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0706.0114
Edward Porter
Edward K. Porter
A New Template Family For The Detection Of Gravitational Waves From Comparable Mass Black Hole Binaries
Final published version. Accepted for publication in Phys. Rev. D
Phys.Rev.D76:104002,2007
10.1103/PhysRevD.76.104002
null
gr-qc
null
In order to improve the phasing of the comparable-mass waveform as we approach the last stable orbit for a system, various re-summation methods have been used to improve the standard post-Newtonian waveforms. In this work we present a new family of templates for the detection of gravitational waves from the inspiral of two comparable-mass black hole binaries. These new adiabatic templates are based on re-expressing the derivative of the binding energy and the gravitational wave flux functions in terms of shifted Chebyshev polynomials. The Chebyshev polynomials are a useful tool in numerical methods as they display the fastest convergence of any of the orthogonal polynomials. In this case they are also particularly useful as they eliminate one of the features that plagues the post-Newtonian expansion. The Chebyshev binding energy now has information at all post-Newtonian orders, compared to the post-Newtonian templates which only have information at full integer orders. In this work, we compare both the post-Newtonian and Chebyshev templates against a fiducially exact waveform. This waveform is constructed from a hybrid method of using the test-mass results combined with the mass dependent parts of the post-Newtonian expansions for the binding energy and flux functions. Our results show that the Chebyshev templates achieve extremely high fitting factors at all PN orders and provide excellent parameter extraction. We also show that this new template family has a faster Cauchy convergence, gives a better prediction of the position of the Last Stable Orbit and in general recovers higher Signal-to-Noise ratios than the post-Newtonian templates.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:15:34 GMT" }, { "version": "v2", "created": "Tue, 4 Sep 2007 12:26:25 GMT" }, { "version": "v3", "created": "Thu, 15 Nov 2007 11:16:12 GMT" } ]
2008-11-26T00:00:00
[ [ "Porter", "Edward K.", "" ] ]
0706.0115
Ouali Taoufik
A. Errahmani, T. Ouali
Late time acceleration in 3-brane Brans-Dicke cosmology
null
Mod.Phys.Lett.A23:3095-3111,2008
10.1142/S0217732308026881
null
gr-qc
null
In order to investigate more features of the Brans-Dicke cosmology in the five-dimensional space-time, we explore the solutions of its dynamiacal systems. A behavior of the universe in its early and late time by means of the scale factor is considered. As a results, we show that it is possible to avoid the big rip singularity and to cross the phantom divide line. Furthermore, we review the dark energy component of the universe and its agreement with the observation data for this 3-brane Brans Dicke cosmology by means of the cosmological parameters.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:17:48 GMT" }, { "version": "v2", "created": "Sat, 19 Jan 2008 08:30:21 GMT" }, { "version": "v3", "created": "Tue, 11 Mar 2008 21:18:11 GMT" } ]
2008-12-25T00:00:00
[ [ "Errahmani", "A.", "" ], [ "Ouali", "T.", "" ] ]
0706.0116
Francisco Martin Cabrera
J. C. Gonzalez Davila and F. Martin Cabrera
Harmonic G-structures
27 pages, minor corrections
null
10.1017/S0305004108001709
null
math.DG
null
For closed and connected subgroups G of SO(n), we study the energy functional on the space of G-structures of a (compact) Riemannian manifold M, where G-structures are considered as sections of the quotient bundle O(M)/G. Then, we deduce the corresponding first and second variation formulae and the characterising conditions for critical points by means of tools closely related with the study of G-structures. In this direction, we show the role in the energy functional played by the intrinsic torsion of the G-structure. Moreover, we analyse the particular case G=U(n) for even-dimensional manifolds. This leads to the study of harmonic almost Hermitian manifolds and harmonic maps from M into O(M)/U(n).
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:31:07 GMT" }, { "version": "v2", "created": "Mon, 18 Jun 2007 17:21:20 GMT" }, { "version": "v3", "created": "Mon, 9 Jul 2007 07:58:25 GMT" }, { "version": "v4", "created": "Fri, 28 Sep 2007 08:12:50 GMT" } ]
2009-11-13T00:00:00
[ [ "Davila", "J. C. Gonzalez", "" ], [ "Cabrera", "F. Martin", "" ] ]
0706.0117
Toby Johnson
Toby Johnson
Reciprocal best hits are not a logically sufficient condition for orthology
null
null
null
null
q-bio.GN
null
It is common to use reciprocal best hits, also known as a boomerang criterion, for determining orthology between sequences. The best hits may be found by blast, or by other more recently developed algorithms. Previous work seems to have assumed that reciprocal best hits is a sufficient but not necessary condition for orthology. In this article, I explain why reciprocal best hits cannot logically be a sufficient condition for orthology. If reciprocal best hits is neither sufficient nor necessary for orthology, it would seem worthwhile to examine further the logical foundations of some unsupervised algorithms that are used to identify orthologs.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:19:11 GMT" } ]
2007-06-04T00:00:00
[ [ "Johnson", "Toby", "" ] ]
0706.0118
Diana Fusco
D. Fusco, B. Bassetti, P. Jona, M. Cosentino Lagomarsino
DIA-MCIS. An Importance Sampling Network Randomizer for Network Motif Discovery and Other Topological Observables in Transcription Networks
6 pages and 1 figure, included supplementary mathematical notes
null
null
null
q-bio.QM
null
Transcription networks, and other directed networks can be characterized by some topological observables such as for example subgraph occurrence (network motifs). In order to perform such kind of analysis, it is necessary to be able to generate suitable randomized network ensembles. Typically, one considers null networks with the same degree sequences of the original ones. The commonly used algorithms sometimes have long convergence times, and sampling problems. We present here an alternative, based on a variant of the importance sampling Montecarlo developed by Chen et al. [1].
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:25:53 GMT" } ]
2007-06-04T00:00:00
[ [ "Fusco", "D.", "" ], [ "Bassetti", "B.", "" ], [ "Jona", "P.", "" ], [ "Lagomarsino", "M. Cosentino", "" ] ]
0706.0119
Kurt Girstmair
Kurt Girstmair, Gerhard Kirchner
Towards a Completion of Archimedes' Treatise on Floating Bodies
17 pages, 3 figures
null
null
null
math.HO math-ph math.MP
null
In his treatise on floating bodies Archimedes determines the equilibrium positions of a floating paraboloid segment, but only in the case when the basis of the segment is either completely outside of the fluid or completely submerged. Here we give a mathematical model for the remaining case, i.e., two simple conditions which describe the equilibria in closed form. We provide tools for finding all equilibria in a reliable way and for the classification of these equilibria. This paper can be considered as a continuation of a recent article of Rorres.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:26:35 GMT" } ]
2007-06-04T00:00:00
[ [ "Girstmair", "Kurt", "" ], [ "Kirchner", "Gerhard", "" ] ]
0706.0120
Christophe Texier
Christophe Texier
On the spectrum of the Laplace operator of metric graphs attached at a vertex -- Spectral determinant approach
LaTeX, 8 pages, 7 eps figures, v2: new appendix, v3: discussions and ref added
J. Phys. A: Math. Theor. 41 (2008) 085207
10.1088/1751-8113/41/8/085207
null
math-ph cond-mat.mes-hall math.MP
null
We consider a metric graph $\mathcal{G}$ made of two graphs $\mathcal{G}_1$ and $\mathcal{G}_2$ attached at one point. We derive a formula relating the spectral determinant of the Laplace operator $S_\mathcal{G}(\gamma)=\det(\gamma-\Delta)$ in terms of the spectral determinants of the two subgraphs. The result is generalized to describe the attachment of $n$ graphs. The formulae are also valid for the spectral determinant of the Schr\"odinger operator $\det(\gamma-\Delta+V(x))$.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:28:48 GMT" }, { "version": "v2", "created": "Thu, 19 Jul 2007 08:13:18 GMT" }, { "version": "v3", "created": "Tue, 19 Feb 2008 13:13:34 GMT" } ]
2008-02-19T00:00:00
[ [ "Texier", "Christophe", "" ] ]
0706.0121
Perret Marc
Marc Perret
Number of points of Prym varieties over finite fields
7 pages
Glasgow Math. J. 48 (2006) 275-280
null
null
math.NT math.AG
null
We establish some upper and lower bounds for the number of rational points of Prym varieties over finite fields.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:36:12 GMT" } ]
2007-06-04T00:00:00
[ [ "Perret", "Marc", "" ] ]
0706.0122
Jan Ludvig Vinningland
Jan Ludvig Vinningland, Oistein Johnsen, Eirik G. Flekkoy, Renaud Toussaint and Knut Jorgen Maloy
Granular Rayleigh-Taylor Instability: Experiments and Simulations
4 pages, 11 figures
PRL 99, 048001 (2007)
10.1103/PhysRevLett.99.048001
null
cond-mat.soft
null
A granular instability driven by gravity is studied experimentally and numerically. The instability arises as grains fall in a closed Hele-Shaw cell where a layer of dense granular material is positioned above a layer of air. The initially flat front defined by the grains subsequently develops into a pattern of falling granular fingers separated by rising bubbles of air. A transient coarsening of the front is observed right from the start by a finger merging process. The coarsening is later stabilized by new fingers growing from the center of the rising bubbles. The structures are quantified by means of Fourier analysis and quantitative agreement between experiment and computation is shown. This analysis also reveals scale invariance of the flow structures under overall change of spatial scale.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:39:05 GMT" }, { "version": "v2", "created": "Thu, 4 Oct 2007 12:45:45 GMT" } ]
2007-10-04T00:00:00
[ [ "Vinningland", "Jan Ludvig", "" ], [ "Johnsen", "Oistein", "" ], [ "Flekkoy", "Eirik G.", "" ], [ "Toussaint", "Renaud", "" ], [ "Maloy", "Knut Jorgen", "" ] ]
0706.0123
Piero Madau
Piero Madau
The Astrophysics of Early Galaxy Formation
39 pages, to appear in the proceedings of the XVIII Canary Islands Winter School of Astrophysics on "The Emission Line Universe", J. Cepa and F. Sanchez eds., Cambridge University Press
null
null
null
astro-ph
null
These lectures summarize our basic understanding of the emergence of cosmic structures, the epoch of first light, the survival of early substructure in present-day galaxy halos.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 10:47:32 GMT" } ]
2007-06-04T00:00:00
[ [ "Madau", "Piero", "" ] ]
0706.0124
Renyi Ma
R. Y. Ma, F. Yuan, D. X. Wang
Influence of the Magnetic Coupling Process on the Advection Dominated Accretion Flows around Black Holes
21 pages, 7 figures. Changed after the referee's suggestions. Accepted for publication in the Astrophysical Journal
null
10.1086/522917
null
astro-ph
null
A large-scale closed magnetic field can transfer angular momentum and energy between a black hole (BH) and its surrounding accretion flow. We investigate the effects of this magnetic coupling (MC) process on the dynamics of a hot accretion flow (e.g., an advection dominated accretion flow, hereafter ADAF). The energy and angular momentum fluxes transported by the magnetic field are derived by an equivalent circuit approach. For a rapidly rotating BH, it is found that the radial velocity and the electron temperature of the accretion flow decrease, whereas the ion temperature and the surface density increase. The significance of the MC effects depends on the value of the viscous parameter \alpha. The effects are obvious for \alpha=0.3 but nearly ignorable for \alpha=0.1. For a BH with specific angular momentum, a_*=0.9, and \alpha=0.3, we find that for reasonable parameters the radiative efficiency of a hot accretion flow can be increased by about 30%.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 11:10:31 GMT" }, { "version": "v2", "created": "Thu, 30 Aug 2007 12:54:27 GMT" } ]
2009-11-13T00:00:00
[ [ "Ma", "R. Y.", "" ], [ "Yuan", "F.", "" ], [ "Wang", "D. X.", "" ] ]
0706.0125
I. V. Zozoulenko
S. Ihnatsenka and I. V. Zozoulenko
Effect of Electron Interaction on Statistics of Conductance Oscillations in Open Quantum Dots: Does the Dephasing Time Saturate?
null
Phys. Rev. Lett. 99, 166801 (2007).
