June 2007 arXiv papers

Richard J. Barton

In this paper, we present a unified approach to function approximation in reproducing kernel Hilbert spaces (RKHS) that establishes a previously unrecognized optimality property for several well-known function approximation techniques, such as minimum-norm interpolation, smoothing splines, and pseudo-inverses. We consider the problem of approximating a funct

Anirban Basu

We consider the effect of the R^4 term in type IIA string theory on the supergravity background dual to N_c D4 branes compactified on a circle with supersymmetry breaking boundary conditions. We study the dynamics of D8 branes in this perturbed geometry in the probe approximation. This leads to an analysis of higher derivative corrections in holographic QCD

Gabor Zsolt Toth

This thesis contains three main parts, which are largely independent. In the first part we deal with the boundary bootstrap in supersymmetric factorized scattering theory. We give a description of supersymmetry in the case when the space is a half-line and present rules for the determination of the representations in which higher level boundary bound states

Alexey Teplinsky

We prove that a $C^{3+β}$-smooth orientation-preserving circle diffeomorphism with rotation number in Diophantine class $D_δ$, $0<β<δ<1$, is $C^{2+β-δ}$-smoothly conjugate to a rigid rotation.

Hirotaka Yoshino, Tetsuya Shiromizu

We study collisions of two high-energy closed strings in the framework of $D$-dimensional general relativity. The model of a high-energy closed string is introduced as a {/it pp}-wave generated by a ring-shaped source with the radius $R$. At the instant of the collision, the positions of two strings are assumed to coincide precisely. In this setup, we study

G. Klupp, F. Borondics, É. Kováts, Á. Pekker

C60-C8H8 and C70-C8H8 are prototypes of rotor-stator cocrystals. We present infrared and Raman spectra of these materials and show how the rotor-stator nature is reflected in their vibrational properties. We measured the vibrational spectra of the polymer phases poly(C60C8H8) and poly(C70C8H8) resulting from a solid state reaction occurring on heating. Based

Michael Skotiniotis, Aidan Roy, Barry C. Sanders

We investigate the strengths and limitations of the Spekkens toy model, which is a local hidden variable model that replicates many important properties of quantum dynamics. First, we present a set of five axioms that fully encapsulate Spekkens&#39; toy model. We then test whether these axioms can be extended to capture more quantum phenomena, by allowing op

Nicolas Andruskiewitsch, Gaston Andres Garcia

Let G be a connected, simply connected, simple complex algebraic group and let e be a primitive l-th root of 1, with l odd and 3 does not divide l if G is of type G_{2}. We determine all Hopf algebra quotients of the quantized coordinate algebra of G at e.

P. Simon, P. Watts, P. Schneider, H. Hoekstra

The weak gravitational lensing effect, small coherent distortions of galaxy images by means of a gravitational tidal field, can be used to study the relation between the matter and galaxy distribution. In this context, weak lensing has so far only been used for considering a second-order correlation function that relates the matter density and galaxy number

R. Srikanth, Subhashish Banerjee

Squeezing of a thermal bath introduces new features absent in an open quantum system interacting with an uncorrelated (zero squeezing) thermal bath. The resulting dynamics, governed by a Lindblad-type evolution, extends the concept of a generalized amplitude damping channel, which corresponds to a dissipative interaction with a purely thermal bath. Here we p

E. A. Yelland, J. Singleton, C. H. Mielke, N. Harrison

We report the observation of quantum oscillations in the underdoped cuprate superconductor YBa2Cu4O8 using a tunnel-diode oscillator technique in pulsed magnetic fields up to 85T. There is a clear signal, periodic in inverse field, with frequency 660+/-15T and possible evidence for the presence of two components of slightly different frequency. The quasipart

Michele Caselle, Martin Hasenbusch, Marco Panero

We provide accurate Monte Carlo results for the free energy of interfaces with periodic boundary conditions in the 3D Ising model. We study a large range of inverse temperatures, allowing to control corrections to scaling. In addition to square interfaces, we study rectangular interfaces for a large range of aspect ratios u=L_1/L_2. Our numerical results are

Bjoern Baeuchle, Horst Stoecker, Laszlo Csernai

The shape of Mach Cones in central lead on lead collisions at $\sqrt{s_{NN}} = 5.5$ TeV are calculated and discussed using MACE.

