December 2007 arXiv papers — page 25

Nikolay M. Nikolov

A cohomological analysis of the renormalization freedom is performed in the Epstein-Glaser scheme on a flat Euclidean space. We study the deviation from commutativity between the renormalization and the action of all linear partial differential operators. It defines a Hochschild 1-cocycle and the renormalization ambiguity corresponds to a nonlinear subset in

E. N. Saridakis

We present a generalized version of holographic dark energy arguing that it must be considered in the maximally subspace of a cosmological model. In the context of brane cosmology it leads to a bulk holographic dark energy which transfers its holographic nature to the effective 4D dark energy. As an application we use a single-brane model and we show that in

J. Sabio, C. Seoanez, S. Fratini, F. Guinea

We analyze the electrostatic interactions between a single graphene layer and a SiO$_2$ susbtrate, and other materials which may exist in its environment. We obtain that the leading effects arise from the polar modes at the SiO$_2$ surface, and water molecules, which may form layers between the graphene sheet and the substrate. The strength of the interactio

Simon Scott

We show that there is a canonical construction of a zeta (Bismut-Quillen) connection on the determinant line bundle of a family of APS elliptic boundary problems and that it has curvature equal to the 2-form part of a relative eta form.

Alireza Akbari

At very low temperatures, the tunnelling theory for amorphous solids predicts a thermal conductivity $κ\propto T^p$, with $p = 2$. We have studied the effect of the Nuclear Quadrupole moment on the thermal conductivity of glasses at very low temperatures. We developed a theory that couples the tunnelling motion to the nuclear quadrupoles moment in order to e

James P. Bagrow, Jie Sun, Daniel ben-Avraham

The rich-get-richer mechanism (agents increase their ``wealth'' randomly at a rate proportional to their holdings) is often invoked to explain the Pareto power-law distribution observed in many physical situations, such as the degree distribution of growing scale free nets. We use two different analytical approaches, as well as numerical simulations,

L. Cywinski, R. M. Lutchyn, C. P. Nave, S. Das Sarma

We theoretically investigate the influence of designed pulse sequences in restoring quantum coherence lost due to background noise in superconducting qubits. We consider both 1/f noise and Random Telegraph Noise, and show that the qubit coherence time can be substantially enhanced by carefully engineered pulse sequences. Conversely, the time dependence of qu

I. R. Klebanov, A. Murugan, D. Rodriguez-Gomez, J. Ward

A warped resolved conifold background of type IIB theory, constructed in hep-th/0701064, is dual to the supersymmetric $SU(N)\times SU(N)$ gauge theory with a vacuum expectation value (VEV) for one of the bifundamental chiral superfields. This VEV breaks both the superconformal invariance and the baryonic symmetry. The absolute value of the VEV controls the

Ondrej Pejcha, David Heyrovsky

We explore the sensitivity of two-point-mass gravitational microlensing to the extended nature of the source star, as well as the related sensitivity to its limb darkening. We demonstrate that the sensitive region, usually considered to be limited to a source-diameter-wide band along the caustic, is strongly expanded near cusps, most prominently along their

Mark M. Wilde, Todd A. Brun

We show how to protect a stream of quantum information from decoherence induced by a noisy quantum communication channel. We exploit preshared entanglement and a convolutional coding structure to develop a theory of entanglement-assisted quantum convolutional coding. Our construction produces a Calderbank-Shor-Steane (CSS) entanglement-assisted quantum convo

Philipp Gegenwart, Qimiao Si, Frank Steglich

Quantum criticality describes the collective fluctuations of matter undergoing a second-order phase transition at zero temperature. Heavy fermion metals have in recent years emerged as prototypical systems to study quantum critical points. There have been considerable efforts, both experimental and theoretical, which use these magnetic systems to address pro

Auguste Aman

In this paper we study the class of backward doubly stochastic differential equations (BDSDEs, for short) whose terminal value depends on the history of forward diffusion. We first establish a probabilistic representation for the spatial gradient of the stochastic viscosity solution to a quasilinear parabolic SPDE in the spirit of the Feynman-Kac formula, wi

Tullia Dymarz

In this paper we provide the final steps in the proof, announced by Eskin-Fisher-Whyte, of quasi-isometric rigidity of a class of non-nilpotent polycyclic groups. To this end, we prove a rigidity theorem on the boundaries of certain negatively curved homogeneous spaces and combine it with work of Eskin-Fisher-Whyte and Peng on the structure of quasi-isometri