10.1103/PhysRevLett.99.166801
null
cond-mat.mes-hall
null
We perform self-consistent quantum transport calculations in open quantum dots taking into account the effect of electron interaction. We demonstrative that in the regime of the ultralow temperatures $2\pi k_BT\lesssim\Delta$ ($\Delta $ being the mean level spacing), the electron interaction strongly affects the conductance oscillations and their statistics leading to a drastic deviation from the corresponding predictions for noninteracting electrons. In particular, it causes smearing of conductance oscillations, which is similar to the effect of temperature or inelastic scattering. For $2\pi k_BT\gtrsim\Delta$ the influence of electron interaction on the conductance becomes strongly diminished. Our calculations (that are free from phenomenological parameters of the theory) are in good quantitative agreement with the observed ultralow temperature statistics (Huibers \textit{et al.}, Phys. Rev. Lett. \textbf{81}, 1917 (1998)). Our findings question a conventional interpretation of the ultralow temperature saturation of the coherence time in open dots which is based on the noninteracting theories where the electron interaction is neglected and the agrement with the experiment is achieved by introducing additional phenomenological channels of dephasing.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 11:22:20 GMT" } ]
2009-11-13T00:00:00
[ [ "Ihnatsenka", "S.", "" ], [ "Zozoulenko", "I. V.", "" ] ]
0706.0126
Muhammet Ali Can
Alexander A. Klyachko, M. Ali Can, Sinem Binicio\u{g}lu, and Alexander S. Shumovsky
A simple test for hidden variables in spin-1 system
4 pages, 1 figure
Phys. Rev. Lett. 101, 020403 (2008)
10.1103/PhysRevLett.101.020403
null
quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We resolve an old problem about the existence of hidden parameters in a three-dimensional quantum system by constructing an appropriate Bell's type inequality. This reveals a nonclassical nature of most spin-$1$ states. We shortly discuss some physical implications and an underlying cause of this nonclassical behavior, as well as a perspective of its experimental verification.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 11:26:36 GMT" }, { "version": "v2", "created": "Thu, 4 Oct 2007 14:20:45 GMT" }, { "version": "v3", "created": "Sun, 13 Apr 2008 23:42:19 GMT" }, { "version": "v4", "created": "Tue, 15 Jul 2008 09:17:44 GMT" } ]
2009-11-13T00:00:00
[ [ "Klyachko", "Alexander A.", "" ], [ "Can", "M. Ali", "" ], [ "Binicioğlu", "Sinem", "" ], [ "Shumovsky", "Alexander S.", "" ] ]
0706.0127
Riccardo Giachetti
R. Giachetti, E. Sorace
States of the Dirac equation in confining potentials
4 pages
Phys.Rev.Lett.101:190401,2008
10.1103/PhysRevLett.101.190401
null
hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the Dirac equation in confining potentials with pure vector coupling, proving the existence of metastable states with longer and longer lifetimes as the non-relativistic limit is approached and eventually merging with continuity into the Schr\"odinger bound states. We believe that the existence of these states could be relevant in high energy model construction and in understanding possible resonant scattering effects in systems like Graphene. We present numerical results for the linear and the harmonic cases and we show that the the density of the states of the continuous spectrum is well described by a sum of Breit-Wigner lines. The width of the line with lowest positive energy, as expected, reproduces very well the Schwinger pair production rate for a linear potential: we thus suggest a different way of obtaining informations on the pair production in unbounded, non uniform electric fields, where very little is known.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 11:35:53 GMT" }, { "version": "v2", "created": "Wed, 9 Jul 2008 08:39:22 GMT" } ]
2008-12-18T00:00:00
[ [ "Giachetti", "R.", "" ], [ "Sorace", "E.", "" ] ]
0706.0128
Douglas Higinbotham
G. Ron, J. Glister, B. Lee, et al. (The Jefferson Lab Hall A Collaboration)
The Proton Elastic Form Factor Ratio at Low Momentum Transfer
5 pages, 2 figures
Phys.Rev.Lett.99:202002,2007
10.1103/PhysRevLett.99.202002
JLAB-PHY-09-914
nucl-ex
null
High precision measurements of the proton elastic form factor ratio have been made at four-momentum transfers, Q^2, between 0.2 and 0.5 GeV^2. The new data, while consistent with previous results, clearly show a ratio less than unity and significant differences from the central values of several recent phenomenological fits. By combining the new form-factor ratio data with an existing cross-section measurement, one finds that in this Q^2 range the deviation from unity is primarily due to GEp being smaller than the dipole parameterization.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 17:33:29 GMT" }, { "version": "v2", "created": "Thu, 22 Nov 2007 19:18:47 GMT" } ]
2010-03-23T00:00:00
[ [ "Ron", "G.", "" ], [ "Glister", "J.", "" ], [ "Lee", "B.", "" ] ]
0706.0129
Szymon {\L}{\ke}ski
Jacek Jezierski, Jerzy Kijowski, Szymon Leski
Energy-minimizing two black holes initial data
Minor corrections, 2 references added
Phys.Rev.D76:024014,2007
10.1103/PhysRevD.76.024014
null
gr-qc
null
An attempt to construct the ``ground state'' vacuum initial data for the gravitational field surrounding two black holes is presented. The ground state is defined as the gravitational initial data minimizing the ADM mass within the class of data for which the masses of the holes and their distance are fixed. To parameterize different geometric arrangements of the two holes (and, therefore, their distance) we use an appropriately chosen scale factor. A method for analyzing the variations of the ADM mass and the masses (areas) of the horizons in terms of gravitational degrees of freedom is proposed. The Misner initial data are analyzed in this context: it is shown that they do not minimize the ADM mass.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 11:52:27 GMT" }, { "version": "v2", "created": "Fri, 27 Jul 2007 14:33:22 GMT" } ]
2008-11-26T00:00:00
[ [ "Jezierski", "Jacek", "" ], [ "Kijowski", "Jerzy", "" ], [ "Leski", "Szymon", "" ] ]
0706.0130
Christian Fuchs
Christian Fuchs
Recent progress constraining the nuclear equation of state from astrophysics and heavy ion reactions
Invited talk given at NPA III, Dresden, Germany, March 2007
J.Phys.G35:014049,2008
10.1088/0954-3899/35/1/014049
null
nucl-th
null
The quest for the nuclear equation of state (EoS) at high densities and/or extreme isospin is one of the longstanding problems of nuclear physics. Ab initio calculations for the nuclear many-body problem make predictions for the density and isospin dependence of the EoS far away from the saturation point of nuclear matter. On the other hand, in recent years substantial progress has been mode to constrain the EoS both, from the astrophysical side and from accelerator based experiments. Heavy ion experiments support a soft EoS at moderate densities while recent neutron star observations require a ``stiff'' high density behavior. Both constraints are discussed and shown to be in agreement with the predictions from many-body theory.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 11:45:56 GMT" } ]
2008-11-26T00:00:00
[ [ "Fuchs", "Christian", "" ] ]
0706.0131
Joachim Spengler
The HERA-B Collaboration
Luminosity determination at HERA-B
24 pages, 5 figures
Nucl.Instrum.Meth.A582:401-412,2007
10.1016/j.nima.2007.09.011
null
physics.data-an
null
A detailed description of an original method used to measure the luminosity accumulated by the HERA-B experiment for a data sample taken during the 2002-2003 HERA running period is reported. We show that, with this method, a total luminosity measurement can be achieved with a typical precision, including overall systematic uncertainties, at a level of 5% or better. We also report evidence for the detection of delta-rays generated in the target and comment on the possible use of such delta rays to measure luminosity.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 11:52:51 GMT" } ]
2008-11-26T00:00:00
[ [ "B Collaboration", "", "" ] ]
0706.0132
Marcus Werner
M. C. Werner, A. O. Petters
Magnification relations for Kerr lensing and testing Cosmic Censorship
13 pages, version 2: references added, minor changes. To appear in Phys. Rev. D
Phys.Rev.D76:064024,2007
10.1103/PhysRevD.76.064024
null
gr-qc astro-ph
null
A Kerr black hole with mass parameter m and angular momentum parameter a acting as a gravitational lens gives rise to two images in the weak field limit. We study the corresponding magnification relations, namely the signed and absolute magnification sums and the centroid up to post-Newtonian order. We show that there are post-Newtonian corrections to the total absolute magnification and centroid proportional to a/m, which is in contrast to the spherically symmetric case where such corrections vanish. Hence we also propose a new set of lensing observables for the two images involving these corrections, which should allow measuring a/m with gravitational lensing. In fact, the resolution capabilities needed to observe this for the Galactic black hole should in principle be accessible to current and near-future instrumentation. Since a/m >1 indicates a naked singularity, a most interesting application would be a test of the Cosmic Censorship conjecture. The technique used to derive the image properties is based on the degeneracy of the Kerr lens and a suitably displaced Schwarzschild lens at post-Newtonian order. A simple physical explanation for this degeneracy is also given.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:15:06 GMT" }, { "version": "v2", "created": "Wed, 1 Aug 2007 10:23:00 GMT" } ]
2008-11-26T00:00:00
[ [ "Werner", "M. C.", "" ], [ "Petters", "A. O.", "" ] ]
0706.0133
Eric Carlen
Eric A. Carlen, Maria C. Carvalho, Raffaele Esposito, Joel L. Lebowitz, Rossana Marra
Displacement convexity and minimal fronts at phase boundaries
This version contains additional references as well as a new section in which the joint convexity is applied to the uniqueness problem in higher dimensions
null
10.1007/s00205-008-0190-9
null
math.FA math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that certain free energy functionals that are not convex with respect to the usual convex structure on their domain of definition, are strictly convex in the sense of displacement convexity under a natural change of variables. We use this to show that in certain cases, the only critical points of these functionals are minimizers. This approach based on displacement convexity permits us to treat multicomponent systems as well as single component systems. The developments produce new examples of displacement convex functionals, and, in the multi-component setting, jointly displacement convex functionals.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:04:02 GMT" }, { "version": "v2", "created": "Thu, 17 Jul 2008 11:36:14 GMT" } ]
2009-11-13T00:00:00
[ [ "Carlen", "Eric A.", "" ], [ "Carvalho", "Maria C.", "" ], [ "Esposito", "Raffaele", "" ], [ "Lebowitz", "Joel L.", "" ], [ "Marra", "Rossana", "" ] ]
0706.0134
Petrucci
P.O. Petrucci (1), G. Ponti (2,3), G. Matt (4), A.L. Longinotti (5), J. Malzac (6), M. Mouchet (7,8), C. Boisson (7), L. Maraschi (9), K. Nandra (10), P. Ferrando (8,11) ((1) LAOG, Grenoble, France, (2) Universita degli Studi di Bologna Bologna, Italy, (3) INAF-IASF Sezione di Bologna Bologna, Italy, (4) Universita degli Studi ``Roma tre'' Roma, Italy, (5) XMM-Newton Science Operations Center, ESA, Madrid, Spain, (6) CESR Toulouse, France, (7) LUTH, Observatoire de Paris, Meudon, France, (8) APC Universite Paris 7 Paris, France, (9) Osservatorio Astronomico di Brera, Milano, Italy, (10) Astrophysics Group, Imperial College London, UK, (11) Service d'Astrophysique Gif-sur-Yvette, France)
Unveiling the broad band X-ray continuum and iron line complex in Mkr 841
Accepted in A&A. 17 pages and 21 figures
null
10.1051/0004-6361:20077787
null
astro-ph
null
Mkr 841 is a bright Seyfert 1 galaxy known to harbor a strong soft excess and a variable K$\alpha$ iron line. It has been observed during 3 different periods by XMM for a total cumulated exposure time of $\sim$108 ks. We present in this paper a broad band spectral analysis of the complete EPIC-pn data sets. We were able to test two different models for the soft excess, a relativistically blurred photoionized reflection (\r model) and a relativistically smeared ionized absorption (\a model). The continuum is modeled by a simple cut-off power law and we also add a neutral reflection. These observations reveal the extreme and puzzling spectral and temporal behaviors of the soft excess and iron line. The 0.5-3 keV soft X-ray flux decreases by a factor 3 between 2001 and 2005 and the line shape appears to be a mixture of broad and narrow components. We succeed in describing this complex broad-band 0.5-10 keV spectral variability using either \r or \a to fit the soft excess. Both models give statistically equivalent results even including simultaneous BeppoSAX data up to 200 keV. Both models are consistent with the presence of remote reflection characterized by a constant narrow component in the data. However they differ in the presence of a broad line component present in \r but not needed in \a. This study also reveals the sporadic presence of relativistically redshifted narrow iron lines.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:00:22 GMT" } ]
2009-11-13T00:00:00
[ [ "Petrucci", "P. O.", "" ], [ "Ponti", "G.", "" ], [ "Matt", "G.", "" ], [ "Longinotti", "A. L.", "" ], [ "Malzac", "J.", "" ], [ "Mouchet", "M.", "" ], [ "Boisson", "C.", "" ], [ "Maraschi", "L.", "" ], [ "Nandra", "K.", "" ], [ "Ferrando", "P.", "" ] ]
0706.0135
N. Garcia
N. Garcia
Theory of New Quantum Oscillations in the Magnetoresistance of Graphene Layers
14 page, 4 figures
null
null
null
cond-mat.mes-hall
null
We present a theory presenting new quantum oscillations in the magnetoresistance that are revealed as fine structures superimposed to the Schubnikov-de-Haas oscillations. They may be observed in experiments on graphene layers as fine structures that until now seem to have been overseen or considered to be noise. These oscillations appear also in the behaviour of the resistance as a function of the gate voltage that changes the number of carriers or Fermi level. Experimental studies of these resonances should give information of the uniformity and defects of the samples and represent a new fine structure spectroscopy. Also the lateral sample size and quantum effects may explain the absence of magnetoresistance in a few grapheme layers. Experiments are proposed.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:04:39 GMT" } ]
2007-06-04T00:00:00
[ [ "Garcia", "N.", "" ] ]
0706.0136
Mireille Capitaine
Mireille Capitaine, Catherine Donati-Martin, Delphine F\'eral
The largest eigenvalues of finite rank deformation of large Wigner matrices: convergence and nonuniversality of the fluctuations
Published in at http://dx.doi.org/10.1214/08-AOP394 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Annals of Probability 2009, Vol. 37, No. 1, 1-47
10.1214/08-AOP394
IMS-AOP-AOP394
math.PR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we investigate the asymptotic spectrum of complex or real Deformed Wigner matrices $(M_N)_N$ defined by $M_N=W_N/\sqrt{N}+A_N$ where $W_N$ is an $N\times N$ Hermitian (resp., symmetric) Wigner matrix whose entries have a symmetric law satisfying a Poincar\'{e} inequality. The matrix $A_N$ is Hermitian (resp., symmetric) and deterministic with all but finitely many eigenvalues equal to zero. We first show that, as soon as the first largest or last smallest eigenvalues of $A_N$ are sufficiently far from zero, the corresponding eigenvalues of $M_N$ almost surely exit the limiting semicircle compact support as the size $N$ becomes large. The corresponding limits are universal in the sense that they only involve the variance of the entries of $W_N$. On the other hand, when $A_N$ is diagonal with a sole simple nonnull eigenvalue large enough, we prove that the fluctuations of the largest eigenvalue are not universal and vary with the particular distribution of the entries of $W_N$.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:04:53 GMT" }, { "version": "v2", "created": "Wed, 23 Feb 2011 11:43:14 GMT" } ]
2011-02-24T00:00:00