Gianluca Grignani, Luca Griguolo, Nicola Mori, Domenico Seminara

We study the thermodynamics of maximally supersymmetric U(N) Yang-Mills theory on $\mathds{R}\times S^2$ at large $N$. The model arises as a consistent truncation of ${\cal N}=4$ super Yang-Mills on $\mathds{R}\times S^3$ and as the continuum limit of the plane-wave matrix model expanded around the $N$ spherical membrane vacuum. The theory has an infinite nu

G. Vereshkov, N. Volchanskiy

We adopt the vector-meson-dominance approach to investigate Q^2-evolution of N-R transition form factors (N denotes nucleon and R an excited resonance) in the first and second resonance regions. The developed model is based upon conventional NRγ-interaction Lagrangians, introducing three form factors for spin-3/2 resonances and two form factors for spin-1/2

Anton Kuzyk, Mika Pettersson, J. Jussi Toppari, Tommi K. Hakala

We use molecules to couple light into and out of microscale plasmonic waveguides. Energy transfer, mediated by surface plasmons, from donor molecules to acceptor molecules over ten micrometer distances is demonstrated. Also surface plasmon coupled emission from the donor molecules is observed at similar distances away from the excitation spot. The lithograph

J. Gough, M. R. James

The purpose of this paper is to present simple and general algebraic methods for describing series connections in quantum networks. These methods build on and generalize existing methods for series (or cascade) connections by allowing for more general interfaces, and by introducing an efficient algebraic tool, the series product. We also introduce another pr

Ulrich Bunke, Thomas Schick

We construct an analytic multiplicative model of smooth K-theory. We further introduce the notion of a smooth K-orientation of a proper submersion and define the associated push-forward which satisfies functoriality, compatibility with pull-back diagrams, and projection and bordism formulas. We construct a multiplicative lift of the Chern character from smoo

Hsin-Chia Cheng, John F. Gunion, Zhenyu Han, Guido Marandella

We describe a kinematic method which is capable of determining the overall mass scale in SUSY-like events at a hadron collider with two missing (dark matter) particles. We focus on the kinematic topology in which a pair of identical particles is produced with each decaying to two leptons and an invisible particle (schematically, $pp\to YY+jets$ followed by e

A. E. Shalyt-Margolin, V. I. Strazhev, A. Ya. Tregubovich

Geometric phase that manifests itself in number of optic and nuclear experiments is shown to be a useful tool for realization of quantum computations in so called holonomic quantum computer model (HQCM). This model is considered as an externally driven quantum system with adiabatic evolution law and finite number of the energy levels. The corresponding evolu

Nobuki Takayama

We will introduce a modified system of A-hypergeometric system (GKZ system) by applying a change of variables for Groebner deformations and study its Groebner basis and the indicial polynomials along the &#34;exceptional hypersurface&#34;.

Karthik Shankar, Bernard F. Whiting

When a charge is held static near a constant density spherical star, it experiences a self-force which is significantly different from the force it would experience when placed near a black hole of the same mass. In this paper, an expression for the self-force (as measured by a locally inertial observer) is given %explicitly calculated for an insulating Schw

Abraham G. Kofman, Alexander N. Korotkov

We analyze conditions for violation of the Bell inequality in the Clauser-Horne-Shimony-Holt form, focusing on the Josephson phase qubits. We start the analysis with maximum violation in the ideal case, and then take into account the effects of the local measurement errors and decoherence. A special attention is paid to configurations of the qubit measuremen

Ibrahim Assem, Thomas Bruestle, Ralf Schiffler

We give a criterion allowing to verify whether or not two tilted algebras have the same relation-extension (thus correspond to the same cluster-tilted algebra). This criterion is in terms of a combinatorial configuration in the Auslander-Reiten quiver of the cluster-tilted algebra, which we call local slice.

Hui-Ling Gu

In this short paper, we will give a simple and transcendental proof for Mok&#39;s theorem of the generalized Frankel conjecture. This work is based on the maximum principle in \cite{BS2} proposed by Brendle and Schoen.

