October 2008 arXiv papers — page 29
Showing 2,801–2,900 of 5,765 papers
J. Hirschauer
We present preliminary measurements of time-dependent CP-violation parameters in the decays B0->omegaK0S, B0->eta'K0, B0->pi0K0S, B0->phiK0Spi0, and B0->K+K-K0S, which includes the resonant final states phiK0S and f0(980)K0S. The data sample corresponds to the full BABAAR dataset of 467 million BBbar pairs produced at the PEP-II asymmetric-energy e+e- collid
Thomas Leistner, Pawel Nurowski
We provide an explicit formula for the Fefferman-Graham-ambient metric of an $n$-dimensional conformal $pp$-wave in those cases where it exists. In even dimensions we calculate the obstruction explicitly. Furthermore, we describe all 4-dimensional $pp$-waves that are Bach-flat, and give a large class of Bach-flat examples which are conformally Cotton-flat, b
Stefano Pugnetti, Fabrizio Dolcini, Dario Bercioux, Hermann Grabert
We study a gated quantum wire contacted to source and drain electrodes in the Fabry-Perot regime. The wire is also coupled to a third terminal (tip), and we allow for an asymmetry of the tip tunneling amplitudes of right and left moving electrons. We analyze configurations where the tip acts as an electron injector or as a voltage-probe, and show that the tr
P. Mimica, D. Giannios, M. A. Aloy
(Abridged) We aim to quantitatively understand the dynamical effect and observational signatures of magnetization of the GRB ejecta on the onset of the afterglow. We perform ultrahigh-resolution one-dimensional relativistic MHD simulations of the interaction of a radially expanding, magnetized ejecta with the interstellar medium. The need of ultrahigh numeri
Michal Macek, Pavel Stránský, Pavel Cejnar
A method by Peres is used to draw spectra of the interacting boson model as lattices in the plane of energy versus an arbitrary observable average (or variance). Ordered (disordered) lattices are signatures of regularity (chaos) in both quantum and classical dynamics. The method is also apt to disclose exact or approximate dynamical symmetry.
Victor Yakhot
In this paper, the approach for investigation of asymptotic ($Re\to \infty$) scaling exponents of Eulerian structure functions (J. Schumacher et al, New. J. of Physics {\bf 9}, 89 (2007)) is generalized to studies of Lagrangian structure functions in turbulence. The novel "bridging relation" based on the derived expression for the fluctuating, moment
Enrique Munoz, Jeong-Man Park, Michael W. Deem
We introduce a generalization of the parallel, or Crow-Kimura, and Eigen models of molecular evolution to represent the exchange of genetic information between individuals in a population. We study the effect of different schemes of genetic recombination on the steady-state mean fitness and distribution of individuals in the population, through an analytic f
Energy-momentum tensor for a scalar Casimir apparatus in a weak gravitational field: Neumann conditions
hep-thGeorge M. Napolitano, Giampiero Esposito, Luigi Rosa
We consider a Casimir apparatus consisting of two perfectly conducting parallel plates, subject to the weak gravitational field of the Earth. The aim of this paper is the calculation of the energy-momentum tensor of this system for a free, real massless scalar field satisfying Neumann boundary conditions on the plates. The small gravity acceleration (here co
Borun D. Chowdhury, Samir D. Mathur
In the traditional picture of black holes Hawking radiation is created by pair creation from the vacuum at the horizon. In the fuzzball proposal, individual microstates do not have a horizon with the `vacuum' state in its vicinity. For a special family of non-extremal microstates it was recently found that emission occurs due to pair creation in an ergor
Self-correspondences of K3 surfaces via moduli of sheaves and arithmetic hyperbolic reflection groups
math.AGViacheslav V. Nikulin
An integral hyperbolic lattice is called reflective if its automorphism group is generated by reflections, up to finite index. Since 1981, it is known that their number is essentially finite. We show that K3 surfaces over C with reflective Picard lattices can be characterized in terms of compositions of their self-correspondences via moduli of sheaves with p