[ [ "Capitaine", "Mireille", "" ], [ "Donati-Martin", "Catherine", "" ], [ "Féral", "Delphine", "" ] ]
0706.0137
David Sauzin
David Sauzin (IMCCE)
Resurgent functions and splitting problems
70 pages
RIMS Kokyuroku 1493 (31/05/2006) 48-117
null
null
math.DS
null
The present text is an introduction to \'Ecalle's theory of resurgent functions and alien calculus, in connection with problems of exponentially small separatrix splitting. An outline of the resurgent treatment of Abel's equation for resonant dynamics in one complex variable is included. The emphasis is on examples of nonlinear difference equations, as a simple and natural way of introducing the concepts.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:06:06 GMT" } ]
2007-06-04T00:00:00
[ [ "Sauzin", "David", "", "IMCCE" ] ]
0706.0138
David Sauzin
Stefano Marmi (SNS PISA), David Sauzin (IMCCE)
A quasianalyticity property for monogenic solutions of small divisor problems
null
Bulletin Brazilian Mathematical Society 42, 1 (2011) 45-74
10.1007/s00574-011-0003-x
null
math.DS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the quasianalytic properties of various spaces of functions suitable for one-dimensional small divisor problems. These spaces are formed of functions C^1-holomorphic on certain compact sets K_j of the Riemann sphere (in the Whitney sense), as is the solution of a linear or non-linear small divisor problem when viewed as a function of the multiplier (the intersection of K_j with the unit circle is defined by a Diophantine-type condition, so as to avoid the divergence caused by roots of unity). It turns out that a kind of generalized analytic continuation through the unit circle is possible under suitable conditions on the K_j's.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:08:01 GMT" }, { "version": "v2", "created": "Wed, 9 Mar 2011 16:22:21 GMT" } ]
2011-03-10T00:00:00
[ [ "Marmi", "Stefano", "", "SNS PISA" ], [ "Sauzin", "David", "", "IMCCE" ] ]
0706.0139
Daniel Schaerer
Daniel Schaerer (Geneva Obs, OMP)
Primeval galaxies
48 pages including figures. Lecture notes to appear in "The emission line Universe", XVIII Canary Islands Winter School of Astrophysics, Ed. J. Cepa, Cambridge Univ. Press
null
null
null
astro-ph
null
1) Introduction 2) PopIII stars and galaxies: a "top-down" theoretical approach 3) Lyman-alpha physics and astrophysics 4) Distant/primeval galaxies: observations and main results
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:16:12 GMT" } ]
2007-06-04T00:00:00
[ [ "Schaerer", "Daniel", "", "Geneva Obs, OMP" ] ]
0706.0140
Peter Bokes
J. Jung, P. Bokes, and R.W. Godby
Treatment of electron viscosity in quantum conductance
Comment on ``Dynamical corrections to the DFT-LDA electron conductance in nanoscale systems'', 10.1103/PhysRevLett.94.186810; arXiv:cond-mat/0411098v2
Phys. Rev. Lett. 98, 259701 (2007)
10.1103/PhysRevLett.98.259701
null
cond-mat.mtrl-sci cond-mat.mes-hall
null
In a recent paper Sai {\it et al.} [1] identified a correction $R^{dyn}$ to the DC conductance of nanoscale junctions arising from dynamical exchange-correlation ($XC$) effects within time-dependent density functional theory. This quantity contributes to the total resistance through $R=R_{s}+R^{dyn}$ where $R_{s}$ is the resistance evaluated in the absence of dynamical $XC$ effects. In this Comment we show that the numerical estimation of $R^{dyn}$ in example systems of the type they considered should be considerably reduced, once a more appropriate form for the shear electron viscosity $\eta$ is used.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:19:14 GMT" } ]
2008-03-18T00:00:00
[ [ "Jung", "J.", "" ], [ "Bokes", "P.", "" ], [ "Godby", "R. W.", "" ] ]
0706.0141
Jason Reese
Christopher J Greenshields and Jason M Reese
The structure of hypersonic shock waves using Navier-Stokes equations modified to include mass diffusion
written for the 2nd European Conference on AeroSpace Sciences (EUCASS), Belgium, 2007
null
null
null
physics.flu-dyn
null
Howard Brenner has recently proposed modifications to the Navier-Stokes equations that relate to a diffusion of fluid volume that would be significant for flows with high density gradients. In a previous paper (Greenshields & Reese, 2007), we found these modifications gave good predictions of the viscous structure of shock waves in argon in the range Mach 1.0-12.0 (while conventional Navier-Stokes equations are known to fail above about Mach 2). However, some areas of concern with this model were a somewhat arbitrary choice of modelling coefficient, and potentially unphysical and unstable solutions. In this paper, we therefore present slightly different modifications to include molecule mass diffusion fully in the Navier-Stokes equations. These modifications are shown to be stable and produce physical solutions to the shock problem of a quality broadly similar to those from the family of extended hydrodynamic models that includes the Burnett equations. The modifications primarily add a diffusion term to the mass conservation equation, so are at least as simple to solve as the Navier-Stokes equations; there are none of the numerical implementation problems of conventional extended hydrodynamics models, particularly in respect of boundary conditions. We recommend further investigation and testing on a number of different benchmark non-equilibrium flow cases.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:30:57 GMT" } ]
2007-06-04T00:00:00
[ [ "Greenshields", "Christopher J", "" ], [ "Reese", "Jason M", "" ] ]
0706.0142
Stefano Liberati
S. Liberati
Quantum gravity phenomenology via Lorentz violations
21 pages, 1 figure. Some overlap with arXiv:astro-ph/0505267. Proceedings contribution to invited seminar talk given at the School on Particle Physics, Gravity and Cosmology, Dubrovnik, 21 Aug - 2 Sep 2006, eds. L. Bonora, S. Fajfer, R. Iengo, D. Klabucar, S. Pallua, I. Picek. Accepted for publication on PoS
PoSP2GC:018,2007
null
null
gr-qc
null
The search for a quantum theory of gravity has been one of the main aims of theoretical physics for many years by now. However the efforts in this direction have been often hampered by the lack of experimental/observational tests able to select among, or at least constrain, the numerous quantum gravity models proposed so far. This situation has changed in the last decade thanks to the realization that some QG inspired violations of Lorentz symmetry could be constrained using current experiments and observations. This study it is not only allowing us to test at higher and higher energies a fundamental symmetry of spacetime but it is also providing us with hints and perspectives about the fundamental nature of gravity.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:39:50 GMT" } ]
2008-11-26T00:00:00
[ [ "Liberati", "S.", "" ] ]
0706.0143
Halton Arp
H. Arp, D. Carosati
A concentration of quasars around the jet galaxy NGC1097
8 pages, 5 figures Criticisms in Epilogue
null
null
null
astro-ph
null
A quasar search in the region of the active galaxy NGC 1097 yielded 31 quasars in 1984. After completion of the 2dF survey in 2004 the number of catalogued quasars just within 1 degree of the galaxy increased to 142. About 38 $\pm$ 10 of these are in excess of average background values. The evidence in 1984 is confirmed here by an increasing density of quasars as one approaches NGC 1097. Quasars within 1 degree differ from the background by being significantly brighter. There also appear two elliptical rings or arcs of quasars at r $\sim$ 20'and 40'.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:43:50 GMT" } ]
2007-06-04T00:00:00
[ [ "Arp", "H.", "" ], [ "Carosati", "D.", "" ] ]
0706.0144
N. Peter Armitage
N. P. Armitage, R. Crane, G. Sambandamurthy, A. Johansson, D. Shahar, G. Gruner
Direct observation of quantum superconducting fluctuations in an insulating groundstate
Submitted to the proceedings of SCES07
null
null
null
cond-mat.supr-con cond-mat.dis-nn
null
We review our recent measurements of the complex AC conductivity of thin InO_x films studied as a function of magnetic field through the nominal 2D superconductor-insulator transition. These measurements - the first of their type to probe nonzero frequency - reveals a significant finite frequency superfluid stiffness well into the insulating regime. Unlike conventional fluctuation superconductivity in which thermal fluctuations give a superconducting response in regions of parameter space that don't exhibit long range order, these fluctuations are temperature independent as T --> 0 and are exhibited in samples where the resistance is large (greater than 10^6 Ohms/Square) and strongly diverging. We interpret this as the direct observation of quantum superconducting fluctuations around an insulating ground state. This system serves as a prototype for other insulating states of matter that derive from superconductors.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:48:57 GMT" } ]
2007-06-04T00:00:00
[ [ "Armitage", "N. P.", "" ], [ "Crane", "R.", "" ], [ "Sambandamurthy", "G.", "" ], [ "Johansson", "A.", "" ], [ "Shahar", "D.", "" ], [ "Gruner", "G.", "" ] ]
0706.0145
Naoya Furutachi
N. Furutachi, M. kimura, A. Dot\'e, Y. Kanada-En'yo, S. oryu
Cluster structures in Oxygen isotopes
9pages, 9figures
Prog.Theor.Phys.119:403-420,2008
10.1143/PTP.119.403
null
nucl-th
null
Cluster structure of 16O,18O and 20O is investigated by the antisymmettrized molecular dynamics (AMD) plus generator coordinate method (GCM). We have found the K^{\pi}=0$_2^+$ and 0$_1^-$ rotational bands of 18O that have the prominent 14C+\alpha cluster structure. Clustering systematics becomes richer in 20O. We suggest the K^{\pi}=0$_2^+$ band that is the mixture of the 12C+\alpha+4n and 14C+6He cluster structures, and the K^{\pi}=0$_1^-$ band that has the 14C+6He cluster structure. The K^{\pi}=0$_3^+$ and 0$_2^-$ bands that have the prominent 16C+\alpha cluster structure are also found.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:51:19 GMT" } ]
2008-11-26T00:00:00
[ [ "Furutachi", "N.", "" ], [ "kimura", "M.", "" ], [ "Doté", "A.", "" ], [ "Kanada-En'yo", "Y.", "" ], [ "oryu", "S.", "" ] ]
0706.0146
Christian Daveau
Christian Daveau (AGM), Abdessatar Khelifi
Recovery of small electromagnetic inhomogeneities from boundary measurements in time-dependent Maxwell's equations
null
null
null
null
math-ph math.MP
null
We consider for the time-dependent Maxwell's equations the inverse problem of identifying locations and certain properties of small electromagnetic inhomogeneities in a homogeneous background medium from dynamic measurements of the tangential component of the magnetic field on the boundary (or a part of the boundary) of a domain.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 12:51:27 GMT" } ]
2007-06-04T00:00:00
[ [ "Daveau", "Christian", "", "AGM" ], [ "Khelifi", "Abdessatar", "" ] ]
0706.0147
Etienne Brion
E. Brion, A. S. Mouritzen and K. Molmer
Conditional dynamics induced by new configurations for Rydberg dipole-dipole interactions
5 pages, 4 figures
null
10.1103/PhysRevA.76.022334
null
quant-ph
null
We suggest a novel way to use strong Rydberg dipole-dipole interactions in order to induce non-trivial conditional dynamics in individual-atom systems and mesoscopic ensembles. Contrary to previous works, we suggest to excite atoms into different Rydberg states, which results in a potentially richer dynamical behaviour. Specifically, we investigate systems of individual hydrogen-like atoms or mesoscopic ensembles excited into high-lying hydrogen-like s, p or d states and show how to perform three-qubit conditional dynamics on the information they contain through a proper use of dipole-dipole interaction induced energy shifts.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:04:11 GMT" } ]
2009-11-13T00:00:00
[ [ "Brion", "E.", "" ], [ "Mouritzen", "A. S.", "" ], [ "Molmer", "K.", "" ] ]
0706.0148
Dharam Lal Vir
Dharam Vir Lal and Luis C. Ho
The radio properties of type II quasars
4 pages, 3 figures, To appear in "The Central Engine of Active Galactic Nuclei", ed. L. C. Ho and J.-M. Wang (San Francisco: ASP)
A.S.P.Conf.Ser.373:479, 2007
null
null
astro-ph
null
Quasars (of type I) are the luminous analogs of type I Seyfert galaxies. Within the framework of unified models of active galaxies, the population of quasars of type II recently discovered with the Sloan Digital Sky Survey are the luminous analogs of type II Seyfert galaxies. Since our knowledge and understanding of the radio properties of these type II quasars are very limited, we have performed Very Large Array observations for a sub-sample of such sources. Our detection rate of 61% is consistent with the detection rate for other AGN samples. We do not find a correlation between radio and [O III] $\lambda$5007 luminosities for these sources. Although the distribution of spectral indices is similar to that of the 3C sources, the lack of dependence of radio luminosity on [O III] $\lambda$5007 luminosity suggests that not all sources in the sample are genuine AGNs.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:01:38 GMT" } ]
2010-01-22T00:00:00
[ [ "Lal", "Dharam Vir", "" ], [ "Ho", "Luis C.", "" ] ]
0706.0149
Dharam Lal Vir
Dharam Vir Lal, Satoki Matsushita and Jeremy Lim
Using Fast-Switching Data to Characterize Atmospheric Phase Fluctuations at the Submillimeter Array
4 pages, 4 figures, To appear in Springer "Astrophysics and Space Science (ApSS)" Journal, special issue ALMA (Dr. Bachiller)
null
null
null
astro-ph
null
For the submillimeter band observations, we have been routinely adopting the calibration cycle time of 20-30 minutes, which is the same as any typical centimeter and millimeter band observations. This cycle time, largely corrects only the instrumental phase fluctuations and there exists residual phase fluctuations, which are attributed to temporal and spatial atmospheric phase fluctuations. Hence, the classical calibration cycle needs closer attention for any future submillimeter band observations. We have therefore obtained fast-switching test data, cycling between three nearby calibrators, using the submillimeter array (SMA) with a cycle time of $\sim$90 sec, in order to understand and optimize the calibration cycle suitably, thereby to achieve the projected sensitivity, angular resolution and dynamic range for the SMA. Here, we present the preliminary results from this study.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:02:00 GMT" } ]
2007-06-04T00:00:00
[ [ "Lal", "Dharam Vir", "" ], [ "Matsushita", "Satoki", "" ], [ "Lim", "Jeremy", "" ] ]
0706.0150
Alberto G. Setti
Stefano Pigola, Marco Rigoli, Alberto G. Setti
Existence and non-existence results for a logistic-type equation on manifolds
31 pages
null
null
null
math.DG
null
We study the steady state solutions of a generalized logistic type equation on a complete Riemannian manifold. We provide sufficient conditions for existence, respectively non-existence of positive solutions, which depend on the relative size of the coefficients and their mutual interaction with the geometry of the manifold, which is mostly taken into account by means of conditions on the volume growth of geodesic balls.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:20:00 GMT" } ]
2007-06-04T00:00:00
[ [ "Pigola", "Stefano", "" ], [ "Rigoli", "Marco", "" ], [ "Setti", "Alberto G.", "" ] ]
0706.0151
Christophe Vignat
C. Vignat and A. Plastino
Central limit theorem, deformed exponentials and superstatistics
14 pages
null
null
null
cond-mat.stat-mech
null
We show that there exists a very natural, superstatistics-linked extension of the central limit theorem (CLT) to deformed exponentials (also called q-Gaussians): This generalization favorably compares with the one provided by S. Umarov and C. Tsallis [arXiv:cond-mat/0703533], since the latter requires a special "q-independence" condition on the data. On the contrary, our CLT proposal applies exactly in the usual conditions in which the classical CLT is used. Moreover, we show that, asymptotically, the q-independence condition is naturally induced by our version of the CLT.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:08:51 GMT" } ]
2007-06-04T00:00:00
[ [ "Vignat", "C.", "" ], [ "Plastino", "A.", "" ] ]
0706.0152
Francesco Giazotto
F. Giazotto, F. Taddei, P. D'Amico, Rosario Fazio, and F. Beltram
Nonequilibrium spin-dependent phenomena in mesoscopic superconductor-normal metal tunnel structures
Published version: 12 pages, 14 figures; new text added and one figure modified