Dang Duc Trong, Truong Trung Tuyen

Let $ϕ$ be a nontrivial function of $L^1(\RR)$. For each $s\geq 0$ we put \begin{eqnarray*} p(s)=-\log \int_{|t|\geq s}|ϕ(t)|dt. \end{eqnarray*} If $ϕ$ satisfies \begin{equation} \lim_{s\to \infty}\frac{p(s)}{s}=\infty ,\label{170506.1} \end{equation} we obtain asymptotic estimates of the size of small-valued sets $B_ε=\{x\in\RR : |\hatϕ(x)|\leq ε, |x|\leq R

Kyle Pula

A complete edge-colored graph or multigraph is called Gallai if it lacks rainbow triangles. We give a construction of all finite Gallai multigraphs.

L. A. Melnikovsky

We consider reflection of the first and the second sound waves by a rigid flat wall in superfluid. Nontrivial dependence of the reflection coefficients on the angle of incidence is obtained. Sound conversion is predicted at slanted incidence.

M. E. J. Newman

We give an exact solution for the complete distribution of component sizes in random networks with arbitrary degree distributions. The solution tells us the probability that a randomly chosen node belongs to a component of size s, for any s. We apply our results to networks with the three most commonly studied degree distributions -- Poisson, exponential, an

Noriyoshi Ishii, Takumi Doi, Makoto Oka, Hideo Suganuma

Five-quark (5Q) picture of Lambda(1405) is studied using quenched lattice QCD with an exotic 5Q operator of N\bar{K} type. To discreminate mere N\bar{K} and Σπscattering states, Hybrid Boundary Condition (HBC), a flavor-dependent boundary condition, is imposed on the quark fields along spatial direction. 5Q mass m_{5Q}\simeq 1.89 GeV is obtained after the ch

Peng Gao

We study finite sections of weighted Carleman&#39;s inequality following the approach of De Bruijn. Similar to the unweighted case, we obtain an asymptotic expression for the optimal constant.

Konstantin Khanin, Alexey Teplinsky

We prove that a $C^{2+α}$-smooth orientation-preserving circle diffeomorphism with rotation number in Diophantine class $D_δ$, $0<δ<α\le1$, is $C^{1+α-δ}$-smoothly conjugate to a rigid rotation. We also derive the most precise version of Denjoy&#39;s inequality for such diffeomorphisms.

J. Machta, C. M. Newman, D. L. Stein

Magnetic ordering at low temperature for Ising ferromagnets manifests itself within the associated Fortuin-Kasteleyn (FK) random cluster representation as the occurrence of a single positive density percolating network. In this paper we investigate the percolation signature for Ising spin glass ordering -- both in short-range (EA) and infinite-range (SK) mod

Christian Schulze, Dietrich Stauffer

When a region is conquered by people speaking another language, we assume within the Schulze model that at each iteration each person with probability s shifts to the conquering language. The time needed for the conquering language to become dominating is about 2/s for directed Barabasi-Albert networks, but diverges on the square lattice for decreasing s at

Paul A. Crowther

We review the contribution of Hubble Space Telescope to the study of hot, luminous stars. Optical and IR imaging have permitted spatially resolved observations of young, massive clusters within Local Group galaxies, such as R136, NGC 3603 and Arches, revealing unprecedented concentrations of very massive O stars. UV spectroscopy of field OB stars in the Mage

Artorix de la Cruz de Ona

In this paper a new approach to obtain the interface propagation speed in superconductors by means of a variationalme thod is introduced. The results of the approach proposed coincide with the numerical simulations. The hyperbolic differential equations are introduced as an extension of the modelin order to take into account delay effects in the front propag

L. M. Rico, M. Kirchbach

We gauge the direct product of the Proca with the Dirac equation that describes the coupling to the electromagnetic field of the spin-cascade (1/2,3/2) residing in the four-vector spinor and analyze propagation of its wave fronts in terms of the Courant-Hilbert criteria. We show that the differential equation under consideration is unconditionally hyperbolic

Martin Stuetz, Simon Groeblacher, Thomas Jennewein, Anton Zeilinger

The experimental realization of multidimensional quantum states may lead to unexplored and interesting physics, as well as advanced quantum communication protocols. The orbital angular momentum of photons is a well suitable discrete degree of freedom for implementing high-dimensional quantum systems. The standard method to generate and manipulate such photon

