
"Kurk",
"J.",
""
],
[
"Mignoli",
"M.",
""
],
[
"Morrison",
"G.",
""
],
[
"Pope",
"A.",
""
],
[
"Ravindranath",
"S.",
""
]
] |
0705.2833 | Nikolai Ustinov | N.V. Ustinov | Optical Solitons in an Anisotropic Medium with Arbitrary Dipole Moments | 5 pages, International Conference on Coherent and Nonlinear Optics
(ICONO 2007) | Proceedings of SPIE, 2007, Vol. 6725 "ICONO 2007: Nonlinear
Space-Time Dynamics" (edited by Kivshar Yu., Rosanov N.), pp. 67250F-1 -
67250F-5 | 10.1117/12.751404 | null | nlin.SI nlin.PS | null | We find the Lax pair for a system of reduced Maxwell-Bloch equations that
describes the propagation of two-component extremely short electromagnetic
pulses through the medium containing two-level quantum particles with arbitrary
dipole moments.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 18:12:44 GMT"
}
] | 2008-03-12T00:00:00 | [
[
"Ustinov",
"N. V.",
""
]
] |
0705.2834 | Itzhak Bars | Itzhak Bars, Shih-Hung Chen, Guillaume Quelin | Dual Field Theories In (d-1)+1 Emergent Spacetimes From A Unifying Field
Theory In d+2 Spacetime | LaTeX, 35 pages | Phys.Rev.D76:065016,2007 | 10.1103/PhysRevD.76.065016 | USC-07/HEP-B4 | hep-th | null | According to Two-Time Physics, there is more to space-time than can be
garnered with the ordinary formulation of physics. Two-Time Physics has shown
that the Standard Model of Particles and Forces is successfully reproduced by a
two-time field theory in 4 space and 2 time dimensions projected as a
holographic image on an emergent spacetime in 3+1 dimensions. Among the
successes of this approach is the resolution of the strong CP problem of QCD as
an outcome of the restrictions imposed by the higher symmetry structures in 4+2
dimensions. In this paper we launch a program to construct the duals of the
Standard Model as other holographic images of the same 4+2 dimensional theory
on a variety of emergent spacetimes in 3+1 dimensions. These dual field
theories are obtained as a family of gauge choices in the master 4+2 field
theory. In the present paper we deal with some of the simpler gauge choices
which lead to interacting Klein-Gordon field theories for the conformal scalar
with a predicted SO(d,2) symmetry in a variety of interesting curved spacetimes
in (d-1)+1 dimensions. More challenging and more interesting gauge choices
(including some that relate to mass) which are left to future work are also
outlined. Through this approach we discover a new realm of previously
unexplored dualities and hidden symmetries that exist both in the macroscopic
and microscopic worlds, at the classical and quantum levels. Such phenomena
predicted by 2T-physics can in principle be confirmed both by theory and
experiment. 1T-physics can be used to analyze the predictions but in most
instances gives no clue that the predicted phenomena exist in the first place.
This point of view suggests a new paradigm for the construction of a
fundamental theory that is likely to impact on the quest for unification.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 19:19:36 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bars",
"Itzhak",
""
],
[
"Chen",
"Shih-Hung",
""
],
[
"Quelin",
"Guillaume",
""
]
] |
0705.2835 | Binhai Zhu | Sergey Bereg, Marina Gavrilova and Binhai Zhu | Voronoi Diagram of Polygonal Chains under the Discrete Fr\'echet
Distance | 13 pages, 2 figures | null | null | null | cs.CG cs.CC | null | Polygonal chains are fundamental objects in many applications like pattern
recognition and protein structure alignment. A well-known measure to
characterize the similarity of two polygonal chains is the famous Fr\`{e}chet
distance. In this paper, for the first time, we consider the Voronoi diagram of
polygonal chains in $d$-dimension ($d=2,3$) under the discrete Fr\`{e}chet
distance. Given $n$ polygonal chains ${\cal C}$ in $d$-dimension ($d=2,3$),
each with at most $k$ vertices, we prove fundamental properties of such a
Voronoi diagram {\em VD}$_F({\cal C})$ by presenting the first known upper and
lower bounds for {\em VD}$_F({\cal C})$.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 18:35:18 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bereg",
"Sergey",
""
],
[
"Gavrilova",
"Marina",
""
],
[
"Zhu",
"Binhai",
""
]
] |
0705.2836 | Adam Showman | Adam P. Showman and Curtis S. Cooper | Atmospheric dynamics of Pegasi planets | 9 pages, 6 figures, article in the proceedings of the conference
"Tenth Anniversary of 51 Peg-b : Status of and prospects for hot Jupiter
studies" | Tenth Anniversary of 51 Peg-b: Status of and prospects for hot
Jupiter studies. (2006) Eds. L. Arnold, F. Bouchy, and C. Moutou. Paris:
Frontier Group, pp. 242-250 | null | null | astro-ph | null | We present three-dimensional numerical simulations of the atmospheric
dynamics of close-orbiting planets such as HD209458b. Our simulations show that
winds of several km/sec and day-night temperature differences reaching 500-1000
K are possible at and above the photosphere. The circulation takes the form of
a broad superrotating (eastward) equatorial jet. At 0.1-1 bar, the
superrotation blows the hottest regions of the atmosphere downwind by 60
degrees of longitude, but at lower pressures the temperature pattern tracks the
stellar illumination. We predict factors of several variation in the infrared
flux received at Earth throughout an orbital cycle; if the photosphere is deep
enough (>50-100 mbar pressure), the peak infrared emission should lead the time
of secondary eclipse by 10 hours or more. Dynamics plays a key role in shaping
the spectrum, clouds, chemistry, and long-term planetary evolution.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 19:35:31 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Showman",
"Adam P.",
""
],
[
"Cooper",
"Curtis S.",
""
]
] |
0705.2837 | George Kliros S. | G. S. Kliros and P. C. Divari | Beats of the Magnetocapacitance Oscillations in Lateral Semiconductor
Superlattices | 11 pages, 7 figures, accepted by Mod. Phys. Lett. B (March 2007) | Mod. Phys. Lett. B, Vol. 21, No. 17 (2007) 1041-1050 | 10.1142/S0217984907013523 | null | cond-mat.mes-hall cond-mat.mtrl-sci | null | We present calculations on the magnetocapacitance of the two-dimensional
electron gas in a lateral semiconductor superlattice under two-dimensional weak
periodic potential modulation in the presence of a perpendicular magnetic
field. Adopting a Gaussian broadening of magnetic-field-dependent width in the
density of states, we present explicit and simple expressions for the
magnetocapacitance, valid for the relevant weak magnetic fields and modulation
strengths. As the modulation strength in both directions increase, beats of the
magnetocapacitance oscillations are observed, in the low magnetic field range
(Weiss-oscillations regime), which are absent in the one-dimensional weak
modulation case.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 19:54:46 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kliros",
"G. S.",
""
],
[
"Divari",
"P. C.",
""
]
] |
0705.2838 | Alexander O. Korotkevich | V.E. Zakharov (1,2,3,4), A.O. Korotkevich (1), A. Pushkarev (1,3), D.
Resio (5) ((1) Department of Mathematics, University of Arizona, Tucson, USA,
(2) P.N. Lebedev Physical Institute, Russia, (3) Waves and Solitons LLC,
Phoenix, USA, (4) L.D. Landau Institute for Theoretical Physics, Russia, (5)
Coastal and Hydraulics Laboratory, U.S. Army Engineer Research and
Development Center, Vicksburg, USA) | Coexistence of Weak and Strong Wave Turbulence in a Swell Propagation | 5 pages, 5 figures, Submitted in Phys. Rev. Letters | V.E. Zakharov, A.O. Korotkevich, A.N. Pushkarev, and D. Resio,
Coexistence of Weak and Strong Wave Turbulence in a Swell Propagation, Phys.
Rev. Lett., vol. 99, issue 16, p. 164501 (2007) | 10.1103/PhysRevLett.99.164501 | null | physics.ao-ph physics.comp-ph physics.flu-dyn | null | By performing two parallel numerical experiments -- solving the dynamical
Hamiltonian equations and solving the Hasselmann kinetic equation -- we
examined the applicability of the theory of weak turbulence to the description
of the time evolution of an ensemble of free surface waves (a swell) on deep
water. We observed qualitative coincidence of the results.
To achieve quantitative coincidence, we augmented the kinetic equation by an
empirical dissipation term modelling the strongly nonlinear process of
white-capping. Fitting the two experiments, we determined the dissipation
function due to wave breaking and found that it depends very sharply on the
parameter of nonlinearity (the surface steepness). The onset of white-capping
can be compared to a second-order phase transition. This result corroborates
with experimental observations by Banner, Babanin, Young.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 20:05:17 GMT"
}
] | 2011-01-04T00:00:00 | [
[
"Zakharov",
"V. E.",
""
],
[
"Korotkevich",
"A. O.",
""
],
[
"Pushkarev",
"A.",
""
],
[
"Resio",
"D.",
""
]
] |
0705.2839 | Mattias Marklund | L. Stenflo, B. Eliasson, M. Marklund | Three-dimensional instability of two nonlinearly coupled electromagnetic
waves in a plasma | 11 pages, 6 figures, to appear in Journal of Plasma Physics | null | 10.1017/S0022377807006666 | null | physics.plasm-ph | null | The three-dimensional instability of two coupled electromagnetic waves in an
unmagnetized plasma is investigated theoretically and numerically. In the
regime of two-plasmon decay, where one pump wave frequency is approximately
twice the electron plasma frequency, we find that the coupled pump waves give
rise to enhanced instability with wave vectors between those of the two beams.
