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December 2007 arXiv papers — page 21

Showing 2,0012,100 of 4,627 papers

  1. Ali Naji, Alex J. Levine, Philip A. Pincus

    Recent experiments by Y. Gambin et al. [PNAS 103, 2098 (2006)] have called into question the applicability of the Saffman-Delbruck diffusivity for proteins embedded in the lipid bilayers. We present a simple argument to account for this observation that should be generically valid for a large class of transmembrane and membrane bound proteins. Whenever the p

  2. L. Sunil Chandran, Anita Das, Chintan Shah

    A $k$-dimensional box is the cartesian product $R_1 \times R_2 \times ... \times R_k$ where each $R_i$ is a closed interval on the real line. The {\it boxicity} of a graph $G$, denoted as $box(G)$, is the minimum integer $k$ such that $G$ is the intersection graph of a collection of $k$-dimensional boxes. A unit cube in $k$-dimensional space or a $k$-cube is

  3. Bence Toth, Enrico Scalas

    We present results on simulations of a stock market with heterogeneous, cumulative information setup. We find a non-monotonic behaviour of traders' returns as a function of their information level. Particularly, the average informed agents underperform random traders; only the most informed agents are able to beat the market. We also study the effect of

  4. Noureddine Chair

    We show explicitly that the sum over punctures for the three times derivative for the Penner free energy $F_{0}^{3}$, given by D.A. Johnston, Phys.Rev.D 51 (1995) is not correct. As a consequence, Eq.(21), the differentiated version for the renormalization group (RG) equation, is wrong. Also, his conclusion that the differentiated version of the (RG) equatio

  5. R. Lopez-Ruiz, J. Gonzalez-Estevez, M. G. Cosenza, J. R. Sanchez

    In this work, an ensemble of economic interacting agents is considered. The agents are arranged in a linear array where only local couplings are allowed. The deterministic dynamics of each agent is given by a map. This map is expressed by two factors. The first one is a linear term that models the expansion of the agent's economy and that is controlled b

  6. Chen Jacoby, Shmuel Nussinov

    We discuss the relic abundance of massive long lived colored particles with mass of the order of 1 TeV. We first examine the case where the massive colored particles have the standard color only. Next we consider the "Quirk Model" suggested by M. Luty, in which the colored particles transform under an additional non-abelian gauge group with a scale m

  7. Ali Naji, Frank L. H. Brown

    We present a position Langevin equation for overdamped particle motion on rough two-dimensional surfaces. A Brownian Dynamics algorithm is suggested to evolve this equation numerically, allowing for the prediction of effective (projected) diffusion coefficients over corrugated surfaces. In the case of static surface roughness, we find that a simple area-scal

  8. P. Balister, S. Gerke, G. Gutin

    A non-empty set $X$ of vertices of an acyclic digraph is called connected if the underlying undirected graph induced by $X$ is connected and it is called convex if no two vertices of $X$ are connected by a directed path in which some vertices are not in $X$. The set of convex sets (connected convex sets) of an acyclic digraph $D$ is denoted by $\sco(D)$ ($\s

  9. V. V. Mochalov, S. B. Nurushev, A. N. Vasiliev, N. A. Bazhanov

    Single-spin asymmetries $A_N$ in reactions p+p(pol)->π^0 + X and π^-+p(pol)->π^0 + X at 50 and 40 GeV/c respectively behave in drastically different ways in function of transverse momentum in the central region. At the same time $A_N$ in the polarized proton fragmentation region of these reactions are practically coinciding. Our new data on the analyzing pow

  10. Francis Comets, Francois Delarue, René Schott

    We provide a large deviations analysis of deadlock phenomena occurring in distributed systems sharing common resources. In our model transition probabilities of resource allocation and deallocation are time and space dependent. The process is driven by an ergodic Markov chain and is reflected on the boundary of the d-dimensional cube. In the large resource l

  11. Utpal Sarkar

    In this review we discuss how the models of neutrino masses can accommodate solutions to the problem of matter-antimatter asymmetry in the universe, dark energy or cosmological constant problem and dark matter candidates. The matter-antimatter asymmetry is explained by leptogenesis, originating from the lepton number violation associated with the neutrino ma

  12. Ivan L. Garanovich, Andrey A. Sukhorukov, Yuri S. Kivshar

    We predict that interfaces of modulated photonic lattices can support a novel type of generic surface states. Such linear surface states appear in truncated but otherwise perfect (defect-free) lattices as a direct consequence of the periodic modulation of the lattice potential, without any embedded or nonlinearity-induced defects. This is in a sharp contrast