H. Komaie-Moghaddam, M. Khorrami, A. H. Fatollahi

The structure of loop corrections is examined in a scalar field theory on a three dimensional space whose spatial coordinates are noncommutative and satisfy SU(2) Lie algebra. In particular, the 2- and 4-point functions in $ϕ^4$ scalar theory are calculated at the 1-loop order. The theory is UV-finite as the momentum space is compact. It is shown that the no

Redamy Perez Ramos, Francois Arleo, Bruno Machet

The hadronic kt-spectrum inside a high energy jet is determined including corrections of relative magnitude O{\sqrt{α_s}} with respect to the Modified Leading Logarithmic Approximation (MLLA), in the limiting spectrum approximation (assuming an infrared cut-off Q0 =Lambda_{QCD}) and beyond Q_0\neΛ_{QCD}. The results in the limiting spectrum approximation are

Julien Grivaux

In this article, we construct Chern classes in rational Deligne cohomology for coherent sheaves on a smooth complex compact manifold. We prove that these classes verify the functoriality property under pullbacks, the Whitney formula and the Grothendieck-Riemann-Roch theorem for projective morphisms between smooth complex compact manifolds.

Emidio Gabrielli

We consider a U(1) gauge theory, minimally coupled to a massless Dirac field, where a higher-derivative term is added to the pure gauge sector, as in the Lee-Wick models. We find that this term can trigger chiral symmetry breaking at low energy in the weak coupling regime. Then, the fermion field acquires a mass that turns out to be a function of both the en

Hiroshi Iritani

We study real and integral structures in the space of solutions to the quantum differential equations. First we show that, under mild conditions, any real structure in orbifold quantum cohomology yields a pure and polarized tt^*-geometry near the large radius limit. Secondly, we use mirror symmetry to calculate the "most natural" integral structure i

Christian Korff

We present in detail a recent conjecture on self-adjoint representations of the Temperley-Lieb algebra for particular values on the unit circle. The formulation in terms of graphical calculus is emphasized and discussed for several examples. The role of PT (parity and time reversal) invariance is highlighted as it might prove important for generalising the c

Sergei Winitzki

The picture of the "multiverse" arising in diverse cosmological scenarios involves transitions between metastable vacuum states. It was pointed out by Krauss and Dent that the transition rates decrease at very late times, leading to a dependence of the transition probability between vacua on the age of each vacuum region. I investigate the implicatio

Uri Jacob, Tsvi Piran

We point out that previous studies of possible Lorentz-violating effects in astronomical time-of-flight data did not take into account the entire implications of the universe's cosmological expansion. We present the derivation of the accurate formulation of the problem and show that the resulting correction of the limits on Lorentz violation is significa

Yu. A. Simonov

The di-pion spectrum for the $Υ(nS) \to Υ(n&#39;S))$ transition with $n\leq 4$ has the form $\frac{dw}{dq}\sim $ (phase space) $ |η-x|^2$, with $x=\frac{q^2-4m^2_π}{(ΔM)^2 -4 m^2_π}< q^2 \equiv M^2_{ππ}, $ and $ΔM=M(nS) -M(n&#39;S)$. The parameter $η$ is calculated and the spectrum is shown to reproduce the experimental data for all 3 types of decays: $3\to

Robert H. Brandenberger, Andrew R. Frey, Larissa C. Lorenz

We study the development of entropy fluctuations in brane inflation in a warped throat, including the brane-antibrane tachyon as the waterfall field. We find that there is a period at the end of inflation during which the entropy mode associated with the tachyon field increases exponentially. In turn, the induced entropy seeds a contribution to the curvature

D. A. Kann, S. Klose, B. Zhang, D. Malesani

We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to September 2009, for a total of 76 GRBs, and present an additional three pre-Swift GRBs not included in an earlier sample. Furthermore, we publish 840 additional new photometry data points on a total of 42 GRB after

J. Chang, Ch. Niedermayer, R. Gilardi, N. B. Christensen

We report the results of a combined muon spin rotation and neutron scattering study on La2-xSrxCuO4 in the vicinity of the so-called 1/8-anomaly. Application of a magnetic field drives the system towards a magnetically ordered spin-density-wave state, which is fully developed at 1/8 doping. The results are discussed in terms of competition between antiferrom