In the case of ion parametric decay instability, where the pump wave decays
into one Langmuir wave and one ion acoustic wave, the instability regions are
added with no distinct amplification. Our investigation can be useful in
interpreting laser-plasma as well as ionospheric heating experiments.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 20:06:06 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Stenflo",
"L.",
""
],
[
"Eliasson",
"B.",
""
],
[
"Marklund",
"M.",
""
]
] |
0705.2840 | Laurence J. November | L. J. November | Dependence of hillslope moisture content on downhill saturation | 8 pages, 7 figures, for Water Resources Research | null | null | null | physics.geo-ph | null | We derive steady equilibria for lateral downslope moisture flow in an
idealized thin closed layer as a solution to the 1D Richards' Equation. The
equilibria are determined by two free parameters: the downslope flux and a
boundary condition. Solutions exhibit a constant downslope flow speed and
moisture content for the constant equilibrium flux, which is the product of the
two. However where an isolated zone of fixed saturation degree exists
representing a boundary condition, the flow speed immediately upslope is
reduced and the moisture content correspondingly increased to preserve the
constant equilibrium flux. The capillary head jump at the saturated zone
produces a blockage that gives a high moisture content back upslope through a
pooling distance determined by the equilibrium condition that the downslope
flux is constant. In our numerical integrations, the vertically projected
pooling height is more than 10 km for a fully saturated zone in mixed silty or
clay soils, but decreases by about an order of magnitude with every 10%
decrease in the boundary-zone saturation degree. The drying of downhill
saturated zones with the increased speed of mountain moisture outflow and
corresponding decreased mountain moisture content gives a viable explanation
for the mysterious ~69% unaccounted drop seen in the spring outflow in the La
Luz / Fresnal Watershed at Alamogordo's upstream spring-box diversions in the
semiarid southeastern New Mexico USA.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 01:09:46 GMT"
},
{
"version": "v2",
"created": "Thu, 17 Jan 2008 20:36:24 GMT"
}
] | 2008-01-17T00:00:00 | [
[
"November",
"L. J.",
""
]
] |
0705.2841 | Fabricio Toscano | Fabricio Toscano, Anatole Kenfack, Andre R. R. Carvalho, Jan M. Rost
and Alfredo M. Ozorio de Almeida | Husimi-Wigner representation of chaotic eigenstates | 21 pages, 7 figures (6 color figures), submitted to Proc. R. Soc. A | null | 10.1098/rspa.2007.0263 | null | nlin.CD quant-ph | null | Just as a coherent state may be considered as a quantum point, its
restriction to a factor space of the full Hilbert space can be interpreted as a
quantum plane. The overlap of such a factor coherent state with a full pure
state is akin to a quantum section. It defines a reduced pure state in the
cofactor Hilbert space. The collection of all the Wigner functions
corresponding to a full set of parallel quantum sections defines the
Husimi-Wigner reresentation. It occupies an intermediate ground between drastic
suppression of nonclassical features, characteristic of Husimi functions, and
the daunting complexity of higher dimensional Wigner functions. After analysing
these features for simpler states, we exploit this new representation as a
probe of numerically computed eigenstates of chaotic Hamiltonians. The
individual two-dimensional Wigner functions resemble those of semiclassically
quantized states, but the regular ring pattern is broken by dislocations.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 22:49:26 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Toscano",
"Fabricio",
""
],
[
"Kenfack",
"Anatole",
""
],
[
"Carvalho",
"Andre R. R.",
""
],
[
"Rost",
"Jan M.",
""
],
[
"de Almeida",
"Alfredo M. Ozorio",
""
]
] |
0705.2842 | Osvaldo Schilling | Osvaldo F. Schilling | The design of a very high-Q superconductor electromechanical clock | developments based upon this paper results are discussed. arXiv admin
note: substantial text overlap with arXiv:cond-mat/0510767 | Brazilian Journal of Physics 37, 425(2007) | null | null | cond-mat.supr-con physics.ins-det | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss theoretically the properties of an electromechanical oscillator
whose operation is based upon the cyclic, quasi-conservative conversion between
gravitational potential, kinetic, and magnetic energies. The system consists of
a strong-pinning type-II superconductor square loop subjected to a constant
external force and to magnetic fields. The loop oscillates in the upright
position at a frequency that can be tuned in the range 10-1000 Hz, and has
induced in it a rectified electrical current. The emphasis of this paper is on
the evaluation of the major remaining source of losses in the oscillations. We
argue that such losses should be associated with the viscous vibration of
pinned flux lines in the superconductor Nb-Ti wire, provided the oscillator is
kept close to zero Kelvin, under high-vacuum, and the magnetic field is
sufficiently uniform. We discuss how other different sources of loss would
become negligible for such operational conditions, so that a very high quality
factor Q exceeding 10^(10) might in principle be reached by the oscillator. The
prospective utilization of such oscillator as a low-frequency high-Q clock is
analyzed.Since publication the ideas in this paper have been explored both by
the author and elsewhere, in applications covering Metrology, quantum systems,
and gravimetry.
| [
{
"version": "v1",
"created": "Sat, 19 May 2007 23:03:16 GMT"
},
{
"version": "v2",
"created": "Tue, 24 Jul 2018 00:22:20 GMT"
}
] | 2018-07-27T00:00:00 | [
[
"Schilling",
"Osvaldo F.",
""
]
] |
0705.2843 | Koji Nagata | Koji Nagata | Realism violates quantum mechanics | Journal of the Physical Society of Japan, (2008), (accepted for
publication) | null | null | null | quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently, [{arXiv:0810.3134}] is accepted and published. We show that local
realistic theories violate separability of $N$-qubit quantum states by a factor
of $3^N$. Thus we have a violation factor of 3 when N=1. Realistic theories
violate a proposition of a single qubit (a state with two-dimensional space)
system, the Bloch sphere machinery of quantum mechanics. Our method uses the
ratio of each of the scalar products. The maximal possible value of the scalar
product in local realistic theories grows exponentially larger than one in
$N$-qubit separable states when the number of qubits increases. We find the
violation factor $3^N$ when the measurement setup is entire range of settings
for each of the local observers.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 01:09:48 GMT"
},
{
"version": "v2",
"created": "Fri, 25 May 2007 17:40:37 GMT"
},
{
"version": "v3",
"created": "Mon, 10 Sep 2007 03:53:57 GMT"
},
{
"version": "v4",
"created": "Wed, 5 Dec 2007 09:09:40 GMT"
},
{
"version": "v5",
"created": "Tue, 21 Oct 2008 14:37:43 GMT"
},
{
"version": "v6",
"created": "Fri, 28 Nov 2008 06:31:57 GMT"
}
] | 2008-11-28T00:00:00 | [
[
"Nagata",
"Koji",
""
]
] |
0705.2844 | Ian J. Swanson | Ian Swanson | A review of integrable deformations in AdS/CFT | 16 pages; Seminar review written for the `Brief Reviews' section of
Mod. Phys. Lett. A: [http://www.worldscinet.com/mpla/mpla.shtml] | Mod.Phys.Lett.A22:915-930,2007 | 10.1142/S0217732307023614 | null | hep-th | null | Marginal beta deformations of N=4 super-Yang-Mills theory are known to
correspond to a certain class of deformations of the S^5 background subspace of
type IIB string theory in AdS_5 x S^5. An analogous set of deformations of the
AdS_5 subspace is reviewed here. String energy spectra computed in the
near-pp-wave limit of these backgrounds match predictions encoded by discrete,
asymptotic Bethe equations, suggesting that the twisted string theory is
classically integrable in this regime. These Bethe equations can be derived
algorithmically by relying on the existence of Lax representations, and on the
Riemann-Hilbert interpretation of the thermodynamic Bethe ansatz. This letter
is a review of a seminar given at the Institute for Advanced Study, based on
research completed in collaboration with McLoughlin.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 15:38:24 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Swanson",
"Ian",
""
]
] |
0705.2845 | Herbert Vinck-Posada | Herbert Vinck-Posada, Boris A. Rodriguez, Augusto Gonzalez | Micropillar resonator in a magnetic field: Zero and Finite temperature
cases | "Paper presented in PLMCN7. To appear in Superlattices and
Microstructures" | Superlattices and Microstructures 43 (2008) 500 - 506 | 10.1016/j.spmi.2007.07.023 | null | cond-mat.mes-hall | null | In this work, we present a theoretical study of a quantum dot-microcavity
system which includes a constant magnetic field in the growth direction of the
micropillar. First, we study the zero temperature case by means of a
selfconsistent procedure with a trial function composed by a coherent photon
field and a BCS function for the electron-hole pairs. The dependence of the
ground-state energy on the magnetic field and the number of polaritons is
found. We show that the magnetic field can be used as a control parameter of
the photon number, and we make explicit the scaling of the total energy with
the number of polaritons. Next, we study this problem at finite temperatures
and obtain the scaling of the critical temperature with the number of
polaritons.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 02:02:31 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Vinck-Posada",
"Herbert",
""
],
[
"Rodriguez",
"Boris A.",
""
],
[
"Gonzalez",
"Augusto",
""
]
] |
0705.2846 | Reg Cahill | Reginald T Cahill (Flinders University) | Dynamical 3-Space: Alternative Explanation of the `Dark Matter Ring' | Latex 7 pages, 5 eps colored figures | Progress in Physics, vol. 4, 13-17, 2007. | null | null | physics.gen-ph | null | NASA has claimed the discovery of a `Ring of Dark Matter' in the galaxy
cluster CL 0024+17, see Jee M.J. et al. arXiv:0705.2171, based upon
gravitational lensing data. Here we show that the lensing can be given an
alternative explanation that does not involve `dark matter'. This explanation
comes from the new dynamics of 3-space. This dynamics involves two constant G
and alpha - the fine structure constant. This dynamics has explained the bore
hole anomaly, spiral galaxy flat rotation speeds, the masses of black holes in
spherical galaxies, gravitational light bending and lensing, all without
invoking `dark matter', and also the supernova redshift data without the need
for `dark energy'.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 02:14:42 GMT"
}
] | 2007-06-27T00:00:00 | [
[
"Cahill",
"Reginald T",
"",
"Flinders University"
]
] |
0705.2847 | Gautham Hariharan | Vasanthan Raghavan, Gautham Hariharan and Akbar Sayeed | Capacity of Sparse Multipath Channels in the Ultra-Wideband Regime | submitted to IEEE Journal on Selected Topics in Signal Processing,