Phys. Rev. B 76, 184518 (2007)
10.1103/PhysRevB.76.184518
null
cond-mat.mes-hall cond-mat.supr-con
null
We analyze the broad range of spin-dependent nonequilibrium transport properties of hybrid systems composed of a normal region tunnel coupled to two superconductors with exchange fields induced by the proximity to thin ferromagnetic layers and highlight its functionalities. By calculating the quasiparticle distribution functions in the normal region we find that they are spin-dependent and strongly sensitive to the relative angle between exchange fields in the two superconductors. The impact of inelastic collisions on their properties is addressed. As a result, the electric current flowing through the system is found to be strongly dependent on the relative angle between exchange fields, giving rise to a huge value of magnetoresistance. Moreover, the current presents a complete spin-polarization in a wide range of bias voltages, even in the quasiequilibrium case. In the nonequilibrium limit we parametrize the distributions with an ``effective`` temperature, which turns out to be strongly spin-dependent, though quite sensitive to inelastic collisions. By tunnel coupling the normal region to an additional superconducting electrode we show that it is possible to implement a spin-polarized current source of both spin species, depending on the bias voltages applied.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:11:04 GMT" }, { "version": "v2", "created": "Wed, 21 Nov 2007 14:25:20 GMT" } ]
2007-11-21T00:00:00
[ [ "Giazotto", "F.", "" ], [ "Taddei", "F.", "" ], [ "D'Amico", "P.", "" ], [ "Fazio", "Rosario", "" ], [ "Beltram", "F.", "" ] ]
0706.0153
Gabriela Ciuperca
Gabriela Ciuperca
The M-estimator in a multi-phase random nonlinear model
19 pages
null
null
null
math.ST math.PR stat.ME stat.TH
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper considers M-estimation of a nonlinear regression model with multiple change-points occuring at unknown times. The multi-phase random design regression model, discontinuous in each change-point, have an arbitrary error $\epsilon$. In the case when the number of jumps is known, the M-estimator of locations of breaks and of regression parameters are studied. These estimators are consistent and the distribution of the regression parameter estimators is Gaussian. The estimator of each change-point converges, with the rate $n^{-1}$, to the smallest minimizer of the independent compound Poisson processes. The results are valid for a large class of error distributions.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:33:22 GMT" }, { "version": "v2", "created": "Fri, 4 Jul 2008 08:43:56 GMT" }, { "version": "v3", "created": "Mon, 22 Sep 2008 08:08:10 GMT" } ]
2008-09-22T00:00:00
[ [ "Ciuperca", "Gabriela", "" ] ]
0706.0154
Duer Wolfgang
Wolfgang D\"ur, Michael J. Bremner and Hans J. Briegel
Quantum simulation of interacting high-dimensional systems: the influence of noise
38 pages, 10 figures
Phys. Rev. A 78, 052325 (2008)
10.1103/PhysRevA.78.052325
null
quant-ph
null
We consider the simulation of interacting high-dimensional systems using pairwise interacting qubits. The main tool in this context is the generation of effective many-body interactions, and we examine a number of different protocols for obtaining them. These methods include the usage of higher-order processes (commutator method), unitary conjugation or graph state encoding, as well as teleportation based approaches. We illustrate and compare these methods in detail and analyze the time cost for simulation. In the second part of the article, we investigate the influence of noise on the simulation process. We concentrate on errors in the interaction Hamiltonians and consider two generic noise models, (i) timing errors in pairwise interactions and (ii) noisy pairwise interactions described by Master equations of Lindblad form. We analyze and compare the effect of noise for the different simulation methods and propose a way to significantly reduce the influence of noise by making use of entanglement purification together with a teleportation based protocol.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:24:19 GMT" } ]
2010-03-04T00:00:00
[ [ "Dür", "Wolfgang", "" ], [ "Bremner", "Michael J.", "" ], [ "Briegel", "Hans J.", "" ] ]
0706.0155
Arnold Neumaier
Arnold Neumaier
A simple hidden variable experiment
10 pages, 3 figures. Compared to previous versions, an extended discussion is given and many references are added
null
null
null
quant-ph
null
An experiment is described which proves, using single photons only, that the standard hidden variables assumptions (commonly used to derive Bell inequalities) are inconsistent with quantum mechanics. The analysis is very simple and transparent. In particular, it demonstrates that a classical wave model for quantum mechanics is not ruled out by experiments demonstrating the violation of the traditional hidden variable assumptions.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:27:30 GMT" }, { "version": "v2", "created": "Tue, 19 Jun 2007 16:22:32 GMT" }, { "version": "v3", "created": "Fri, 22 Jun 2007 10:15:23 GMT" } ]
2007-06-22T00:00:00
[ [ "Neumaier", "Arnold", "" ] ]
0706.0156
Liane Gabora
Liane Gabora and Diederik Aerts
A Cross-disciplinary Framework for the Description of Contextually Mediated Change
19 pages. arXiv admin note: substantial text overlap with arXiv:q-bio/0511007
null
10.1142/9789812779953_0005
null
physics.gen-ph physics.bio-ph physics.pop-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a mathematical framework (referred to as Context-driven Actualization of Potential, or CAP) for describing how entities change over time under the influence of a context. The approach facilitates comparison of change of state of entities studied in different disciplines. Processes are seen to differ according to the degree of nondeterminism, and the degree to which they are sensitive to, internalize, and depend upon a particular context. Our analysis suggests that the dynamical evolution of a quantum entity described by the Schrodinger equation is not fundamentally different from change provoked by a measurement often referred to as collapse, but a limiting case, with only one way to collapse. The biological transition to coded replication is seen as a means of preserving structure in the fact of context-driven change, and sextual replication as a means of increasing potentiality thus enhancing diversity through interaction with context. The framework sheds light on concepts like selection and fitness, reveals how exceptional Darwinian evolution is as a means of 'change of state', and clarifies in what sense culture, and the creative process underlying it, are Darwinian.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 01:53:42 GMT" }, { "version": "v2", "created": "Sun, 30 Jun 2019 01:26:58 GMT" }, { "version": "v3", "created": "Fri, 5 Jul 2019 22:26:44 GMT" } ]
2019-07-09T00:00:00
[ [ "Gabora", "Liane", "" ], [ "Aerts", "Diederik", "" ] ]
0706.0157
Arnaud Bodin
Arnaud Bodin
Number of irreducible polynomials in several variables over finite fields
A note for American Mathematical Monthly. v2: Correction of an error found out by Dan Velleman
null
null
null
math.AC math.AG math.CO
null
We give a formula and an estimation for the number of irreducible polynomials in two (or more) variables over a finite field.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:34:29 GMT" }, { "version": "v2", "created": "Mon, 11 Jun 2007 11:43:16 GMT" } ]
2007-06-11T00:00:00
[ [ "Bodin", "Arnaud", "" ] ]
0706.0158
Jean-Marc Richard
J.M. Richard (LPSC)
Charmonium singlets, open charm and exotic hadrons
Talk given at the DIS 2007 Conference, Munich Germany, April 2007 - To be published in the proceedings - Typos corrected, references added
Dans Proceedings of the DIS 2007 - DIS 2007 : 15th International Workshop on Deep Inelastic Scattering and Related Subjects, Munich : Allemagne (2007)
null
null
hep-ph
null
Caution is suggested on the comparison of the spin-singlet charmonium P-state with the centre of gravity of triplet states, when the mass splitting is of the order of a few MeV. The physics of new hidden-charm states X and Y is briefly reviewed. Perspectives for producing double-charm baryons and double-charm exotic mesons are discussed.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:42:20 GMT" }, { "version": "v2", "created": "Wed, 13 Jun 2007 08:08:31 GMT" } ]
2011-11-10T00:00:00
[ [ "Richard", "J. M.", "", "LPSC" ] ]
0706.0159
V. V. Kabanov
A. S. Alexandrov and V. V. Kabanov
Combination quantum oscillations in canonical single-band Fermi liquids
null
Phys. Rev. B76, 233101 (2007)
10.1103/PhysRevB.76.233101
null
cond-mat.mes-hall cond-mat.stat-mech
null
Chemical potential oscillations mix individual-band frequencies of the de Haas-van Alphen (dHvA) and Shubnikov-de Haas (SdH) magneto-oscillations in canonical low-dimensional multi-band Fermi liquids. We predict a similar mixing in canonical single-band Fermi liquids, which Fermi-surfaces have two or more extremal cross-sections. Combination harmonics are analysed using a single-band almost two-dimensional energy spectrum. We outline some experimental conditions allowing for resolution of combination harmonics.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:43:40 GMT" } ]
2009-11-13T00:00:00
[ [ "Alexandrov", "A. S.", "" ], [ "Kabanov", "V. V.", "" ] ]
0706.0160
Vladimir Turaev
Vladimir Turaev
Dijkgraaf-Witten invariants of surfaces and projective representations of groups
second version: a mistake corrected in the non-orientable case and a few improvements added
null
10.1016/j.geomphys.2007.08.009
null
math.GT math.RT
null
We compute the Dijkgraaf-Witten invariants of surfaces in terms of projective representations of groups. As an application we prove that the complex Dijkgraaf-Witten invariants of surfaces of positive genus are positive integers.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 13:47:38 GMT" }, { "version": "v2", "created": "Thu, 28 Jun 2007 11:32:20 GMT" } ]
2009-11-13T00:00:00
[ [ "Turaev", "Vladimir", "" ] ]
0706.0161
Bang-Rong Zhou
Xiao-Ming Wang, Bang-Rong Zhou
Electrical Neutrality and Symmetry Restoring Phase Transitions at High Density in a Two-Flavor Nambu-Jona-Lasinio Model
9 pages, 1 figure
Commun.Theor. Phys.47:1081,2007
10.1088/0253-6102/47/6/024
null
hep-ph
null
A general research on chiral symmetry restoring phase transitions at zero temperature and finite chemical potentials under electrical neutrality condition has been conducted in a Nambu-Jona-Lasinio model to describe two-flavor normal quark matter. Depending on that $m_0/\Lambda$, the ratio of dynamical quark mass in vacuum and the 3D momentum cutoff in the loop integrals, is less or greater than 0.413, the phase transition will be second or first order. A complete phase diagram of $u$ quark chemical potential versus $m_0$ is given. With the electrical neutrality constraint, the region where second order phase transition happens will be wider than the one without electrical neutrality limitation. The results also show that, for the value of $m_0/\Lambda$ from QCD phenomenology, the phase transition must be first order.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 14:14:49 GMT" } ]
2009-03-19T00:00:00
[ [ "Wang", "Xiao-Ming", "" ], [ "Zhou", "Bang-Rong", "" ] ]
0706.0162
Rowan Thomson
Robert C. Myers, Andrei O. Starinets, and Rowan M. Thomson
Holographic spectral functions and diffusion constants for fundamental matter
LaTex, 66 pages, 18 figures, final version
JHEP 0711:091,2007
10.1088/1126-6708/2007/11/091
null
hep-th
null
The holographic dual of large-Nc super-Yang-Mills coupled to a small number of flavours of fundamental matter, Nf << Nc, is described by Nf probe D7-branes in the gravitational background of Nc black D3-branes. This system undergoes a first order phase transition characterised by the `melting' of the mesons. We study the high temperature phase in which the D7-branes extend through the black hole horizon. In this phase, we compute the spectral function for vector, scalar and pseudoscalar modes on the D7-brane probe. We also compute the diffusion constant for the flavour currents.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 14:50:37 GMT" }, { "version": "v2", "created": "Mon, 24 Sep 2007 18:42:54 GMT" }, { "version": "v3", "created": "Thu, 25 Oct 2007 12:19:53 GMT" } ]
2009-03-20T00:00:00
[ [ "Myers", "Robert C.", "" ], [ "Starinets", "Andrei O.", "" ], [ "Thomson", "Rowan M.", "" ] ]
0706.0163
Alexander K. Vidybida
Alexander K. Vidybida
Output Stream of Binding Neuron with Feedback
Version #1: 4 pages, 5 figures, manuscript submitted to Biological Cybernetics. Version #2 (this version): added 3 pages of new text with additional analytical and numerical calculations, 2 more figures, 11 more references, added Discussion section
Eur. Phys. J. B 65, 577-584 (2008); Eur. Phys. J. B 69, 313 (2009)
10.1140/epjb/e2008-00360-1
null
q-bio.NC q-bio.OT
null
The binding neuron model is inspired by numerical simulation of Hodgkin-Huxley-type point neuron, as well as by the leaky integrate-and-fire model. In the binding neuron, the trace of an input is remembered for a fixed period of time after which it disappears completely. This is in the contrast with the above two models, where the postsynaptic potentials decay exponentially and can be forgotten only after triggering. The finiteness of memory in the binding neuron allows one to construct fast recurrent networks for computer modeling. Recently, the finiteness is utilized for exact mathematical description of the output stochastic process if the binding neuron is driven with the Poissonian input stream. In this paper, the simplest networking is considered for binding neuron. Namely, it is expected that every output spike of single neuron is immediately fed into its input. For this construction, externally fed with Poissonian stream, the output stream is characterized in terms of interspike interval probability density distribution if the binding neuron has threshold 2. For higher thresholds, the distribution is calculated numerically. The distributions are compared with those found for binding neuron without feedback, and for leaky integrator. Sample distributions for leaky integrator with feedback are calculated numerically as well. It is oncluded that even the simplest networking can radically alter spikng statistics. Information condensation at the level of single neuron is discussed.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 14:20:19 GMT" }, { "version": "v2", "created": "Tue, 25 Sep 2007 15:00:26 GMT" } ]
2011-07-20T00:00:00
[ [ "Vidybida", "Alexander K.", "" ] ]
0706.0164
Isabel P\'erez-Arjona
Isabel Perez-Arjona, Victor J. Sanchez-Morcillo, Eugenio Roldan
Cavity solitons in bidirectional lasers
4 figures
null
10.1364/OL.32.003221
null
nlin.PS
null
We show theoretically that a broad area bidirectional laser with slightly different cavity losses for the two counterpropagating fields sustains cavity solitons (CSs). These structures are complementary, i.e., there is a bright (dark) CS in the field with more (less) losses. Interestingly, the CSs can be written/erased by injecting suitable pulses in any of the two counterpropagating fields.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 14:27:19 GMT" } ]
2009-11-13T00:00:00
[ [ "Perez-Arjona", "Isabel", "" ], [ "Sanchez-Morcillo", "Victor J.", "" ], [ "Roldan", "Eugenio", "" ] ]
0706.0165
Dominik Schwarz
Dominik J. Schwarz and Bastian Weinhorst
(An)isotropy of the Hubble diagram: comparing hemispheres
13 pages, 8 figures; several corrections - conclusions unchanged; matches published version
Astron.Astrophys.474:717-729,2007
10.1051/0004-6361:20077998
BI-TP 2007/08
astro-ph
null
