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March 2009 arXiv papers — page 40

Showing 3,9014,000 of 5,470 papers

  1. Raquel Salmeron

    Star formation is thought to be triggered by the gravitational collapse of the dense cores of molecular clouds. Angular momentum conservation during the collapse results in the progressive increase of the centrifugal force, which eventually halts the inflow of material and leads to the development of a central mass surrounded by a disc. In the presence of an

  2. S. Ramstedt, F. L. Schoeier, H. Olofsson

    The main aim is to derive reliable mass-loss rates and circumstellar SiO abundances for a sample of 40 S-type AGB stars based on new multi-transitional CO and SiO radio line observations. In addition, the results are compared to previous results for M-type AGB stars and carbon stars to look for trends with chemical type. The circumstellar envelopes are assum

  3. F. J. Garcia de Abajo

    This colloquium analyzes the interaction of light with two-dimensional periodic arrays of particles and holes. The enhanced optical transmission observed in the latter and the presence of surface modes in patterned metal surfaces are thoroughly discussed. A review of the most significant discoveries in this area is presented first. A simple tutorial model is

  4. Jenny Clark, Jui-Fen Chang, Frank C. Spano, Richard H. Friend

    We analyze the linear absorption spectrum of regioregular poly(3-hexylthiophene) films spun from a variety of solvents to probe directly the film microstructure and how it depends on processing conditions. We estimate the exciton bandwidth and the percentage of the film composed of aggregates quantitatively using a weakly interacting H-aggregate model. This

  5. F. J. Garcia de Abajo

    This review discusses how low-energy, valence excitations created by swift electrons can render information on the optical response of structured materials with unmatched spatial resolution. Electron microscopes are capable of focusing electron beams on sub-nanometer spots and probing the target response either by analyzing electron energy losses or by detec

  6. Paolo M. Bonifacio, Charles H. -T. Wang, J. Tito Mendonca, Robert Bingham

    We investigate the dephasing suffered by a nonrelativistic quantum particle within a conformally fluctuating spacetime geometry. Starting from a minimally coupled massive Klein-Gordon field, the low velocity limit yields an effective Schrodinger equation where the wave function couples to gravity through an effective nonlinear potential induced by the confor

  7. Ivan Agullo, Enrique F. Borja, Jacobo Diaz-Polo

    Motivated by the analogy proposed by Witten between Chern-Simons and Conformal Field Theories, we explore an alternative way of computing the entropy of a black hole starting from the isolated horizon framework in Loop Quantum Gravity. The consistency of the result opens a window for the interplay between Conformal Field Theory and the description of black h

  8. Veronique Bernard, Micaela Oertel, Emilie Passemar, Jan Stern

    An accurate low-energy dispersive parametrization of the scalar Kpi form factor was constructed some time ago in terms of a single parameter guided by the Callan-Treiman low-energy theorem. A similar twice subtracted dispersive parametrization for the vector Kpi form factor will be investigated here. The robustness of the parametrization of these two form fa

  9. Bruno Uchoa, A. H. Castro Neto

    Comment on "BCS superconductivity of Dirac fermions in graphene layers" by N. B. Kopnin and E. B. Sonin [arXiv:0803.3772; Phys. Rev. Lett. 100, 246808 (2008)].

  10. K. Zahnle, M. S. Marley, R. S. Freedman, K. Lodders

    We develop a new 1D photochemical kinetics code to address stratospheric chemistry and stratospheric heating in hot Jupiters. Here we address optically active S-containing species and CO2 at 1200 < T < 2000 K. HS (mercapto) and S2 are highly reactive species that are generated photochemically and thermochemically from H2S with peak abundances between 1-10 mb

  11. S. Boixo, E. Knill, R. D. Somma

    A computation in adiabatic quantum computing is implemented by traversing a path of nondegenerate eigenstates of a continuous family of Hamiltonians. We introduce a method that traverses a discretized form of the path: At each step we apply the instantaneous Hamiltonian for a random time. The resulting decoherence approximates a projective measurement onto t

  12. Kathryn Hess, Andrew Tonks

    We prove that for any 1-reduced simplicial set X, Adams' cobar construction, \Omega CX, on the normalised chain complex of X is naturally a strong deformation retract of the normalised chains CGX on the Kan loop group GX, opening up the possibility of applying the tools of homological algebra to transfering perturbations of algebraic structure from the latte

  13. Jozsef Z. Farkas, Peter Hinow

    In this work we introduce and analyze a linear size-structured population model with infinite states-at-birth. We model the dynamics of a population in which individuals have two distinct life-stages: an "active" phase when individuals grow, reproduce and die and a second "resting" phase when individuals only grow. Transition between these two phases depends

  14. Alexei Kolezhuk

    I show that in low dimensions the interactions in dilute Bose mixtures are strongly renormalized, which leads to a considerable change of stability conditions compared to the mean-field results valid in the high-density regime. Estimates are given for the two-component Bose-Hubbard model and for the Rb(87)-K(41) mixture.