K. J. Eskola, V. J. Kolhinen, H. Paukkunen, C. A. Salgado

In this talk, we present the results from our recent global reanalysis of nuclear parton distribution functions (nPDFs), where the DGLAP-evolving nPDFs are constrained by nuclear hard process data from deep inelastic $l+A$ scattering (DIS) and the Drell-Yan (DY) process in $p+A$ collisions, and by sum rules. The main improvements over our earlier work {\em E

C. Sivaram

Planck introduced his famous units of mass, length and time a hundred years ago. The many interesting facets of the Planck mass and length are explored. The Planck mass ubiquitously occurs in astrophysics, cosmology, quantum gravity, string theory, etc. Current aspects of its implications for unification of fundamental interactions, energy dependence of coup

Damian C. Swift, Dennis L. Paisley, Kenneth J. McClellan, Graeme J. Ackland

The pressure-volume-temperature equation of state of the intermetallic compound NiAl was calculated theoretically, and compared with experimental measurements. Electron ground states were calculated for NiAl in the CsCl structure, using density functional theory, and were used to predict the cold compression curve and the density of phonon states. The Rose f

M. Kalam, F. Rahaman, S. Mondal

Recently, Li and Liu have studied global monoole of tachyon in a four dimensional static space-time. We analyze the motion of massless and massive particles around tachyon monopole. Interestingly, for the bending of light rays due to tachyon monopole instead of getting angle of deficit we find angle of surplus. Also we find that the tachyon monopole exerts a

Nicolas Bonneau, Mérouane Debbah, Eitan Altman, Are Hjørungnes

In this contribution, the performance of a multi-user system is analyzed in the context of frequency selective fading channels. Using game theoretic tools, a useful framework is provided in order to determine the optimal power allocation when users know only their own channel (while perfect channel state information is assumed at the base station). We consid

Itaru Mitoma, Seiki Nishikawa

In an abstract Wiener space setting, we constract a rigorous mathematical model of the one-loop approximation of the perturbative Chern-Simons integral, and derive its explicit asymptotic expansion for stochastic Wilson lines.

Olivier Lafitte

We study the stability of the system of the Euler equation in the neighborhood of a stationary profile associated with the quasi isobaric model in a gravity field. This stationary profile is not bounded below, hence the operator is not coercive. We use this linear result to deduce a nonlinear result

M. S. Santhanam, V. B. Sheorey, Arul Lakshminarayan

We study entanglement in two coupled quartic oscillators. It is shown that the entanglement, as measured by the von Neumann entropy, increases with the classical chaos parameter for generic chaotic eigenstates. We consider certain isolated periodic orbits whose bifurcation sequence affects a class of quantum eigenstates, called the channel localized states.

Damian C. Swift, Achim Seifter, David B. Holtkamp, Vincent W. Yuan

Neutron resonance spectrometry (NRS) has been used to measure the temperature inside Mo samples during shock loading. The temperatures obtained were significantly higher than predicted assuming ideal hydrodynamic loading. The effect of plastic flow and non-ideal projectile behavior were assessed. Plastic flow was calculated self-consistently with the shock j

Shuji Matsuura, Mai Shirahata, Mitsunobu Kawada, Yasuo Doi

We report initial results of far-infrared observations of the Lockman hole with Far-Infrared Surveyor (FIS) onboard the AKARI infrared satellite. On the basis of slow scan observations of a 0.6 deg x 1.2 deg contiguous area, we obtained source number counts at 65, 90 and 140 um down to 77, 26 and 194 mJy (3 sigma), respectively. The counts at 65 and 140 um s

Grover A. Swartzlander,, Raul I. Hernandez-Aranda

Rankine vortex charateristics of a partially coherent optical vortex are explored using classical and physical optics. Unlike a perfectly coherent vortex mode, the circulation is not quantized. Excess circulation is predicted owing to the wave nature of the composite vortex fields. Based on these findings we propose a vortex stellar interferometer.

Hui-Ling Gu

In this paper, we proved a compactness result about Riemannian manifolds with an arbitrary pointwisely pinched Ricci curvature tensor.

Hui-Ling Gu, Xi-Ping Zhu

In this paper we prove the existence of Type II singularities for the Ricci flow on $S^{n+1}$ for all $n\geq 2$.

