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November 2010 arXiv papers — page 38

Showing 3,7013,800 of 6,505 papers

  1. P. V. Buividovich, M. I. Polikarpov

    We study the electric conductivity of the vacuum of quenched SU(2) lattice gauge theory induced by the magnetic field B as a function of the bare quark mass m. The conductivity grows as the quark mass decreases. Simplest power-like fit indicates that the conductivity behaves as B/sqrt(m). We discuss the implications of this result for dilepton angular distri

  2. Eric Bahuaud

    In this paper we prove that given a smoothly conformally compact metric there is a short-time solution to the Ricci flow that remains smoothly conformally compact. We adapt recent results of Schnürer, Schulze and Simon to prove a stability result for conformally compact Einstein metrics sufficiently close to the hyperbolic metric.

  3. V. V. Bavula

    For the algebra $\mI_1= K<x, \frac{d}{dx}, \int>$ of polynomial integro-differential operators over a field $K$ of characteristic zero, a classification of simple modules is given. It is proved that $\mI_1$ is a left and right coherent algebra. The {\em Strong Compact-Fredholm Alternative} is proved for $\mI_1$. The endomorphism algebra of each simple $\mI_1

  4. Valter Moretti, Nicola Pinamonti

    Tunneling processes through black hole horizons have recently been investigated in the framework of WKB theory discovering interesting interplay with the Hawking radiation. In this paper we instead adopt the point of view proper of QFT in curved spacetime, namely, we use a suitable scaling limit technique to obtain the leading order of the correlation functi

  5. Fabien Trihan, Christian Wuthrich

    We prove the $p$-parity conjecture for elliptic curves over global fields of characteristic $p > 3$. We also present partial results on the $\ell$-parity conjecture for primes $\ell \neq p$.

  6. Matthias R Gaberdiel, Rajesh Gopakumar

    We propose a duality between the 2d W_N minimal models in the large N &#39;t Hooft limit, and a family of higher spin theories on AdS_3. The 2d CFTs can be described as WZW coset models, and include, for N=2, the usual Virasoro unitary series. The dual bulk theory contains, in addition to the massless higher spin fields, two complex scalars (of equal mass).

  7. Katherine L. Brown, Suvabrata De, Vivien M. Kendon, William J. Munro

    We consider simulating the BCS Hamiltonian, a model of low temperature superconductivity, on a quantum computer. In particular we consider conducting the simulation on the qubus quantum computer, which uses a continuous variable ancilla to generate interactions between qubits. We demonstrate an O(N^3) improvement over previous work conducted on an NMR comput

  8. Giovanni De Ninno, Duccio Fanelli

    We consider a paradigmatic model describing the one-dimensional motion of $N$ rotators coupled through a mean-field interaction, and subject to the perturbation of an external magnetic field. The latter is shown to significantly alter the system behaviour, driving the emergence of ensemble inequivalence in the out-of-equilibrium phase, as signalled by a nega

  9. Jian Ma, Xiaoguang Wang, C. P. Sun, Franco Nori

    This paper reviews quantum spin squeezing, which characterizes the sensitivity of a state with respect to an SU(2) rotation, and is significant for both entanglement detection and high-precision metrology. We first present various definitions of spin squeezing parameters, explain their origin and properties for typical states, and then discuss spin-squeezed

  10. Rafał M. Łochowski, Piotr Miłoś

    In the paper we introduce the truncated variation, upward truncated variation and downward truncated variation. These are closely related to the total variation but are well-defined even if the latter is infinite. Our aim is to explore their feasibility to studies of stochastic processes. We concentrate on a Brownian motion with drift for which we prove the

  11. Andrew J Penner

    In this paper we present a fully relativistic study of axisymmetric magnetohydrodynamic Bondi--Hoyle accretion onto a moving Kerr black hole. The equations of general relativistic magnetohydrodynamics are solved using high resolution shock capturing methods. In this treatment we consider the ideal MHD limit. The parameters of interest in this study are the a

  12. Ian Pratt-Hartmann

    This paper undertakes a re-examination of Sir William Hamilton's doctrine of the quantification of the predicate. Hamilton's doctrine comprises two theses. First, the predicates of traditional syllogistic sentence-forms contain implicit existential quantifiers, so that, for example, "All p are q" is to be understood as "All p are some q". Second, these impli

  13. C. Marat Reyes

    Stringent limits on the Myers-Pospelov timelike parameter for photons $ξ<10^{-15}$ coming from astrophysical tests suggest exploring more general preferred backgrounds, such as spacelike and lightlike. We take some steps in this direction. We allow the external four vector $n$ characterizing the Lorentz symmetry breaking to have arbitrary directions in space

  14. G. R. Farrar, R. Mackeprang, D. Milstead, J. P. Roberts

    We reinterpret the generic CDF charged massive particle limit to obtain a limit on the mass of a stable or long-lived gluino. Various sources of uncertainty are examined. The $R$-hadron spectrum and scattering cross sections are modeled based on known low-energy hadron physics and the resultant uncertainties are quantified and found to be small compared to u