Bernd Jenichen, Vladimir Kaganer, Wolfgang Braun, Roman Shayduk

Molecular beam epitaxy of Fe3Si on GaAs(001) is studied in situ by grazing incidence x-ray diffraction. Layer-by-layer growth of Fe3Si films is observed at a low growth rate and substrate temperatures near 200 degrees Celsius. A damping of x-ray intensity oscillations due to a gradual surface roughening during growth is found. The corresponding sequence of c

Andrea Ferrantelli

The WW scattering into gravitino and gaugino is here investigated in the broken phase, by using both gauge and mass eigenstates. Differently from what is obtained for unbroken gauge symmetry, we find in the scattering amplitudes new structures, which can lead to violation of unitarity above a certain scale. This happens because, in the annihilation diagram,

Matthew Morrow

We consider non-linear changes of variables and Fubini's theorem for certain integrals over a two-dimensional local field. An interesting example is presented in which imperfectness of a finite characteristic local field causes Fubini's theorem to unexpectedly fail. The relationship to ramification theory is discussed.

Harry K. Hahn, Kay Schoenberger

Natural numbers divisible by the same prime factor lie on defined spiral graphs which are running through the Square Root Spiral (also named as the Spiral of Theodorus or Wurzel Spirale or Einstein Spiral). Prime Numbers also clearly accumulate on such spiral graphs. And the square numbers 4, 9, 16, 25, 36,... form a highly three-symmetrical system of three

P. -A. Söderström

The basic principles of detection of fast neutrons with liquid scintillator detectors are reviewed, together with a real example in the form of the Neutron Wall array. Two of the challenges in neutron detection, discrimination of neutrons and gamma rays and identification of cross talk between detectors due to neutron scattering, are briefly discussed, as we

G. Delfino, G. Niccoli

For the simplest quantum field theory originating from a non-trivial fixed point of the renormalization group, the Lee-Yang model, we show that the operator space determined by the particle dynamics in the massive phase and that prescribed by conformal symmetry at criticality coincide.

James Alsup, George Siopsis

We consider a large black hole in asymptotically AdS spacetime of arbitrary dimension with a Minkowski boundary. By performing an appropriate slicing as we approach the boundary, we obtain via holographic renormalization a gauge theory fluid obeying Bjorken hydrodynamics in the limit of large longitudinal proper time. The metric we obtain reproduces to leadi

Giuseppe Falzetta, Francesco Longo, Alba Zanini

CREME96 and GEANT4 are two well known particle transport codes through matter in space science. We present a comparison between the proton fluxes outgoing from an aluminium target, obtained by using both tools. The primary proton flux is obtained by CREME96 only, covering an energy range from MeV to hundreds GeV with the same result in both cases. We studied

Tsuyoshi Ito, Hirotada Kobayashi, Daniel Preda, Xiaoming Sun

A central question in quantum information theory and computational complexity is how powerful nonlocal strategies are in cooperative games with imperfect information, such as multi-prover interactive proof systems. This paper develops a new method for proving limits of nonlocal strategies that make use of prior entanglement among players (or, provers, in the

J. Bouttier, E. Guitter

We study the statistical properties of geodesics, i.e. paths of minimal length, in large random planar quadrangulations. We extend Schaeffer&#39;s well-labeled tree bijection to the case of quadrangulations with a marked geodesic, leading to the notion of &#34;spine trees&#34;, amenable to a direct enumeration. We obtain the generating functions for quadrang

F. de Campos, O. J. P. Eboli, M. B. Magro, W. Porod

We study the collider phenomenology of bilinear R-parity violating supergravity, the simplest effective model for supersymmetric neutrino masses accounting for the current neutrino oscillation data. At the CERN Large Hadron Collider the center-of-mass energy will be high enough to probe directly these models through the search for the superpartners of the St

B. Cuadros-Melgar, C. E. Pellicer

We consider scalar perturbations in the time-dependent Hourava-Witten Model in order to probe its stability. We show that during the non-singular epoque the model evolves without instabilities until it encounters the curvature singularity where a big crunch is supposed to occur. We compute the frequencies of the scalar field oscillation during the stable per

Seung-il Nam, Hyun-Chul Kim

We present in this talk a recent investigation on the magnetic susceptibility (chi) of the QCD vacuum at finite density, utilizing the nonlocal chiral quark model from the instanton vacuum. We take into account the nonzero current-quark mass (m_q) explicitly to consider the effect of explicit flavor SU(3) symmetry breaking. It turns out that, when we turn on