  15. Rafael I. Nepomechie

    We investigate the open spin chain describing the scalar sector of the Y=0 giant graviton brane at weak coupling. We provide a direct proof of integrability in the SU(2) and SU(3) sectors by constructing the transfer matrices. We determine the eigenvalues of these transfer matrices in terms of roots of the corresponding Bethe ansatz equations (BAEs). Based o

  16. Kamil Bradler

    We introduce an infinite sequence of quantum channels for which the Holevo capacity is additive. The channel series is closely related to the quantum channels arising from universal quantum cloning machines. The additivity proof is motivated by a special property the studied channels enjoy: the property of conjugate degradability. As a consequence of the ann

  17. K. Rajaratnam

    The credit crisis of 2007 and 2008 has thrown much focus on the models used to price mortgage backed securities. Many institutions have relied heavily on the credit ratings provided by credit agency. The relationships between management of credit agencies and debt issuers may have resulted in conflict of interest when pricing these securities which has lead

  18. P. Rabl, C. Genes, K. Hammerer, M. Aspelmeyer

    We present a detailed theoretical discussion of the effects of ubiquitous laser noise on cooling and the coherent dynamics in opto-mechanical systems. Phase fluctuations of the driving laser induce modulations of the linearized opto-mechanical coupling as well as a fluctuating force on the mirror due to variations of the mean cavity intensity. We first evalu

  19. Thorsten Naab, Peter H. Johansson, Jeremiah P. Ostriker

    Using a high resolution hydrodynamical cosmological simulation of the formation of a massive spheroidal galaxy we show that elliptical galaxies can be very compact and massive at high redshift in agreement with recent observations. Accretion of stripped in-falling stellar material increases the size of the system with time and the central concentration is re

  20. A. Yang, M. Steger, T. Sekiguchi, M. L. W. Thewalt

    We demonstrate a method which can hyperpolarize both the electron and nuclear spins of 31P donors in Si at low field, where both would be essentially unpolarized in equilibrium. It is based on the selective ionization of donors in a specific hyperfine state by optically pumping donor bound exciton hyperfine transitions, which can be spectrally resolved in 28

  21. Tim Austin

    We offer a new proof of Furstenberg and Katznelson&#39;s density version of the Hales-Jewett Theorem: For any $δ> 0$ there is some $N_0 \geq 1$ such that whenever $A \subseteq [k]^N$ with $N \geq N_0$ and $|A|\geq δk^N$, $A$ contains a \textbf{combinatorial line}: that is, for some $I \subseteq [N]$ nonempty and $w_0 \in [k]^{[N]\setminus I}$ we have A \sups

  22. R. Sutarto, S. G. Altendorf, B. Coloru, M. Moretti Sala

    We have succeeded in preparing high-quality Gd-doped single-crystalline EuO films. Using Eu-distillation-assisted molecular beam epitaxy and a systematic variation in the Gd and oxygen deposition rates, we have been able to observe sustained layer-by-layer epitaxial growth on yttria-stabilized cubic zirconia (001). The presence of Gd helps to stabilize the l

  23. R. S. Hundi, Sandip Pakvasa, Xerxes Tata

    We present a locally supersymmetric extension of the minimal supersymmetric Standard Model (MSSM) based on the gauge group $SU(3)_C\times SU(2)_L\times U(1)_Y\times U(1)^\prime$ where, except for the supersymmetry breaking scale which is fixed to be $\sim 10^{11}$ GeV, we require that all non-Standard-Model parameters allowed by the {\it local} spacetime and

  24. L. Isaev, G. Ortiz, J. Dukelsky

    We study the quantum phase diagram of the Heisenberg planar antiferromagnet with a subset of four-spin ring exchange interactions, using the recently proposed heirarchical mean-field approach. By identifying relevant degrees of freedom, we are able to use a single variational anzatz to map the entire phase diagram of the model and uncover the nature of its v

  25. Dmitry Malyshev, Ilias Cholis, Joseph Gelfand

    In this paper, we study the flux of electrons and positrons injected by pulsars and by annihilating or decaying dark matter in the context of recent ATIC, PAMELA, Fermi, and HESS data. We review the flux from a single pulsar and derive the flux from a distribution of pulsars. We point out that the particle acceleration in the pulsar magnetosphere is insuffic