We test the isotropy of the Hubble diagram. At small redshifts, this is possible without assumptions on the cosmic inventory and provides a fundamental test of the cosmological principle. At higher redshift we check for the self-consistency of the LambdaCDM model. At small redshifts, we use public supernovae (SNe) Ia data to determine the deceleration parameter q_0 and the SN calibration on opposite hemispheres. For the complete data sets we fit Omega_M and the SN calibration on opposite hemispheres. A statistically significant anisotropy of the Hubble diagram at redshifts z < 0.2 is discovered (> 95% C.L.). While data from the North Galactic hemisphere favour the accelerated expansion of the Universe, data from the South Galactic hemisphere are not conclusive. The hemispheric asymmetry is maximal toward a direction close to the equatorial poles. The discrepancy between the equatorial North and South hemispheres shows up in the SN calibration. For the LambdaCDM model fitted to all available SNe, we find the same asymmetry. The alignment of discrepancies between hemispheric Hubble diagrams with the equatorial frame seems to point toward a systematic error in the SN search, observation, analysis or data reduction. We also find that our model independent test cannot exclude the case of the deceleration of the expansion at a statistically significant level.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:00:08 GMT" }, { "version": "v2", "created": "Wed, 12 Sep 2007 12:34:30 GMT" } ]
2011-07-28T00:00:00
[ [ "Schwarz", "Dominik J.", "" ], [ "Weinhorst", "Bastian", "" ] ]
0706.0166
Walid Hachem
Walid Hachem (LTCI), Philippe Loubaton (IGM-LabInfo), Jamal Najim (LTCI)
A CLT for Information-theoretic statistics of Gram random matrices with a given variance profile
null
null
null
null
math.PR
null
Consider a $N\times n$ random matrix $Y_n=(Y_{ij}^{n})$ where the entries are given by $$ Y_{ij}^{n}=\frac{\sigma_{ij}(n)}{\sqrt{n}} X_{ij}^{n} $$ the $X_{ij}^{n}$ being centered, independent and identically distributed random variables with unit variance and $(\sigma_{ij}(n); 1\le i\le N, 1\le j\le n)$ being an array of numbers we shall refer to as a variance profile. We study in this article the fluctuations of the random variable $$ \log\det(Y_n Y_n^* + \rho I_N) $$ where $Y^*$ is the Hermitian adjoint of $Y$ and $\rho > 0$ is an additional parameter. We prove that when centered and properly rescaled, this random variable satisfies a Central Limit Theorem (CLT) and has a Gaussian limit whose parameters are identified. A complete description of the scaling parameter is given; in particular it is shown that an additional term appears in this parameter in the case where the 4$^\textrm{th}$ moment of the $X_{ij}$'s differs from the 4$^{\textrm{th}}$ moment of a Gaussian random variable. Such a CLT is of interest in the field of wireless communications.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 14:43:35 GMT" } ]
2007-06-04T00:00:00
[ [ "Hachem", "Walid", "", "LTCI" ], [ "Loubaton", "Philippe", "", "IGM-LabInfo" ], [ "Najim", "Jamal", "", "LTCI" ] ]
0706.0167
Emmanuel Humbert
Emmanuel Humbert (IECN)
Extremal functions for the sharp $L^2-$ Nash inequality
null
Calculus of Variations and Partial Differential Equations 22, No 1 (2005) p 21-44
null
null
math.DG
null
We give geometrical conditions under which there exist extremal functions for the sharp $L^2$-Nash inequality.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 14:44:23 GMT" } ]
2007-06-04T00:00:00
[ [ "Humbert", "Emmanuel", "", "IECN" ] ]
0706.0168
Michele Tumminello
Michele Tumminello, Fabrizio Lillo, Rosario Nunzio Mantegna
Kullback-Leibler distance as a measure of the information filtered from multivariate data
13 pages, 6 figures
Phys. Rev. E 76, 031123 (2007)
10.1103/PhysRevE.76.031123
null
physics.data-an physics.soc-ph q-fin.ST
null
We show that the Kullback-Leibler distance is a good measure of the statistical uncertainty of correlation matrices estimated by using a finite set of data. For correlation matrices of multivariate Gaussian variables we analytically determine the expected values of the Kullback-Leibler distance of a sample correlation matrix from a reference model and we show that the expected values are known also when the specific model is unknown. We propose to make use of the Kullback-Leibler distance to estimate the information extracted from a correlation matrix by correlation filtering procedures. We also show how to use this distance to measure the stability of filtering procedures with respect to statistical uncertainty. We explain the effectiveness of our method by comparing four filtering procedures, two of them being based on spectral analysis and the other two on hierarchical clustering. We compare these techniques as applied both to simulations of factor models and empirical data. We investigate the ability of these filtering procedures in recovering the correlation matrix of models from simulations. We discuss such an ability in terms of both the heterogeneity of model parameters and the length of data series. We also show that the two spectral techniques are typically more informative about the sample correlation matrix than techniques based on hierarchical clustering, whereas the latter are more stable with respect to statistical uncertainty.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 14:51:28 GMT" } ]
2008-12-02T00:00:00
[ [ "Tumminello", "Michele", "" ], [ "Lillo", "Fabrizio", "" ], [ "Mantegna", "Rosario Nunzio", "" ] ]
0706.0169
Hoang Hiep Pham
Per Ahag, Urban Cegrell, Rafal Czyz and Pham Hoang Hiep
Monge-Ampere measures on pluripolar sets
This is a revised version
null
null
null
math.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this article we solve the complex Monge-Ampere equation for measures with large singular part. This result generalizes classical results by Demailly, Lelong and Lempert a.o., who considered singular parts carried on discrete sets. By using our result we obtain a generalization of Kolodziej's subsolution theorem. More precisely, we prove that if a non-negative Borel measure is dominated by a complex Monge-Ampere measure, then it is a complex Monge-Ampere measure.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 14:54:41 GMT" }, { "version": "v2", "created": "Tue, 27 May 2008 10:09:26 GMT" }, { "version": "v3", "created": "Tue, 19 Aug 2008 12:40:08 GMT" } ]
2008-08-19T00:00:00
[ [ "Ahag", "Per", "" ], [ "Cegrell", "Urban", "" ], [ "Czyz", "Rafal", "" ], [ "Hiep", "Pham Hoang", "" ] ]
0706.0170
Tullio Scopigno
Tullio Scopigno, Spyros Yannopoulos, Filippo Scarponi, Kostas Andrikopoulos, Daniele Fioretto and Giancarlo Ruocco
On the origin of the $\lambda$-transition in liquid Sulphur
5 pages, 4 eps figures, accepted in Phys. Rev. Lett
null
10.1103/PhysRevLett.99.025701
null
cond-mat.dis-nn cond-mat.soft
null
Developing a novel experimental technique, we applied photon correlation spectroscopy using infrared radiation in liquid Sulphur around $T_\lambda$, i.e. in the temperature range where an abrupt increase in viscosity by four orders of magnitude is observed upon heating within few degrees. This allowed us - overcoming photo-induced and absorption effects at visible wavelengths - to reveal a chain relaxation process with characteristic time in the ms range. These results do rehabilitate the validity of the Maxwell relation in Sulphur from an apparent failure, allowing rationalizing the mechanical and thermodynamic behavior of this system within a viscoelastic scenario.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:03:24 GMT" } ]
2009-11-13T00:00:00
[ [ "Scopigno", "Tullio", "" ], [ "Yannopoulos", "Spyros", "" ], [ "Scarponi", "Filippo", "" ], [ "Andrikopoulos", "Kostas", "" ], [ "Fioretto", "Daniele", "" ], [ "Ruocco", "Giancarlo", "" ] ]
0706.0171
Danielle Rojas-Rousse
Danielle Rousse (IRBII)
Persistent pods of the tree Acacia caven: a natural refuge for diverse insects including Bruchid beetles and the parasitoids Trichogrammatidae, Pteromalidae and Eulophidae
9 pages
Journal of Insect Science, 8 (12/06/2006) 1-9 pages
null
www.insectscience.org ISSN:1536-2442
q-bio.PE
null
The persistent pods of the tree, Acacia caven, that do not fall from the tree provide opportunities for the appearance of a diverse group of insects the following season. Such pods collected during the spring of 1999 in Chile were indehiscent with highly sclerified pod walls. In contrast, persistent pods collected in Uruguay after a wet winter and spring (2002) were partially dehiscent, inducing the deterioration of the woody pods, and consequently exposing the seeds. These persistent pods are a natural refuge for insect species, namely two bruchid beetles (Pseudopachymeria spinipes, Stator furcatus), one scolytidae (Dendroctonus sp), lepidopterous larvae, ant colonies (Camponotus sp),one species of oophagous parasitoid (Uscana espinae group senex), the gregarious larval-pupae parasitoid Monoksa dorsiplana (Pteromalidae) and two species of Horismenus spp. (Eulophidae). The patriline of M. dorsiplana is frequently formed by 1 son +7 daughters.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:04:59 GMT" } ]
2007-06-04T00:00:00
[ [ "Rousse", "Danielle", "", "IRBII" ] ]
0706.0172
Emmanuel Humbert
Pascal H\'ebrard (IECN), Emmanuel Humbert (IECN)
The geometrical quantity in damped wave equations on a square
null
ESAIM - Control Optimisation and Calculs of Variations 12, 4 (31/12/2006) 636-661
null
null
math.DG
null
The energy in a square membrane $\Omega$ subject to constant viscous damping on a subset $\omega\subset \Omega$ decays exponentially in time as soon as $\omega$ satisfies a geometrical condition known as the "Bardos-Lebeau-Rauch" condition. The rate $\tau(\omega)$ of this decay satisfies $\tau(\omega)= 2 \min(-\mu(\omega), g(\omega))$ (see Lebeau [Math. Phys. Stud. 19 (1996) 73-109]). Here $\mu(\omega)$ denotes the spectral abscissa of the damped wave equation operator and $g(\omega)$ is a number called the geometrical quantity of $\omega$ and defined as follows. A ray in $\Omega$ is the trajectory generated by the free motion of a mass-point in $\Omega$ subject to elastic reflections on the boundary. These reflections obey the law of geometrical optics. The geometrical quantity $g(\omega)$ is then defined as the upper limit (large time asymptotics) of the average trajectory length. We give here an algorithm to compute explicitly $g(\omega)$ when $\omega$ is a finite union of squares.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:09:04 GMT" } ]
2007-06-04T00:00:00
[ [ "Hébrard", "Pascal", "", "IECN" ], [ "Humbert", "Emmanuel", "", "IECN" ] ]
0706.0173
Michele Tumminello
Michele Tumminello, Francesco Ciccarello
Teleportation of atomic states via position measurements
9 pages, 3 figures, 3 new appendices included
Phys. Rev. A 77, 023825 (2008)
10.1103/PhysRevA.77.023825
null
quant-ph
null
We present a scheme for conditionally teleporting an unknown atomic state in cavity QED, which requires two atoms and one cavity mode. The translational degrees of freedom of the atoms are taken into account using the optical Stern-Gerlach model. We show that successful teleportation with probability 1/2 can be achieved through local measurements of the cavity photon number and atomic positions. Neither direct projection onto highly entangled states nor holonomous interaction-time constraints are required.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:15:27 GMT" }, { "version": "v2", "created": "Thu, 28 Feb 2008 13:11:15 GMT" } ]
2008-02-28T00:00:00
[ [ "Tumminello", "Michele", "" ], [ "Ciccarello", "Francesco", "" ] ]
0706.0174
Alfio Bonanno
Alfio Bonanno, Martin Reuter
Entropy signature of the running cosmological constant
57 pages, 7 figures
JCAP 0708:024,2007
10.1088/1475-7516/2007/08/024
MZ-TH/07-10
hep-th astro-ph gr-qc
null
Renormalization group (RG) improved cosmologies based upon a RG trajectory of Quantum Einstein Gravity (QEG) with realistic parameter values are investigated using a system of cosmological evolution equations which allows for an unrestricted energy exchange between the vacuum and the matter sector. It is demonstrated that the scale dependence of the gravitational parameters, the cosmological constant in particular, leads to an entropy production in the matter system. The picture emerges that the Universe started out from a state of vanishing entropy, and that the radiation entropy observed today is essentially due to the coarse graining (RG flow) in the quantum gravity sector which is related to the expansion of the Universe. Furthermore, the RG improved field equations are shown to possess solutions with an epoch of power law inflation immediately after the initial singularity. The inflation is driven by the cosmological constant and ends automatically once the RG running has reduced the vacuum energy to the level of the matter energy density.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:15:54 GMT" }, { "version": "v2", "created": "Sun, 3 Jun 2007 14:37:20 GMT" } ]
2009-11-18T00:00:00
[ [ "Bonanno", "Alfio", "" ], [ "Reuter", "Martin", "" ] ]
0706.0175
Dominik Epple
H. Reinhardt and D. Epple
The 't Hooft loop in the Hamiltonian approach to Yang-Mills theory in Coulomb gauge
32 pages, 4 figures, uses revtex4
Phys.Rev.D76:065015,2007
10.1103/PhysRevD.76.065015
null
hep-th
null
The spatial 't Hooft loop, which is a disorder parameter dual to the temporal Wilson loop, is calculated using the nonperturbative Yang-Mills vacuum wave functional determined previously by a variational solution of the Yang-Mills Schroedinger equation in Coulomb gauge. It is shown, that this wave functional yields indeed a perimeter law for large spatial 't Hooft loops signaling confinement.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:27:09 GMT" }, { "version": "v2", "created": "Fri, 21 Sep 2007 15:35:51 GMT" } ]
2008-11-26T00:00:00
[ [ "Reinhardt", "H.", "" ], [ "Epple", "D.", "" ] ]
0706.0176
Alberto Cortijo
Fernando de Juan, Alberto Cortijo, and Mar\'ia A. H. Vozmediano
Charge inhomogeneities due to smooth ripples in graphene sheets
9 pages, 5 figures. v2: Abstract and discussion about experimental consequences expanded
Phys. Rev. B 76, 165409 (2007)
10.1103/PhysRevB.76.165409
null
cond-mat.str-el cond-mat.mtrl-sci
null
We study the effect of the curved ripples observed in the free standing graphene samples on the electronic structure of the system. We model the ripples as smooth curved bumps and compute the Green's function of the Dirac fermions in the curved surface. Curved regions modify the Fermi velocity that becomes a function of the point on the graphene surface and induce energy dependent oscillations in the local density of states around the position of the bump. The corrections are estimated to be of a few percent of the flat density at the typical energies explored in local probes such as scanning tunnel microscopy that should be able to observe the predicted correlation of the morphology with the electronics. We discuss the connection of the present work with the recent observation of charge anisotropy in graphene and propose that it can be used as an experimental test of the curvature effects.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:27:13 GMT" }, { "version": "v2", "created": "Thu, 28 Jun 2007 17:38:24 GMT" }, { "version": "v3", "created": "Thu, 28 Jun 2007 22:25:16 GMT" } ]
2009-11-13T00:00:00
[ [ "de Juan", "Fernando", "" ], [ "Cortijo", "Alberto", "" ], [ "Vozmediano", "María A. H.", "" ] ]
0706.0177
Servio Perez
H. Paredes Gut\'ierrez, S. T. P\'erez-Merchancano and G. E. Marques
Spin Effect on the Resonant Tunneling Characteristics of a Double-Barrier Heterostructures Under Longitudinal Stresses
9 pages, 2 figures
null
null
null
cond-mat.mes-hall cond-mat.soft
null
Theoretical research on electronic properties in mesoscopic condensed matter systems has focused primarily on the electron charge freedom degrees, while its corresponding spin freedom degrees have not yet received the same attention. Nevertheless nowadays there has been an increment in the number of electron spin-related experiments showing unique possibilities for finding novel mechanisms of information processing and transmission, opening ample fields of opportunities in the theoretical developed of new models. In this spirit we have calculated the resonant tunneling characteristics curves in double-barrier heterostructures of GaAs-Ga1-x AlxAs under external stress and considering two charges with spin half. The resonant tunneling study has been carried out by means of the diagrammatic techniques for non equilibrium processes following the model proposed by Keldysh also a simple one-band tight-binding Hamiltonian is adopted in the theoretical framework. We have compared our results of the spin-tunneling with previous ones reported in literature.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:29:20 GMT" } ]
2016-08-14T00:00:00
[ [ "Gutíerrez", "H. Paredes", "" ], [ "Pérez-Merchancano", "S. T.", "" ], [ "Marques", "G. E.", "" ] ]
0706.0178
Carlos E. Yaguna
Carlos E. Yaguna
Sterile neutrino production in models with low reheating temperatures
16 pages, 13 figures
JHEP 0706:002,2007