Seok-Chan Youn, Hyun-Woo Lee, H. -S. Sim

We study nonequilibrium dephasing in an electronic Mach-Zehnder interferometer. We demonstrate that the shot noise at the beam splitter of the interferometer generates an ensemble of nonequilibrium electron density configurations and that electron interactions induce configuration-specific phase shifts of an interfering electron. The resulting dephasing exhi

V. Gol&#39;dshtein, A. Ukhlov

We study global regularity properties of Sobolev homeomorphisms on $n$-dimensional Riemannian manifolds under the assumption of $p$-integrability of its first weak derivatives in degree $p\geq n-1$. We prove that inverse homeomorphisms have integrable first weak derivatives. For the case $p>n$ we obtain necessary conditions for existence of Sobolev homeomorp

A. Cano, E. I. Kats

The phenomenological theory of ferroelectricity in spiral magnets presented in [M. Mostovoy, Phys. Rev. Lett. 96, 067601 (2006)] is generalized to describe consistently states with both uniform and modulated-in-space ferroelectric polarizations. A key point in this description is the symmetric part of the magnetoelectric coupling since, although being irrele

Roberto Longo, Karl-Henning Rehren

The relation between two-dimensional conformal quantum field theories with and without a timelike boundary is explored.

N. Ghosh, H. Schmidt, M. Grundmann

Sub-gap conductance at a large area junction with a rough interface of a ferromagnet and a high-T$_{C}$ superconductor is superimposed by multiple peaks which is not expected from an ideal point contact Andreev reflection process. We demonstrate this phenomenon by measuring resistance as a function of bias voltage of a Co/Y$_{1}$Ba$_{2}$Cu$_{3}$O$_{7-δ}$ jun

Andreas Hackl, Matthias Vojta

The unconventional critical behavior near magnetic quantum phase transitions in various heavy-fermion metals, apparently inconsistent with the standard spin-density-wave scenario, has triggered proposals on the breakdown of the Kondo effect at the critical point. Here we investigate, within one specific scenario, the fate of such a zero-temperature transitio

Tom H. Koornwinder, Michael J. Schlosser

An identity by Chaundy and Bullard writes 1/(1-x)^n (n=1,2,...) as a sum of two truncated binomial series. This identity was rediscovered many times. Notably, a special case was rediscovered by I. Daubechies, while she was setting up the theory of wavelets of compact support. We discuss or survey many different proofs of the identity, and also its relationsh

Noriyuki Abe

We determine when there exists a nonzero homomorphism between principal series representations of a complex semisimple Lie group. We also determines the existence of homomorphisms between twisted Verma modules.

A. Baas, K. G. Lagoudakis, M. Richard, R. Andre

Condensation of exciton-polaritons in semiconductor microcavities takes place despite in plane disorder. Below the critical density the inhomogeneity of the potential seen by the polaritons strongly limits the spatial extension of the ground state. Above the critical density, in presence of weak disorder, this limitation is spontaneously overcome by the non

Mofazzal Azam, M. Sami, C. S. Unnikrishnan, T. Shiromizu

String theory, as well as the string inspired brane-world models such as the Randall-Sundrum (RS) one, suggest a modification of Newton&#39;s law of gravitation at small distance scales. Search for modifications of standard gravity is an active field of research in this context. It is well known that short range corrections to gravity would violate the Newto

J. Strecka, M. Hagiwara, P. Balaz, M. Jascur

The magnetization process of the spin-1 Heisenberg dimer model with axial and rhombic single-ion anisotropy terms is particularly investigated in connection with recent experimental high-field measurements performed on the single-crystal sample of the homodinuclear nickel(II) compound [Ni2(Medpt)2(ox)(H2O)2](ClO4)2.2H2O (Medpt=methyl-bis(3-aminopropyl)amine)

Simon Fu

Both external environmental selection and internal lower-level evolution are essential for an integral picture of evolution. This paper proposes that the division of internal evolution into DNA/RNA pattern formation (genotype) and protein functional action (phenotype) resolves a universal conflict between fitness and evolvability. Specifically, this paper ex

Joan S. Birman, Dennis Johnson, Andrew Putman

Let $f$ be the gluing map of a Heegaard splitting of a 3-manifold $W$. The goal of this paper is to determine the information about $W$ contained in the image of $f$ under the symplectic representation of the mapping class group. We prove three main results. First, we show that the first homology group of the three manifold together with Seifert's linking fo