  26. Justin Khoury, Mark Wyman

    We perform N-body simulations of theories with infinite-volume extra dimensions, such as the Dvali-Gabadadze-Porrati (DGP) model and its higher-dimensional generalizations, where 4D gravity is mediated by massive gravitons. The longitudinal mode of these gravitons mediates an extra scalar force, which we model as a density-dependent modification to the Poiss

  27. Muhammad Salman Asif, Justin Romberg

    The theory of compressive sensing (CS) suggests that under certain conditions, a sparse signal can be recovered from a small number of linear incoherent measurements. An effective class of reconstruction algorithms involve solving a convex optimization program that balances the L1 norm of the solution against a data fidelity term. Tremendous progress has bee

  28. Fabian Januszewski

    We give a construction of a wide class of modular symbols attached to reductive groups. As an application we construct a p-adic distribution interpolating the special values of the twisted Rankin-Selberg L-function attached to cuspidal automorphic representations of GL(n) and GL(n-1) over number fields. If the representations are ordinary at p, our distribut

  29. Julien Cassaigne, Francois Nicolas

    In 1938, Morse and Hedlund proved that the subword complexity function of an infinite word is either bounded or at least linearly growing. In 1982, Ehrenfeucht and Rozenberg proved that this gap property holds for the subword complexity function of any language. The aim of the present paper is to present a self-contained, compact proof of Ehrenfeucht and Roz

  30. Matthew P. Young

    We consider the family of Rankin-Selberg convolution L-functions of a fixed SL(3, Z) Maass form with the family of Hecke-Maass cusp forms on SL(2, Z). We estimate the second moment of this family of L-functions with a &#34;long&#34; integration in t-aspect. These L-functions are distinguished by their high degree (12) and large conductors (of size T^{12}).

  31. Bahram Mashhoon

    Electrodynamics of rotating systems is expected to exhibit novel nonlocal features that come about when acceleration-induced nonlocality is introduced into the special relativity theory in conformity with the Bohr-Rosenfeld principle. The implications of nonlocality for the amplitude and frequency of electromagnetic radiation received by uniformly rotating o

  32. Daniel Phillips, Andreas Albrecht

    The causal entropic principle aims to predict the unexpectedly small value of the cosmological constant Lambda using a weighting by entropy increase on causal diamonds. The original work assumed a purely isotropic and homogeneous cosmology. But even the level of inhomogeneity observed in our universe forces reconsideration of certain arguments about entropy

  33. Amos Yarom

    We compute fourth sound for superfluids dual to a charged scalar and a gauge field in an AdS_4 background. For holographic superfluids with condensates that have a large scaling dimension (greater than approximately two), we find that fourth sound approaches first sound at low temperatures. For condensates that a have a small scaling dimension it exhibits no

  34. Ashoke Sen

    Quantum entropy function is a proposal for computing the entropy associated with the horizon of a black hole in the extremal limit, and is related via AdS/CFT correspondence to the dimension of the Hilbert space in a dual quantum mechanics. We show that in N=4 supersymmetric string theories, quantum entropy function formalism naturally explains the origin of

  35. E. Wachowicz, T. Ossowski, A. Kiejna

    Structural, cohesive, and magnetic properties of two symmetric $\Sigma3(111)$ and $\Sigma5(210)$ tilt grain boundaries (GBs) in pure bcc Fe and in dilute FeCr alloys are studied from first principles. Different concentration and position of Cr solute atoms are considered. We found that Cr atoms placed in the GB interstice enhance the cohesion by 0.5-1.2 J/m$

  36. T. Fabčič, J. Main, G. Wunner

    In the preceding paper [T. Fabcic et al., preprint] &#34;restricted Gaussian wave packets&#34; were introduced for the regularized Coulomb problem in the four-dimensional Kustaanheimo-Stiefel coordinates, and their exact time propagation was derived analytically in a fictitious time variable. We now establish the Gaussian wave packet method for the hydrogen

  37. J. N. Esteves, M. Hirsch, W. Porod, J. C. Romao

    We reconsider the role that the possible detection of lepton flavour violating (LFV) decays of supersymmetric particles at the Large Hadron Collider (LHC) can play in helping reconstruct the underlying neutrino mass generation mechanism within the simplest high-scale minimal supergravity (mSUGRA) seesaw schemes. We study in detail the LFV scalar tau decays a