10.1088/1126-6708/2007/06/002
null
hep-ph
null
By numerically solving the appropriate Boltzmann equations, we study the production of sterile neutrinos in models with low reheating temperatures. We take into account the production in oscillations as well as in direct decays and compute the sterile neutrino primordial spectrum, the effective number of neutrino species, and the sterile neutrino contribution to the mass density of the Universe as a function of the mixing and the reheating parameters. It is shown that sterile neutrinos with non-negligible mixing angles do not necessarily lead to $N_\nu\sim 4$ and that sterile neutrinos may have the right relic density to explain the dark matter of the Universe. If dark matter consists of sterile neutrinos produced in oscillations, X-rays measurements set a strong limit on the reheating temperature, $\tr\gtrsim 7\mev$. We also point out that the direct decay opens up a new production mechanism for sterile neutrino dark matter where cosmological constraints can be satisfied.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:34:58 GMT" } ]
2009-11-13T00:00:00
[ [ "Yaguna", "Carlos E.", "" ] ]
0706.0179
Mairi Sakellariadou
William Nelson and Mairi Sakellariadou (King's College, London)
Lattice Refining Loop Quantum Cosmology and Inflation
12 pages, RevTex Two minor changes to match version to appear in Physical Review D
Phys.Rev.D76:044015,2007
10.1103/PhysRevD.76.044015
null
gr-qc astro-ph hep-ph hep-th
null
We study the importance of lattice refinement in achieving a successful inflationary era. We solve, in the continuum limit, the second order difference equation governing the quantum evolution in loop quantun cosmology, assuming both a fixed and a dynamically varying lattice in a suitable refinement model. We thus impose a constraint on the potential of a scalar field, so that the continuum approximation is not broken. Considering that such a scalar field could play the role of the inflaton, we obtain a second constraint on the inflationary potential so that there is consistency with the CMB data on large angular scales. For a $m^2\phi^2/2$ inflationary model, we combine the two constraints on the inflaton potential to impose an upper limit on $m$, which is severely fine-tuned in the case of a fixed lattice. We thus conclude that lattice refinement is necessary to achieve a natural inflationary model.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:40:37 GMT" }, { "version": "v2", "created": "Sat, 30 Jun 2007 08:59:10 GMT" } ]
2008-11-26T00:00:00
[ [ "Nelson", "William", "", "King's College, London" ], [ "Sakellariadou", "Mairi", "", "King's College, London" ] ]
0706.0180
Andrew N. Jordan
Andrew N. Jordan, Bjoern Trauzettel, and Guido Burkard
Weak measurement of quantum dot spin qubits
8 pages, 2 figures
Phys. Rev. B 76, 155324 (2007)
10.1103/PhysRevB.76.155324
null
cond-mat.mes-hall quant-ph
null
The theory of weak quantum measurements is developed for quantum dot spin qubits. Building on recent experiments, we propose a control cycle to prepare, manipulate, weakly measure, and perform quantum state tomography. This is accomplished using a combination of the physics of electron spin resonance, spin blockade, and Coulomb blockade, resulting in a charge transport process. We investigate the influence of the surrounding nuclear spin environment, and find a regime where this environment significantly simplifies the dynamics of the weak measurement process, making this theoretical proposal realistic with existing experimental technology. We further consider spin-echo refocusing to combat dephasing, as well as discuss a realization of "quantum undemolition", whereby the effects of quantum state disturbance are undone.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:40:44 GMT" } ]
2007-10-25T00:00:00
[ [ "Jordan", "Andrew N.", "" ], [ "Trauzettel", "Bjoern", "" ], [ "Burkard", "Guido", "" ] ]
0706.0181
Jos\'e Ram\'on Salgueiro
Jose R. Salgueiro and Yuri S. Kivshar
Switching of optical vortices in nonlinear annular couplers
3 pages, 5 figures
null
null
null
nlin.PS physics.optics
null
We suggest an annular waveguide coupler for switching the angular momentum of light. We study linear and nonlinear coupling of both power and momentum of an optical vortex beam launched into one of the ring cores, and demonstrate that the switching takes place well below the collapse threshold. The switching is more effective for the inner-ring excitation since it triggers more sharply and for the lower power enough to avoid the beam azimuthal instability.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:49:00 GMT" } ]
2007-06-04T00:00:00
[ [ "Salgueiro", "Jose R.", "" ], [ "Kivshar", "Yuri S.", "" ] ]
0706.0182
Jana Ma\v{r}\'ikov\'a
Jana Ma\v{r}\'ikov\'a
The structure on the real field generated by the standard part map on an o-minimal expansion of a real closed field
null
null
null
null
math.LO
null
Let R be a sufficiently saturated o-minimal expansion of a real closed field, let O be the convex hull of the rationals in R, and let st: O^n \to \mathbb{R}^n be the standard part map. For X \subseteq R^n define st(X):=st(X \cap O^n). We let \mathbb{R}_{\ind} be the structure with underlying set \mathbb{R} and expanded by all sets of the form st(X), where X \subseteq R^{n} is definable in R and n=1,2,.... We show that the subsets of \mathbb{R}^n that are definable in \mathbb{R}_{\ind} are exactly the finite unions of sets of the form st(X) \setminus st(Y), where X,Y \subseteq R^n are definable in R. A consequence of the proof is a partial answer to a question by Hrushovski, Peterzil and Pillay about the existence of measures with certain invariance properties on the lattice of bounded definable sets in R^n.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:57:20 GMT" } ]
2007-06-04T00:00:00
[ [ "Maříková", "Jana", "" ] ]
0706.0183
Ulf-G. Mei{\ss}ner
A. Sibirtsev, J. Haidenbauer, S. Krewald, T.-S.H. Lee, U.-G. Mei{\ss}ner and A.W. Thomas
Regge approach to charged-pion photoproduction at invariant energies above 2 GeV
misprint in Table 3 corrected; reference added
Eur.Phys.J.A34:49-68,2007
10.1140/epja/i2007-10482-6
FZJ-IKP-TH-2007-19, HISKP-TH-07/16, JLAB-THY-07-639
nucl-th
null
A Regge model with absorptive corrections is employed in a global analysis of the world data on positive and negative pion photoproduction for photon energies from 3 to 8 GeV. In this region resonance contributions are expected to be negligible so that the available experimental information on differential cross sections and single polarization observables at -t \leq 2 GeV^2 allows us to determine the non-resonant part of the reaction amplitude reliably. The model amplitude is then used to predict observables for photon energies below 3 GeV. Differences between our predictions and data in this energy region are systematically examined as possible signals for the presence of excited baryons. We find that the data available for the polarized photon asymmetry show promising resonance signatures at invariant energies around 2 GeV. With regard to differential cross sections the analysis of negative pion photoproduction data, obtained recently at JLab, indicates likewise the presence of resonance structures around 2 GeV
[ { "version": "v1", "created": "Fri, 1 Jun 2007 15:57:59 GMT" }, { "version": "v2", "created": "Tue, 18 Sep 2007 10:23:51 GMT" } ]
2008-11-26T00:00:00
[ [ "Sibirtsev", "A.", "" ], [ "Haidenbauer", "J.", "" ], [ "Krewald", "S.", "" ], [ "Lee", "T. -S. H.", "" ], [ "Meißner", "U. -G.", "" ], [ "Thomas", "A. W.", "" ] ]
0706.0184
Javier Daniel Fuhr
Javier D. Fuhr, Blas Alascio, Michel Avignon
Pressure induced Insulator-Metal transition in LaMnO$_3$
7 pages, 5 figures
null
null
null
cond-mat.str-el
null
The recent observation of a insulator to metal transition (IMT) [I. Loa et al, PRL 87, 125501 (2001)] in pure LaMnO$_3$ at 32 GPa and room temperature, well above the Neel temperature (145 K) and below the Jahn-Teller transition temperature (780 K), opens the way to a study of the role of the orbital degrees of freedom on the electronic structure in a stoichiometric material. In this paper we focus our attention in the orbital aspects of the insulator to metal transition. We use a model Hamiltonian for the $e_g$ orbitals of Mn that includes the on site Coulomb repulsion $U$, the hopping $t$, and its dependence with pressure. In order to include in an appropriate way the strong correlations induced by the dominant electron-electron interactions we introduce auxiliary fields (Slave Bosons,SB) to the description of the low energy states. We use a O-Mn distance ($d$) dependence of $t$ and the pressure-$d$ relation from the experimental data to describe the evolution of the electronic structure with pressure. Our results confirm and make transparent the conclusion reached in previous ab-initio calculations: the inclusion of the Coulomb energy is necessary and constitutes an important factor enhancing the orbital polarization in these compounds.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:42:19 GMT" } ]
2009-04-16T00:00:00
[ [ "Fuhr", "Javier D.", "" ], [ "Alascio", "Blas", "" ], [ "Avignon", "Michel", "" ] ]
0706.0185
Xianghong Qi
Xianghong Qi and John J. Portman
Excluded volume, local structural cooperativity,and the polymer physics of protein folding rates
12 pages,6 figures,1 page supporting information.To be published in Proc.Natl.Acad.Sci.(USA)(2007)
null
10.1073/pnas.0609321104
null
q-bio.BM physics.bio-ph physics.chem-ph
null
A coarse-grained variational model is used to investigate the polymer dynamics of barrier crossing for a diverse set of two-state folding proteins. The model gives reliable folding rate predictions provided excluded volume terms that induce minor structural cooperativity are included in the interaction potential. In general, the cooperative folding routes have sharper interfaces between folded and unfolded regions of the folding nucleus and higher free energy barriers. The calculated free energy barriers are strongly correlated with native topology as characterized by contact order. Increasing the rigidity of the folding nucleus changes the local structure of the transition state ensemble non-uniformly across the set of protein studied. Neverthless, the calculated prefactors k0 are found to be relatively uniform across the protein set, with variation in 1/k0 less than a factor of five. This direct calculation justifies the common assumption that the prefactor is roughly the same for all small two-state folding proteins. Using the barrier heights obtained from the model and the best fit monomer relaxation time 30ns, we find that 1/k0 (1-5)us (with average 1/k0 4us). This model can be extended to study subtle aspects of folding such as the variation of the folding rate with stability or solvent viscosity, and the onset of downhill folding.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 16:17:49 GMT" } ]
2009-11-13T00:00:00
[ [ "Qi", "Xianghong", "" ], [ "Portman", "John J.", "" ] ]
0706.0186
Laura Lopez Honorez
Laura Lopez Honorez
Dark Matter from the Inert Doublet Model
Proceedings for the ``Rencontres de Moriond: Electroweak Interactions and Unified Theories'' (2007)
null
null
ULB-TH/07-21
hep-ph
null
The Inert Doublet Model is an extension of the Standard Model including one extra ``Inert scalar doublet'' and an exact $Z_2$ symmetry. The ``Inert scalar'' provides a new candidate for dark matter. We present a systematic analysis of the dark matter abundance assuming the standard freeze-out mechanism and investigate the potentialities for direct and gamma indirect detection. We show that the dark matter candidate saturates the WMAP dark matter density in two rather separate mass ranges, one between 40 and 80 GeV, the other one over 400 GeV. We also show that the model should be within the range of future experiments, like GLAST and EDELWEISS II or ZEPLIN.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 16:42:12 GMT" } ]
2007-06-04T00:00:00
[ [ "Honorez", "Laura Lopez", "" ] ]
0706.0187
Alexandre Losev
A. Losev
Modelling Quasicrystals
4 pages, 4 figures; a slightly modified v2 to be published as' Wave models of non-crystallographic structures' in the Philosophical Magazine
null
null
null
cond-mat.other
null
A new kind of aperiodic tiling is introduced. It is shown to underlie a structure obtained as a superposition of waves with incommensurate periods. Its connections to other other tilings and quasicrystals are discussed.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 16:46:51 GMT" }, { "version": "v2", "created": "Wed, 28 Nov 2007 08:40:37 GMT" } ]
2007-11-28T00:00:00
[ [ "Losev", "A.", "" ] ]
0706.0188
Tatsuma Nishioka
Masanori Hanada and Tatsuma Nishioka
Cascade of Gregory-Laflamme Transitions and U(1) Breakdown in Super Yang-Mills
15 pages, 3 figures, LaTeX, v2: comments and references added, v3: minor changes and a reference added
JHEP 0709:012,2007
10.1088/1126-6708/2007/09/012
KUNS-2075, RIKEN-TH 101
hep-th gr-qc
null
In this paper we consider black p-branes on square torus. We find an indication of a cascade of Gregory-Laflamme transitions between black p-brane and (p-1)-brane. Through AdS/CFT correspondence, these transitions are related to the breakdown of the U(1) symmetry in super Yang-Mills on torus. We argue a relationship between the cascade and recent Monte-Carlo data.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 16:52:32 GMT" }, { "version": "v2", "created": "Mon, 11 Jun 2007 05:10:08 GMT" }, { "version": "v3", "created": "Sat, 1 Sep 2007 02:25:44 GMT" } ]
2009-04-30T00:00:00
[ [ "Hanada", "Masanori", "" ], [ "Nishioka", "Tatsuma", "" ] ]
0706.0189
Colin Cotter
C. J. Cotter and G. J. Gorman
Diagnostic tools for 3D unstructured oceanographic data
null
null
10.1016/j.ocemod.2007.08.004
null
physics.ao-ph
null
Most ocean models in current use are built upon structured meshes. It follows that most existing tools for extracting diagnostic quantities (volume and surface integrals, for example) from ocean model output are constructed using techniques and software tools which assume structured meshes. The greater complexity inherent in unstructured meshes (especially fully unstructured grids which are unstructured in the vertical as well as the horizontal direction) has left some oceanographers, accustomed to traditional methods, unclear on how to calculate diagnostics on these meshes. In this paper we show that tools for extracting diagnostic data from the new generation of unstructured ocean models can be constructed with relative ease using open source software. Higher level languages such as Python, in conjunction with packages such as NumPy, SciPy, VTK and MayaVi, provide many of the high-level primitives needed to perform 3D visualisation and evaluate diagnostic quantities, e.g. density fluxes. We demonstrate this in the particular case of calculating flux of vector fields through isosurfaces, using flow data obtained from the unstructured mesh finite element ocean code ICOM, however this tool can be applied to model output from any unstructured grid ocean code.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 16:54:31 GMT" }, { "version": "v2", "created": "Tue, 7 Aug 2007 15:02:22 GMT" } ]
2015-05-13T00:00:00
[ [ "Cotter", "C. J.", "" ], [ "Gorman", "G. J.", "" ] ]
0706.0190
Hou Yau
Hou Y. Yau
Quantum Properties and Gravitational Field of a System with Oscillations in Time
16 pages, no figures
null
null
null
physics.gen-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the quantum properties and gravitational field of a system that has oscillations in time. Treating time as a dynamical variable, we first construct a wave with 4-vector amplitude that has matters vibrating in space and time. By analyzing its Hamiltonian density equation, we find that such system shall be treated as a quantized field. This quantized real scalar field obeys the Klein-Gordon equation and has properties resemble a zero spin bosonic field. In addition, the particle observed has oscillation in proper time. By neglecting all quantum effects and assuming the particle as a classical object that can remain stationary in space, we show that the spacetime geometry around the proper time oscillation has properties similar to the Schwarzschild gravitational field of a point mass in relativity.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 16:55:34 GMT" }, { "version": "v2", "created": "Tue, 13 Nov 2007 22:47:07 GMT" }, { "version": "v3", "created": "Mon, 12 Jan 2009 17:15:59 GMT" }, { "version": "v4", "created": "Fri, 20 May 2016 03:17:04 GMT" } ]