Dimitar Jetchev, Kristin Lauter, William Stein

Kolyvagin used Heegner points to associate a system of cohomology classes to an elliptic curve over $\Q$ and conjectured that the system contains a non-trivial class. His conjecture has profound implications on the structure of Selmer groups. We provide new computational and theoretical evidence for Kolyvagin&#39;s conjecture. More precisely, we explicitly c

Ruslan Prozorov, Matthew D. Vannette, Stephanie A. Law, Sergey L. Bud&#39;ko

High resolution measurements of the dynamic magnetic susceptibility are reported for ferromagnetic re-entrant superconductor, ErRh$_{4}$B$_{4}$. Detailed investigation of the coexisting regime reveals unusual temperature-asymmetric and magnetically anisotropic behavior. The superconducting phase appears via a series of discontinuous steps upon warming from t

E. Gallo, S. Migliari, S. Markoff, J. Tomsick

(Abridged) Among the various issues that remain open in the field of accretion onto black hole X-ray binaries (BHBs) is the way the gas accretes at very low Eddington ratios, in the so-called quiescent regime. While there is general agreement that the X-rays are produced by a population of high-energy electrons near to the BH, the controversy comes about in

Taeyoung Lee, Melvin Leok, N. Harris McClamroch

Euler-Lagrange equations and variational integrators are developed for Lagrangian mechanical systems evolving on a product of two-spheres. The geometric structure of a product of two-spheres is carefully considered in order to obtain global equations of motion. Both continuous equations of motion and variational integrators completely avoid the singularities

Tsuguo Mogami

A simpler method of quantization is given for massive gauge theories. This method gives the same results as those of the conventional massive gauge theory with ghost and Higgs fields under the Higgs mass. Besides, we point out physical importance of helicity zero states in non-Abelian gauge theories even in massless case. Furthermore, forms of mass terms tha

Maria A. Avino-Diaz

A probabilistic structure on sequential dynamical systems is introduced here, the new model will be called Probabilistic Sequential Network, PSN. The morphisms of Probabilistic Sequential Networks are defined using two algebraic conditions. It is proved here that two homomorphic Probabilistic Sequential Networks have the same equilibrium or steady state prob

Wayne L. Waldron, Joseph P. Cassinelli

Chandra high energy resolution observations have now been obtained from numerous non-peculiar O and early B stars. The observed X-ray emission line properties differ from pre-launch predictions, and the interpretations are still problematic. We present a straightforward analysis of a broad collection of OB stellar line profile data to search for morphologica

Aldo Procacci

A convergence criterion of cluster expansion is presented in the case of an abstract polymer system with general pair interactions (i.e. not necessarily hard core or repulsive). As a concrete example, the low temperature disordered phase of the BEG model with infinite range interactions, decaying polynomially as $1/r^{d+λ}$ with $λ>0$, is studied.

Marko Horvat

Although it might not be self-evident, it is in fact entirely possible to calculate the probability of detecting alien radio signals by understanding what types of extraterrestrial radio emissions can be expected and what properties these emissions can have. Using the Drake equation as the obvious starting point, and logically identifying and enumerating con

Michael Dine, Nathan Seiberg, Scott Thomas

We interpret the current experimental limit on the lightest Higgs boson mass to suggest that if nature is supersymmetric, there are additional interactions beyond those of the MSSM coming from new degrees of freedom around the TeV scale. Within an effective field theory analysis, the leading order corrections to the MSSM are described in terms of only two op

Hirotaka Irie

We study boundary states in (p,q) minimal superstring theory, combining the explicit form of matter wave functions. Within the modular bootstrap framework, Cardy states of (p,q) minimal superconformal field theory are completely determined in both cases of the different supercharge combinations, and the remaining consistency checks in the super-Liouville cas

J. P. Zibin, A. Moss, D. Scott

We discuss the time dependence and future of the Cosmic Microwave Background (CMB) in the context of the standard cosmological model, in which we are now entering a state of endless accelerated expansion. The mean temperature will simply decrease until it reaches the effective temperature of the de Sitter vacuum, while the dipole will oscillate as the Sun or

D. M. Silevitch, C. M. S. Gannarelli, A. J. Fisher, G. Aeppli

A transverse magnetic field is used to scan the diagonal and off-diagonal susceptibility of the uniaxial quantum magnet, $\text{LiHo}_{0.045}\text{Y}_{0.955}\text{F}_4$. Clusters of strongly-coupled spins act as the primary source for the response functions, which result from a field-induced quantum projection of the system into a classically forbidden (mean