  13. A. A. Grib, Yu. V. Pavlov

    The hypothesis that dark matter consists of superheavy particles with the mass close to the Grand Unification scale is investigated. These particles were created from vacuum by the gravitation of the expanding Universe and their decay led to the observable baryon charge. Some part of these particles with the lifetime larger than the time of breaking of the G

  14. G. Eichmann, A. Krassnigg, M. Schwinzerl, R. Alkofer

    Established results for the quark propagator in Landau gauge QCD, together with a detailed comparison to lattice data, are used to formulate a Poincare covariant Faddeev approach to the nucleon. The resultant three-quark amplitudes describe the quark core of the nucleon. The nucleon's mass and its electromagnetic form factors are calculated as functions of t

  15. Erika Andersson, Daniel K. L. Oi

    Generalized quantum measurements (POVMs or POMs) are important for optimally extracting information for quantum communication and computation. The standard realization via the Neumark extension requires extensive resources in the form of operations in an extended Hilbert space. For an arbitrary measurement, we show how to construct a binary search tree with

  16. Amir Levinson, Omer Bromberg

    We consider some implications of the rapid X-ray and TeV variability observed in M87 and the TeV blazars. We outline a model for jet focusing and demonstrate that modest radiative cooling can lead to recollimation of a relativistic jet in a nozzle having a very small cross-sectional radius. Such a configuration can produce rapid variability at large distance

  17. D. Orozco Suarez, L. R. Bellot Rubio, J. C. del Toro Iniesta, S. Tsuneta

    We describe a new form of small-scale magnetic flux emergence in the quiet Sun. This process seems to take vertical magnetic fields from the solar interior to the photosphere, where they appear above granular convection cells. High-cadence time series of spectropolarimetric measurements obtained by Hinode in a quiet region near disk center are analyzed. We e

  18. M. Baldo, C. Maieron

    Neutron matter at low density is studied within the hole-line expansion. Calculations are performed in the range of Fermi momentum $k_F$ between 0.4 and 0.8 fm$^{-1}$. It is found that the Equation of State is determined by the $^1S_0$ channel only, the three-body forces contribution is quite small, the effect of the single particle potential is negligible a

  19. P. Balister, S. Gerke, G. Gutin, A. Johnstone

    A set $X$ of vertices of an acyclic digraph $D$ is convex if $X\neq \emptyset$ and there is no directed path between vertices of $X$ which contains a vertex not in $X$. A set $X$ is connected if $X\neq \emptyset$ and the underlying undirected graph of the subgraph of $D$ induced by $X$ is connected. Connected convex sets and convex sets of acyclic digraphs a

  20. Martin Kiemes, Heinz Horner

    We study the dynamical low temperature behaviour of the Ising spin glass on the Bethe lattice. Starting from Glauber dynamics we propose a cavity like Ansatz that allows for the treatment of the slow (low temperature) part of dynamics. Assuming a continuous phase transitions and ultrametricity with respect to long time scales we approach the problem perturba

  21. Rima Izem, J. S. Marron

    A set of curves or images of similar shape is an increasingly common functional data set collected in the sciences. Principal Component Analysis (PCA) is the most widely used technique to decompose variation in functional data. However, the linear modes of variation found by PCA are not always interpretable by the experimenters. In addition, the modes of var

  22. Gracjan Maciejewski

    In this paper research projects based on the wide-field CCD photometry performed in Piwnice Observatory are discussed. The used telescopes, as well as dedicated software pipeline for data reduction are presented. The prospects for collaboration between Polish and Bulgarian institutes in the field of wide-field photometry are also discussed.

  23. P. Spathis, H. Aubin, A. Pourret, K. Behnia

    We present a study of the Nernst effect in amorphous 2D superconductor InO$_x$, whose low carrier density implies low phase rigidity and strong superconducting phase fluctuations. Instead of presenting the abrupt jump expected at a BCS transition, the Nernst signal evolves continuously through the superconducting transition as previously observed in underdop

  24. A. Pȩkalski, J. Szwabiński, I. Bena, M. Droz

    We investigate in detail the model of a trophic web proposed by Amaral and Meyer [Phys. Rev. Lett. 82, 652 (1999)]. We focused on small-size systems that are relevant for real biological food webs and for which the fluctuations are playing an important role. We show, using Monte Carlo simulations, that such webs can be non-viable, leading to extinction of al

  25. Hai-Chuan Guo, Ren-Xin Xu, Cheng-Min Zhang

    We study the layer of electrons on bare strange star surfaces, taking the Dirac exchange-energy into account. Because electrons are fermions, the electron wave function must be of exchange-antisymmetry. The Dirac exchange-energy originates, consequently, from the exchange-antisymmetry of electron wave functions. This consideration may result in changing the