Tomohiro Matsuda

We study ``hilltop&#39;&#39; curvatons that evolve on a convex potential. Hilltop curvatons evolving on the Hubble-induced potential are generic if supergravity is assumed in the theory. We do not consider curvatons whose potential is protected from $O(H)$ corrections, where $H$ is the Hubble parameter. We assume that the effective mass of a curvaton is expr

Mathieu Bouville, Rajeev Ahluwalia

We use phase field simulations to study composites made of two different ferroelastics (e.g., two types of martensite). The deformation of one material due to a phase transformation can elastically affect the other constituent and induce it to transform as well. We show that the phase transformation can then occur above its normal critical temperature and ev

Xin Wan, Zi-Xiang Hu, E. H. Rezayi, Kun Yang

We present a comprehensive numerical study of a microscopic model of the fractional quantum Hall system at filling fraction $ν= 5/2$, based on the disc geometry. Our model includes Coulomb interaction and a semi-realistic confining potential. We also mix in some three-body interaction in some cases to help elucidate the physics. We obtain a phase diagram, di

Bei Zeng, Xie Chen, Isaac L. Chuang

Teleportation is a crucial element in fault-tolerant quantum computation and a complete understanding of its capacity is very important for the practical implementation of optimal fault-tolerant architectures. It is known that stabilizer codes support a natural set of gates that can be more easily implemented by teleportation than any other gates. These gate

Dipendra Prasad, Ramin Takloo-Bighash

Methods of theta correspondence are used to analyze local and global Bessel models for $GSp(4)$ proving a conjecture of Gross and Prasad which describes these models in terms of local epsilon factors in the local case, and the non-vanishing of central critical $L$-value in the global case.

Xiaopeng Zhao

Cardiac alternans, a beat-to-beat alternation in action potential duration (at the cellular level) or in ECG morphology (at the whole heart level), is a marker of ventricular fibrillation, a fatal heart rhythm that kills hundreds of thousands of people in the US each year. Investigating cardiac alternans may lead to a better understanding of the mechanisms o

Alexander N. Dranishnikov, Yuli B. Rudyak

We prove that for any group of the cohomological dimension $n$ the $n$th power of the Berstein class of the group is nontrivial. This allows to prove the following Berstein-Svarc theorem for all $n$: Theorem. For a connected complex $X$ with $\dim X=\cat X=n$, the $n$th power of the Berstein class of $X$ is nontrivial. Previously it was known for $n\ge 3$. W

M. Wakamatsu, Y. Nakakoji

In the past few years, a lot of evidences have been accumulated, which indicate that the gluon polarization inside the nucleon is likely to be small at least at the low renormalization scales. On the other hand, the recent lattice QCD analyses suggest that the net orbital angular momentum carried by the quarks is nearly zero. There is also some indication no

Jason Harris, Dennis Zaritsky

We present a detailed reconstruction of the star-formation history of the Constellation III region in the Large Magellanic Cloud, to constrain the formation mechanism of this enigmatic feature. Star formation in Constellation III seems to have taken place during two distinct epochs: there is the 8-15 Myr epoch that had previously been recognized, but we also

Olexandr Ganyushkin, Volodymyr Mazorchuk, Benjamin Steinberg

Work of Clifford, Munn and Ponizovski{\uı} parameterized the irreducible representations of a finite semigroup in terms of the irreducible representations of its maximal subgroups. Explicit constructions of the irreducible representations were later obtained independently by Rhodes and Zalcstein and by Lallement and Petrich. All of these approaches make use

Chris Berg, Monica Vazirani

In this paper we give an alternate combinatorial description of the &#34;$(\ell,0)$-JM partitions&#34; (see \cite{F}) that are also $\ell$-regular. Our main theorem is the equivalence of our combinatoric and the one introduced by James and Mathas (\cite{JM}). The condition of being an $(\ell,0)$-JM partition is fundamentally related to the hook lengths of th

M. Gillon, A. H. M. J. Triaud, M. Mayor, D. Queloz

We report high-precision transit photometry for the recently detected planet HD 17156b. Using these new data with previously published transit photometry and radial velocity measurements, we perform a combined analysis based on a Markov Chain Monte Carlo approach. The resulting mass M_p = 3.09 (+0.22-0.17) M_Jup and radius R_p = 1.23 (+0.17-0.20) R_Jup for t

Ahmadreza Azimifard

Associated to a nonzero homomorphism $φ$ of a Banach algebra $A$, we regard special functionals, say $m_φ$, on certain subspaces of $A^\ast$ which provide equivalent statements to the existence of a bounded right approximate identity in the corresponding maximal ideal in $A$. For instance, applying a fixed point theorem yields an equivalent statement to the