Study of moments of event shapes and a determination of \as using \epem annihilation data from \Jade
hep-exChristoph Pahl, Siegfried Bethke, Stefan Kluth, Jochen Schieck
Data from \epem annihilation into hadrons, collected by the \Jade experiment at centre-of-mass energies between 14 GeV and 44 GeV, are used to study moments of event shape distributions. Models with hadronisation parameters tuned to the LEP 1 precision data provide an adequate description of the low energy data studied here. The NLO QCD calculations, however
Joanna Modlawska, Andrzej Grudka
We consider multiple teleportation in the Knill-Laflamme-Milburn (KLM) scheme. We introduce adaptive teleportation, i.e., such that the choice of entangled state used in the next teleportation depends on the results of the measurements performed during the previous teleportations. We show that adaptive teleportation enables an increase in the probability of
Explicit formulas for Laplace transforms of certain functionals of some time inhomogeneous diffusions
math.PRMatyas Barczy, Gyula Pap
We consider a process $(X_t)_{t\in[0,T)}$ given by the SDE $dX_t = αb(t)X_t dt + σ(t) dB_t$, $t\in[0,T)$, with initial condition $X_0=0$, where $T\in(0,\infty]$, $α\in R$, $(B_t)_{t\in[0,T)}$ is a standard Wiener process, $b:[0,T)\to R\setminus\{0\}$ and $σ:[0,T)\to(0,\infty)$ are continuously differentiable functions. Assuming that $b$ and $σ$ satisfy a cer
The Dynamical Behaviour of Test Particles in a Quasi-Spherical Spacetime and the Physical Meaning of Superenergy
gr-qcL. Herrera, J. Carot, N. Bolivar, E. Lazo
We calculate the instantaneous proper radial acceleration of test particles (as measured by a locally defined Lorentzian observer) in a Weyl spacetime, close to the horizon. As expected from the Israel theorem, there appear some bifurcations with respect to the spherically symmetric case (Schwarzschild), which are explained in terms of the behaviour of the s
Mazhar Ali, G. Alber, A. R. P. Rau
Manipulation of sudden death of entanglement (ESD) of two qubits interacting with statistically uncorrelated thermal reservoirs is investigated. It is shown that for initially prepared X-states of the two qubits a simple (necessary and sufficient) criterion for ESD can be derived with the help of the Peres-Horodecki criterion. This criterion implies that, in
Deconfinement phase transition in N=4 super Yang-Mills theory on RxS^3 from supersymmetric matrix quantum mechanics
hep-thGoro Ishiki, Sang-Woo Kim, Jun Nishimura, Asato Tsuchiya
We test the recent claim that supersymmetric matrix quantum mechanics with mass deformation preserving maximal supersymmetry can be used to study N=4 super Yang-Mills theory on RxS^3 in the planar limit. When the mass parameter is large, we can integrate out all the massive fluctuations around a particular classical solution, which corresponds to RxS^3. The
Prompt GeV Emission from Residual Collisions in GRB Outflows: Evidence from Fermi Observations of GRB 080916c
astro-phZhuo Li
The gamma-rays from gamma-ray bursts (GRBs) are believed to be produced by internal shocks driven by small timescale, ~1 ms, variation in the GRB outflows, and a pair-production spectral cutoff is generally expected around the GeV range. However, the observed optical flashes accompanying GRBs suggest that the delayed residual collisions due to large timescal
E. N. Thompson
We present the potential of the ATLAS detector to discover new massive gauge bosons in their leptonic decay channels: W' -> l nu_l and Z' -> l+ l-. Emphasis is placed on early data-taking at the LHC with low luminosity (up to 1 fb^-1).
Alexander C. R. Belton
It is shown how to construct quantum random walks with particles in an arbitrary faithful normal state. A convergence theorem is obtained for such walks, which demonstrates a thermalisation effect: the limit cocycle obeys a quantum stochastic differential equation without gauge terms. Examples are presented which generalise that of Attal and Joye (2007, J. F
Andrew S. Dancer, McKenzie Y. Wang
We produce new examples of non-Kähler complete expanding gradient Ricci solitons on trivial vector bundles over a product of Einstein manifolds with positive scalar curvature.