special issue on Fundamental Performance Limits of Ultra-Wideband Systems,
Dec. 2006, revised Apr. 2007 | null | 10.1109/JSTSP.2007.906666 | null | cs.IT math.IT | null | This paper studies the ergodic capacity of time- and frequency-selective
multipath fading channels in the ultrawideband (UWB) regime when training
signals are used for channel estimation at the receiver. Motivated by recent
measurement results on UWB channels, we propose a model for sparse multipath
channels. A key implication of sparsity is that the independent degrees of
freedom (DoF) in the channel scale sub-linearly with the signal space dimension
(product of signaling duration and bandwidth). Sparsity is captured by the
number of resolvable paths in delay and Doppler. Our analysis is based on a
training and communication scheme that employs signaling over orthogonal
short-time Fourier (STF) basis functions. STF signaling naturally relates
sparsity in delay-Doppler to coherence in time-frequency. We study the impact
of multipath sparsity on two fundamental metrics of spectral efficiency in the
wideband/low-SNR limit introduced by Verdu: first- and second-order optimality
conditions. Recent results by Zheng et. al. have underscored the large gap in
spectral efficiency between coherent and non-coherent extremes and the
importance of channel learning in bridging the gap. Building on these results,
our results lead to the following implications of multipath sparsity: 1) The
coherence requirements are shared in both time and frequency, thereby
significantly relaxing the required scaling in coherence time with SNR; 2)
Sparse multipath channels are asymptotically coherent -- for a given but large
bandwidth, the channel can be learned perfectly and the coherence requirements
for first- and second-order optimality met through sufficiently large signaling
duration; and 3) The requirement of peaky signals in attaining capacity is
eliminated or relaxed in sparse environments.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 03:06:40 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Raghavan",
"Vasanthan",
""
],
[
"Hariharan",
"Gautham",
""
],
[
"Sayeed",
"Akbar",
""
]
] |
0705.2848 | Gautham Hariharan | Gautham Hariharan and Akbar Sayeed | Non-Coherent Capacity and Reliability of Sparse Multipath Channels in
the Wideband Regime | in the proceedings of the 2nd Information Theory and Applications
(ITA) Workshop, San Diego, Jan. 2007 | null | null | null | cs.IT math.IT | null | In contrast to the prevalent assumption of rich multipath in information
theoretic analysis of wireless channels, physical channels exhibit sparse
multipath, especially at large bandwidths. We propose a model for sparse
multipath fading channels and present results on the impact of sparsity on
non-coherent capacity and reliability in the wideband regime. A key implication
of sparsity is that the statistically independent degrees of freedom in the
channel, that represent the delay-Doppler diversity afforded by multipath,
scale at a sub-linear rate with the signal space dimension (time-bandwidth
product). Our analysis is based on a training-based communication scheme that
uses short-time Fourier (STF) signaling waveforms. Sparsity in delay-Doppler
manifests itself as time-frequency coherence in the STF domain. From a capacity
perspective, sparse channels are asymptotically coherent: the gap between
coherent and non-coherent extremes vanishes in the limit of large signal space
dimension without the need for peaky signaling. From a reliability viewpoint,
there is a fundamental tradeoff between channel diversity and learnability that
can be optimized to maximize the error exponent at any rate by appropriately
choosing the signaling duration as a function of bandwidth.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 03:26:36 GMT"
}
] | 2007-07-13T00:00:00 | [
[
"Hariharan",
"Gautham",
""
],
[
"Sayeed",
"Akbar",
""
]
] |
0705.2849 | Chengbo Wang | Chengbo Wang, Daoyuan Fang | Local Existence for Nonlinear Wave Equation with Radial Data in 2+1
Dimensions | 19pages, no figures | null | null | null | math.AP | null | We get a local existence result in $H^s$ with $s>3/2$ for second order
quasilinear wave equation with radial initial data in 2+1 dimensions, based on
an improvement of Strichartz estimate in the radial case. Moreover, we get the
corresponding local well-posed result for semilinear wave equation. The
required index of regularity here is 1/4 less than the index 7/4, which is
essentially sharp in general.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 05:57:06 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Wang",
"Chengbo",
""
],
[
"Fang",
"Daoyuan",
""
]
] |
0705.2850 | Indranil Chakrabarty ic | C.G.Chakrabarti, Indranil Chakrabarty | Boltzmann Entropy : Probability and Information | Published in Romanian Journal of Physics | Romanian Journal of Physics, Volume 52, Number 5-7, (2007) | null | null | physics.gen-ph | null | We have presented first an axiomatic derivation of Boltzmann entropy on the
basis of two axioms consistent with two basic properties of thermodynamic
entropy. We have then studied the relationship between Boltzmann entropy and
information along with its physical significance.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 06:32:05 GMT"
}
] | 2007-12-22T00:00:00 | [
[
"Chakrabarti",
"C. G.",
""
],
[
"Chakrabarty",
"Indranil",
""
]
] |
0705.2851 | Yoshiaki Himemoto | Takeshi Chiba, Yoshiaki Himemoto, Masahide Yamaguchi, Jun'ichi
Yokoyama | Effective Search Templates for a Primordial Stochastic Gravitational
Wave Background | 13 pages, 4 figures, final version to be published in PRD | Phys.Rev.D76:043516,2007 | 10.1103/PhysRevD.76.043516 | null | gr-qc astro-ph hep-ph | null | We calculate the signal-to-noise ratio (SNR) of the stochastic
gravitational-wave background in an extreme case that its spectrum has a sharp
falloff with its amplitude close to the detection threshold. Such a spectral
feature is a characteristic imprint of the change in the number of relativistic
degrees of freedom on the stochastic background generated during inflation in
the early Universe. We find that, although SNR is maximal with the correct
template which is proportional to the assumed real spectrum, its sensitivity to
the shape of template is fairly weak indicating that a simple power-law
template is sufficient to detect the signature.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 12:48:37 GMT"
},
{
"version": "v2",
"created": "Tue, 21 Aug 2007 15:04:05 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Chiba",
"Takeshi",
""
],
[
"Himemoto",
"Yoshiaki",
""
],
[
"Yamaguchi",
"Masahide",
""
],
[
"Yokoyama",
"Jun'ichi",
""
]
] |
0705.2852 | Zuo-Tang Liang | Zuo-tang Liang | Global polarization of QGP in non-central heavy ion collisions at high
energies | plenary talk at the 19th International Conference on
Ultra-Relativistic Nucleus-Nucleus Collisions (QM2006), Shanghai, China,
November 14-20, 2006 | J.Phys.G34:S323-330,2007 | 10.1088/0954-3899/34/8/S18 | null | nucl-th | null | Due to the presence of a large orbital angular momentum of the parton system
produced at the early stage of non-central heavy-ion collisions, quarks and
anti-quarks are shown to be polarized in the direction opposite to the reaction
plane which is determined by the impact-parameter and the beam momentum. The
global quark polarization via elastic scattering was first calculated in an
effective static potential model, then using QCD at finite temperature with the
hard-thermal-loop re-summed gluon propagator. The measurable consequences are
discussed. Global hyperon polarization from the hadronization of polarized
quarks are predicted independent of the hadronization scenarios. It has also
been shown that the global polarization of quarks and anti-quarks leads also to
spin alignment of vector mesons. Dedicated measurements at RHIC are underway
and some of the preliminary results are obtained. In this presentation, the
basic idea and main results of global quark polarization are presented. The
direct consequences such as global hyperon polarization and spin alignment are
summarized.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 07:41:15 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Liang",
"Zuo-tang",
""
]
] |
0705.2853 | Toyokazu Sekiguchi | Masahiro Kawasaki, Toyokazu Sekiguchi | Cosmological Constraints on Isocurvature and Tensor Perturbations | 24 pages, 8 figures | Prog.Theor.Phys.120:995-1016,2008 | 10.1143/PTP.120.995 | null | astro-ph | null | We investigate cosmological constraints on primordial isocurvature and tensor
perturbations, using recent observations of the cosmic microwave background and
the large scale structure. We find that present observations are consistent
with purely adiabatic initial conditions for the structure formation under any
priors on correlations of isocurvature modes, and upper limits on the
contribution of isocurvature and tensor perturbations are presented. We also
apply the obtained constraints to some specific theoretical models, axion
isocurvature perturbation models and curvaton models, and give some
implications for theoretical models.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 07:45:39 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Kawasaki",
"Masahiro",
""
],
[
"Sekiguchi",
"Toyokazu",
""
]
] |
0705.2854 | Asaf Cohen | Asaf Cohen, Tsachy Weissman and Neri Merhav | Scanning and Sequential Decision Making for Multi-Dimensional Data -
Part II: the Noisy Case | The second part of a two-part paper. 49 pages, 6 figures. Submitted
to IEEE Trans. Inform. Theory | null | null | null | cs.IT cs.CV math.IT | null | We consider the problem of sequential decision making on random fields
corrupted by noise. In this scenario, the decision maker observes a noisy
version of the data, yet judged with respect to the clean data. In particular,
we first consider the problem of sequentially scanning and filtering noisy
random fields. In this case, the sequential filter is given the freedom to
choose the path over which it traverses the random field (e.g., noisy image or
video sequence), thus it is natural to ask what is the best achievable
performance and how sensitive this performance is to the choice of the scan. We
formally define the problem of scanning and filtering, derive a bound on the
best achievable performance and quantify the excess loss occurring when
non-optimal scanners are used, compared to optimal scanning and filtering.
We then discuss the problem of sequential scanning and prediction of noisy
random fields. This setting is a natural model for applications such as
restoration and coding of noisy images. We formally define the problem of
scanning and prediction of a noisy multidimensional array and relate the
optimal performance to the clean scandictability defined by Merhav and
Weissman. Moreover, bounds on the excess loss due to sub-optimal scans are
derived, and a universal prediction algorithm is suggested.