  26. P. Kleinert, V. V. Bryksin

    A spin-rotation symmetry in spin-orbit coupled two-dimensional electron systems gives rise to a long-lived spin excitation that is robust against short-range impurity scattering. The influence of a constant in-plane electric field on this persistent spin helix is studied. To probe the field-induced eigen-modes of the spin-charge coupled system, a surface aco

  27. Francesco Brenti, Volkmar Welker

    Let $(a_n)_{n \geq 0}$ be a sequence of complex numbers such that its generating series satisfies $\sum_{n \geq 0} a_nt^n = \frac{h(t)}{(1-t)^d}$ for some polynomial $h(t)$. For any $r \geq 1$ we study the transformation of the coefficient series of $h(t)$ to that of $h^{< r >}(t)$ where $\sum_{n \geq 0} a_{nr} t^n = \frac{h^{< r >}(t)}{(1-t)^d}$. We give a

  28. Rawan Ghnemat, Saleh Oqeili, Cyrille Bertelle, Gérard Henry Edmond Duchamp

    In this chapter, we deal with some specific domains of applications to game theory. This is one of the major class of models in the new approaches of modelling in the economic domain. For that, we use genetic automata which allow to build adaptive strategies for the players. We explain how the automata-based formalism proposed - matrix representation of auto

  29. Pierrick Tranouez, Cyrille Bertelle, Damien Olivier

    We describe here our perception of complex systems, of how we feel the different layers of description are important part of a correct complex system simulation. We describe a rough models categorization between rules based and law based, of how these categories handled the levels of descriptions or scales. We then describe our fluid flow simulation, which c

  30. Stephane Roux, François Hild, Philippe Viot, Dominique Bernard

    A new methodology is proposed to estimate 3D displacement fields from pairs of images obtained from X-Ray Computed Micro Tomography (XCMT). Contrary to local approaches, a global approach is followed herein that evaluates {\em continuous} displacement fields. Although any displacement basis could be considered, the procedure is specialized to finite element

  31. Yeow Meng Chee, Charles J. Colbourn, Alan C. H. Ling

    Off-chip buses account for a significant portion of the total system power consumed in embedded systems. Bus encoding schemes have been proposed to minimize power dissipation, but none has been demonstrated to be optimal with respect to any measure. In this paper, we give the first provably optimal and explicit (polynomial-time constructible) families of mem

  32. Chih Hao Hsia, Jin Zeng Li, Wing-Huen Ip

    Here we present initial results of our search for extensive halos around the planetary nebulae (PNe) in our Galaxy based on imaging data from the Southern H-Alpha Sky Survey Atlas (SHASSA). A threshold surface brightness in H$α$ emission was used to help identify the spatially extended features of the PNe. We investigated a sample that included 10 PNe, the l

  33. Taku J Sato, Shiro Kashimoto, Chihiro Masuda, Takahiro Onimaru

    Spin correlations and fluctuations in the 3d-transition-metal-based icosahedral quasicrystal Zn-Fe-Sc have been investigated by neutron scattering using polycrystalline samples. Magnetic diffuse scattering has been observed in the elastic experiment at low temperatures, indicating development of static short-range-spin correlations. In addition, the inelasti

  34. Thomas A. Gardiner, James M. Stone

    We present a single step, second-order accurate Godunov scheme for ideal MHD which is an extension of the method described by Gardiner & Stone (2005) to three dimensions. This algorithm combines the corner transport upwind (CTU) method of Colella for multidimensional integration, and the constrained transport (CT) algorithm for preserving the divergence-free

  35. Baruch Feldman, Rui Deng, Scott T. Dunham

    We extend quantum models of nanowire surface scattering to incorporate bulk resistivity and extract an expression for the increased resistivity due to surface roughness. To learn how to improve conductivity, we calculate conductivity degradation from individual wavelengths of surface roughness, and show how these can be convolved to give resistivity for arbi

  36. Angel P. Popov, Todor D. Todorov

    We derive explicit formulas for calculating $e^A$, $\cosh{A}$, $\sinh{A}, \cos{A}$ and $\sin{A}$ for a given $2\times2$ matrix $A$. We also derive explicit formulas for $e^A$ for a given $3\times3$ matrix $A$. These formulas are expressed exclusively in terms of the characteristic roots of $A$ and involve neither the eigenvectors of $A$, nor the transition m