Latham Boyle, Paul J. Steinhardt
We note that the essential idea of inflation, that the universe underwent a brief period of accelerated expansion followed by a long period of decelerated expansion, can be encapsulated in a "closure condition" which relates the amount of accelerated expansion during inflation to the amount of decelerated expansion afterward. We present a protocol fo
Andris Ambainis, Debbie Leung, Laura Mancinska, Maris Ozols
We consider a communication method, where the sender encodes n classical bits into 1 qubit and sends it to the receiver who performs a certain measurement depending on which of the initial bits must be recovered. This procedure is called (n,1,p) quantum random access code (QRAC) where p > 1/2 is its success probability. It is known that (2,1,0.85) and (3,1,0
Rainer Beck
The strength of the total magnetic field in our Milky Way from radio Zeeman and synchrotron measurements is about 6 muG near the Sun and several mG in dense clouds, pulsar wind nebulae, and filaments near the Galactic Center. Diffuse polarized radio emission and Faraday rotation of the polarized emission from pulsars and background sources show many small-sc
Sylvie Corteel, Lauren Williams
The results of this paper have been subsumed by those of our new paper arXiv:0910.1858
Olivier Durieu, Dalibor Volny
In this paper, we are interested in the limit theorem question for sums of indicator functions. We show that in every aperiodic dynamical system, for every increasing sequence $(a_n)_{n\in\N}\subset\R_+$ such that $a_n\nearrow\infty$ and $\frac{a_n}{n}\to 0$ as $n\to\infty$, there exists a measurable set $A$ such that the sequence of the distributions of the
Youichi Yanase, Naoyuki Yorozu
Motivated by the discovery of superconductivity in boron-doped (B-doped) diamond, we investigate the localization and superconductivity in heavily doped semiconductors. The competition between Anderson localization and s-wave superconductivity is investigated from the microscopic point of view. The effect of microscopic inhomogeneity and the thermal fluctuat
J. -F. Arguin
The ATLAS pixel detector is a high precision silicon tracking device located closest to the LHC interaction point. It belongs to the first generation of its kind in a hadron collider experiment. It will provide crucial pattern recognition information and will largely determine the ability of ATLAS to precisely track particle trajectories and find secondary v
Enhancement of the superconducting transition temperature in cuprate heterostructures
cond-mat.supr-conLilach Goren, Ehud Altman
Is it possible to increase Tc by constructing cuprate heterostructures, which combine the high pairing energy of underdoped layers with the large carrier density of proximate overdoped layers? We investigate this question within a model bilayer system using an effective theory of the doped Mott insulator. Interestingly, the question hinges on the fundamental
Swagato Mukherjee
We present lattice QCD results for the screening masses of light mesons and charmonia. The lattice computations were performed with 2+1 flavors of improved staggered quarks using quark masses which correspond to realistic pion and kaon masses at zero temperature. For the light quark sector we have found that the screening masses in the pseudo-scalar and the
Tatjana Tchumatchenko, Aleksey Malyshev, Theo Geisel, Maxim Volgushev
We study how threshold model neurons transfer temporal and interneuronal input correlations to correlations of spikes. We find that the low common input regime is governed by firing rate dependent spike correlations which are sensitive to the detailed structure of input correlation functions. In the high common input regime the spike correlations are insensi
R. Fiore, L. Jenkovszky, R. Orava, E. Predazzi
The following effects in the nearly forward ("soft") region of the LHC are proposed to be investigated: 1) At small |t| the fine structure of the cone (Pomeron) shouldbe scrutinized: a) a break of the cone near $t\approx - 0.1 ~ GeV$^2, due to the two-pion threshold, and required by t-channel unitarity, is expected, and b) possible small-period oscil
Ugo Dal Lago, Luca Roversi, Luca Vercelli
Pure, or type-free, Linear Logic proof nets are Turing complete once cut-elimination is considered as computation. We introduce modal impredicativity as a new form of impredicativity causing the complexity of cut-elimination to be problematic from a complexity point of view. Modal impredicativity occurs when, during reduction, the conclusion of a residual of
Dust Extinction in High-z Galaxies with GRB Afterglow Spectroscopy - The 2175Å Feature at z=2.45
astro-phÁ. Elíasdóttir, J. P. U. Fynbo, J. Hjorth, C. Ledoux
We report the clear detection of the 2175A dust absorption feature in the optical afterglow spectrum of the gamma-ray burst (GRB) GRB070802 at a redshift of z=2.45. This is the highest redshift for a detected 2175A dust bump to date, and it is the first clear detection of the 2175A bump in a GRB host galaxy, while several tens of optical afterglow spectra wi
Density matrix renormalization group study of a quantum impurity model with Landau-Zener time-dependent Hamiltonian
cond-mat.str-elCheng Guo, Andreas Weichselbaum, Stefan Kehrein, Tao Xiang
We use the adaptive time-dependent density matrix renormalization group method (t-DMRG) to study the nonequilibrium dynamics of a benchmark quantum impurity system which has a time-dependent Hamiltonian. This model is a resonant-level model, obtained by a mapping from a certain Ohmic spin-boson model describing the dissipative Landau-Zener transition. We map
Igor M. Pavlichenkov
The theoretical aspects of spin-rotation coupling are presented. The approach is based on the general covariance principle. It is shown that the gyrogravitational ratio of the bare spin-1/2 and the spin-1 particles is equal unity. That is why spin couples with rotation as an ordinary angular momentum. This result is the rigorous substantiation of the crankin
Pierre-Emmanuel Caprace, Alexander Lytchak
We show that any filtering family of closed convex subsets of a finite-dimensional CAT(0) space $X$ has a non-empty intersection in the visual bordification $ \bar{X} = X \cup \partial X$. Using this fact, several results known for proper CAT(0) spaces may be extended to finite-dimensional spaces, including the existence of canonical fixed points at infinity