Dave Bacon, Thomas Decker

The optimization of measurements for the state distinction problem has recently been applied to the theory of quantum algorithms with considerable successes, including efficient new quantum algorithms for the non-abelian hidden subgroup problem. Previous work has identified the optimal single copy measurement for the hidden subgroup problem over abelian grou

Christoph Mayrhofer, Anton Rebhan, Peter van Nieuwenhuizen, Robert Wimmer

We present an explicit calculation of the one-loop quantum corrections to the mass and the two central charges of the kink solution of an N=(2,2) supersymmetric CP^1 model with twisted mass, using supersymmetry preserving dimensional regularization adapted to solitons. We find that the quantum corrections of the mass and one of the central charges are nontri

Igor Nikolaev

A covariant functor from the category of the complex tori to the category of the Effros-Shen algebras is constructed. The functor maps isomorphic complex tori to the stably isomorphic Effros-Shen algebras. Our construction is based on the Teichmueller theory of the Riemann surfaces.

B. Casal

We present recent CDF results based on approximately 1 fb$^{-1}$ of $p\bar p$ collisions at $\sqrt s = 1.96$ TeV delivered at Fermilab Tevatron. Results shown include the observation of the $B_s$ oscillation frequency, the first observation of bottom baryon $Σ_b^{(*)\pm}$ states, updates on $B$ hadrons lifetimes, and searches for rare decays in the $b\to sμ^

Liu Zhao

We analyze some exact chain-shaped black hole solutions in 5-dimensional spacetime. Unlike usual black string and black ring solutions, the topology of the horizons of the new solutions are neither $\mathbb{R}\times R^{2}$ nor $S^1\times S^2$ but rather like several topological spheres concatenating each other at single points. The shape of the horizon sugge

Nikodem J. Poplawski

The purely affine, metric-affine and purely metric formulation of general relativity are dynamically equivalent and the relation between them is analogous to the Legendre relation between the Lagrangian and Hamiltonian dynamics. We show that one cannot construct a dynamically equivalent, purely affine Lagrangian from a metric-affine or metric F(R) Lagrangian

Alberto Sicilia, Jeferson J. Arenzon, Alan J. Bray, Leticia F. Cugliandolo

We study the distribution of domain areas, areas enclosed by domain boundaries (&#39;&#39;hulls&#39;&#39;), and perimeters for curvature-driven two-dimensional coarsening, employing a combination of exact analysis and numerical studies, for various initial conditions. We show that the number of hulls per unit area, $n_h(A,t) dA$, with enclosed area in the in

K. E. Johnson, J. E. Hibbard, S. C. Gallagher, J. C. Charlton

Compact groups of galaxies provide a unique environment to study the mechanisms by which star formation occurs amid continuous gravitational encounters. We present 2MASS (JHK), Spitzer IRAC (3.5-8 micron) and MIPS (24 micron) observations of a sample of twelve Hickson Compact Groups (HCGs 2, 7, 16, 19, 22, 31, 42, 48, 59, 61, 62, and 90) that includes a tota

Wim van Dam, G. Mauro D&#39;Ariano, Artur Ekert, Chiara Macchiavello

We address the problem of estimating the phase phi given N copies of the phase rotation u(phi) within an array of quantum operations in finite dimensions. We first consider the special case where the array consists of an arbitrary input state followed by any arrangement of the N phase rotations, and ending with a POVM. We optimise the POVM for a given input

Shimul Akhanjee, Joseph Rudnick

The destruction of quasi-long range crystalline order as a consequence of strong disorder effects is shown to accompany the strict localization of all classical plasma modes of one-dimensional Wigner crystals at T=0. We construct a phase diagram that relates the structural phase properties of Wigner crystals to a plasmon delocalization transition recently re

Andriy Haydys

We study relations between quaternionic Riemannian manifolds admitting different types of symmetries. We show that any hyperKahler manifold admitting hyperKahler potential and triholomorphic action of S^1 can be constructed from another hyperKahler manifold (of lower dimention) with an action of S^1 which fixes one complex structure and rotates the other two

Cyril Pitrou

This article investigates the collisionless Boltzmann equation up to second order in the cosmological perturbations. It describes the gauge dependence of the distribution function and the construction of a gauge invariant distribution function and brightness, and then derives the gauge invariant fluid limit.