S. G. Bhongale, S. J. J. M. F. Kokkelmans, Ivan H. Deutsch

We construct simple analytic models of the $S$-matrix, accounting for both scattering resonances and smooth background contributions for collisions that occur below the s-wave threshold. Such models are important for studying confinement-induced resonances such as those occurring in cold collisions of $^{133}$Cs atoms in separated sites of a polarization-gra

Gregory Ginot, Ping Xu

In this paper we study the cohomology of (strict) Lie 2-groups. We obtain an explicit Bott-Shulman type map in the case of a Lie 2-group corresponding to the crossed module $A\to 1$. The cohomology of the Lie 2-groups corresponding to the universal crossed modules $G\to \Aut(G)$ and $G\to \Aut^+(G)$ is the abutment of a spectral sequence involving the cohomo

Tommaso Roscilde

We investigate numerically the zero-temperature physics of the one-dimensional Bose-Hubbard model in an incommensurate cosine potential, recently realized in experiments with cold bosons in optical superlattices L. Fallani et al., Phys. Rev. Lett. 98, 130404, (2007)]. An incommensurate cosine potential has intermediate properties between a truly periodic and

Lijun Yang, Shaul Mukamel

We propose a three-pulse coherent ultrafast optical technique that is particularly sensitive to two-exciton correlations. Two Liouville-space pathways for the density matrix contribute to this signal which reveals double quantum coherences when displayed as a two-dimensional correlation plot. Two-exciton couplings spread the cross peaks along both axes, crea

David Bernholdt, Shishir Bharathi, David Brown, Kasidit Chanchio

Understanding the earth&#39;s climate system and how it might be changing is a preeminent scientific challenge. Global climate models are used to simulate past, present, and future climates, and experiments are executed continuously on an array of distributed supercomputers. The resulting data archive, spread over several sites, currently contains upwards of

Marcelo Salgado, David Martinez-del Rio

The initial value problem of scalar-tensor theories of gravity (STT) is analyzed in the physical (Jordan) frame using a 3+1 decomposition of spacetime. A first order strongly hyperbolic system is obtained for which the well posedness of the Cauchy problem can be established. We provide two simple applications of the 3+1 system of equations: one for static an

Massimo Fornasier, Carola-Bibiane Schönlieb

This paper is concerned with the numerical minimization of energy functionals in Hilbert spaces involving convex constraints coinciding with a semi-norm for a subspace. The optimization is realized by alternating minimizations of the functional on a sequence of orthogonal subspaces. On each subspace an iterative proximity-map algorithm is implemented via \em

Michel Versluis, Barbara Schmitz, Anna von der Heydt, Detlef Lohse

Fluid dynamics video: Snapping shrimp produce a snapping sound by an extremely rapid closure of their snapper claw. Our high speed imaging of the claw closure has revealed that the sound is generated by the collapse of a cavitation bubble formed in a fast flowing water jet forced out from the claws during claw closure. The produced sound originates from the

Ian Foster

Licklider advocated in 1960 the construction of computers capable of working symbiotically with humans to address problems not easily addressed by humans working alone. Since that time, many of the advances that he envisioned have been achieved, yet the time spent by human problem solvers in mundane activities remains large. I propose here four areas in whic

Benjamin Steinberg

We answer a question of Margolis from 1997 by establishing that the maximal subgroup of the minimal ideal of a finitely generated free profinite monoid is a free profinite group. More generally if $\mathbf H$ is variety of finite groups closed under extension and containing $\mathbb Z/p\mathbb Z$ for infinitely may primes $p$, the corresponding result holds

Yuri Bakhtin, Christine Heitsch

We consider large random trees under Gibbs distributions and prove a Large Deviation Principle (LDP) for the distribution of degrees of vertices of the tree. The LDP rate function is given explicitly. An immediate consequence is a Law of Large Numbers for the distribution of vertex degrees in a large random tree. Our motivation for this study comes from the

M. C. Goorden, Ph. Jacquod, J. Weiss

We investigate the conductance through and the spectrum of ballistic chaotic quantum dots attached to two s-wave superconductors, as a function of the phase difference $ϕ$ between the two order parameters. A combination of analytical techniques -- random matrix theory, Nazarov&#39;s circuit theory and the trajectory-based semiclassical theory -- allows us to