E. A. J. F. Peters
A careful derivation of the generalized Langevin equation using "Zwanzig flavor" projection operator formalism is presented. We provide arguments why this formalism has better properties compared to alternative projection-operator formalisms for deriving non-equilibrium, non-thermodynamic-limit, equations. The two main ingredients in the derivation a
Mubasher Jamil
We here investigate the model of interacting dark energy in the context of five dimensional brane cosmology. The effective equations of state of dark energy are evaluated for various choices of the variable time dependent cosmological constant. We have found that the interacting dark energy obeys the phantom divide/crossing scenario in this generalized model
B. Gendre, S. Pelisson, M. Boer, S. Basa
Clustering in the luminosity of the afterglows of gamma-ray burst has been reported in the optical and X-ray. We investigate the possibility that a clustering in the luminosity of the afterglows of gamma-ray burst exists in near infrared (J, H, K bands). We use observations of events occurring from 1997 to the end of 2007. We correct the gamma-ray burst afte
Ivan Nourdin, Giovanni Peccati, Gesine Reinert
We compute explicit bounds in the Gaussian approximation of functionals of infinite Rademacher sequences. Our tools involve Stein's method, as well as the use of appropriate discrete Malliavin operators. Although our approach does not require the classical use of exchangeable pairs, we employ a chaos expansion in order to construct an explicit exchangeab
Robert D. Groot, Simeon D. Stoyanov
A simulation model is presented, comprising elastic spheres with a short range attraction. Besides conservative forces, radial- and shear friction, and radial noise are added. The model can be used to simulate colloids, granular solids and powders, and the parameters may be related to experimental systems via the range of attraction and the adhesion energy.
Giuseppe Finocchiaro
We review the experimental status of the angles of the Unitarity Triangle of the CKM matrix, as measured by the BABAR and Belle experiments.
E. Kankare, S. Mattila, S. Ryder, M. -A. Perez-Torres
We report the discovery of a confirmed supernova (SN) and a supernova-candidate in near-infrared images from the ALTAIR/NIRI adaptive optics system on the Gemini-North Telescope and NICMOS on the Hubble Space Telescope. The Gemini images were obtained as part of a near-infrared K-band search for highly-obscured SNe in the nuclear regions of luminous infrared
Libby Heaney, Janet Anders
Experiments showing the violation of Bell inequalities have formed our belief that the world at its smallest is genuinely non-local. While many non-locality experiments use the first quantised picture, the physics of fields of indistinguishable particles, such as bosonic gases, is captured most conveniently by second quantisation. This implies the possibilit
Emeric Deutsch, Elisa Pergola, Renzo Pinzani
In this paper we establish six bijections between a particular class of polyominoes, called deco polyominoes, enumerated according to their directed height by n!, and permutations. Each of these bijections allows us to establish different correspondences between classical statistics on deco polyominoes and on permutations.
Scaling and chiral extrapolation of pion mass and decay constant with maximally twisted mass QCD
hep-latP. Dimopoulos, R. Frezzotti, G. Herdoiza, K. Jansen
We present an update of the results for pion mass and pion decay constant as obtained by the ETM collaboration in large scale simulations with maximally twisted mass fermions and two mass degenerate flavours of light quarks. We discuss the continuum, chiral and infinite volume extrapolation of these quantities as well as the extraction of low energy constant
Alberto Belloni
The ATLAS experiment at the Large Hadron Collider (LHC) at CERN is currently waiting to record the first collision data in spring 2009. Its muon spectrometer is designed to achieve a momentum resolution of 10% pT(mu) = 1 TeV/c. The spectrometer consists of a system of three superconducting air-core toroid magnets and is instrumented with three layers of Moni
Higher dimensional bright solitons and their collisions in multicomponent long wave-short wave system
nlin.SIT. Kanna, M. Vijayajayanthi, K. Sakkaravarthi, M. Lakshmanan
Bright plane soliton solutions of an integrable (2+1) dimensional ($n+1$)-wave system are obtained by applying Hirota's bilinearization method. First, the soliton solutions of a 3-wave system consisting of two short wave components and one long wave component are found and then the results are generalized to the corresponding integrable ($n+1$)-wave syst
A. R. Gover, A. Shaukat, A. Waldron
Deser and Nepomechie established a relationship between masslessness and rigid conformal invariance by coupling to a background metric and demanding local Weyl invariance, a method which applies neither to massive theories nor theories which rely upon gauge invariances for masslessness. We extend this method to describe massive and gauge invariant theories u
Daniel Burgarth, Koji Maruyama, Franco Nori
Quantum control requires full knowledge of the system many-body Hamiltonian. In many cases this information is not directly available due to restricted access to the system. Here we show how to indirectly estimate all the coupling strengths in a spin chain by measuring one spin at the end of the chain. We also discuss the efficiency of this "quantum inve
The Schrodinger-Chetaev Equation in Bohmian Quantum Mechanics and Diffusion Mechanism for Alpha Decay, Cluster Radioactivity and Spontaneous Fission
quant-phV. D. Rusov, S. Cht. Mavrodiev, M. A. Deliyergiyev
In the framework of Bohmian quantum mechanics supplemented with the Chetaev theorem on stable trajectories in dynamics in the presence of dissipative forces we have shown the possibility of the classical (without tunneling) universal description of radioactive decay of heavy nuclei, in which under certain conditions so called noise-induced transition is gene
Jean-Marc Couveignes, Tony Ezome, Reynald Lercier
We define the ring of elliptic periods modulo an integer $n$ and give an elliptic version of the AKS primality criterion.