This paper is the second part of a two-part paper. The first paper dealt with
sequential decision making on noiseless data arrays, namely, when the decision
maker is judged with respect to the same data array it observes.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 09:14:06 GMT"
}
] | 2007-07-13T00:00:00 | [
[
"Cohen",
"Asaf",
""
],
[
"Weissman",
"Tsachy",
""
],
[
"Merhav",
"Neri",
""
]
] |
0705.2855 | Greg Landsberg | Greg Landsberg (Brown University) (for the CDF and D0 Collaborations) | Searches for non-Standard-Model Higgs Bosons at the Tevatron | Talk given at the XLIInd Rencontres de Moriond QCD and High-Energy
Hadronic Interactions, La Thuile, Italy, March 17-24, 2007. 4 pages, 4
figures | null | null | null | hep-ex | null | Search for non-Standard-Model Higgs bosons is one of the major goals of the
ongoing Fermilab Tevatron run. Large data sets accumulated by the CDF and D0
experiments break new grounds in sensitivity. We review recent Tevatron results
on searches for Higgs bosons in Minimal Supersymmetric Model in the multi b-jet
and tau-tau final states, as well as a search for fermiophobic Higgs in the
multiphoton final state.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 09:29:24 GMT"
}
] | 2019-08-14T00:00:00 | [
[
"Landsberg",
"Greg",
"",
"Brown University"
]
] |
0705.2856 | Shi-shyr Roan | Shi-shyr Roan | The Transfer Matrix of Superintegrable Chiral Potts Model as the
Q-operator of Root-of-unity XXZ Chain with Cyclic Representation of
$U_q(sl_2)$ | Latex 27 Pages; Typos and errors corrected, Improved version with
clearer explanations for better presentation. Terminology and notations
refined. References added and updated-Journal version | J.Stat.Mech.0709:P09021,2007 | 10.1088/1742-5468/2007/09/P09021 | null | cond-mat.stat-mech hep-th math-ph math.MP math.QA nlin.SI | null | We demonstrate that the transfer matrix of the inhomogeneous $N$-state chiral
Potts model with two vertical superintegrable rapidities serves as the
$Q$-operator of XXZ chain model for a cyclic representation of $U_{\sf
q}(sl_2)$ with $N$th root-of-unity ${\sf q}$ and representation-parameter for
odd $N$. The symmetry problem of XXZ chain with a general cyclic $U_{\sf
q}(sl_2)$-representation is mapped onto the problem of studying $Q$-operator of
some special one-parameter family of generalized $\tau^{(2)}$-models. In
particular, the spin-$\frac{N-1}{2}$ XXZ chain model with ${\sf q}^N=1$ and the
homogeneous $N$-state chiral Potts model at a specific superintegrable point
are unified as one physical theory. By Baxter's method developed for producing
$Q_{72}$-operator of the root-of-unity eight-vertex model, we construct the
$Q_R, Q_L$- and $Q$-operators of a superintegrable $\tau^{(2)}$-model, then
identify them with transfer matrices of the $N$-state chiral Potts model for a
positive integer $N$. We thus obtain a new method of producing the
superintegrable $N$-state chiral Potts transfer matrix from the
$\tau^{(2)}$-model by constructing its $Q$-operator.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 09:40:36 GMT"
},
{
"version": "v2",
"created": "Fri, 6 Jul 2007 02:00:19 GMT"
},
{
"version": "v3",
"created": "Thu, 27 Sep 2007 12:25:58 GMT"
}
] | 2011-02-16T00:00:00 | [
[
"Roan",
"Shi-shyr",
""
]
] |
0705.2857 | Eli Barkai | E. Barkai, I.M. Sokolov | Multi-point Distribution Function for the Continuous Time Random Walk | 7 pages | J. of Stat. Mech: Theory and Experiment P08001 (2007) | 10.1088/1742-5468/2007/08/P08001 | null | cond-mat.stat-mech | null | We derive an explicit expression for the Fourier-Laplace transform of the
two-point distribution function $p(x_1,t_1;x_2,t_2)$ of a continuous time
random walk (CTRW), thus generalizing the result of Montroll and Weiss for the
single point distribution function $p(x_1,t_1)$. The multi-point distribution
function has a structure of a convolution of the Montroll-Weiss CTRW and the
aging CTRW single point distribution functions. The correlation function
$<x(t_1) x(t_2) >$ for the biased CTRW process is found. The random walk
foundation of the multi-time-space fractional diffusion equation [Baule and
Friedrich [{\em Europhysics Letters} {\bf 77} 10002 (2007)] is investigated
using the unbiased CTRW in the continuum limit.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 09:41:09 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Barkai",
"E.",
""
],
[
"Sokolov",
"I. M.",
""
]
] |
0705.2858 | Kluson Josef | J. Kluson | Note About Integrability and Gauge Fixing for Bosonic String on
AdS(5)xS(5) | 17 pages | JHEP 0707:015,2007 | 10.1088/1126-6708/2007/07/015 | null | hep-th | null | This short note is devoted to the study of the integrability of the bosonic
string on AdS(5)xS(5) in the uniform light-cone gauge. We construct Lax
connection for gauge fixed theory and we argue that it is flat.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 10:23:21 GMT"
}
] | 2009-04-22T00:00:00 | [
[
"Kluson",
"J.",
""
]
] |
0705.2859 | V. Hinich | Vladimir Hinich and Arkady Vaintrob | Augmented Teichmuller Spaces and Orbifolds | 92 pages; rewritten introduction, improved exposition; accepted for
publication in Selecta Mathematica. A gap in the proof of Theorem 3.2.12
fixed | null | null | null | math.CV math.AG | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study complex-analytic properties of the augmented Teichmuller spaces ATS
introduced by Lipman Bers. These spaces are obtained by adding to the classical
Teichmuller space TS the points corresponding to nodal Riemann surfaces. Unlike
TS, the space ATS is not a complex manifold (it is not even locally compact).
We prove however that the quotient of ATS by any finite index subgroup of the
Teichmuller modular group has a canonical structure of a complex orbifold.
Using this structure we construct natural maps from ATS to stacks of admissible
coverings of stable Riemann surfaces. This result is important for
understanding the cup-product in stringy orbifold cohomology. We also establish
some new technical results from the general theory of orbifolds which may be of
independent interest.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 11:15:49 GMT"
},
{
"version": "v2",
"created": "Tue, 12 Feb 2008 23:12:49 GMT"
},
{
"version": "v3",
"created": "Sat, 6 Mar 2010 16:46:05 GMT"
},
{
"version": "v4",
"created": "Wed, 20 Apr 2011 09:56:26 GMT"
}
] | 2011-04-21T00:00:00 | [
[
"Hinich",
"Vladimir",
""
],
[
"Vaintrob",
"Arkady",
""
]
] |
0705.2860 | Alexey Bogomazov | A.I. Bogomazov, V.M. Lipunov | Luminosity function of binary X-ray sources calculated using the
Scenario Machine | 22 pages, 13 figures | Astronomy Reports, volume 52, no. 4, pp. 299-310 (2008) | 10.1134/S1063772908040045 | null | astro-ph | null | Using the ``Scenario Machine'' we have carried out a population synthesis of
X-ray binaries for the purpose of modelling of X-ray luminosity functions
(XLFs) in different types of galaxies: star burst, spiral, and elliptical. This
computer code allows to calculate, by using Monte Carlo simulations, the
evolution of a large ensemble of binary systems, with proper accounting for the
spin evolution of magnetized neutron stars.
We show that the XLF has no universal type. It depends on the star formation
rate in the galaxy. Also it is of importance to take into account the evolution
of binary systems and life times of X-ray stages in theoretical models of such
functions. We have calculated cumulative and differential XLFs for the galaxy
with the constant star formation rate. Also we have calculated cumulative
luminosity functions for different intervals of time after the star formation
burst in the galaxy and curves depicting the evolution of the X-ray luminosity
after the star formation burst in the galaxy.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 11:42:54 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Bogomazov",
"A. I.",
""
],
[
"Lipunov",
"V. M.",
""
]
] |
0705.2861 | Hiroyuki Tashiro | Hiroyuki Tashiro, Nabila Aghanim, and Mathieu Langer | Secondary B-mode polarization from Faraday rotation in clusters and
galaxies | Accepted for publication in MNRAS | Mon.Not.Roy.Astron.Soc.384:733-746,2008 | 10.1111/j.1365-2966.2007.12745.x | null | astro-ph | null | We revisit the polarisation induced by Faraday rotation when Cosmic Microwave
Background photons traverse magnetised plasma. We compute the secondary B-mode
angular power spectrum from Faraday rotation due to magnetic fields in galaxies
and galaxy clusters with masses ranging from $10^{11}$ to $10^{16.5} M_\odot$.
We investigate its dependence on the electron and the magnetic field profiles.
Namely, we consider both the beta-profile of electron density as well as an
electron density distribution based on the Navarro-Frenk-White dark matter
profile. We model the magnetic field structure in galaxies and clusters
motivated by recent observations. We further account for its redshift evolution
and we examine the importance of its coherence length. We find that the B-mode
polarisation from Faraday rotation depends on the normalisation parameter
$C_l\propto \sigma_8^{5-6}$. At 30 GHz for $\sigma_8=0.8$, the B-modes from
Faraday rotation range between $0.01 {\mu \rm K}^2$ and $4 \times 10^{-3} {\mu
\rm K}^2$ at $l=10^4$ in the case of a maximally coherent fields. For smaller
coherence lengths, those amplitudes are smaller and they peak at higher
multipoles.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 12:12:43 GMT"
},
{
"version": "v2",
"created": "Tue, 4 Dec 2007 11:37:51 GMT"
},
{
"version": "v3",
"created": "Wed, 16 Jan 2008 11:36:03 GMT"
}
] | 2009-04-17T00:00:00 | [
[
"Tashiro",
"Hiroyuki",
""
],
[
"Aghanim",
"Nabila",
""
],
[
"Langer",
"Mathieu",
""
]
] |
0705.2862 | Boaz Tsaban | Dima Ruinskiy, Adi Shamir, and Boaz Tsaban | Cryptanalysis of group-based key agreement protocols using subgroup
distance functions | null | Proceedings of the 10th International Conference on Practice and
Theory in Public-Key Cryptography PKC07, Lecture Notes In Computer Science
4450 (2007), 61--75 | 10.1007/978-3-540-71677-8_5 | null | cs.CR | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We introduce a new approach for cryptanalysis of key agreement protocols
based on noncommutative groups. This approach uses functions that estimate the
distance of a group element to a given subgroup. We test it against the
Shpilrain-Ushakov protocol, which is based on Thompson's group F.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 12:20:56 GMT"
},
{
"version": "v2",
"created": "Thu, 4 Nov 2010 19:31:34 GMT"
}
] | 2010-11-05T00:00:00 | [
[
"Ruinskiy",
"Dima",
""
],
[
"Shamir",
"Adi",
""
],
[
"Tsaban",
"Boaz",
""
]
] |
0705.2863 | Daniel Alpay A | Daniel Alpay and David Levanony | On the reproducing kernel Hilbert spaces associated with the fractional
and bi-fractional Brownian motions | null | null | null | null | math.PR math.CV | null | We present decompositions of various positive kernels as integrals or sums of
positive kernels. Within this framework we study the reproducing kernel Hilbert
spaces associated with the fractional and bi-fractional Brownian motions. As a
tool, we define a new function of two complex variables, which is a natural
generalization of the classical Gamma function for the setting we consider
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 12:43:48 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Alpay",
"Daniel",
""
],
[
"Levanony",
"David",
""
]
] |
0705.2864 | Fabrizio Fiore | F. Fiore, A. Grazian, P. Santini, S. Puccetti, M. Brusa, C. Feruglio,
A. Fontana, E. Giallongo, A. Comastri, C. Gruppioni, F. Pozzi, G. Zamorani,
C. Vignali | Unveiling obscured accretion in the Chandra Deep Field South | Revised version, to be published by The Astrophysical Journal | null | 10.1086/523348 | null | astro-ph | null | A large population of heavily obscured, Compton Thick AGNs is predicted by
models of galaxy formation, models of Cosmic X-ray Background and by the
``relic'' super-massive black-hole mass function measured from local bulges.