2016-05-23T00:00:00
[ [ "Yau", "Hou Y.", "" ] ]
0706.0191
Zhongzu Wu
Zhongzu Wu, D. R. Jiang, Minfeng Gu, Yi Liu
VLBI observations of seven BL Lac objects from RGB sample
22 pages,15figures, published by A&A
Astron.Astrophys.63:466,2007
10.1051/0004-6361:20066754
null
astro-ph
null
We present EVN observations of seven BL Lac objects selected from the RGB sample. To investigate the intrinsic radiation property of BL Lac objects, we estimated the Doppler factor with the VLA or MERLIN core and the total 408 MHz luminosity for a sample of 170 BL Lac objects. The intrinsic (comoving) synchrotron peak frequency was then calculated by using the estimated Doppler factor. Assuming a Lorentz factor of 5, the viewing angle of jets was constrained. The high-resolution VLBI images of seven sources all show a core-jet structure. We estimated the proper motions of three sources with the VLBI archive data, and find that the apparent speed increases with the distance of components to the core for all of them. In our BL Lacs sample, the Doppler factor of LBLs is systematically larger than that of IBLs and HBLs. We find a significant anti-correlation between the total 408 MHz luminosity and the intrinsic synchrotron peak frequency. However, the scatter is much larger than for the blazar sequence. Moreover, we find a significant positive correlation between the viewing angle and the intrinsic synchrotron peak frequency. The BL Lac objects show a continuous distribution on the viewing angle. While LBLs have a smaller viewing angle than that of IBLs and HBLs, IBLs are comparable to HBLs. We conclude that the intrinsic synchrotron peak frequency is not only related to the intrinsic radio power (though with a large scatter), but also to the viewing angle for the present sample.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 16:57:37 GMT" } ]
2009-11-13T00:00:00
[ [ "Wu", "Zhongzu", "" ], [ "Jiang", "D. R.", "" ], [ "Gu", "Minfeng", "" ], [ "Liu", "Yi", "" ] ]
0706.0192
Nicolai Krylov
N.V. Krylov
On factorizations of smooth nonnegative matrix-values functions and on smooth functions with values in polyhedra
19 pages
null
null
null
math.OC math.AP
null
We discuss the possibility to represent smooth nonnegative matrix-valued functions as finite linear combinations of fixed matrices with positive real-valued coefficients whose square roots are Lipschitz continuous. This issue is reduced to a similar problem for smooth functions with values in a polyhedron.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 17:13:07 GMT" } ]
2007-06-04T00:00:00
[ [ "Krylov", "N. V.", "" ] ]
0706.0193
Joachim Moortgat
Joachim Moortgat, Eric G. Blackman, Chuang Ren, Xianglong Kong, Rui Yan
Particle-in-cell simulations of fast collisionless reconnection in gamma-ray burst outflows
4 pages 2 figures. Proceedings of the final open meeting of the RTN `GRBs, and enigma and tool': "070228 - The Next Decade of GRB afterglows"
null
null
null
astro-ph
null
We present preliminary results of particle-in-cell simulations of collisionless magnetic reconnection for conditions that apply to magnetically dominated pair plasma jets such as those in gamma-ray bursts. We find similar behaviour to previous authors but with reduced reconnection efficiency. This results because we include the full electromagnetic field dynamically and allow electric field fluctuations to grow. Although weak, these fluctuations impede early x-point formation by periodically decelerating and even reversing the inflow.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 17:59:04 GMT" } ]
2007-06-04T00:00:00
[ [ "Moortgat", "Joachim", "" ], [ "Blackman", "Eric G.", "" ], [ "Ren", "Chuang", "" ], [ "Kong", "Xianglong", "" ], [ "Yan", "Rui", "" ] ]
0706.0194
Andrea Sboner
Long J. Lu, Andrea Sboner, Yuanpeng J. Huang, Hao Xin Lu, Tara A. Gianoulis, Kevin Y. Yip, Philip M. Kim, and Gaetano T. Montelione, Mark B. Gerstein
Comparing Classical Pathways and Modern Networks: Towards the Development of an Edge Ontology
30 pages including 5 figures and supplemental material
null
null
null
q-bio.MN
null
Pathways are integral to systems biology. Their classical representation has proven useful but is inconsistent in the meaning assigned to each arrow (or edge) and inadvertently implies the isolation of one pathway from another. Conversely, modern high-throughput experiments give rise to standardized networks facilitating topological calculations. Combining these perspectives, we can embed classical pathways within large-scale networks and thus demonstrate the crosstalk between them. As more diverse types of high-throughput data become available, we can effectively merge both perspectives, embedding pathways simultaneously in multiple networks. However, the original problem still remains - the current edge representation is inadequate to accurately convey all the information in pathways. Therefore, we suggest that a standardized, well-defined, edge ontology is necessary and propose a prototype here, as a starting point for reaching this goal.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 18:12:11 GMT" } ]
2007-06-04T00:00:00
[ [ "Lu", "Long J.", "" ], [ "Sboner", "Andrea", "" ], [ "Huang", "Yuanpeng J.", "" ], [ "Lu", "Hao Xin", "" ], [ "Gianoulis", "Tara A.", "" ], [ "Yip", "Kevin Y.", "" ], [ "Kim", "Philip M.", "" ], [ "Montelione", "Gaetano T.", "" ], [ "Gerstein", "Mark B.", "" ] ]
0706.0195
Erkko Lehtonen
Erkko Lehtonen, Agnes Szendrei
Equivalence of operations with respect to discriminator clones
17 pages
Discrete Math. 309 (2009) 673-685
10.1016/j.disc.2008.01.003
null
math.RA
null
For each clone C on a set A there is an associated equivalence relation, called C-equivalence, on the set of all operations on A, which relates two operations iff each one is a substitution instance of the other using operations from C. In this paper we prove that if C is a discriminator clone on a finite set, then there are only finitely many C-equivalence classes. Moreover, we show that the smallest discriminator clone is minimal with respect to this finiteness property. For discriminator clones of Boolean functions we explicitly describe the associated equivalence relations.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 18:29:57 GMT" } ]
2016-11-22T00:00:00
[ [ "Lehtonen", "Erkko", "" ], [ "Szendrei", "Agnes", "" ] ]
0706.0196
Maikel Rheinstadter
Arne Schafer, Tim Salditt, and Maikel C. Rheinstadter
Atomic force microscopy (AFM) study of thick lamellar stacks of phospholipid bilayers
null
Phys. Rev. E 77, 021905 (2008) (8 pages).
10.1103/PhysRevE.77.021905
null
physics.bio-ph
null
We report an Atomic Force Microscopy (AFM) study on thick multi lamellar stacks of approx. 10 mum thickness (about 1500 stacked membranes) of DMPC (1,2-dimyristoyl-sn-glycero-3-phoshatidylcholine) deposited on silicon wafers. These thick stacks could be stabilized for measurements under excess water or solution. From force curves we determine the compressional modulus B and the rupture force F_r of the bilayers in the gel (ripple), the fluid phase and in the range of critical swelling close to the main transition. AFM allows to measure the compressional modulus of stacked membrane systems and values for B compare well to values reported in the literature. We observe pronounced ripples on the top layer in the Pbeta' (ripple) phase and find an increasing ripple period Lambda_r when approaching the temperature of the main phase transition into the fluid Lalpha phase at about 24 C. Metastable ripples with 2Lambda_r are observed. Lambda_r also increases with increasing osmotic pressure, i.e., for different concentrations of polyethylene glycol (PEG).
[ { "version": "v1", "created": "Fri, 1 Jun 2007 18:38:44 GMT" } ]
2009-10-02T00:00:00
[ [ "Schafer", "Arne", "" ], [ "Salditt", "Tim", "" ], [ "Rheinstadter", "Maikel C.", "" ] ]
0706.0197
Masahito Hayashi
Masahito Hayashi
Prior entanglement between senders enables perfect quantum network coding with modification
5 pages, 5 figures
Phys. Rev. A, 76, 040301(R) (2007)
10.1103/PhysRevA.76.040301
null
quant-ph
null
We find a protocol transmitting two quantum states crossly in the butterfly network only with prior entanglement between two senders. This protocol requires only one qubit transmission or two classical bits transmission in each channel in the butterfly network. It is also proved that it is impossible without prior entanglement. More precisely, an upper bound of average fidelity is given in the butterfly network when prior entanglement is not allowed.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 18:36:00 GMT" }, { "version": "v2", "created": "Thu, 7 Jun 2007 16:13:30 GMT" } ]
2009-11-13T00:00:00
[ [ "Hayashi", "Masahito", "" ] ]
0706.0198
Na Sai
Na Sai, Michael Zwolak, Giovanni Vignale, and Massimiliano Di Ventra
Reply to Comment on "Dynamical corrections to the DFT-LDA electron conductance in nanoscale systems"
Reply to the comment by Jung et al (arXiv:0706.0140). 1 page, no figures, to appear in PRL
Phys. Rev. Lett. 98, 259702 (2007)
10.1103/PhysRevLett.98.259702
null
cond-mat.mes-hall cond-mat.mtrl-sci
null
We reply to the comment by Jung, Bokes, and Godby (arXiv:0706.0140) on our paper Phys. Rev. Lett. 94, 186810 (2005). We show that the results in their comment should not be taken as an indication that the viscosity corrections to the conductance of real nanoscale structures are small. A more accurate treatment of the density and current density distribution and of the electronic correlations may yield much larger corrections in realistic systems.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:49:27 GMT" } ]
2007-06-19T00:00:00
[ [ "Sai", "Na", "" ], [ "Zwolak", "Michael", "" ], [ "Vignale", "Giovanni", "" ], [ "Di Ventra", "Massimiliano", "" ] ]
0706.0199
Gregory B. Cook
Gregory B. Cook and Bernard F. Whiting
Approximate Killing Vectors on S^2
4 pages, 3 figures, submitted to Physical Review D, revtex4
Phys.Rev.D76:041501,2007
10.1103/PhysRevD.76.041501
null
gr-qc
null
We present a new method for computing the best approximation to a Killing vector on closed 2-surfaces that are topologically S^2. When solutions of Killing's equation do not exist, this method is shown to yield results superior to those produced by existing methods. In addition, this method appears to provide a new tool for studying the horizon geometry of distorted black holes.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:01:14 GMT" } ]
2008-11-26T00:00:00
[ [ "Cook", "Gregory B.", "" ], [ "Whiting", "Bernard F.", "" ] ]
0706.0200
Marc-Thomas Eisele
Marc-Thomas Eisele
Leptogenesis With Many Neutrinos
matches published version, 38 pages, 10 figures
Phys.Rev.D77:043510,2008
10.1103/PhysRevD.77.043510
null
hep-ph
null
We consider leptogenesis in scenarios with many neutrino singlets. We find that the lower bound for the reheating temperature can be significantly relaxed with respect to the hierarchical three neutrino case. We further argue that the upper bound for the neutrino mass scale from leptogenesis gets significantly lifted in these scenarios. As a specific realization, we then discuss an extra-dimensional model, where the large number of neutrinos is provided by Kaluza-Klein excitations.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:30:50 GMT" }, { "version": "v2", "created": "Wed, 27 Jun 2007 15:46:10 GMT" }, { "version": "v3", "created": "Tue, 12 Feb 2008 16:27:39 GMT" } ]
2008-11-26T00:00:00
[ [ "Eisele", "Marc-Thomas", "" ] ]
0706.0201
Mark Walker
Greg Piepmeyer, Mark E. Walker
A New Proof of the New Intersection Theorem
null
null
null
null
math.AC math.KT
null
In 1987 Roberts completed the proof of the New Intersection Theorem (NIT) by settling the mixed characteristic case using local Chern characters, as developed by Fulton and also by Roberts. His proof has been the only one recorded of the NIT in mixed characteristic. This paper gives a new proof of this theorem, one which mostly parallels Roberts' original proof, but avoids the use of local Chern characters. Instead, the proof here uses Adams operations on K-theory with supports as developed by Gillet-Soule.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:17:43 GMT" } ]
2007-06-04T00:00:00
[ [ "Piepmeyer", "Greg", "" ], [ "Walker", "Mark E.", "" ] ]
0706.0202
Denis Feyel
Denis Feyel, Arnaud De La Pradelle (IMJ), Gabriel Mokobodzki (IMJ)
A non commutative sewing lemma
11 pages
null
null
null
math.PR
null
In a preceding paper [E.J.ofProb.34,860-892,(2006)], we proved a sewing lemma which was a key result for the study of Holder continuous functions. In this paper we give a non-commutative version of this lemma with some applications.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:31:54 GMT" } ]
2007-06-04T00:00:00
[ [ "Feyel", "Denis", "", "IMJ" ], [ "De La Pradelle", "Arnaud", "", "IMJ" ], [ "Mokobodzki", "Gabriel", "", "IMJ" ] ]
0706.0203
Leandro Aolita
Leandro Aolita, Luiz Davidovich, Kihwan Kim, and Hartmut H\"affner
Universal quantum computation in decoherence-free subspaces with hot trapped-ions
8 pages, 1 figure
Phys. Rev. A 75, 052337 (2007)
10.1103/PhysRevA.75.052337
null
quant-ph
null
We consider interactions that generate a universal set of quantum gates on logical qubits encoded in a collective-dephasing-free subspace, and discuss their implementations with trapped ions. This allows for the removal of the by-far largest source of decoherence in current trapped-ion experiments, collective dephasing. In addition, an explicit parametrization of all two-body Hamiltonians able to generate such gates without the system's state ever exiting the protected subspace is provided.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:32:16 GMT" } ]
2016-08-14T00:00:00
[ [ "Aolita", "Leandro", "" ], [ "Davidovich", "Luiz", "" ], [ "Kim", "Kihwan", "" ], [ "Häffner", "Hartmut", "" ] ]
0706.0204
Jean-Francois Delmas
Jean-Fran\c{c}ois Delmas (CERMICS), Jean-St\'ephane Dhersin (MAP5), Arno Siri-Jegousse (MAP5)
Asymptotic results on the length of coalescent trees
null
null
null
null
math.PR
null
We give the asymptotic distribution of the length of partial coalescent trees for Beta and related coalescents. This allows us to give the asymptotic distribution of the number of (neutral) mutations in the partial tree. This is a first step to study the asymptotic distribution of a natural estimator of DNA mutation rate for species with large families.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:32:31 GMT" } ]
2007-06-04T00:00:00
[ [ "Delmas", "Jean-François", "", "CERMICS" ], [ "Dhersin", "Jean-Stéphane", "", "MAP5" ], [ "Siri-Jegousse", "Arno", "", "MAP5" ] ]
0706.0205
David Coule
D. H. Coule
On initial conditions for inflationary and bouncing cosmologies
28pages, updated
null
null
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the question of deriving initial conditions for scalar fields in driving both an early and late quintessence phase. The dark energy field presents an unresolved uniformity problem. Further difficulties with initial conditions for assisted, kinetic and phantom inflation are presented. We review the use of the canonical measure and find the negative conclusions of Gibbons and Hawking can be allayed by means of a reasonable quantum cosmological input. We remark upon some attempts at incorporating inflationary schemes into cyclic and bouncing models.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 19:34:26 GMT" }, { "version": "v2", "created": "Wed, 20 Jun 2007 18:50:50 GMT" }, { "version": "v3", "created": "Wed, 27 Jun 2007 17:38:27 GMT" }, { "version": "v4", "created": "Thu, 20 Sep 2007 15:31:52 GMT" }, { "version": "v5", "created": "Thu, 31 Jan 2008 20:07:42 GMT" }, { "version": "v6", "created": "Wed, 19 Dec 2012 18:28:22 GMT" } ]
2012-12-20T00:00:00
[ [ "Coule", "D. H.", "" ] ]
0706.0206
David M. Bradley
David M. Bradley, Ali E. Ozluk and C. Snyder
On a class number formula for real quadratic number fields
12 pages AMSLaTeX
Bulletin of the Australian Mathematical Society Vol. 65 (2002), no. 2, pp. 259--270. [MR 1898540] (2003a:11112)
null
null
math.NT
null
For an even Dirichlet character psi, we obtain a formula for L(1,psi) in terms of a sum of Dirichlet L-series evaluated at s=2 and s=3 and a rapidly convergent numerical series involving the central binomial coefficients. We then derive a class number formula for real quadratic number fields by taking L(s,psi) to be the quadratic L-series associated with these fields.