Konstantin Y. Bliokh, Ilya V. Shadrivov, Yuri S. Kivshar
We study, analytically and numerically, reflection and transmission of an arbitrarily polarized vortex beam on an interface separating two dielectric media and derive general expressions for linear and angular Goos-Hanchen and Imbert-Fedorov shifts. We predict a novel vortex-induced Goos-Hanchen shift, and also reveal direct connection between the spin-induc
Victor Kozyakin
The famous Gelfand formula $ρ(A)= \limsup_{n\to\infty}\|A^{n}\|^{1/n}$ for the spectral radius of a matrix is of great importance in various mathematical constructions. Unfortunately, the range of applicability of this formula is substantially restricted by a lack of estimates for the rate of convergence of the quantities $\|A^{n}\|^{1/n}$ to $ρ(A)$. In the
I. L. Buchbinder, A. V. Galajinsky
We generalize the unconstrained description of free massless higher spin fields previously developed in [Nucl.Phys. B 779 (2007) 155] to the case of free massive higher spin fields in a flat space of arbitrary dimension. The Lagrangian is given in an easy-to-handle form for an arbitrary value of spin. It is local, free from higher derivative terms, and invol
Prasad Subramanian, H. M. Antia, S. R. Dugad, U. D. Goswami
We seek to estimate the average level of MHD turbulence near coronal mass ejection (CME) fronts as they propagate from the Sun to the Earth. We examine the cosmic ray data from the GRAPES-3 tracking muon telescope at Ooty, together with the data from other sources for three well observed Forbush decrease events. Each of these events are associated with front
Mihailo R. Jovanović, Satish Kumar
Nonmodal amplification of stochastic disturbances in elasticity-dominated channel flows of Oldroyd-B fluids is analyzed in this work. For streamwise-constant flows with high elasticity numbers $μ$ and finite Weissenberg numbers $We$, we show that the linearized dynamics can be decomposed into slow and fast subsystems, and establish analytically that the stea
Solving polynomial differential equations by transforming them to linear functional-differential equations
math.RAJohn Michael Nahay
We present a new approach to solving polynomial ordinary differential equations by transforming them to linear functional equations and then solving the linear functional equations. We will focus most of our attention upon the first-order Abel differential equation with two nonlinear terms in order to demonstrate in as much detail as possible the computation
Michael E. Zieve
Carlitz proved that, for any prime power q other than 2, the group of all permutations of the finite field F_q is generated by the permutations induced by degree-one polynomials and x^{q-2}. His proof relies on a remarkable polynomial which appears to have been found by magic. We show here that no magic is required: there is a straightforward way to produce
Yao-Hui Yang
We introduce the Blume-Emery-Griffiths (BEG) model in a social networks to describe the three-state dynamics of opinion formation. It shows that the probability distribution function of the time series of opinion is a Gaussian-like distribution. We also study the response of BEG model to the external periodic perturbation. One can observe that both the inter
P. M. Leung, T. C. Ralph, William J. Munro, Kae Nemoto
According to idealized models, a strong Kerr non-linearity may be used to build optical quantum gates for optical quantum information processing by inducing conditional phase shifts on quantum states. Recently, Shapiro (PRA 73, 062305 (2006)) argued that for a Kerr medium with non-instantaneous but fast response, essentially no phase shift is induced on two-
Hideyoshi Arakida
We investigated the influence of dark matter on light propagation in the solar system. We assumed the spherical symmetry of spacetime and derived the approximate solution of the Einstein equation, which consists of the gravitational attractions caused by the central celestial body, i.e. the Sun, and the dark matter surrounding it. We expressed the dark matte
Classical solutions for the Lorentz-violating and CPT-even term of the Standard Model Extension
hep-thR. Casana, M. M. Ferreira, C. E. H. Santos
In this work, we calculate the classical solutions for the electrodynamics stemming from the Lorentz-violating (LV) and CPT-even term of the Standard Model Extension. The solutions for point-like and extended charges are obtained from the wave equations by means of the Green method. A dipolar expansion is written for the field strengths. It is explicitly sho
Standard random walks and trapping on the Koch network with scale-free behavior and small-world effect
physics.soc-phZhongzhi Zhang, Shuigeng Zhou, Wenlei Xie, Lichao Chen
A vast variety of real-life networks display the ubiquitous presence of scale-free phenomenon and small-world effect, both of which play a significant role in the dynamical processes running on networks. Although various dynamical processes have been investigated in scale-free small-world networks, analytical research about random walks on such networks is m
L. N. Granda, A. Oliveros
We propose an infrared cut-off for the holographic the dark-energy, which besides the square of the Hubble scale also contains the time derivative of the Hubble scale. This avoids the problem of causality which appears using the event horizon area as the cut-off, and solves the coincidence problem.