However, so far only a handful of Compton thick AGNs have been possibly
detected using even the deepest Chandra and XMM surveys. Compton-thick AGNs can
be recovered thanks to the reprocessing of the AGN UV emission in the infrared
by selecting sources with AGN luminosity's in the mid-infrared and faint
near-infrared and optical emission. To this purpose, we make use of deep HST,
VLT, Spitzer and Chandra data on the Chandra Deep Field South to constrain the
number of Compton thick AGN in this field. We show that sources with high
24$\mu$m to optical flux ratios and red colors form a distinct source
population, and that their infrared luminosity is dominated by AGN emission.
Analysis of the X-ray properties of these extreme sources shows that most of
them (80$\pm15%$) are indeed likely to be highly obscured, Compton thick AGNs.
The number of infrared selected, Compton thick AGNs with 5.8$\mu$m luminosity
higher than $10^{44.2}$ erg s$^{-1}$ turns out to be similar to that of X-ray
selected, unobscured and moderately obscured AGNs with 2-10 keV luminosity
higher than $10^{43}$ erg s$^{-1}$ in the redshift bin 1.2-2.6. This ``factor
of 2'' source population is exactly what it is needed to solve the
discrepancies between model predictions and X-ray AGN selection.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 13:17:20 GMT"
},
{
"version": "v2",
"created": "Sat, 8 Sep 2007 15:54:13 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Fiore",
"F.",
""
],
[
"Grazian",
"A.",
""
],
[
"Santini",
"P.",
""
],
[
"Puccetti",
"S.",
""
],
[
"Brusa",
"M.",
""
],
[
"Feruglio",
"C.",
""
],
[
"Fontana",
"A.",
""
],
[
"Giallongo",
"E.",
""
],
[
"Comastri",
"A.",
""
],
[
"Gruppioni",
"C.",
""
],
[
"Pozzi",
"F.",
""
],
[
"Zamorani",
"G.",
""
],
[
"Vignali",
"C.",
""
]
] |
0705.2865 | Anselm Vossen | Anselm Vossen (for the COMPASS Collaboration) | Measurement of Transverse Spin Effects at COMPASS | 4 pages, 7 figures, in proceedings for 'Rencontres de Moriond 2007,
QCD and Hadronic interactions' | null | null | null | hep-ex | null | By measuring transverse single spin asymmetries one has access to the
transversity distribution function $\Delta_T q(x)$ and the transverse momentum
dependent Sivers function $q_0^T(x,\vec{k}_T)$. New measurements from
identified hadrons and hadron pairs, produced in deep inelastic scattering of a
transversely polarized $^6LiD$ target are presented. The data were taken in
2003 and 2004 by the COMPASS collaboration using the muon beam of the CERN SPS
at 160 GeV/c, resulting in small asymmetries.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 13:51:58 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Vossen",
"Anselm",
"",
"for the COMPASS Collaboration"
]
] |
0705.2866 | Akhlesh Lakhtakia | M. V. Shuba, S. A. Maksimenko, A. Lakhtakia | Electromagnetic wave propagation in an almost circular bundle of closely
packed, metallic, carbon nanotubes | 9 pages | null | 10.1103/PhysRevB.76.155407 | null | cond-mat.mtrl-sci | null | An equivalent-multishell approach for the approximate calculation of the
characteristics of electromagnetic waves propagating in almost circular
(azimuthally symmetric), closely packed bundles of parallel, identical, and
metallic carbon nanotubes (CNTs) yields results in reasonably good agreement
with a many-body technique, for infinitely long bundles when the number of CNTs
is moderately high. The slow-wave coefficients for azimunthally symmetric
guided waves increase with the number of metallic CNTs in the bundle, tending
for thick bundles to unity, which is characteristic of macroscopic metallic
wires. The existence of an azimuthally nonsymmetric guided wave at low
frequencies in a bundle of a large number of finite-length CNTs stands in
contrast to the characteristics of guided-wave propagation in a single CNT. The
equivalent-multishell approach yields the polarizability scalar and the antenna
efficiency of a bundle of finite-length CNTs in the long-wavelength regime over
a wide frequency range spanning the terahertz and the near-infrared regimes.
Edge effects give rise to geometric resonances in such bundles.
The antenna efficiency of a CNT bundle at the first resonance can exceed that
of a single CNT by four orders of magnitude, which is promising for the design
and development of CNT-bundle antennas and composite materials containing
CNT-bundles as inclusions.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 13:39:10 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Shuba",
"M. V.",
""
],
[
"Maksimenko",
"S. A.",
""
],
[
"Lakhtakia",
"A.",
""
]
] |
0705.2867 | Du\v{s}an Repov\v{s} | Du\v{s}an Repov\v{s}, Boaz Tsaban, and Lyubomyr Zdomskyy | Continuous selections and sigma-spaces | null | Topology Appl. 156:1 (2008), 104-109 | 10.1016/j.topol.2008.03.025 | null | math.GN math.LO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Assume that X is a metrizable separable space, and each clopen-valued lower
semicontinuous multivalued map Phi from X to Q has a continuous selection. Our
main result is that in this case, X is a sigma-space. We also derive a partial
converse implication, and present a reformulation of the Scheepers Conjecture
in the language of continuous selections.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 14:17:28 GMT"
},
{
"version": "v2",
"created": "Thu, 4 Nov 2010 19:34:51 GMT"
},
{
"version": "v3",
"created": "Fri, 5 Aug 2011 03:48:00 GMT"
}
] | 2011-08-08T00:00:00 | [
[
"Repovš",
"Dušan",
""
],
[
"Tsaban",
"Boaz",
""
],
[
"Zdomskyy",
"Lyubomyr",
""
]
] |
0705.2868 | Quesne Christiane | C. Quesne | Non-Hermitian oscillator Hamiltonian and su(1,1): a way towards
generalizations | 11 pages, no figure; changes in title and in paragraphs 3 and 5;
final published version | J.Phys.A40:F745-F751,2007 | 10.1088/1751-8113/40/30/F07 | ULB/229/CQ/07/4 | math-ph hep-th math.MP quant-ph | null | The family of metric operators, constructed by Musumbu {\sl et al} (2007 {\sl
J. Phys. A: Math. Theor.} {\bf 40} F75), for a harmonic oscillator Hamiltonian
augmented by a non-Hermitian $\cal PT$-symmetric part, is re-examined in the
light of an su(1,1) approach. An alternative derivation, only relying on
properties of su(1,1) generators, is proposed. Being independent of the
realization considered for the latter, it opens the way towards the
construction of generalized non-Hermitian (not necessarily $\cal PT$-symmetric)
oscillator Hamiltonians related by similarity to Hermitian ones. Some examples
of them are reviewed.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 13:27:34 GMT"
},
{
"version": "v2",
"created": "Fri, 20 Jul 2007 11:28:23 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Quesne",
"C.",
""
]
] |
0705.2869 | Sarah Allwood-Spiers | Sarah Allwood-Spiers | Electroweak Symmetry Breaking without a Higgs Boson at the LHC | 4 pages, to appear in the proceedings of 42st Rencontres de Moriond
on QCD and Hadronic interactions, La Thuile, Aosta Valley, Italy, 17-24 Mar
2006 | null | null | null | hep-ex | null | We present two studies into strong symmetry breaking scenarios at the LHC.
The first case is a study into vector boson scattering at ATLAS. This uses the
framework of the Electroweak Chiral Lagrangian with Pade unitarisation to
generate possible signal scenarios. Signals could be observed with an
integrated luminosity of 30 fb^{-1}. Secondly a search for the technirho,
rho_{TC}, at CMS is presented, within the Technicolour ``Straw Man'' model. 5
sigma discovery is possible starting from 4 fb^{-1}.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 13:12:02 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Allwood-Spiers",
"Sarah",
""
]
] |
0705.2870 | Chinping Chen | Lin He, Chinping Chen, Fang Liang, and Lin Guo | Anisotropy and magnetization reversal with chains of submicron-sized Co
hollow spheres | 10 pages, 5 figures, submitted to PRB | Phys. Rev. B 75, 214418 (2007) | 10.1103/PhysRevB.75.214418 | null | cond-mat.mtrl-sci | null | Magnetic properties with chains of hcp Co hollow spheres have been studied.
The diameter of the spheres ranges from 500 to 800 nm, with a typical shell
thickness of about 60 nm. The shell is polycrystalline with an average
crystallite size of 20 to 35 nm. The blocking temperature determined by the
zero-field-cooling MZFC(T) measurement at H = 90 Oe is about 325 K. The
corresponding effective anisotropy is determined as, Keff = 4.6*10^4 J/m^3. In
addition, the blocking temperature and the effective anisotropy determined by
the analysis on HC(T) are 395 K and 5.7*10^4 J/m^3, respectively. The
experimentally determined anisotropy is smaller by one order of magnitude than
the magnetocrystalline anisotropy of the bulk hcp Co, which is about 3 to
5*10^5 J/m^3. A further analysis on HC(T) shows that the magnetization reversal
follows a nucleation rotational mode with an effective switching volume, V* =
2.3*10^3 nm^3. The corresponding effective diameter is calculated as 16.4 nm.
It is slightly larger than the coherence length of Co, about 15 nm. The
possible reason for the much reduced magnetic anisotropy is discussed briefly.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 15:05:29 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"He",
"Lin",
""
],
[
"Chen",
"Chinping",
""
],
[
"Liang",
"Fang",
""
],
[
"Guo",
"Lin",
""
]
] |
0705.2871 | Dmitri Yafaev | D. Yafaev | On spectral properties of translationally invariant magnetic
Schr\"odinger operators | null | null | 10.1007/s00023-007-0354-4 | null | math.SP math-ph math.MP | null | We consider a class of translationally invariant magnetic fields such that
the corresponding potential has a constant direction.