  38. Oliver DeWolfe, Christopher Rosen

    We probe the effectiveness and robustness of a simple gauge/gravity dual model of the QCD fireball that breaks conformal symmetry by constructing a family of similar geometries that solve the scalar/gravity equations of motion. This family has two parameters, one of which is associated to the temperature. We calculate two quantities, the speed of sound and t

  39. P. Neugebauer, M. Orlita, C. Faugeras, A. -L. Barra

    Fabrication of graphene structures has triggered vast research efforts focused on the properties of two-dimensional systems with massless Dirac fermions. Nevertheless, further progress in exploring this quantum electrodynamics system in solid-state laboratories seems to be limited by insufficient electronic quality of manmade structures and the crucial quest

  40. Cristiano De Michele

    Several physical systems in condensed matter have been modeled approximating their constituent particles as hard objects. The hard spheres model has been indeed one of the cornerstones of the computational and theoretical description in condensed matter. The next level of description is to consider particles as rigid objects of generic shape, which would enr

  41. Puri Arenas, Damiano Zanardini

    This volume contains the papers presented at WLPE 2008: the 18th Workshop on Logic-based Methods in Programming Environments held on 12th December, 2008 in Udine, Italy. It was held as a satellite workshop of ICLP 2008, the 24th International Conference on Logic Programming.

  42. Xuezhao Bao

    Here we propose that there is a lot of heat producing elements U and Th in the outer core of the Earth. The heat released from them may be the major energy source for driving the material movement within the interior of Earth, including plate motion. According to seismic tomography, the hottest area is the mantle under the central Pacific Ocean. Combined wit

  43. D. Kotschick

    We prove that any rational linear combination of Pontryagin numbers that is not a multiple of the signature is unbounded on connected closed oriented manifolds of nonnegative sectional curvature. Combining our result with Gromov&#39;s finiteness result for the signature yields a new characterization of the L-genus.

  44. Mark F. Flanagan, Enrico Paolini, Marco Chiani, Marc Fossorier

    In this paper, an expression for the asymptotic growth rate of the number of small linear-weight codewords of irregular doubly-generalized LDPC (D-GLDPC) codes is derived. The expression is compact and generalizes existing results for LDPC and generalized LDPC (GLDPC) codes. Ensembles with check or variable node minimum distance greater than 2 are shown to b

  45. D. Kotschick

    We prove that a rational linear combination of Chern numbers is an oriented diffeomorphism invariant of smooth complex projective varieties if and only if it is a linear combination of the Euler and Pontryagin numbers. In dimension at least three we prove that only multiples of the top Chern number, which is the Euler characteristic, are invariant under diff

  46. Heidi Forster, Markus Buttiker

    In linear transport, the fluctuation-dissipation theorem relates equilibrium current correlations to the linear conductance coefficient. Theory and experiment have shown that in small electrical conductors the non-linear I-V-characteristic of two-terminal conductor exhibits terms which are asymmetric in magnetic field and thus micro-reversibility is manifest

  47. O. A. Veliev

    In this paper, we investigate the three-dimensional Schrodinger operator with a periodic, relative to a lattice Ω of R3, potential q. A special class V of the periodic potentials is constructed, which is easily and constructively determined from the spectral invariants. First, we give an algorithm for the unique determination of the potential q in V of the t

  48. Katrin Tent, Martin Ziegler

    We introduce a new notion of computable function on $\R^N$ and prove some basic properties. We give two applications, first a short proof of Yoshinaga&#39;s theorem that periods are \el (they are actually low). We also show that the low complex numbers form a algebraically closed field closed under exponentiation and some other special functions.

  49. Juliana Kaizer Vizzotto, Andre Rauber Du Bois, Amr Sabry

    We express quantum computations (with measurements) using the arrow calculus extended with monadic constructions. This framework expresses quantum programming using well-understood and familiar classical patterns for programming in the presence of computational effects. In addition, the five laws of the arrow calculus provide a convenient framework for equat

  50. Erik Sjöqvist

    Everett&#39;s concept of relative state is used to introduce a geometric phase that depends nontrivially on entanglement in a pure quantum state. We show that this phase can be measured in multiparticle interferometry. A correlation-dependent generalization of the relative state geometric phase to mixed quantum states is outlined.