Ivan Junier, Felix Ritort
We review theoretical approaches, experiments and numerical simulations that have been recently proposed to investigate the folding problem in single-domain proteins. From a theoretical point of view, we emphasize the energy landscape approach. As far as experiments are concerned, we focus on the recent development of single-molecule techniques. In particula
Torsten Dahms
This work presents measurements of electron-positron pairs from p+p collisions at sqrt(s) = 200 GeV collected during the 2005 RHIC run and compares them to results from Au+Au collisions at sqrt(s_NN) = 200 GeV taken in 2004 with the PHENIX detector. The invariant mass distribution of e+e- pairs in p+p is consistent with the expected contributions from Dalitz
Spencer R. Klein
The strong electromagnetic fields carried by relativistic highly charged ions make heavy-ion colliders attractive places to study photonuclear interactions and two-photon interactions. At RHIC, three experiments have studied coherent photoproduction of $ρ^0$, 4$π$, $J/ψ$, $e^+e^-$ pairs, and $e^+e^-$ pairs where the electron is bound to one of the incident n
Mostafa Bendahmane, Raimund Bürger, Ricardo Ruiz Baier
This paper presents a finite-volume method, together with fully adaptive multi-resolution scheme to obtain spatial adaptation, and a Runge-Kutta-Fehlberg scheme with a local time-varying step to obtain temporal adaptation, to solve numerically the known "bidominio" equations that model the electrical activity of the tissue in the myocardium. Two simp
Atoms in the Surf: Molecular Dynamics Simulation of the Kelvin-Helmholtz Instability using 9 Billion Atoms
cond-mat.mtrl-sciD. F. Richards, L. D. Krauss, W. H. Cabot, K. J. Caspersen
We present a fluid dynamics video showing the results of a 9-billion atom molecular dynamics simulation of complex fluid flow in molten copper and aluminum. Starting with an atomically flat interface, a shear is imposed along the copper-aluminum interface and random atomic fluctuations seed the formation of vortices. These vortices grow due to the Kelvin-Hel
S Keller, A Marotta, Z Papp
Three-body resonances in atomic systems are calculated as complex-energy solutions of Faddeev-type integral equations. The homogeneous Faddeev-Merkuriev integral equations are solved by approximating the potential terms in a Coulomb-Sturmian basis. The Coulomb-Sturmian matrix elements of the three-body Coulomb Green's operator has been calculated as a co
Costas J. Efthimiou
I bring to the attention of the physics community the non-existence of a Putnam Physics Competition in North America despite the fact that the Putnam Mathematical Competition has been well known and highly successful for 70 years.