  37. Nestor Zorzano, Daniel Merino, J. L. J. Laredo, J. P. Sevilla

    This paper introduces a procedure based on genetic programming to evolve XSLT programs (usually called stylesheets or logicsheets). XSLT is a general purpose, document-oriented functional language, generally used to transform XML documents (or, in general, solve any problem that can be coded as an XML document). The proposed solution uses a tree representati

  38. M. K. Suleymanov, E. U. Khan, A Kravchakova, Mahnaz Q. Haseeb

    The centrality experiments indicate regime change and saturation in the behavior of some characteristics of the secondary particles emitted in hadron-nuclear and nuclear-nuclear interactions at high energies. The phenomenon has a critical character. The simple models do not explain the effect. We suppose that the responsible mechanism to explain the phenomen

  39. S. I. Ipatov

    Fractions of asteroidal particles, particles originating beyond Jupiter&#39;s orbit (including trans-Neptunian particles), and cometary particles originating inside Jupiter&#39;s orbit among zodiacal dust are estimated to be about 1/3 each, with a possible deviation from 1/3 up to 0.1-0.2. These estimates were based on the comparison of our models of the zod

  40. Yuan Li, Aigen Li, Daming Wei

    The dust extinction of gamma-ray bursts (GRBs) host galaxies, containing important clues to the nature of GRB progenitors and crucial for dereddening, is still poorly known. Here we propose a straightforward method to determine the extinction of GRB host galaxies by comparing the observed optical spectra to the intrinsic ones extrapolated from the X-ray spec

  41. E. T. Tomboulis

    In a recent note (arXiv:0711.4930[hep-th]) Ito and Seiler claim that there is a &#39;missing link&#39; in the derivation in arXiv:0707.2179[hep-th] by the present author; namely, that no proof of a certain inequality used there is given at weak coupling. Here it is pointed out that in fact no such missing link is present. The argument in 0707.2179 is, among

  42. Yeow Meng Chee

    We construct a record-breaking binary code of length 17, minimal distance 6, constant weight 6, and containing 113 codewords.

  43. Yeow Meng Chee, Alan C. H. Ling

    The problem of determining extremal hypergraphs containing at most r isomorphic copies of some element of a given hypergraph family was first studied by Boros et al. in 2001. There are not many hypergraph families for which exact results are known concerning the size of the corresponding extremal hypergraphs, except for those equivalent to the classical Tura

  44. David G. Barnes, Grenville Armitage

    The forthcoming generation of radiotelescopes pose new and substantial challenges in terms of system monitoring. Information regarding environmental conditions, signal connectivity and level, processor utilisation, memory use, network traffic and even power consumption needs to be collected, displayed in realtime, and preserved in a permanent database. In th

  45. Ryu Sasaki

    Exact solvability of two typical examples of the discrete quantum mechanics, i.e. the dynamics of the Meixner-Pollaczek and the continuous Hahn polynomials with full parameters, is newly demonstrated both at the Schroedinger and Heisenberg picture levels. A new quasi exactly solvable difference equation is constructed by crossing these two dynamics, that is,

  46. Alexei Bazavov, Bernd A. Berg

    Deconfined regions created in heavy ion collisions are bordered by the confined phase. We discuss boundary conditions (BCs) to model a cold exterior. Monte Carlo simulations of pure SU(3) lattice gauge theory with thus inspired BCs show scaling. Corrections to usual results survive in the finite volume continuum limit and we estimate them in a range from L=5

  47. Wei Chao, Shu Luo, Zhi-zhong Xing, Shun Zhou

    A natural extension of the standard model to accommodate massive neutrinos is to introduce one Higgs triplet and three right-handed Majorana neutrinos, leading to a 6 \times6 neutrino mass matrix. We show that three light Majorana neutrinos (i.e., the mass eigenstates of ν_e, ν_μand ν_τ) are exactly massless, if and only if M_L = M_D M^{-1}_R M^T_D exactly h

  48. Zhi-zhong Xing, He Zhang, Shun Zhou

    Assuming the Majorana nature of massive neutrinos, we generalize the Friedberg-Lee neutrino mass model to include CP violation in the neutrino mass matrix M_ν. The most general case with all the free parameters of M_νbeing complex is discussed. We show that a favorable neutrino mixing pattern (with θ_12 \approx 35.3^\circ, θ_23=45^\circ, θ_13 \neq 0^\circ an