Georgi S. Medvedev, Yun Yoo

The present paper points out to a novel scenario for formation of chaotic attractors in a class of models of excitable cell membranes near an Andronov-Hopf bifurcation (AHB). The mechanism underlying chaotic dynamics admits a simple and visual description in terms of the families of one-dimensional first-return maps, which are constructed using the combinati

A. E. Feiguin, E. Rezayi, C. Nayak, S. Das Sarma

We develop the Density Matrix Renormalization Group (DMRG) technique for numerically studying incompressible fractional quantum Hall (FQH) states on the sphere. We calculate accurate estimates for ground state energies and excitationgaps at FQH filling fractions ν=1/3 and ν=5/2 for systems that are almost twice as large as the largest ever studied by exact d

F. J. Cao, M. Feito

Feedback controlled ratchets are thermal rectifiers that use information on the state of the system to operate. We study the effects of time delays in the feedback for a protocol that performs an instantaneous maximization of the center-of-mass velocity in the many particle case. For small delays the center-of-mass velocity decreases for increasing delays (a

M. Meyer

All but three (M87, BL Lac and 3C 279) extragalactic sources detected so far at very high energy (VHE) gamma-rays belong to the class of high-frequency peaked BL Lac (HBL) objects. This suggested to us a systematic scan of candidate sources with the MAGIC telescope, based on the compilation of X-ray blazars by Donato et al. (2001). The observations took plac

Jinfeng Liao, Edward Shuryak

In this paper we study a methodical problem related to the magnetic scenario recently suggested and initiated by the authors \cite{Liao_ES_mono} to understand the strongly coupled quark-gluon plasma (sQGP): the electric flux tube in monopole plasma. A macroscopic approach, interpolating between Bose condensed (dual superconductor) and classical gas medium is

Marco Porta

The Popescu-Gabriel theorem states that each Grothendieck abelian category is a localization of a module category. In this paper, we prove an analogue where Grothendieck abelian categories are replaced by triangulated categories which are well generated (in the sense of Neeman) and algebraic (in the sense of Keller). The role of module categories is played b

Olivera Miskovic, Rodrigo Olea

We revise two regularization mechanisms for Lovelock gravity with AdS asymptotics. The first one corresponds to the Dirichlet counterterm method, where local functionals of the boundary metric are added to the bulk action on top of a Gibbons-Hawking-Myers term that defines the Dirichlet problem in gravity. The generalized Gibbons-Hawking term can be found in

MAGIC Collaboration, J. Albert

We report on the discovery of Very High Energy (VHE) gamma-ray emission from the BL Lacertae object 1ES1011+496. The observation was triggered by an optical outburst in March 2007 and the source was observed with the MAGIC telescope from March to May 2007. Observing for 18.7 hr we find an excess of 6.2 sigma with an integrated flux above 200 GeV of (1.58$\pm

Craig Alan Feinstein

In this brief note, we give a simple information-theoretic proof that 2-state 3-symbol universal Turing machines cannot possibly exist, unless one loosens the definition of &#34;universal&#34;.

F. Natali

In this paper we establish the nonlinear stability of solitary traveling-wave solutions for the Kawahara-KdV equation $$u_t+uu_x+u_{xxx}-γ_1 u_{xxxxx}=0,$$ and the modified Kawahara-KdV equation $$u_t+3u^2u_x+u_{xxx}-γ_2 u_{xxxxx}=0,$$ where $γ_i\in\mathbb{R}$ is a positive number when $i=1,2$. The main approach used to determine the stability of solitary tr

H. van Hees, V. Greco, R. Rapp

We present predictions for the nuclear modification factor and elliptic flow of D and B mesons, as well as of their decay electrons, in semicentral Pb-Pb collisions at the LHC. Heavy quarks are propagated in a Quark-Gluon Plasma using a relativistic Langevin simulation with drag and diffusion coefficients from elastic interactions with light anti-/quarks and

Ernest Barreto, Brian Hunt, Edward Ott, Paul So

The onset of synchronization in networks of networks is investigated. Specifically, we consider networks of interacting phase oscillators in which the set of oscillators is composed of several distinct populations. The oscillators in a given population are heterogeneous in that their natural frequencies are drawn from a given distribution, and each populatio