J. Wosiek
We review a performance of Fock space methods in calculating spectra of a range of supersymmetric models with gauge symmetry. Examples include: a) SU(2) Supersymmetric Yang Mills Quantum Mechanics in four euclidean dimensions, b) Quantum Mechanics of one fermion and one boson with infinite number of colours, and c) planar 1+1 dimensional Yang Mills theories
T. Banakh, L. Zdomskyy
It is shown that each pseudonorm defined on a subgroup $H$ of an abelian group $G$ can be extended to a pseudonorm on $G$ such that the densities of the obtained pseudometrizable topological groups coincide. We derive from this that any Hausdorff $ω$-bounded group topology on $H$ can be extended to a Hausdorff $ω$-bounded group topology on $G$. In its turn t
O. Costin, M. Huang
We develop a local theory of lacunary Dirichlet series of the form $\sum\limits_{k=1}^{\infty}c_k\exp(-zg(k)), \Re(z)>0$ as $z$ approaches the boundary $i\RR$, under the assumption $g'\to\infty$ and further assumptions on $c_k$. These series occur in many applications in Fourier analysis, infinite order differential operators, number theory and holomorph
T. Banakh, O. Hryniv
Let $K$ be a complete quasivariety of topological inverse Clifford semigroups, containing all topological semilattices. It is shown that the free topological inverse semigroup $F(X,K)$ of $X$ in the class $K$ is an $R^\infty$-manifold if and only if $X$ has no isolated points and $F(X,K)$ is a retract of an $R^\infty$-manifold. We derive from this that for a
(Metrically) quarter-stratifiable spaces and their applications in the theory of separately continuous functions
math.GNTaras Banakh
We introduce and study (metrically) quarter-stratifiable spaces and then apply them to generalize Rudin and Kuratowski-Montgomery theorems about the Baire and Borel complexity of separately continuous functions.
Joseph Y. Halpern, Rafael Pass
For some well-known games, such as the Traveler's Dilemma or the Centipede Game, traditional game-theoretic solution concepts--and most notably Nash equilibrium--predict outcomes that are not consistent with empirical observations. In this paper, we introduce a new solution concept, iterated regret minimization, which exhibits the same qualitative behavi
T. O. Banakh, V. I. Bogachev, A. V. Kolesnikov
In this paper we introduce and study so-called $k^*$-metrizable spaces forming a new class of generalized metric spaces, and display various applications of such spaces in topological algebra, functional analysis, and measure theory. By definition, a Hausdorff topological space $X$ is $k^*$-metrizable if $X$ is the image of a metrizable space $M$ under a con
Joshua Cooper, Stephen Fenner, Semmy Purewal
A $d$-dimensional grid is a set of the form $R = [a_1] \times ... \times [a_d]$. A $d$-dimensional box is a set of the form $\{b_1,c_1\} \times ... \times \{b_d,c_d\}$. When a grid is $c$-colored, must it admit a monochromatic box? If so, we say that $R$ is $c$-guaranteed. This question is a relaxation of one attack on bounding the van der Waerden numbers, a
Andrzej M. Frydryszak
We address the question of description of qubit system in a formalism based on the nilpotent commuting variables. In this formalism qubits exhibit properties of composite objects being subject of the Pauli exclusion principle, but otherwise behaving boson-like. They are not fundamental particles. In such an approach the classical limit yields the nilpotent m
J. D. T. Smith, Lawrence Rudnick, Tracey Delaney, Jeonghee Rho
We present the global distribution of fine structure infrared line emission in the Cassiopeia A supernova remnant using data from the Spitzer Space Telescope's Infrared Spectrograph. We identify emission from ejecta materials in the interior, prior to their encounter with the reverse shock, as well as from the post-shock bright ring. The global electron
David Eichler, Dafne Guetta, Hadar Manis
It is noted that X-ray tails (XRTs) of short, hard $γ$-ray bursts (SHBs) are similar to X-ray flashes (XRFs). We suggest a universal central engine hypothesis, as a way of accounting for this curiosity, in which SHBs differ from long $γ$-ray bursts (GRBs) in prompt emission because of the differences in the host star and attendant differences in the environm
Doron Chelouche, Raul Rabadan, Sergey Pavlov, Francisco Castejon
We propose a new method to search for light (pseudo-)scalar particles in the spectra of compact astrophysical objects such as magnetars, pulsars, and quasars. On accounts of compact astrophysical objects having intense magnetic fields extending over large volumes, they provide good conditions for efficient photon-particle oscillations via the Primakoff proce
Compact groups in theory and practice - II. Comparing the observed and predicted nature of galaxies in compact groups
astro-phCrystal M. Brasseur, Alan W. McConnachie, Sara L. Ellison, David R. Patton
We examine the properties of galaxies in compact groups identified in a mock galaxy catalogue based upon the Millennium Run simulation. The overall properties of groups identified in projection are in general agreement with the best available observational constraints. However, only ~30% of these simulated groups are found to be truly compact in 3 dimensions
David Eichler, Hadar Manis