  49. Shu Luo, Zhi-zhong Xing

    Current experimental data allow the zero value for one neutrino mass, either m_1 =0 or m_3 =0. This observation implies that a realistic neutrino mass texture can be established by starting from the limit (a) m_1 = m_2 =0 and m_3 \neq 0 or (b) m_1 = m_2 \neq 0 and m_3 =0. In both cases, we may introduce a particular perturbation which ensures the resultant n

  50. Zhi-zhong Xing, Shun Zhou

    In this talk, we first give a brief review of the so-called minimal seesaw models and then concentrate on the minimal type-I seesaw model with two almost degenerate right-handed Majorana neutrinos of ${\cal O}(1 {\rm TeV})$. A specific texture of the neutrino Yukawa coupling matrix is proposed to achieve the nearly tri-bimaximal neutrino mixing pattern. This

  51. Maximilian Schlosshauer, Andrew P. Hines, Gerard J. Milburn

    We derive and analyze the Born-Markov master equation for a quantum harmonic oscillator interacting with a bath of independent two-level systems. This hitherto virtually unexplored model plays a fundamental role as one of the four &#34;canonical&#34; system-environment models for decoherence and dissipation. To investigate the influence of further couplings

  52. Grenville J. Croll

    The author proposes, a priori, a simple set of principles that can be developed into a range of algorithms by which means the Torah might be decoded. It is assumed that the Torah is some form of transposition cipher with the unusual property that the plain text of the Torah may also be the cipher text of one or more other documents written in Biblical Hebrew

  53. Y. Kasahara, T. Iwasawa, Y. Shimizu, H. Shishido

    Quasi-two dimensional CeIrIn5 contains two distinct domes with different heavy fermion superconducting states in its phase diagram. Here we pinned down the superconducting gap structure of CeIrIn5 in the second dome, located away from the antiferromagnetic quantum critical point, by the thermal transport measurements in magnetic fields rotated relative to th

  54. Todor D. Todorov, Hans Vernaeve

    We construct an algebra of generalized functions endowed with a canonical embedding of the space of Schwartz distributions. We offer a solution to the problem of multiplication of Schwartz distributions similar to but different from Colombeau&#39;s solution. We show that the set of scalars of our algebra is an algebraically closed field unlike its counterpar

  55. Lev Birbrair, Alexandre Fernandes

    We compute Hoelder Complexes,i.e. the complete bi-Lipschitz invariants, for germs of real weighed homogeneous algebraic or semialgebraic surfaces.

  56. Chia-Lung Wu, Po-Ning Chen, Yunghsiang S. Han, Ming-Hsin Kuo

    The code that combines channel estimation and error protection has received general attention recently, and has been considered a promising methodology to compensate multi-path fading effect. It has been shown by simulations that such code design can considerably improve the system performance over the conventional design with separate channel estimation and

  57. I. I. Balega, Yu. Yu. Balega, A. F. Maksimov, E. V. Malogolovets

    The results of speckle interferometric observations of 104 binary and 6 triple stars performed at the BTA 6 m telescope in 2004 October are presented. Nearby low-mass stars are mostly observed for the program, among which 59 there are new binaries recently discovered by the Hipparcos astrometric satellite. Concurrently with the diffraction-limited position m

  58. Rafael R. Kamalian, Petros A. Petrosyan

    The lower bound W(K_{2n})>=3n-2 is proved for the greatest possible number of colors in an interval edge coloring of the complete graph K_{2n}.

  59. C. Beck, W. Schmidt, R. Rezaei, W. Rammacher

    We analyze a 1-hour time series of Ca II H intensity spectra and polarimetric spectra around 630 nm to derive the signature of the chromospheric heating and to investigate its relation to magnetic fields. We derived several characteristic quantities of Ca II H to define the chromospheric atmosphere properties. We study the power of the Fourier transform at d

  60. Simon Catterall

    We show how to derive the supersymmetric orbifold lattices of Cohen et al. \cite{Cohen:2003xe,Cohen:2003qw} and Kaplan et al. \cite{Kaplan:2005ta} by direct discretization of an appropriate twisted supersymmetric Yang-Mills theory. We examine in detail the four supercharge two dimensional theory and the theory with sixteen supercharges in four dimensions. Th

  61. John W. Barrett, Xiaobing Feng, Andreas Prohl

    Motivated by emerging applications from imaging processing, the heat flow of a generalized $p$-harmonic map into spheres is studied for the whole spectrum, $1\leq p<\infty$, in a unified framework. The existence of global weak solutions is established for the flow using the energy method together with a regularization and a penalization technique. In particu

  62. Wouter Bos, Jean-Pierre Bertoglio

    A new single-time two-point closure is proposed, in which the equation for the two-point correlation between the displacement of a fluid particle and the velocity allows one to estimate a Lagrangian timescale. This timescale is used to specify the nonlinear damping of triple correlations in the closure. A closed set of equations is obtained without ad hoc co