J. Wildeshaus

We first recall the construction of the Chow motive modelling intersection cohomology of a proper surface and study its fundamental properties. Using Voevodsky&#39;s category of effective geometrical motives, we then study the motive of the exceptional divisor in a non-singular blow-up. If all geometric irreducible components of the divisor are of genus zero

Sandra Martinez

We consider the optimization problem of minimizing $\int_ΩG(|\nabla u|) dx$ in the class of functions $W^{1,G}(Ω)$, with a constrain on the volume of $\{u>0\}$. The conditions on the function $G$ allow for a different behavior at 0 and at $\infty$. We consider a penalization problem, and we prove that for small values of the penalization parameter, the const

H. van Hees, R. Rapp

We predict dilepton invariant-mass spectra for central 5.5 ATeV Pb-Pb collisions at LHC. Hadronic emission in the low-mass region is calculated using in-medium spectral functions of light vector mesons within hadronic many-body theory. In the intermediate-mass region thermal radiation from the Quark-Gluon Plasma, evaluated perturbatively with hard-thermal lo

A. Carrington, E. A. Yelland

In this paper we explore whether the quantum oscillation signals recently observed in ortho-II YBa$_2$Cu$_3$O$_{6.5}$ may be explained by conventional density functional band-structure theory. Our calculations show that the Fermi surface of YBa$_2$Cu$_3$O$_{6.5}$ is extremely sensitive to small shifts in the relative positions of the bands. With rigid band s

J. Piilo, S. Maniscalco, K. Harkonen, K. -A. Suominen

Open quantum systems that interact with structured reservoirs exhibit non-Markovian dynamics. We present a quantum jump method for treating the dynamics of such systems. This approach is a generalization of the standard Monte Carlo Wave Function (MCWF) method for Markovian dynamics. The MCWF method identifies decay rates with jump probabilities and fails for

M. Rizzi, A. Imambekov

We have considered one-dimensional Bose-Fermi mixture with equal densities and unequal masses using numerical density matrix renormalization group (DMRG). For the mass ratio of K-Rb mixture and attraction between bosons and fermions, we determined the phase diagram. For weak boson-boson interactions, there is a direct transition between two-component Lutting

Mike Jarvis, Bhuvnesh Jain

We consider the possible gain in the measurement of lensing shear from imaging data in multiple filters. Galaxy shapes may differ significantly across filters, so that the same galaxy offers multiple samples of the shear. On the other extreme, if galaxy shapes are identical in different filters, one can combine them to improve the signal-to-noise and thus in

Luca Parisi, Marco Bruni, Roy Maartens, Kevin Vandersloot

Loop Quantum Cosmology strongly modifies the high-energy dynamics of Friedman-Robertson-Walker models and removes the big-bang singularity. We investigate how LQC corrections affect the stability properties of the Einstein static universe. In General Relativity, the Einstein static model with positive cosmological constant Lambda is unstable to homogeneous p

A. Matyja, M. Rozanska

We report an observation of the decay $B^0\to D^{*-} τ^+ ν_τ$ in a data sample containing $535\times10^6$ $B\bar{B}$ pairs collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We find a signal with a significance of 5.2 standard deviations and measure the branching fraction $\mathcal{B}(B^0\to D^{*-} τ^+ ν_τ)=(2.02 ^{+0.40}_{-0.

Stephen Tawn

Consider the unit ball, B = D x [0,1], containing n unknotted arcs a_1, ... a_n such that the boundary of each a_i lies in D x {0}. We give a finite presentation for the mapping class group of B fixing the arcs {a_1, ..., a_n} setwise and fixing D x {1} pointwise. This presentation is calculated using the action of this group on a simply-connected complex.

C. Wetterich

The time evolution of a cosmological scalar field can be stopped by an increasing mass of the neutrinos. This leads to a transition from a cosmological scaling solution with dynamical dark energy at early time to a cosmological constant dominated universe at late time. The trigger for the transition is set at the time when the neutrinos become non-relativist

B. I. Shklovskii

We suggest a simple model of disorder in graphene assuming that there are randomly distributed positive and negative centers with equal concentration $N/2$ in the bulk of silicon oxide substrate. We show that at zero gate voltage such disorder creates two-dimensional concentration $n_0 \sim N^{2/3}$ of electrons and holes in graphene. Electrons and holes res