A quantitative theory of spectral lags for $γ$-ray bursts (GRBs) is given. The underlying hypothesis is that GRB subpulses are photons that are scattered into our line of sight by local concentrations of baryons that are accelerated by radiation pressure. For primary spectra that are power laws with exponential cutoffs, the width of the pulse and its fast ri
Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Nairn Baliber
We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 13 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ~10^6-10^7 M_sun. We present here the first results from this project -- the mass of the central black hole in
Doron Chelouche, Eduardo I. Guendelman
We show that, by studying the arrival times of radio pulses from highly-magnetized pulsars, it may be possible to detect light spin-0 bosons (such as axions and axion-like particles) with a much greater sensitivity, over a broad particle mass range than is currently reachable by terrestrial experiments and indirect astrophysical bounds. In particular, we stu
Testing Mass Loss in Large Magellanic Cloud Cepheids using Infrared and Optical Observations
astro-phHilding R. Neilson, Chow-Choong Ngeow, Shashi M. Kanbur, John B. Lester
It has been claimed that Period-Luminosity relations derived from infrared observations of Large Magellanic Cloud (LMC) Cepheids are less dependent on the metallicity of the Cepheids. In this work, infrared observations of LMC Cepheids from the SAGE survey are combined with OGLE II optical observation to model and predict mass-loss rates. The mass-loss rates
Langevin approach for the dynamics of the contact process on annealed scale-free networks
cond-mat.dis-nnMarian Boguna, Claudio Castellano, Romualdo Pastor-Satorras
We study the dynamics of the contact-process, one of the simplest nonequilibrium stochastic processes, taking place on a scale-free network. We consider the network topology as annealed, i.e. all links are rewired at each microscopic time step, so that no dynamical correlation can build up. This is a practical implementation of the absence of correlations as
Brian Dudley, Christopher Kolda
The question of whether neutrino masses are Dirac or Majorana is one of the most important, and most difficult, questions remaining in the neutrino sector. Searches for neutrinoless double beta-decay may help to resolve this question, but are also sensitive to new, higher dimension Delta L=2 operators. In this paper we place two phenomenological constraints
C. Karoff
We recently presented evidence of a strong correlation between the energy in the high-frequency part of the acoustic spectrum of the Sun and the solar X-ray flux Karoff & Kjeldsen (2008). The discovery indicates that flares drive global oscillations in the Sun in the same way that the entire Earth is set ringing for several weeks after a major earthquake, su
S. Garcia-Burillo, F. Combes, A. Usero, J. Gracia-Carpio
The study of the content, distribution and kinematics of interstellar gas is a key to understand the origin and maintenance of both starburst and nuclear (AGN) activity in galaxies. The processes involved in AGN fueling encompass a wide range of scales, both spatial and temporal, which have to be studied. Probing the gas flow from the outer disk down to the
Craig A. Nolder, John Ryan
We introduce non-linear Dirac operators in $\mathbb{R}^{n}$ associated to the $p$-harmonic equation and we extend to other contexts including spin manifolds and the sphere.
Michael J. Barlow
I review the prospects for studies of the advanced evolutionary stages of low-, intermediate- and high-mass stars by the JWST and concurrent facilities, with particular emphasis on how they may help elucidate the dominant contributors to the interstellar dust component of galaxies. Observations extending from the mid-infrared to the submillimeter can help qu
Jan Verschelde
In numerical algebraic geometry witness sets are numerical representations of positive dimensional solution sets of polynomial systems. Considering the asymptotics of witness sets we propose certificates for algebraic curves. These certificates are the leading terms of a Puiseux series expansion of the curve starting at infinity. The vector of powers of the
Christian Houdré, Trevis J. Litherland
Let $(X_n)_{n \ge 0}$ be an irreducible, aperiodic, homogeneous Markov chain, with state space an ordered finite alphabet of size $m$. Using combinatorial constructions and weak invariance principles, we obtain the limiting shape of the associated Young tableau as a multidimensional Brownian functional. Since the length of the top row of the Young tableau is
Ingo Kreykenbohm, Joern Wilms, Peter Kretschmar, Jose Miguel Torrejon
We investigate the spectral and temporal behavior of the high mass X-ray binary Vela X-1 during a phase of high activity, with special focus on the observed giant flares and off states. INTEGRAL observed Vela X-1 in a long almost uninterrupted observation for two weeks in 2003 Nov/Dec. The data were analyzed with OSA 7.0 and FTOOLS 6.2. We derive the pulse p
J. Ye, S. Tanveer
Using a vortex sheet method we prove global existence of a near circular initial bubble in a Hele-Shaw cell with surface tension and generally finite nonzero viscosity ratio between fluids inside and outside the bubble. The circular shape is shown to be asymptotically stable for all sufficiently smooth small perturbation. The initial condition in this case,
M. Dajczer, J. H. de Lira
We prove an existence result for helicoidal graphs with prescribed mean curvature in a large class of warped product spaces which comprises space forms.