Our goal is to study basic spectral properties of the Schr\"odinger operator
${\bf H}$ with such a potential. In particular, we show that the spectrum of
${\bf H}$ is absolutely continuous and we find its location. Then we study the
long-time behaviour of solutions $\exp(-i {\bf H} t)f$ of the time dependent
Schr\"odinger equation. It turnes out that a quantum particle remains localized
in the plane orthogonal to the direction of the potential. Its propagation in
this direction is determined by group velocities. It is to a some extent
similar to a evolution of a one-dimensional free particle but "exits" to
$+\infty$ and $-\infty$ might be essentially different.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 15:10:45 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Yafaev",
"D.",
""
]
] |
0705.2872 | James Gilson | James G. Gilson | Cosmological Coincidence and Dark Mass Problems in Einstein Universe and
Friedman Dust Universe with Einstein's Lambda Quantum Cosmology Dark Energy
Schroedinger Wave Motion | 7 pages, typing errors corrected, final calculation revised,
extraneous 2 removed, small change in title, 13 page appendix added 28 Sept
2007 July 13th 2008 Added 3 more appendices on Quantum Cosmology Dark Energy
related issues. Parts will be published in Ether Space Time and Cosmology,
PIRT Publications | null | null | null | physics.gen-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, it is shown that the cosmological model that was introduced in
a sequence of three earlier papers under the title, A Dust Universe Solution to
the Dark Energy Problem can be used to analyse and solve the Cosmological
Coincidence Problem. The generic coincidence problem that appears in the
original Einstein universe model is shown to arise from a misunderstanding
about the magnitude of dark energy density and the epoch time governing the
appearance of the integer relation between dark energy and normal energy
density. The solution to the generic case then clearly points to the source of
the time coincidence integer problem in the Friedman dust universe model. It is
then possible to eliminate this coincidence by removing a degeneracy between
different measurement epoch times. In this paper's first appendix, a
fundamental time dependent relation between dark mass and dark energy is
derived with suggestions how this relation could explain cosmological voids and
the clumping of dark mass to become visible matter. In this paper's second
appendix, it is shown that that dark energy is a conserved with time substance
that is everywhere and for all time permeable to the dark mass and visible mass
of which the contracting or expanding universe is composed. The last two
appendices involve detailed studies of cosmology, quantum dark energy related
issues. There are more detailed abstracts given with all four appendices.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 15:40:52 GMT"
},
{
"version": "v2",
"created": "Sun, 27 May 2007 11:43:13 GMT"
},
{
"version": "v3",
"created": "Tue, 29 May 2007 21:18:40 GMT"
},
{
"version": "v4",
"created": "Fri, 28 Sep 2007 14:14:15 GMT"
},
{
"version": "v5",
"created": "Sun, 13 Jul 2008 10:56:08 GMT"
}
] | 2008-07-13T00:00:00 | [
[
"Gilson",
"James G.",
""
]
] |
0705.2873 | Victor Chulaevsky | Victor Tchoulaevski (LM-Reims) | A simple extension of Stollmann's lemma to correlated potentials | null | null | null | null | math-ph math.MP | null | We propose a fairly simple and natural extension of Stollmann's lemma to
correlated random variables. This extension allows (just as the original
Stollmann's lemma does) to obtain Wegner-type estimates even in some problems
of spectral analysis of random operators where the Wegner's lemma is
inapplicable (e.g. for multi-particle Hamiltonians).
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 15:48:03 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Tchoulaevski",
"Victor",
"",
"LM-Reims"
]
] |
0705.2874 | Mario Salvetti | Mario Salvetti, Simona Settepanella | Combinatorial Morse theory and minimality of hyperplane arrangements | 29 pages | Geom. Topol. 11 (2007) 1733-1766 | 10.2140/gt.2007.11.1733 | null | math.AT math.CO | null | We find an explicit combinatorial gradient vector field on the well known
complex S (Salvetti complex) which models the complement to an arrangement of
complexified hyperplanes. The argument uses a total ordering on the facets of
the stratification of R^n associated to the arrangement, which is induced by a
generic system of polar coordinates. We give a combinatorial description of the
singular facets, finding also an algebraic complex which computes local
homology. We also give a precise construction in the case of the braid
arrangement.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 12:07:51 GMT"
}
] | 2014-11-11T00:00:00 | [
[
"Salvetti",
"Mario",
""
],
[
"Settepanella",
"Simona",
""
]
] |
0705.2875 | George Kliros S. | G. S. Kliros, J. Konstantinidis, C. Thraskias | Prediction of Macrobending and Splice Losses for Photonic Crystal Fibers
based on the Effective Index Method | 8 pages, 10 figures | WSEAS TRANSACTIONS ON COMMUNICATIONS Issue 8, Vol. 5, 2006, pp.
1314-1321 | null | null | cond-mat.mtrl-sci cond-mat.soft | null | An index-guiding photonic crystal fiber (PCF) with an array of air holes
surrounding the silica core region has special characteristics compared to
conventional single-mode fibers (SMFs). Using the effective index method and
the Gaussian beam propagation theory, the macro-bending and splice losses for
PCFs are investigated. The wavelength dependence of the cladding index of the
PCF has been taken properly into account. We obtain the effective spot size for
different configurations of PCFs, which is used for computing the splice
losses. The Gaussian approximation for the fundamental modal field leads to
simple closed-form expressions for the splice losses produced by transverse,
longitudinal and angular offsets. Calculations of macro-bending losses are
based on antenna theory for bend standard fibers.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 16:52:51 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kliros",
"G. S.",
""
],
[
"Konstantinidis",
"J.",
""
],
[
"Thraskias",
"C.",
""
]
] |
0705.2876 | Phillip Bradford | Phillip G. Bradford and Daniel A. Ray | An online algorithm for generating fractal hash chains applied to
digital chains of custody | null | null | null | null | cs.CR cs.DS | null | This paper gives an online algorithm for generating Jakobsson's fractal hash
chains. Our new algorithm compliments Jakobsson's fractal hash chain algorithm
for preimage traversal since his algorithm assumes the entire hash chain is
precomputed and a particular list of Ceiling(log n) hash elements or pebbles
are saved. Our online algorithm for hash chain traversal incrementally
generates a hash chain of n hash elements without knowledge of n before it
starts. For any n, our algorithm stores only the Ceiling(log n) pebbles which
are precisely the inputs for Jakobsson's amortized hash chain preimage
traversal algorithm. This compact representation is useful to generate,
traverse, and store a number of large digital hash chains on a small and
constrained device. We also give an application using both Jakobsson's and our
new algorithm applied to digital chains of custody for validating dynamically
changing forensics data.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 17:14:38 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bradford",
"Phillip G.",
""
],
[
"Ray",
"Daniel A.",
""
]
] |
0705.2877 | Bruno Galvan | Bruno Galvan | Origin of which-way information and generalization of the Born rule | 14 pages, 5 figures; acknowledgments added | null | null | null | quant-ph | null | The possibility to recover the which-way information, for example in the two
slit experiment, is based on a natural but implicit assumption about the
position of a particle {\it before} a position measurement is performed on it.
This assumption cannot be deduced from the standard postulates of quantum
mechanics. In the present paper this assumption is made explicit and formally
postulated as a new rule, the {\it quantum typicality rule}. This rule
correlates the positions of the particles at two different times, thus defining
their trajectories. Unexpectedly, this rule is also equivalent to the Born rule
with regard to the explanation of the results of statistical experiments. For
this reason it can be considered a generalization of the Born rule. The
existence of the quantum typicality rule strongly suggests the possibility of a
new trajectory-based formulation of quantum mechanics. According to this new
formulation, a closed quantum system is represented as a {\it quantum process},
which corresponds to a canonical stochastic process in which the probability
measure is replaced by the wave function and the usual frequentist
interpretation of probability is replaced by the quantum typicality rule.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 16:41:02 GMT"
},
{
"version": "v2",
"created": "Sun, 27 May 2007 16:48:50 GMT"
}
] | 2007-06-13T00:00:00 | [
[
"Galvan",
"Bruno",
""
]
] |
0705.2878 | Benoit Perthame | Benoit Perthame (DMA), Panagiotis E. Souganidis | Asymmetric potentials and motor effect: a large deviation approach | null | null | null | null | math.AP | null | We provide a mathematical analysis of appearance of the concentrations (as
Dirac masses) of the solution to a Fokker-Planck system with asymmetric
potentials. This problem has been proposed as a model to describe motor
proteins moving along molecular filaments. The components of the system
describe the densities of the different conformations of the proteins. Our
results are based on the study of a Hamilton-Jacobi equation arising, at the
zero diffusion limit, after an exponential transformation change of the phase
function that rises a Hamilton-Jacobi equation. We consider different classes
of conformation transitions coefficients (bounded, unbounded and locally
vanishing).