T. Giamarchi, Ch. Rüegg, O. Tchernyshyov

The elementary excitations in antiferromagnets are magnons, quasiparticles with integer spin and Bose statistics. In an experiment their density is controlled efficiently by an applied magnetic field and can be made finite to cause the formation of a Bose-Einstein condensate (BEC). Studies of magnon condensation in a growing number of magnetic materials prov

The BABAR Collaboration, B. Aubert

We present a measurement of $D^0$-$\bar{D^0}$ mixing parameters using the ratios of lifetimes extracted from a sample of $D^0$ mesons produced through the process $D^{*+}\to\D^0π^+$, that decay to $K^{+}π^{-}$, K^{-}K^{+}$, or $π^-π^+$. The Cabibbo-suppressed modes $K^{-}K^{+}$ and $π^-π^+$ are compared to the Cabibbo-favored mode $K^{+}π^{-}$ to obtain a me

Umberto Marini Bettolo Marconi, Simone Melchionna

We consider a system of interacting particles subjected to Langevin inertial dynamics and derive the governing time-dependent equation for the one-body density. We show that, after suitable truncations of the Bogoliubov-Born-Green-Kirkwood-Yvon hierarchy, and a multiple time scale analysis, we obtain a self-consistent equation involving only the one-body den

S. Melchionna, U. Marini Bettolo Marconi

We present a lattice-based numerical method to describe the non equilibrium behavior of a simple fluid under non-uniform spatial conditions. The evolution equation for the one-particle phase-space distribution function is derived starting from a microscopic description of the system. It involves a series of approximations which are similar to those employed

Pedro Massey

Let $\mathcal A\subseteq \mat$ be a unital $*$-subalgebra of the algebra $\mat$ of all $n\times n$ complex matrices and let $B$ be an hermitian matrix. Let $\U_n(B)$ denote the unitary orbit of $B$ in $\mat$ and let $\mathcal E_\mathcal A$ denote the trace preserving conditional expectation onto $\mathcal A$. We give an spectral characterization of the set $

Marco Baldi, Franco Chiaraluce, Torleiv Kløve

Computation of the undetected error probability for error correcting codes over the Z-channel is an important issue, explored only in part in previous literature. In this paper we consider the case of Varshamov-Tenengol&#39;ts codes, by presenting some analytical, numerical, and heuristic methods for unveiling this additional feature. Possible comparisons wi

Tanya Khovanova

There are several standard procedures used to create new sequences from a given sequence or from a given pair of sequences. In this paper I discuss the most popular of these procedures. For each procedure, I give a definition and provide examples based on three famous sequences: the natural numbers, the prime numbers and the Fibonacci numbers. I also add my

C. Greco, M. Dall&#39;Ora, G. Clementini, V. Ripepi

We report on the detection of variable stars in the Canes Venatici II (CVn II) dwarf spheroidal galaxy, a new satellite of the Milky Way recently discovered by the Sloan Digital Sky Survey. We also present a V, B-V color-magnitude diagram that reaches V = 25.5 mag, showing the galaxy&#39;s main sequence turn off at V = 24.5 mag and revealing several candidat

Don N. Page

Scientific theories need to be testable by observations, say using Bayes&#39; theorem. A complete theory needs at least the three parts of dynamical laws for specified physical variables, the correct solution of the dynamical laws (boundary conditions), and the connection with observations or experience or conscious perceptions (laws of psycho-physical paral

Manik Lal Das, Ashutosh Saxena, Ved P. Gulati

Password-based authentication schemes are the most widely used techniques for remote user authentication. Many static ID-based remote user authentication schemes both with and without smart cards have been proposed. Most of the schemes do not allow the users to choose and change their passwords, and maintain a verifier table to verify the validity of the use

F. Aceff-Sanchez, L. Del Riego Senior

Conics in the Euclidean space have been known for their geometrical beauty and also for their power to model several phenomena in real life. It usually happens that when thinking about the conics in a semi-Riemannian manifold, the equations and the graphs that come to mind are those of the quadratic Euclidean equations. For example, a circle is always percei

Arafat Gabareen Mokhtar

The charmonium-like states, Y(4260), Y(4350), produced via initial state radiation, as well as the X(3872), and Y(3940), produced in B meson decays from the BABAR B-factory are reviewed. These mesons do not seem consistent with conventional charmonium models, and several alternate hypotheses have been proposed to explain these new discoveries.