  63. Toshizumi Fukui, Krzysztof Kurdyka, Laurentiu Paunescu

    We give several versions of local and global inverse mapping theorem for tame non necessarily smooth, mappings. Here tame mapping means a mapping which is subanalytic or, more generally, definable in some o-minimal structure. Our sufficient conditions are formulated in terms of various properties (convexity, positivity of some principal minors, contractiblit

  64. Kaustubh Agashe, Adam Falkowski, Ian Low, Geraldine Servant

    We construct models with a Kaluza-Klein (KK) parity in a five- dimensional warped geometry, in an attempt to address the little hierarchy problem present in setups with bulk Standard Model fields. The lightest KK particle (LKP) is stable and can play the role of dark matter. We consider the possibilities of gluing two identical slices of 5D AdS in either the

  65. Lawrence J. Hall, Yasunori Nomura

    In any theory it is unnatural if the observed parameters lie very close to special values that determine the existence of complex structures necessary for observers. A naturalness probability, P, is introduced to numerically evaluate the unnaturalness. If P is small in all known theories, there is an observer naturalness problem. In addition to the well-know

  66. Troels Haugboelle, Jesper Sommer-Larsen, Kristian Pedersen

    The Sunyaev-Zeldovich (SZ) effect gives a measure of the thermal energy and electron pressure in groups and clusters of galaxies. In the near future SZ surveys will map hundreds of systems, shedding light on the pressure distribution in the systems. The thermal energy is related to the total mass of a system of galaxies, but it is only a projection that is o

  67. Pietro A. Grassi, Matteo Marescotti

    We address the basic problem of constructing the Thom class for a supermanifold. Given a cohomological class of a supermanifold and the restriction of the supermanifold to its bosonic submanifold, the Thom class gives a prescription to define the integral over the bosonic submanifold in terms of the integral over the entire supermanifold. In addition, we pro

  68. Benjamin T. Graham

    We study the zero-range process on the complete graph. It is a Markov chain model for a microcanonical ensemble. We prove that the process converges to a fluid limit. The fluid limit rapidly relaxes to the appropriate Gibbs distribution.

  69. Abhijit Champanerkar, Ilya Kofman

    Quasi-alternating links are homologically thin for both Khovanov homology and knot Floer homology. We show that every quasi-alternating link gives rise to an infinite family of quasi-alternating links obtained by replacing a crossing with an alternating rational tangle. Consequently, we show that many pretzel links are quasi-alternating, and we determine the

  70. Ishwaree P. Neupane, Christoph Scherer

    In the first part of this paper, we outline the construction of an inflationary cosmology in the framework where inflation is described by a universally evolving scalar field, with the Lagrangian ${\cal L}_\phi=-{1/2}(\partial\phi)^2 -V(\phi)$. By considering a generic situation that inflaton attains a nearly constant velocity, during inflation, $m_P^{-1} (d

  71. Louigi Addario-Berry, Bruce Reed

    Given a branching random walk, let $M_n$ be the minimum position of any member of the $n$th generation. We calculate $\mathbf{E}M_n$ to within O(1) and prove exponential tail bounds for $\mathbf{P}\{|M_n-\mathbf{E}M_n|>x\}$, under quite general conditions on the branching random walk. In particular, together with work by Bramson [Z. Wahrsch. Verw. Gebiete 45

  72. R. Kehoe, M. Narain, A. Kumar

    As the heaviest known fundamental particle, the top quark has taken a central role in the study of fundamental interactions. Production of top quarks in pairs provides an important probe of strong interactions. The top quark mass is a key fundamental parameter which places a valuable constraint on the Higgs boson mass and electroweak symmetry breaking. Obser

  73. Anatol N. Kirillov, Toshiaki Maeno

    For the root system of type $A$ we introduce and study a certain extension of the quadratic algebra invented by S. Fomin and the first author, to construct a model for the equivariant cohomology ring of the corresponding flag variety. As an application of our construction we describe a generalization of the equivariant Pieri rule for double Schubert polynomi

  74. Hongyi Yao

    The notation of mutually unbiased bases(MUB) was first introduced by Ivanovic to reconstruct density matrixes\cite{Ivanovic}. The subject about how to use MUB to analyze, process, and utilize the information of the second moments between random variables is studied in this paper. In the first part, the mathematical foundation will be built. It will be shown