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 17:43:39 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Perthame",
"Benoit",
"",
"DMA"
],
[
"Souganidis",
"Panagiotis E.",
""
]
] |
0705.2879 | Steve Zelditch | Steve Zelditch | Bernstein polynomials, Bergman kernels and toric K\"ahler varieties | Fixed some more typos and added some detail | J. Sympl. Geom. 7 (2) (2009), 51-76 | null | null | math.CV math.SG | null | It does not seem to have been observed previously that the classical
Bernstein polynomials $B_N(f)(x)$ are closely related to the Bergman-Szego
kernels $\Pi_N$ for the Fubini-Study metric on $\CP^1$: $B_N(f)(x)$ is the
Berezin symbol of the Toeplitz operator $\Pi_N f(N^{-1} D_{\theta})$. The
relation suggests a generalization of Bernstein polynomials to any toric Kahler
variety and Delzant polytope $P$. When $f$ is smooth, $B_N(f)(x)$ admits a
complete asymptotic expansion. Integrating it over $P$ gives a complete
asymptotic expansion for Dedekind-Riemann sums of smooth functions over lattice
points in $N P$ related to Euler-MacLaurin sum formulae of Guillemin-Sternberg
and others.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 17:44:01 GMT"
},
{
"version": "v2",
"created": "Thu, 24 May 2007 14:21:21 GMT"
},
{
"version": "v3",
"created": "Mon, 4 Jun 2007 14:48:28 GMT"
}
] | 2010-07-13T00:00:00 | [
[
"Zelditch",
"Steve",
""
]
] |
0705.2880 | Sam Dolan Dr | Sam R. Dolan | Instability of the massive Klein-Gordon field on the Kerr spacetime | Added references. 27 pages, 7 figures | Phys.Rev.D76:084001,2007 | 10.1103/PhysRevD.76.084001 | null | gr-qc hep-th | null | We investigate the instability of the massive scalar field in the vicinity of
a rotating black hole. The instability arises from amplification caused by the
classical superradiance effect. The instability affects bound states: solutions
to the massive Klein-Gordon equation which tend to zero at infinity. We
calculate the spectrum of bound state frequencies on the Kerr background using
a continued fraction method, adapted from studies of quasinormal modes. We
demonstrate that the instability is most significant for the $l = 1$, $m = 1$
state, for $M \mu \lesssim 0.5$. For a fast rotating hole ($a = 0.99$) we find
a maximum growth rate of $\tau^{-1} \approx 1.5 \times 10^{-7} (GM/c^3)^{-1}$,
at $M \mu \approx 0.42$. The physical implications are discussed.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 17:56:25 GMT"
},
{
"version": "v2",
"created": "Tue, 5 Jun 2007 09:26:12 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Dolan",
"Sam R.",
""
]
] |
0705.2881 | Yuri Shtemler | Yuri M. Shtemler, Ephim Golbraikh, and Michael Mond | Wind instability of a foam layer sandwiched between the atmosphere and
the ocean | 4 pages, 2 figures | null | null | null | physics.ao-ph physics.flu-dyn | null | Wind shortwave instability of a foam layer between the atmosphere and the
ocean is examined in order to reach greater understanding of the recent
findings of the decrease in momentum transfer from hurricane winds to sea
waves. The three-fluid configuration with the high contrasts in densities of
the air, foam and water provides for an effective mechanism to stabilize the
water surface.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 18:23:04 GMT"
},
{
"version": "v2",
"created": "Fri, 20 Jul 2007 17:27:24 GMT"
},
{
"version": "v3",
"created": "Fri, 12 Oct 2007 10:50:10 GMT"
}
] | 2011-11-09T00:00:00 | [
[
"Shtemler",
"Yuri M.",
""
],
[
"Golbraikh",
"Ephim",
""
],
[
"Mond",
"Michael",
""
]
] |
0705.2882 | Leonid Levitov | Dmitry A. Abanin, Patrick A. Lee, Leonid S. Levitov | Charge and Spin Transport at the Quantum Hall Edge of Graphene | 10 pages, 6 figures, invited paper | Solid State Comm. 143, 77-85 (2007) | 10.1016/j.ssc.2007.04.024 | null | cond-mat.mes-hall cond-mat.str-el | null | Landau level bending near the edge of graphene, described using 2d Dirac
equation, provides a microscopic framework for understanding the quantum Hall
Effect (QHE) in this material. We review properties of the QHE edge states in
graphene, with emphasis on the novel phenomena that arise due to Dirac
character of electronic states. A method of mapping out the dispersion of the
edge states using scanning tunneling probes is proposed. The Zeeman splitting
of Landau levels is shown to create a particularly interesting situation around
the Dirac point, where it gives rise to counter-circulating modes with opposite
spin. These chiral spin modes lead to a rich variety of spin transport
phenomena, including spin Hall effect, spin filtering and injection, and
electric detection of spin current. The estimated Zeeman spin gap, enhanced by
exchange, of a few hundred Kelvin, makes graphene an attractive system for
spintronics. Comparison to recent transport measurements near nu=0 is
presented.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 18:37:47 GMT"
},
{
"version": "v2",
"created": "Fri, 8 Jun 2007 11:48:56 GMT"
}
] | 2008-04-13T00:00:00 | [
[
"Abanin",
"Dmitry A.",
""
],
[
"Lee",
"Patrick A.",
""
],
[
"Levitov",
"Leonid S.",
""
]
] |
0705.2883 | Ratnakar Palai | R. Palai, R.S. Katiyar, H. Schmid, P. Tissot, S.J. Clark, J.
Robertson, S.A.T. Redfern and J.F. Scott | The beta Phase of Multiferroic Bismuth Ferrite and its beta-gamma
Metal-Insulator Transition | 5 Pages, 5 grphs | Physical Review B, 77, 014110 (2008) | 10.1103/PhysRevB.77.014110 | null | cond-mat.mtrl-sci cond-mat.other | null | We show that epitaxial (001) thin films of multiferroic bismuth ferrite
BiFeO3 are monoclinic at room temperature instead of tetragonal or Rhombohedral
as reported earlier . We report a orthorhombic order-disorder beta-phase
between 820C and 950C contrary to the earlier report. The transition sequence
monoclinic-orthorhombic phase in (001)BiFeO3 thin film
(rhombohedral-orthorhombic transition in single crystal) resembles that of
BaTiO3 or PbSc1/2Ta1/2O3. The transition to the cubic $\gamma$-phase causes an
abrupt collapse of the bandgap toward zero (insulator-metal transition) at the
orthorhombic-cubic beta-gamma transition around 950C. This transition is
similar to the metal-insulator transition in Ba0.6K0.4BiO3.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 18:53:55 GMT"
},
{
"version": "v2",
"created": "Wed, 11 Jul 2007 15:39:28 GMT"
},
{
"version": "v3",
"created": "Fri, 13 Jul 2007 17:29:06 GMT"
}
] | 2008-02-01T00:00:00 | [
[
"Palai",
"R.",
""
],
[
"Katiyar",
"R. S.",
""
],
[
"Schmid",
"H.",
""
],
[
"Tissot",
"P.",
""
],
[
"Clark",
"S. J.",
""
],
[
"Robertson",
"J.",
""
],
[
"Redfern",
"S. A. T.",
""
],
[
"Scott",
"J. F.",
""
]
] |
0705.2884 | Hai-Long Her | Hai-Long Her | Symplectic Energy and Lagrangian Intersection Under Legendrian
Deformations | 16 pages, to appear in the Pacific Journal of Mathematics | null | null | null | math.SG | null | Let M be a compact symplectic manifold, and L be a closed Lagrangian
submanifold which can be lifted to a Legendrian submanifold in the
contactization of M. For any Legendrian deformation of L satisfying some given
conditions, we get a new Lagrangian submanifold L'. We prove that the number of
intersection of L and L' can be estimated from below by the sum of $Z_2$-Betti
numbers of L, provided they intersect transversally.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 18:54:54 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Her",
"Hai-Long",
""
]
] |
0705.2885 | Anders G{\aa}rdestig | A. Gardestig, K. Kubodera, and F. Myhrer (Univ. of South Carolina) | Comparison of the heavy-fermion and Foldy-Wouthuysen formalisms at third
order | 16 pages, REVTeX4, no figures, v2: references added, minor
modifications, to be published in PRC | Phys.Rev.C76:014005,2007 | 10.1103/PhysRevC.76.014005 | null | nucl-th hep-ph | null | We compare two non-relativistic (NR) reduction schemes (heavy-fermion and
Foldy-Wouthuysen) that are used to derive low-energy effective-field-theory
Lagrangians. We give the explicit transformation between the two types of
fields to O(1/m^2), derived from a quite general, relativistic Lagrangian.
Beyond leading order the NR reductions always involve the smaller components of
the Dirac spinors that are to be integrated out to formulate the NR theory.
Even so, the transformation between the NR Lagrangians can be carried out
explicitly to O(1/m^2) using a field renormalization, as long as the lower
components of the Lagrangian are known. The fixed coefficient corrections to
some low-energy constants at O(1/m^2) will depend on the particular scheme
chosen, but will match after the field renormalization.
| [
{
"version": "v1",
"created": "Mon, 21 May 2007 19:25:03 GMT"
},
{
"version": "v2",
"created": "Wed, 13 Jun 2007 15:47:27 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Gardestig",
"A.",
"",
"Univ. of South Carolina"
],
[
"Kubodera",
"K.",
"",
"Univ. of South Carolina"
],
[
"Myhrer",
"F.",
"",
"Univ. of South Carolina"
]
] |
0705.2886 | Anton Gerasimov | A. Gerasimov, D. Lebedev and S. Oblezin | New Integral Representations of Whittaker Functions for Classical Lie
Groups | 100 pages | null | null | null | math.RT | null | We propose integral representations of the Whittaker functions for the
classical Lie algebras sp(2l), so(2l) and so(2l+1). These integral
representations generalize the integral representation of gl(l+1)-Whittaker
functions first introduced by Givental. One of the salient features of the
Givental representation is its recursive structure with respect to the rank of
the Lie algebra gl(l+1). The proposed generalization of the Givental
representation to the classical Lie algebras retains this property. It was
shown elsewhere that the integral recursion operator for gl(l+1)-Whittaker
function in the Givental representation coincides with a degeneration of the
Baxter Q-operator for $\hat{gl(l+1)}$-Toda chains. We construct Q-operator for
affine Lie algebras $\hat{so(2l)}$, $\hat{so(2l+1)}$ and a twisted form of
$\hat{gl(2l)}$. We demonstrate that the relation between recursion integral
operators of the generalized Givental representation and degenerate Q-operators
remains valid for all classical Lie algebras.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 19:51:06 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Gerasimov",
"A.",
""
],
[
"Lebedev",
"D.",
""
],
[
"Oblezin",
"S.",
""
]
] |
0705.2887 | Wolfgang Sch\"afer | W. Sch\"afer, A. Szczurek | Exclusive photoproduction of $J/\psi$ in proton-proton and
proton-antiproton scattering | 22 pages, 20 figures; dedicated to Kolya Nikolaev on the occasion of
his 60th birthday; 4 figures and discussion added | Phys.Rev.D76:094014,2007 | 10.1103/PhysRevD.76.094014 | null | hep-ph | null | Protons and antiprotons at collider energies are a source of high energy
Weizs\"acker--Williams photons. This may open a possibility to study exclusive
photoproduction of heavy vector mesons at energies much larger than possible at
the HERA accelerator. Here we present a detailed investigation of the exclusive
$J/\psi$ photoproduction in proton-proton (RHIC, LHC) and proton-antiproton
(Tevatron) collisions. We calculate several differential distributions in $t_1,
t_2, y, \phi$, as well as transverse momentum distributions of $J/\Psi$'s. We
discuss correlations in the azimuthal angle between outgoing protons or proton
and antiproton as well as in the ($t_1, t_2$) space. Differently from
electroproduction experiments, here both colliding beam particles can be a