Andreas U. Schmidt, Nicolai Kuntze, Joerg Abendroth

We propose a concept for authorisation using the location of a mobile device and the enforcement of location-based policies. Mobile devices enhanced by Trusted Computing capabilities operate an autonomous and secure location trigger and policy enforcement entity. Location determination is two-tiered, integrating cell-based triggering at handover with precisi

E. Piña

The alternating knots, links and twists projected on the $S_2$ sphere were identified with the phase space of a Hamiltonian dynamic system of one degree of freedom. The saddles of the system correspond to the crossings, the edges correspond to the stable and unstable manifolds connecting the saddles. Each face is then oriented in one of two different senses

Jim Brown

Let $k > 3$ be an integer and $p$ a prime with $p > 2k-2$. Let $f$ be a newform of weight $2k-2$ and level 1 so that $f$ is ordinary at $p$ and $\barρ_{f}$ is irreducible. Under some additional hypotheses we prove that $ord_{p}(L_{alg}(k,f)) \leq ord_{p}(# S)$ where $S$ is the Pontryagin dual of the Selmer group associated to $ρ_{f} \otimes ε^{1-k}$ with $ε$

S. Hacyan

Poincaré held the view that geometry is a convention and cannot be tested experimentally. This position was apparently refuted by the general theory of relativity and the successful confirmation of its predictions; unfortunately, Poincaré did not live to defend his thesis. In this paper, I argue that: 1) Contrary to what many authors have claimed, non-euclid

Aaron J. Amsel, Donald Marolf, Amitabh Virmani

We use AdS/CFT to investigate i) high energy collisions with balls of deconfined plasma surrounded by a confining phase and ii) the rapid localized heating of a deconfined plasma. Both of these processes are dual to collisions with black holes, where they result in the nucleation of a new &#34;arm&#34; of the horizon reaching out in the direction of the inci

Luis M. A. Bettencourt, Vadas Gintautas, Michael I. Ham

We present a general information theoretic approach for identifying functional subgraphs in complex networks where the dynamics of each node are observable. We show that the uncertainty in the state of each node can be expressed as a sum of information quantities involving a growing number of correlated variables at other nodes. We demonstrate that each term

U. N. Bhosle, L. Brambila-Paz, P. E. Newstead

We study coherent systems of type $(n,d,n+1)$ on a Petri curve $X$ of genus $g\ge2$. We describe the geometry of the moduli space of such coherent systems for large values of the parameter $α$. We determine the top critical value of $α$ and show that the corresponding ``flip&#39;&#39; has positive codimension. We investigate also the non-emptiness of the mod

E. M. Herzig, K. A. White, A. B. Schofield, W. C. K. Poon

Recent large-scale computer simulations suggest that it may be possible to create a new class of soft solids, called `bijels&#39;, by stabilizing and arresting the bicontinuous interface in a binary liquid demixing via spinodal decomposition using particles that are neutrally wetted by both liquids. The interfacial layer of particles is expected to be semi-p

Jean Dolbeault, Bruno Nazaret, Giuseppe Savaré

The goal of this paper is to give a non-local sufficient condition for generalized Poincaré inequalities, which extends the well-known Bakry-Emery condition. Such generalized Poincaré inequalities have been introduced by W. Beckner in the gaussian case and provide, along the Ornstein-Uhlenbeck flow, the exponential decay of some generalized entropies which i

Robert V. Kohn, Stephen P. Shipman

Arrays of cylindrical metal micro-resonators embedded in a dielectric matrix were proposed by Pendry, et. al., in 1999 as a means of creating a microscopic structure that exhibits strong bulk magnetic behavior at frequencies not realized in nature. This behavior arises for H-polarized fields in the quasi-static regime, in which the scale of the micro-structu

Andrea De Luca

Central Compact Objects (CCOs) are a handful of soft X-ray sources located close to the centers of Supernova Remnants and supposed to be young, radio-quiet Isolated Neutron Stars (INSs). A clear understanding of their physics would be crucial in order to complete our view of the birth properties of INSs. We will review the phenomenologies of CCOs, underlinin

F. Pfuner, L. Degiorgi, K. Y. Shin, I. R. Fisher

We investigate the rare-earth polychalcogenide $R_2$Te$_5$ ($R$=Nd, Sm and Gd) charge-density-wave (CDW) compounds by optical methods. From the absorption spectrum we extract the excitation energy of the CDW gap and estimate the fraction of the Fermi surface which is gapped by the formation of the CDW condensate. In analogy to previous findings on the relate