[ { "version": "v1", "created": "Sun, 3 Jun 2007 23:38:05 GMT" } ]
2007-06-05T00:00:00
[ [ "Bradley", "David M.", "" ], [ "Ozluk", "Ali E.", "" ], [ "Snyder", "C.", "" ] ]
0706.0207
Philip D. Mannheim
Carl M. Bender and Philip D. Mannheim
No-ghost theorem for the fourth-order derivative Pais-Uhlenbeck oscillator model
revtex4, 4 pages
Phys.Rev.Lett.100:110402,2008
10.1103/PhysRevLett.100.110402
preprint LA-UR-07-3525
hep-th gr-qc quant-ph
null
Contrary to common belief, it is shown that theories whose field equations are higher than second order in derivatives need not be stricken with ghosts. In particular, the prototypical fourth-order derivative Pais-Uhlenbeck oscillator model is shown to be free of states of negative energy or negative norm. When correctly formulated (as a $\cP\cT$ symmetric theory), the theory determines its own Hilbert space and associated positive-definite inner product. In this Hilbert space the model is found to be a fully acceptable quantum-mechanical theory that exhibits unitary time evolution.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 20:46:24 GMT" } ]
2008-11-26T00:00:00
[ [ "Bender", "Carl M.", "" ], [ "Mannheim", "Philip D.", "" ] ]
0706.0208
Martin White
J.D. Cohn, Martin White
Dark matter halo abundances, clustering and assembly histories at high redshift
9 pages, 9 figures, resubmitted to MNRAS, added some references and convergence tests to better constrain bias
null
10.1111/j.1365-2966.2008.12972.x
null
astro-ph
null
We use a suite of high-resolution N-body simulations to study the properties, abundance and clustering of high mass halos at high redshift, including their mass assembly histories and mergers. We find that the analytic form which best fits the abundance of halos depends sensitively on the assumed definition of halo mass, with common definitions of halo mass differing by a factor of two for these low concentration, massive halos. A significant number of massive halos are undergoing rapid mass accretion, with major merger activity being common. We compare the mergers and mass accretion histories to the extended Press-Schechter formalism. We consider how major merger induced star formation or black hole accretion may change the distribution of photon production from collapsed halos, and hence reionization, using some simplified examples. In all of these, the photon distribution for a halo of a given mass acquires a large scatter. If rare, high mass halos contribute significantly to the photon production rates, the scatter in photon production rate can translate into additional scatter in the sizes of ionized bubbles.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 20:00:05 GMT" }, { "version": "v2", "created": "Fri, 4 Jan 2008 20:47:44 GMT" } ]
2009-11-13T00:00:00
[ [ "Cohn", "J. D.", "" ], [ "White", "Martin", "" ] ]
0706.0209
Jason Eastman
Jason Eastman, Paul Martini, Gregory Sivakoff (Ohio State), Daniel D. Kelson, John S. Mulchaey (Carnegie Observatories), and Kim-Vy Tran (University of Zurich and Leiden Observatory)
First Measurement of a Rapid Increase in the AGN Fraction in High-Redshift Clusters of Galaxies
ApJL Accepted, 5 pages, 2 figures
null
10.1086/520577
null
astro-ph
null
We present the first measurement of the AGN fraction in high-redshift clusters of galaxies (z~0.6) with spectroscopy of one cluster and archival data for three additional clusters. We identify 8 AGN in all four of these clusters from the Chandra data, which are sensitive to AGN with hard X-ray (2-10keV) luminosity L_{X,H} > 10^43 erg/s in host galaxies more luminous than a rest frame M_R < -20 mag. This stands in sharp contrast to the one AGN with L_{X,H} > 10^43 erg/s we discovered in our earlier study of eight low-redshift clusters with z=0.06-0.31 (average z~0.2). Three of the four high-redshift cluster datasets are sensitive to nearly L_{X,H} > 10^42 erg/s and we identify seven AGN above this luminosity limit, compared to two in eight, low-redshift clusters. Based on membership estimates for each cluster, we determine that the AGN fraction at z~0.6 is f_A(L_X>10^42;M_R<-20) = 0.028 (+0.019/-0.012) and f_A(L_X>10^43;M_R<-20) = 0.020 (+0.012/-0.008). These values are approximately a factor of 20 greater than the AGN fractions in lower-redshift (average z~0.2) clusters of galaxies and represent a substantial increase over the factors of 1.5 and 3.3 increase, respectively, in the measured space density evolution of the hard X-ray luminosity function over this redshift range. Potential systematic errors would only increase the significance of our result. The cluster AGN fraction increases more rapidly with redshift than the field and the increase in cluster AGN indicates the presence of an AGN Butcher-Oemler Effect.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 20:00:28 GMT" }, { "version": "v2", "created": "Wed, 6 Jun 2007 10:10:19 GMT" } ]
2009-11-13T00:00:00
[ [ "Eastman", "Jason", "", "Ohio State" ], [ "Martini", "Paul", "", "Ohio State" ], [ "Sivakoff", "Gregory", "", "Ohio State" ], [ "Kelson", "Daniel D.", "", "Carnegie Observatories" ], [ "Mulchaey", "John S.", "", "Carnegie Observatories" ], [ "Tran", "Kim-Vy", "", "University of Zurich and Leiden Observatory" ] ]
0706.0210
Tobias Kaufmann
Tobias Kaufmann, Coral Wheeler and James S. Bullock (University of California, Irvine)
On the morphologies, gas fractions, and star formation rates of small galaxies
10 pages, 8 figures, MNRAS in press. Minor changes in response to referee comments
Mon.Not.Roy.Astron.Soc.382:1187-1195,2007
10.1111/j.1365-2966.2007.12436.x
null
astro-ph
null
We use a series of N-body/smoothed particle hydrodynamics simulations and analytic arguments to show that the presence of an effective temperature floor in the interstellar medium at T_F ~ 10^4 K naturally explains the tendency for low-mass galaxies to be more spheroidal, more gas rich, and less efficient in converting baryons into stars than larger galaxies. The trend arises because gas pressure support becomes important compared to angular momentum support in small dark matter haloes. We suggest that dwarf galaxies with rotational velocities ~ 40 km/s do not originate as thin discs, but rather are born as thick, puffy systems. If accreted on to larger haloes, tenuous dwarfs of this kind will be more susceptible to gas loss or tidal transformation than scaled-down versions of larger spirals. For a constant temperature floor, pressure support becomes less important in large haloes, and this produces a tendency for massive isolated galaxies to have thinner discs and more efficient star formation than their less massive counterparts, as observed.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 21:06:34 GMT" }, { "version": "v2", "created": "Fri, 12 Oct 2007 23:47:32 GMT" } ]
2009-11-16T00:00:00
[ [ "Kaufmann", "Tobias", "", "University of\n California, Irvine" ], [ "Wheeler", "Coral", "", "University of\n California, Irvine" ], [ "Bullock", "James S.", "", "University of\n California, Irvine" ] ]
0706.0211
Joanne D. Cohn
J.D. Cohn, A.E. Evrard, M. White, D. Croton, E. Ellingson
Red Sequence Cluster Finding in the Millennium Simulation
final version to appear in MNRAS. Appendix added on purity and completeness, small shift in red sequence due to correcting an error in finding it
null
10.1111/j.1365-2966.2007.12479.x
null
astro-ph
null
We investigate halo mass selection properties of red-sequence cluster finders using galaxy populations of the Millennium Simulation (MS). A clear red sequence exists for MS galaxies in massive halos at redshifts z < 1, and we use this knowledge to inform a cluster-finding algorithm applied to 500 Mpc/h projections of the simulated volume. At low redshift (z=0.4), we find that 90% of the clusters found have galaxy membership dominated by a single, real-space halo, and that 10% are blended systems for which no single halo contributes a majority of a cluster's membership. At z=1, the fraction of blends increases to 22%, as weaker redshift evolution in observed color extends the comoving length probed by a fixed range of color. Other factors contributing to the increased blending at high-z include broadening of the red sequence and confusion from a larger number of intermediate mass halos hosting bright red galaxies of magnitude similar to those in higher mass halos. Our method produces catalogs of cluster candidates whose halo mass selection function, p(M|\Ngal,z), is characterized by a bimodal log-normal model with a dominant component that reproduces well the real-space distribution, and a redshift-dependent tail that is broader and displaced by a factor ~2 lower in mass. We discuss implications for X-ray properties of optically selected clusters and offer ideas for improving both mock catalogs and cluster-finding in future surveys.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 20:04:45 GMT" }, { "version": "v2", "created": "Mon, 17 Sep 2007 14:21:06 GMT" } ]
2009-11-13T00:00:00
[ [ "Cohn", "J. D.", "" ], [ "Evrard", "A. E.", "" ], [ "White", "M.", "" ], [ "Croton", "D.", "" ], [ "Ellingson", "E.", "" ] ]
0706.0212
Anatoli Polkovnikov
Anatoli Polkovnikov and Vladimir Gritsev
Breakdown of the adiabatic limit in low dimensional gapless systems
11 pages, 5 figures, to appear in Nature Physics (originally submitted version)
NaturePhys.4:477,2008
10.1038/nphys963
null
cond-mat.stat-mech cond-mat.dis-nn hep-th quant-ph
null
It is generally believed that a generic system can be reversibly transformed from one state into another by sufficiently slow change of parameters. A standard argument favoring this assertion is based on a possibility to expand the energy or the entropy of the system into the Taylor series in the ramp speed. Here we show that this argumentation is only valid in high enough dimensions and can break down in low-dimensional gapless systems. We identify three generic regimes of a system response to a slow ramp: (A) mean-field, (B) non-analytic, and (C) non-adiabatic. In the last regime the limits of the ramp speed going to zero and the system size going to infinity do not commute and the adiabatic process does not exist in the thermodynamic limit. We support our results by numerical simulations. Our findings can be relevant to condensed-matter, atomic physics, quantum computing, quantum optics, cosmology and others.
[ { "version": "v1", "created": "Fri, 1 Jun 2007 20:06:17 GMT" }, { "version": "v2", "created": "Thu, 17 Jan 2008 21:50:55 GMT" } ]
2008-11-26T00:00:00
[ [ "Polkovnikov", "Anatoli", "" ], [ "Gritsev", "Vladimir", "" ] ]
0706.0213
Steven Gubser
Steven S. Gubser, Silviu S. Pufu, and Amos Yarom
Energy disturbances due to a moving quark from gauge-string duality
23 pages, 5 figures
JHEP 0709:108,2007
10.1088/1126-6708/2007/09/108
PUPT-2236, LMU-ASC 34/07
hep-th
null
Using AdS/CFT, we calculate the energy density of a quark moving through a thermal state of N=4 super-Yang-Mills theory. Relying on previous work for momentum-space representations as well as asymptotic behaviors, we Fourier transform to position space and exhibit a sonic boom at a speed larger than the speed of sound. Nontrivial structure is found at small length scales, confirming earlier analytical work by the authors.
[ { "version": "v1", "created": "Mon, 4 Jun 2007 14:21:31 GMT" } ]
2009-04-17T00:00:00
[ [ "Gubser", "Steven S.", "" ], [ "Pufu", "Silviu S.", "" ], [ "Yarom", "Amos", "" ] ]