  51. J. P. Lansberg, T. N. Pham

    In the traditional non-relativistic bound state calculation, the two-photon decay amplitudes of the $P$-wave $χ_{c0,2}$ and $χ_{b0,2}$ states depend on the derivative of the wave function at the origin which can only be obtained from potential models. However by neglecting the relative quark momenta, the decay amplitude can be written as the matrix element o

  52. László Á. Gergely, Zoltán Keresztes, Marek Dwornik

    We derive the deflection angle of light rays passing near a black hole with mass m and tidal charge q, confined to a generalized Randall-Sundrum brane with codimension one. We employ the weak lensing approach, up to the second order in perturbation theory by two distinct methods. First we adopt a Lagrangian approach and derive the deflection angle from the a

  53. Vincent Mathieu

    We revisited a model for charmonium hybrid meson with a magnetic gluon [Yu. S. Kalashnikova and A. V. Nefediev, Phys. Rev. D {\bf 77}, 054025 (2008)] and improved the numerical calculations. These improvements support the hybrid meson interpretation of X(4260). Within the same model, we computed the hybrid meson mass with an electric gluon which is resolved

  54. Abdesslam Arhrib, Rachid Benbrik, Chuan-Hung Chen

    In this paper, the lepton flavor violating $τ\to \ell P(V)$ ($P,V= π^0, η, η^{\prime}, ρ^0, ω, ϕ$) and $τ\to 3\ell$ ($\ell = e, μ$) decays are studied in the framework of the type-III seesaw model, in which new triplet fermions with a zero hypercharge (Y=0) interact with ordinary lepton doublets via Yukawa couplings, and affect tree-level leptonic Z-boson co

  55. I. V. Strateva, S. Komossa

    We study the extended nuclear emission of the starburst galaxy NGC 1365. A weak obscured AGN and a strong starburst both contribute to the observed X-ray, optical, infrared, and radio emission in the inner 2kpc. The X-ray emission is spatially resolved, allowing comparison with multiwavelength data that highlights the structures dominating the nuclear region

  56. Jean-Luc Marichal

    We investigate the n-variable real functions G that are solutions of the Chisini functional equation F(x)=F(G(x),...,G(x)), where F is a given function of n real variables. We provide necessary and sufficient conditions on F for the existence and uniqueness of solutions. When F is nondecreasing in each variable, we show in a constructive way that if a soluti

  57. Adolfo Avella, Ferdinando Mancini, Satoru Odashima, Giovanni Scelza

    We analyze the two-orbital Hubbard model by means of the Composite Operator Method with the aim at studying the phenomenon of orbital selective Mott transition (OSMT). The model contains an interorbital interaction $U&#39;$, in addition to the usual intraorbital one $U$. As warming-up approximation, we use a basis of two operators only, the Hubbard operators

  58. Qing-Guo Huang

    The trispectrum is at least as important as the bispectrum and its size can be characterized by two parameters $τ_{NL}$ and $g_{NL}$. In this short paper, we focus on the Multi-brid inflation, in particular the two-brid inflation model in arXiv.0805.0974, and find that $τ_{NL}$ is always positive and roughly equals to $({6\over 5}f_{NL})^2$ for the low scale

  59. E. Armengau, M. Bauer, I. Bavykina, A. Benoit

    Workshop RPSCINT&#39;2008 was organized in Kyiv (Ukraine) on 9th and 10th September 2008. The idea was to bring together physicists, chemists, crystal scintillator experts and manufacturers to discuss the requirements of low-count rate experiments, in particular the required radiopurity and scintillation properties; selection and screening of input materials

  60. Sayan K. Chakrabarti, Pulak Ranjan Giri, Kumar S. Gupta

    We study the normal modes of a scalar field in the background of a warped AdS_3 black hole which arises in topologically massive gravity. We discuss the normal mode spectrum using the brick wall boundary condition. In addition, we investigate the possibility of a more general boundary condition for the scalar field.

  61. Christian Weedbrook, Daniel J. Alton, Thomas Symul, Ping Koy Lam

    We consider the distinguishability of Gaussian states from the view point of continuous-variable quantum cryptography using post-selection. Specifically, we use the probability of error to distinguish between two pure coherent (squeezed) states and two particular mixed symmetric coherent (squeezed) states where each mixed state is an incoherent mixture of tw

  62. Claus Gerhardt

    We prove the existence of a spectral resolution of the Wheeler-DeWitt equation when the matter field is provided by a massive Yang-Mills field. The resolution is achieved by first solving the free eigenvalue problem for the gravitational field and then the constrained eigenvalue problem for the Yang-Mills field. In the latter case the mass of the Yang-Mills

  63. Tom G. Mackay, Akhlesh Lakhtakia

    The planewave response of a linear passive material generally cannot be characterized by a single scalar refractive index, as directionality of energy flow and multiple wavevectors may need to be considered. This is especially significant for materials which support negative refraction, negative phase velocity, and counterposition. By means of a numerical ex

  64. Oleksiy Dovgoshey, Olli Martio

    We describe some Cartesian products of metric spaces and find conditions under which products of ultrametric spaces are ultrametric.