  75. Margenstern Maurice

    In this paper, we look at the following question. We consider cellular automata in the hyperbolic plane and we consider the global function defined on all possible configurations. Is the injectivity of this function undecidable? The problem was answered positively in the case of the Euclidean plane by Jarkko Kari, in 1994. In the present paper, we give a par

  76. N. Goldman, A. Kubasiak, P. Gaspard, M. Lewenstein

    Nowadays it is experimentally feasible to create artificial, and in particular, non-Abelian gauge potentials for ultracold atoms trapped in optical lattices. Motivated by this fact, we investigate the fundamental properties of an ultracold Fermi gas in a non-Abelian U(2) gauge potential characterized by a \emph{constant} Wilson loop. Under this specific cond

  77. Alexander Shatskiy

    Static (spherically symmetrical) and stationary solutions for wormholes are considered. The visibility horizon, which characterizes the differences between black holes and passing wormholes, is determined in an invariant way. It is shown that the rotation of wormholes does not affect the amount of phantom matter that surrounds them.

  78. Jun-Qing Xia, Xinmin Zhang

    In this paper we perform a global analysis of the constraints on the inflationary parameters in the presence of dynamical dark energy models from the current observations, including the three-year Wilkinson Microwave Anisotropy Probe (WMAP3) data, Boomerang-2K2, CBI, VSA, ACBAR, SDSS LRG, 2dFGRS and ESSENCE (192 sample). We use the analytic description of th

  79. F. Saitta, V. D&#39;Odorico, M. Bruscoli, S. Cristiani

    [Abridged] We present FLO (From Lines to Over-densities), a new technique to reconstruct the hydrogen density field for the Lya forest lines observed in high resolution QSO spectra. The method is based on the hypothesis that the Lya lines arise in the low to intermediate density intergalactic gas and that the Jeans length is the typical size of the Lya absor

  80. Norio Narita, Bun&#39;ei Sato, Osamu Ohshima, Joshua N. Winn

    We present simultaneous photometric and spectroscopic observations of HD 17156b spanning a transit on UT 2007 November 12. This system is of special interest because of its 21-day period (unusually long for a transiting planet) and its high orbital eccentricity of 0.67. By modeling the Rossiter-McLaughlin effect, we find the angle between the sky projections

  81. Mark E. Perel&#39;man, Galina M. Rubinstein, Vitali A. Tatartchenko

    Dendrites formation in the course of crystallization presents very general phenomenon, which is analyzed in details via the example of ice crystals growth in deionized water. Neutral molecules of water on the surface are combined into the double electric layer (DEL) of oriented dipoles; its field reorients approaching dipoles with observable radio-emission i

  82. Tian De Cao

    The high temperature superconductivity in cuprate materials1 has puzzled scientists over twenty years. We must find a new way to understand superconductivity. It is found the spin-charge correlation may dominate the superconductivity2, and we base our judgment upon the features of various superconductors. Thus we presented the idea that superconductivity cou

  83. Claude Bernard, Maarten Golterman, Yigal Shamir

    Even highly improved variants of lattice QCD with staggered fermions show significant violations of taste symmetry at currently accessible lattice spacings. In addition, the &#34;rooting trick&#34; is used in order to simulate with the correct number of light sea quarks, and this makes the lattice theory nonlocal, even though there is good reason to believe

  84. Glenn Merlet

    We analyze the asymptotic behavior of sequences of random variables defined by an initial condition, a stationary and ergodic sequence of random matrices, and an induction formula involving multiplication is the so-called max-plus algebra. This type of recursive sequences are frequently used in applied probability as they model many systems as some queueing

  85. W. F. Chen

    We show that the ambiguity for the Chern-Simons-like term induced from quantum correction in the extended QED should have nothing to do with the approximation on the exact fermionic propagator, contradictory to the claim in Ref.[19]. Further, we investigate the induced Chern-Simons-like term using the original &#39;t Hooft-Veltman dimensional regularization

  86. Jun Zhang

    Take $A$ to be a regular quadratic algebra of global dimension three. We observe that there are examples of $A$ containing a dimension three regular cubic algebra $C$. If $B$ is another dimension three regular quadratic algebra, also containing $C$ as a subalgebra, then we can form the pushout algebra $D$ of the inclusions $i_1:C\hookrightarrow A$ and $i_2:C

  87. Luis H. Gallardo, Olivier Rahavandrainy

    A perfect polynomial over the binary field $\F_2$ is a polynomial $A \in \F_2[x]$ that equals the sum of all its divisors. If $\gcd(A,x^2-x) \neq 1$ then we call $A$ even. The list of all even perfect polynomials over $\F_2$ with at most 3 prime factors in known. The object of this paper is to give the list of all even perfect polynomials over $\F_2$ with fo