source of photons, and we find large interference terms in azimuthal angle
distributions in a broad range of rapidities of the produced meson. We also
include the spin--flip parts in the electromagnetic vertices. We discuss the
effect of absorptive corrections on various distributions. Interestingly,
absorption corrections induce a charge asymmetry in rapidity distributions, and
are larger for $p p$ reactions than for the $p \bar p$ case. The reaction
considered here constitutes an important nonreduceable background in recently
proposed searches for odderon exchange.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 19:57:37 GMT"
},
{
"version": "v2",
"created": "Tue, 21 Aug 2007 10:03:24 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Schäfer",
"W.",
""
],
[
"Szczurek",
"A.",
""
]
] |
0705.2888 | Timothy Y. Chow | Robin J. Chapman, Timothy Y. Chow, Amit Khetan, David Petrie Moulton,
Robert J. Waters | Simple formulas for lattice paths avoiding certain periodic staircase
boundaries | Accepted version (JCTA); proof of Corollary 7 expanded, and 2 new
refs added | null | null | null | math.CO | null | There is a strikingly simple classical formula for the number of lattice
paths avoiding the line x = ky when k is a positive integer. We show that the
natural generalization of this simple formula continues to hold when the line x
= ky is replaced by certain periodic staircase boundaries--but only under
special conditions. The simple formula fails in general, and it remains an open
question to what extent our results can be further generalized.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 20:04:39 GMT"
},
{
"version": "v2",
"created": "Wed, 7 May 2008 15:18:08 GMT"
}
] | 2008-05-07T00:00:00 | [
[
"Chapman",
"Robin J.",
""
],
[
"Chow",
"Timothy Y.",
""
],
[
"Khetan",
"Amit",
""
],
[
"Moulton",
"David Petrie",
""
],
[
"Waters",
"Robert J.",
""
]
] |
0705.2889 | Anton Sakovich | Anton Sakovich and Sergei Sakovich | On Transformations of the Rabelo Equations | This is a contribution to the Proc. of the Seventh International
Conference ''Symmetry in Nonlinear Mathematical Physics'' (June 24-30, 2007,
Kyiv, Ukraine), published in SIGMA (Symmetry, Integrability and Geometry:
Methods and Applications) at http://www.emis.de/journals/SIGMA/ | SIGMA 3 (2007), 086, 8 pages | 10.3842/SIGMA.2007.086 | null | nlin.SI math-ph math.AP math.DG math.MP | null | We study four distinct second-order nonlinear equations of Rabelo which
describe pseudospherical surfaces. By transforming these equations to the
constant-characteristic form we relate them to some well-studied integrable
equations. Two of the Rabelo equations are found to be related to the
sine-Gordon equation. The other two are transformed into a linear equation and
the Liouville equation, and in this way their general solutions are obtained.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 20:16:45 GMT"
},
{
"version": "v2",
"created": "Mon, 3 Sep 2007 17:00:04 GMT"
}
] | 2008-04-24T00:00:00 | [
[
"Sakovich",
"Anton",
""
],
[
"Sakovich",
"Sergei",
""
]
] |
0705.2890 | Vainshtein | S. I. Vainshtien | Anisotropy and asymmetry in fully developed turbulence | 15 pages, 8 figures | null | null | null | physics.ao-ph physics.flu-dyn | null | Using experimental longitudinal and transverse velocities data for very high
Reynolds number turbulence, we study both anisotropy and asymmetry of
turbulence. These both seem to be related to small scale turbulent structures,
and to intermittency. We may assume that the large scale velocity shear gives
an impact into the small scale turbulence, resulting in non-locality, and
related anomalous events.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 20:22:10 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Vainshtien",
"S. I.",
""
]
] |
0705.2891 | Gopal Prasad | Gopal Prasad and Andrei S. Rapinchuk | Weakly commensurable arithmetic groups, lengths of closed geodesics and
isospectral locally symmetric spaces | 62 pages | Publ. Math. IHES 109(2009) | 10.1007/s10240-009-0019-6 | null | math.DG math.NT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We introduce the notion of weak commensurabilty of arithmetic subgroups and
relate it to the length equivalence and isospectrality of locally symmetric
spaces. We prove many strong consequences of weak commensurabilty and derive
from these many interesting results about isolength and isospectral locally
symmetric spaces.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 20:36:15 GMT"
},
{
"version": "v2",
"created": "Fri, 25 May 2007 17:06:53 GMT"
},
{
"version": "v3",
"created": "Thu, 23 Aug 2007 03:07:54 GMT"
},
{
"version": "v4",
"created": "Mon, 12 May 2008 21:00:18 GMT"
},
{
"version": "v5",
"created": "Sun, 14 Sep 2008 15:00:16 GMT"
},
{
"version": "v6",
"created": "Sun, 12 Oct 2008 18:20:08 GMT"
},
{
"version": "v7",
"created": "Mon, 3 Nov 2008 16:51:23 GMT"
}
] | 2009-04-07T00:00:00 | [
[
"Prasad",
"Gopal",
""
],
[
"Rapinchuk",
"Andrei S.",
""
]
] |
0705.2892 | Jin-Ho Cho | Jin-Ho Cho and Soonkeon Nam | Non-supersymmetric Attractor with the Cosmological Constant | 15pages, 2 figures, JHEP published version, added references, added
comments on the constant addition to the entropy | JHEP 0707:011,2007 | 10.1088/1126-6708/2007/07/011 | null | hep-th | null | As a test for the non-supersymmetric attractor mechanism, we consider
extremal Reissner-Nordstr\"{o}m-(anti-)de Sitter black holes. Based on the
simple observation that the near-horizon geometry of a generic extremal black
hole contains two-dimensional anti-de Sitter factor even in the presence of the
positive cosmological constant, we apply Ashoke Sen's entropy function method
to compute the entropy of these black holes. We find the results which exactly
agree with the Bekenstein-Hawking entropy. We also obtain the constant
higher-order correction to the entropy due to the Gauss-Bonnet term.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 21:45:05 GMT"
},
{
"version": "v2",
"created": "Mon, 9 Jul 2007 19:09:23 GMT"
}
] | 2010-02-03T00:00:00 | [
[
"Cho",
"Jin-Ho",
""
],
[
"Nam",
"Soonkeon",
""
]
] |
0705.2893 | Luis Raul Abramo | L. Raul Abramo and Patrick Peter | K-Bounce | Replaced with version accepted to JCAP | JCAP0709:001,2007 | 10.1088/1475-7516/2007/09/001 | null | astro-ph gr-qc hep-th | null | By demanding that a bounce is nonsingular and that perturbations are
well-behaved at all times, we narrow the scope of possible models with one
degree of freedom that can describe a bounce in the absence of spatial
curvature. We compute the general properties of the transfer matrix of
perturbations through the bounce, and show that spectral distortions of the
Bardeen potential $\Phi$ are generically produced only for the small
wavelengths, although the spectrum of long wavelength curvature perturbations
produced in a contracting phase gets propagated unaffected through such a
bounce.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 21:52:43 GMT"
},
{
"version": "v2",
"created": "Mon, 13 Aug 2007 11:04:45 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Abramo",
"L. Raul",
""
],
[
"Peter",
"Patrick",
""
]
] |
0705.2894 | Yuri Shtemler | Yuri M. Shtemler, Isaac R. Shreiber | Heat transfer in sound propagation and attenuation through gas-liquid
polyhedral foams | 14 pages, 5 figures | International Communications in Heat and Mass Transfer 33 (2006)
571-579 | null | null | physics.gen-ph | null | A cell method is developed, which takes into account the bubble geometry of
polyhedral foams, and provides for the generalized Rayleigh-Plesset equation
that contains the non-local in time term corresponding to heat relaxation. The
Rayleigh-Plesset equation together with the equations of mass and momentum
balances for an effective single-phase inviscid fluid yield a model for foam
acoustics. The present calculations reconcile observed sound velocity and
attenuation with those predicted using the assumption that thermal dissipation
is the dominant damping mechanism in a range of foam expansions and sound
excitation frequencies.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 21:55:00 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Shtemler",
"Yuri M.",
""
],
[
"Shreiber",
"Isaac R.",
""
]
] |
0705.2895 | Roberto Onofrio | Woo-Joong Kim, James Hayden Brownell, and Roberto Onofrio | Detectability of dissipative motion in quantum vacuum via superradiance | 4 pages, 2 figures | Phys.Rev.Lett.96:200402,2006 | 10.1103/PhysRevLett.96.200402 | null | quant-ph gr-qc physics.atom-ph | null | We propose an experiment for generating and detecting vacuum-induced
dissipative motion. A high frequency mechanical resonator driven in resonance
is expected to dissipate energy in quantum vacuum via photon emission. The
photons are stored in a high quality electromagnetic cavity and detected
through their interaction with ultracold alkali-metal atoms prepared in an
inverted population of hyperfine states. Superradiant amplification of the
generated photons results in a detectable radio-frequency signal temporally
distinguishable from the expected background.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 22:40:28 GMT"
}
] | 2010-11-26T00:00:00 | [
[
"Kim",
"Woo-Joong",
""
],
[
"Brownell",
"James Hayden",
""
],
[
"Onofrio",
"Roberto",
""
]
] |
0705.2896 | Song Ming Wang | Song Ming Wang | Search for Supersymmetry at the Tevatron | 4 pages, 7 figures, Rencontres de Moriond, QCD and Hadronic
interactions, March 2007 | null | null | null | hep-ex | null | This paper reviews some of the most recent results from CDF and D0
experiments on searches for supersymmetry (SUSY) at the Tevatron. We focus on
searches for chargino/neutralino, stop, sbottom, and long lived massive SUSY
particles, on data samples up to ~1 fb-1. No signal was observed, and
constraints are set on the SUSY parameter space.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 23:22:01 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Wang",
"Song Ming",
""
]
] |
0705.2897 | Paul Cadden-Zimansky | P. Cadden-Zimansky, Z. Jiang and V. Chandrasekhar | Thermopower Oscillation Symmetries in a Double-Loop Andreev
Interferrometer | 6 Pages, 5 figures, to appear in Physica E | null | 10.1016/j.physe.2007.05.023 | null | cond-mat.mes-hall | null | Andreev interferometers, normal metal wires coupled to superconducting loops,
display phase coherent changes as the magnetic flux through the superconducting
loops is altered. Properties such as the electronic and thermal conductance of
these devices have been shown to oscillate symmetrically about zero with a
period equal to one superconducting flux quantum, $\Phi_o = h/2e$. However, the
thermopower of these devices can oscillate symmetrically or antisymmetrically
depending on the geometry of the sample, a phenomenon not well understood
theoretically. Here we report on thermopower measurements of a double-loop
Andreev interferometer where two Josephson currents in the normal metal wire
may be controlled independently. The amplitude and symmetries of the observed
thermopower oscillations may help to illuminate the unexplained dependence of
oscillation symmetry on sample geometry.
| [
{
"version": "v1",
"created": "Sun, 20 May 2007 23:55:02 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Cadden-Zimansky",
"P.",
""
],
[
"Jiang",
"Z.",
""
],
[
"Chandrasekhar",
"V.",
""
]
] |
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