  65. H. Witala, R. Skibinski, J. Golak, W. Glockle

    We propose a novel approach to incorporate the proton-proton (pp) Coulomb force into the three-nucleon (3N) Faddeev calculations. The main new ingredient is a 3-dimensional screened pp Coulomb t-matrix obtained by a numerical solution of the 3-dimensional Lippmann-Schwinger (LS) equation. We demonstrate numerically and provide analytical insight that the ela

  66. William Nelson, Mairi Sakellariadou

    The possibility of having an inflationary epoch within a noncommutative geometry approach to unifying gravity and the standard model is demonstrated. This inflationary phase occurs without the need to introduce "ad hoc" additional fields or potentials, rather it is a consequence of a nonminimal coupling between the geometry and the Higgs field.

  67. Rene Lozi, Clarisse Fiol

    In this article, we study the behaviour of discrete one-dimensional dynamical systems associated to functions on finite sets. We formalise the global orbit pattern formed by all the periodic orbits (gop) as the ordered set of periods when the initial value thumbs the finite set in the increasing order. We are able to predict, using closed formulas, the numbe

  68. K. Iwasawa, D. B. Sanders, A. S. Evans, J. M. Mazzarella

    The Chandra component of the Great Observatories All-Sky LIRG Survey (GOALS) presently contains 44 luminous and ultraluminous infrared galaxies with log (Lir/Lsun) = 11.73-12.57. Omitting 15 obvious AGNs, the other galaxies are, on average, underluminous in the 2-10 keV band by 0.7 dex at a given far-infrared luminosity, compared to nearby star-forming galax

  69. N. Armesto

    I review the main predictions for the heavy-ion programme at the Large Hadron Collider (LHC) at CERN, as available in early April 2009. I begin by remembering the standard claims made in view of the experimental data measured at the Super Proton Synchrotron (SPS) at CERN and at the Relativistic Heavy Ion Collider (RHIC) at the BNL. These claims will be used

  70. Dieter Duyck, Joseph J. Boutros, Marc Moeneclaey

    We study Low-Density Parity-Check (LDPC) codes with iterative decoding on block-fading (BF) Relay Channels. We consider two users that employ coded cooperation, a variant of decode-and-forward with a smaller outage probability than the latter. An outage probability analysis for discrete constellations shows that full diversity can be achieved only when the c

  71. Céline Nadal, Satya N. Majumdar

    We study a system of $N$ non-intersecting $(1+1)$-dimensional fluctuating elastic interfaces (`vicious bridges&#39;) at thermal equilibrium, each subject to periodic boundary condition in the longitudinal direction and in presence of a substrate that induces an external confining potential for each interface. We show that, for a large system and with an appr

  72. Xian Gao

    We investigate the effects of the presence of relic classical superhorizon inhomogeneities during inflation. This superhorizon inhomogeneity appears as a gradient locally and picks out a preferred direction. Quantum fluctuations on this slightly inhomogeneous background are generally statistical anisotropic. We find a quadrupole modification to the ordinary

  73. Benjamin Graham, Geoffrey Grimmett

    A sharp-threshold theorem is proved for box-crossing probabilities on the square lattice. The models in question are the random-cluster model near the self-dual point $p_{\mathrm {sd}}(q)=\sqrt{q}/(1+\sqrt{q})$, the Ising model with external field, and the colored random-cluster model. The principal technique is an extension of the influence theorem for mono

  74. A. Bhattacharyay

    In a one dimensional superconductor where current driven phase transitions occur between superconducting and normal phases, both the phases coexist in a metastable regime over a wide range of current near the critical current $j_c$. A lot of spatio-temporal localized forms of the the competing phases have been identified in this so called resistive regime. I

  75. Michele Burrello, Haitan Xu, Giuseppe Mussardo, Xin Wan

    We study an efficient algorithm to hash any single qubit gate (or unitary matrix) into a braid of Fibonacci anyons represented by a product of icosahedral group elements. By representing the group elements by braid segments of different lengths, we introduce a series of pseudo-groups. Joining these braid segments in a renormalization group fashion, we obtain

  76. Bergfinnur Durhuus, Victor Gayral

    We investigate scattering properties of a Moyal deformed version of the nonlinear Schrödinger equation in an even number of space dimensions. With rather weak conditions on the degree of nonlinearity, the Cauchy problem for general initial data has a unique globally defined solution, and also has soliton solutions if the interaction potential is suitably cho