  88. Christopher W. Stubbs

    Optical and infrared observations have thus far detected more celestial cataclysms than have been seen in gravity waves (GW). This argues that we should search for gravity wave signatures that correspond to flux variability seen at optical wavelengths, at precisely known positions. There is an unknown time delay between the optical and gravitational transien

  89. Pavlo Pylyavskyy

    We describe the rank 3 Temperley-Lieb-Martin algebras in terms of Kuperberg&#39;s A_2-webs. We define consistent labelings of webs, and use them to describe the coefficients of decompositions into irreducible webs. We introduce web immanants, inspired by Temperley-Lieb immanants of Rhoades and Skandera. We show that web immanants are positive when evaluated

  90. Bill Rosgen

    Distinguishing logarithmic depth quantum circuits on mixed states is shown to be complete for QIP, the class of problems having quantum interactive proof systems. Circuits in this model can represent arbitrary quantum processes, and thus this result has implications for the verification of implementations of quantum algorithms. The distinguishability problem

  91. David Chadwick

    This paper documents the formation of the European Spreadsheet Risks Interest Group (EuSpRIG www.eusprig.org) and outlines some of the research undertaken and reported upon by interested parties in EuSpRIG publications

  92. P. Pedram, S. Jalalzadeh

    We investigate $(n+1)$--dimensional cosmology with varying speed of light. After solving corresponding Wheeler-DeWitt equation, we obtain exact solutions in both classical and quantum levels for ($c $--$Λ$)--dominated Universe. We then construct the ``canonical&#39;&#39; wave packets which exhibit a good classical and quantum correspondence. We show that arb

  93. S. Yakowitz, L. Gyorfi, J. Kieffer, G. Morvai

    Let $\{(X_i,Y_i)\}$ be a stationary ergodic time series with $(X,Y)$ values in the product space $\R^d\bigotimes \R .$ This study offers what is believed to be the first strongly consistent (with respect to pointwise, least-squares, and uniform distance) algorithm for inferring $m(x)=E[Y_0|X_0=x]$ under the presumption that $m(x)$ is uniformly Lipschitz cont

  94. Grenville J. Croll

    Spreadsheet audit and review procedures are an essential part of almost all City of London financial transactions. Structured processes are used to discover errors in large financial spreadsheets underpinning major transactions of all types. Serious errors are routinely found and are fed back to model development teams generally under conditions of extreme t

  95. Ruitian Lang, Peter W. Shor

    A family of high rate quantum error correcting codes adapted to the amplitude damping channel is presented. These codes are nonadditive and exploit self-complementarity structure to correct all first-order errors. Their rates can be higher than 1/2. The recovery operations of these codes can be generated by a simple algorithm and have a projection nature, wh

  96. A. T. Altyntsev, G. D. Fleishman, G. -L. Huang, V. F. Melnikov

    Theoretical and experimental study of fast electron beams attracts a lot of attention in the astrophysics and laboratory. In the case of solar flares the problem of reliable beam detection and diagnostics is of exceptional importance. This paper explores the fact that the electron beams moving oblique to the magnetic field or along the field with some angula

  97. Qiuping A. Wang

    After the justification of the maximum entropy approach for equilibrium thermodynamic system, and of a maximum path entropy algorithm for nonequilibrium thermodynamic systems by virtue of the principle of virtual work, we present in this paper another application of the principle to thermodynamic systems out of equilibrium. Unlike the justification of maximu

  98. A. W. Rushforth, K. Výborný, C. S. King, K. W. Edmonds

    We present details of our experimental and theoretical study of the components of the anisotropic magnetoresistance (AMR) in (Ga,Mn)As. We develop experimental methods to yield directly the non-crystalline and crystalline AMR components which are then independently analyzed. These methods are used to explore the unusual phenomenology of the AMR in ultra thin

  99. Pietro Caputo, Paolo Dai Pra, Gustavo Posta

    We develop a method, based on a Bochner-type identity, to obtain estimates on the exponential rate of decay of the relative entropy from equilibrium of Markov processes in discrete settings. When this method applies the relative entropy decays in a convex way. The method is shown to be rather powerful when applied to a class of birth and death processes. We

  100. Danil Doubochinski, Jonathan Tennenbaum

    The present paper presents a new general conception of interaction between physical systems, differing significantly from that of both classical physics and quantum physics as generally understood. We believe this conception could provide the basis for a coherent understanding of several classes of natural phenomena that until now have been studied only in a