  77. Fan Ding, Hansjörg Geiges

    As shown by H. Gluck in 1962, the diffeotopy group of S^1 \times S^2 is isomorphic to Z_2 + Z_2 + Z_2. Here an alternative proof of this result is given, relying on contact topology. We then discuss two applications to contact topology: (i) it is shown that the fundamental group of the space of contact structures on S^1 \times S^2, based at the standard tigh

  78. Amjad Ashoorioon, Hassan Firouzjahi, M. M. Sheikh-Jabbari

    We propose an inflationary scenario, M-flation, in which inflation is driven by three $N\times N$ hermitian matrices $Φ_i, i=1,2,3$. The inflation potential of our model, which is strongly motivated from string theory, is constructed from $Φ_{i}$ and their commutators. We show that one can consistently restrict the classical dynamics to a sector in which the

  79. Bimalendu Deb, Jisha Hazra

    We show that it is possible to change not only s-wave but also higher partial wave atom-atom interactions in cold collision in the presence of relatively intense laser fields tuned near a photoassociative transition.

  80. Neri Merhav

    We provide a simple physical interpretation, in the context of the second law of thermodynamics, to the information inequality (a.k.a. the Gibbs&#39; inequality, which is also equivalent to the log-sum inequality), asserting that the relative entropy between two probability distributions cannot be negative. Since this inequality stands at the basis of the da

  81. Shuhei Nakakura, Yuki Nagai, Daijiro Yoshioka

    Graphene exhibits zero-gap massless-Dirac fermion and zero density of states at E = 0. These particles form localized states called edge states on finite width strip with zigzag edges at E = 0. Naively thinking, one may expect that current is also concentrated at the edge, but Zarbo and Nikolic numerically obtained a result that the current density shows max

  82. Denis J. Evans, Debra J. Searles, Stephen R. Williams

    Using the Dissipation Theorem and a corollary of the Fluctuation Theorem, namely the Second Law Inequality, we give a first-principles derivation of Boltzmann&#39;s postulate of equal a priori probability in phase space for the microcanonical ensemble. We show that if the initial distribution differs from the uniform distribution over the energy hypersurface

  83. Hsin-Hua Lai, Olexei I. Motrunich

    We study effects of nonmagnetic impurities in a Spin Bose-Metal (SBM) phase discovered in a two-leg triangular strip spin-1/2 model with ring exchanges (D. N. Shenget al, arXiv:0902.4210). This phase is a quasi-1D descendant of a 2D spin liquid with spinon Fermi sea, and the present study aims at interpolating between the 1D and 2D cases. Different types of

  84. Arno van den Essen, Roel Willems, Wenhua Zhao

    In this paper we prove four cases of the vanishing conjecture of differential operators with constant coefficients and also a conjecture on the Laurent polynomials with no holomorphic parts, which were proposed in [Zh3] by the third named author. We also give two examples to show that the generalizations of both the vanishing conjecture and the Duistermaat-v

  85. Xiao-Hai Liu, Yuan-Jiang Zhang, Qiang Zhao

    In the $J/ψ$ radiative decay channels $J/ψ\to γV\bar{V}$, the result of partial wave analysis indicates that the $V\bar{V}$ systems are predominately pseudoscalar component, and most of these channels have relatively large branching ratios at an order of $10^{-3}$. Meanwhile, vector mesons, such as $ρ$, $ω$ and $K^*$, have strong couplings with nucleons and/

  86. Pierre Berger

    For every $C^2$-small function $B$, we prove that the map $(x,y)\mapsto (x^2+a,0)+B(x,y,a)$ leaves invariant a physical, SRB probability measure, for a set of parameters $a$ of positive Lebesgue measure. When the perturbation $B$ is zero, this is the Jakobson Theorem; when the perturbation is a small constant times $(0,x)$, this is the celebrated Benedicks-C

  87. Viqar Husain, Daniel R. Terno

    The gravity-scalar field system in spherical symmetry provides a natural setting for exploring gravitational collapse and its aftermath in quantum gravity. In a canonical approach, we give constructions of the Hamiltonian operator, and of semiclassical states peaked on constraint free data. Such states provide explicit examples of physical states. We also sh

  88. Yves Felix, Gregory Lupton, Samuel B. Smith

    Let Aut(p) denote the topological monoid of self-fibre-homotopy equivalences of a fibration p:E\to B. We make a general study of this monoid, especially in rational homotopy theory. When E and B are simply connected CW complexes with E finite, we identify the rational Samelson Lie algebra of the identity component of Aut(p) as the homology of a certain DG Li

  89. Evgeny Epelbaum, Hermann Krebs, Dean Lee, Ulf-G. Meißner

    We consider low-energy nucleons at next-to-next-to-leading order in lattice chiral effective field theory. Three-body interactions first appear at this order, and we discuss several methods for determining three-body interaction coefficients on the lattice. We compute the energy of the triton and low-energy neutron-deuteron scattering phase shifts in the spi

  90. Ali Nassimi, Raymond Kapral

    The calculation of quantum canonical time correlation functions is considered in this paper. Transport properties, such as diffusion and reaction rate coefficients, can be determined from time integrals of these correlation functions. Approximate, quantum-classical expressions for correlation functions, which are amenable to simulation, are derived. These ex

  91. Pouyan Ghaemi, Shinsei Ryu, Dung-Hai Lee

    We argue that by inducing superconductivity in graphene via the proximity effect, it is possible to observes the &#34;quantum valley Hall effect&#34;. In the presence of magnetic field, supercurrent causes &#34;valley pseudospin&#34; to accumulate at the edges of the superconducting strip. This, and the structure of the superconducting vortex core, provide p

  92. Sundar Srinivasan, Margaret Meixner, Claus Leitherer, Uma Vijh

    We present empirical relations describing excess emission from evolved stars in the Large Magellanic Cloud (LMC) using data from the SAGE (Surveying the Agents of a Galaxy&#39;s Evolution) survey which includes the IRAC 3.6, 4.5, 5.8 and 8.0 μm and MIPS 24, 70 and 160 μm bands. We combine the SAGE data with the Two Micron All Sky Survey (2MASS; J, H and Ks)

  93. K. Beloy, V. A. Dzuba, A. Derevianko

    We carry out relativistic many-body calculations of the Stark-induced absorption coefficient on the 254-nm $6s6p ^3P_1 (F=1/2) - 6s^2 ^1S_0$ line of $^{199}$Hg atom, the effect considered before by Lamoreaux and Fortson using a simple central field estimate [Phys. Rev. A {\bf 46}, 7053 (1992)]. The Stark-induced admixing of states of opposite parity opens ad

  94. Zhe Chen

    The Sudoku puzzle has achieved worldwide popularity recently, and attracted great attention of the computational intelligence community. Sudoku is always considered as Satisfiability Problem or Constraint Satisfaction Problem. In this paper, we propose to focus on the essential graph structure underlying the Sudoku puzzle. First, we formalize Sudoku as a gra

  95. B. T. Draine

    The wavelength dependences of interstellar extinction and polarization, supplemented by observed elemental abundances and the spectrum of infrared emission from dust heated by starlight, strongly constrain dust models. One dust model that appears to be consistent with observations is presented. To reproduce the observed extinction, the model consumes the bul

  96. Lauren A. Britton, Wilma K. Olson, Irwin Tobias

    Because of the double-helical structure of DNA, in which two strands of complementary nucleotides intertwine around each other, a covalently closed DNA molecule with no interruptions in either strand can be viewed as two interlocked single-stranded rings. Two closed space curves have long been known by mathematicians to exhibit a property called the linking

  97. J. Glosik, R. Plasil, I. Korolov, T. Kotrik

    We study binary and the recently discovered process of ternary He-assisted recombination of H3+ ions with electrons in a low temperature afterglow plasma. The experiments are carried out over a broad range of pressures and temperatures of an afterglow plasma in a helium buffer gas. Binary and He-assisted ternary recombination are observed and the correspondi

  98. Seungoh Ryu

    We consider aspects of the population dynamics, inside a bound domain, of diffusing agents carrying an attribute which is stochastically destroyed upon contact with the boundary. The normal mode analysis of the relevant Helmholtz equation under the partially absorbing, but uniform, boundary condition provides a starting framework in understanding detailed ev

  99. Seungoh Ryu, David Linton Johnson

    We consider the Helmholtz problem in the context of the evolution of uniform initial distribution of a physical attribute in general porous media subject to a partially absorbing boundary condition. Its spectral property as a reflection of the boundary geometry has been widely exploited, such as in biological and geophysical applications. We consider the sit

  100. D. J. Scheeres, T. S. Statler, K. T. Alfriend, P. Armitage

    Given the impressive investment by the nation in observational Astronomy and Astrophysics facilities coming on line now and in the near future, we advocate for an increased investment in applied and fundamental research on Astrophysical and Celestial Dynamics (ACD). Specifically we call for a) continued and expanded support for applied research in ACD, b) cr