  15. Alejandro Perez, Daniele Pranzetti

    We study the classical field theoretical formulation of static generic isolated horizons in a manifestly SU(2) invariant formulation. We show that the usual classical description requires revision in the non-static case due to the breaking of diffeomorphism invariance at the horizon leading to the non conservation of the usual pre-symplectic structure. We ar

  16. Marcel Nutz, H. Mete Soner

    We consider dynamic sublinear expectations (i.e., time-consistent coherent risk measures) whose scenario sets consist of singular measures corresponding to a general form of volatility uncertainty. We derive a càdlàg nonlinear martingale which is also the value process of a superhedging problem. The superhedging strategy is obtained from a representation sim

  17. Y. M. Beltukov, D. A. Parshin

    We propose a random matrix approach to describe vibrational excitations in disordered systems. The dynamical matrix M is taken in the form M=AA^T where A is some real (not generally symmetric) random matrix. It guaranties that M is a positive definite matrix which is necessary for mechanical stability of the system. We built matrix A on a simple cubic lattic

  18. Zhi-zhong Xing

    Recent neutrino oscillation data hint that the smallest neutrino mixing angle theta_{13} is possible to lie in the range 5^\circ \lesssim θ_{13} \lesssim 12^\circ. We show that reasonable perturbations to the democratic mixing pattern, which is geometrically related to the tri-bimaximal mixing pattern through an equal shift θ_* \simeq 9.7^\circ of two large

  19. S. Nawar, A. L. Tadross, J. S. Mikhail, A. B. Morcos

    From photoelectric observations of night sky brightness carried out at Abu-Simbel, Asaad et al. (1979) have obtained values of integrated starlight brightness at different Galactic latitudes. These data have been used in the present work to obtain the brightness and color of the integrated starlight at North and South Celestial, Ecliptic and Galactic Poles.

  20. Pieter Moree

    If the equation of the title has an integer solution with k>=2, then m>10^{10^6}. Leo Moser showed this in 1953 by amazingly elementary methods. With the hindsight of more than 50 years his proof can be somewhat simplified. We give a further proof showing that Moser's result can be derived from a von Staudt-Clausen type theorem. Based on more recent developm

  21. George Siopsis, Jason Therrien, Suphot Musiri

    We discuss holographic superconductors in an arbitrary dimension whose dual black holes have scalar hair of mass near the Breitenlohner-Freedman bound. We concentrate on low temperatures in the probe limit. We show analytically that when the bound is saturated, the condensate diverges at low temperatures as $|\ln T|^δ$, where $δ$ depends on the dimension. Th

  22. Tuomas Hytönen, Suile Liu, Dachun Yang, Dongyong Yang

    Let $({\mathcal X}, d, μ)$ be a separable metric measure space satisfying the known upper doubling condition, the geometrical doubling condition and the non-atomic condition that $μ(\{x\})=0$ for all $x\in{\mathcal X}$. In this paper, we show that the boundedness of a Calderón-Zygmund operator $T$ on $L^2(μ)$ is equivalent to that of $T$ on $L^p(μ)$ for some

  23. A. L. Tadross, M. A. Hanna, N. S. Awadalla

    In this paper, we study the characteristics and physical properties of the young open cluster Pleiades (NGC 1432; M45; Melotte 22; Seven Sisters) using Near Infra Red, JHK pass bands. Our results have been compared with those found in optical, UBV, newly observations. The membership validity of some variable binary stars, which are Located in Taurus constell

  24. Michaël Garcia, Stefano Berti, Philippe Peyla, Salima Rafaï

    Swimming at a micrometer scale demands particular strategies. Indeed when inertia is negligible as compared to viscous forces (i.e. Reynolds number $Re$ is lower than unity), hydrodynamics equations are reversible in time. To achieve propulsion at low Reynolds number, swimmers must then deform in a way that is not invariant under time reversal. Here, we inve

  25. O. J. Lipscombe, G. F. Chen, Chen Fang, T. G. Perring

    We use inelastic neutron scattering to show that the spin waves in the iron chalcogenide Fe$_{1.05}$Te display novel dispersion clearly different from those in the related iron pnictide systems. By fitting the spin waves to a Heisenberg Hamiltonian, we extract magnetic exchange couplings that are dramatically different from both predictions by density functi

  26. Klaas Vantournhout, Thomas Neff, Hans Feldmeier, Natalie Jachowicz

    We present a novel method to study the dynamics of bulk fermion systems such as the neutron-star crust. By introducing periodic boundary conditions into Fermionic Molecular Dynamics, it becomes possible to examine the long-range many-body correlations induced by antisymmetrisation in bulk fermion systems. The presented technique treats the spins and the ferm

  27. Waldemar Martens

    We calculate the two-loop matching corrections for the gauge couplings at the Grand Unification scale in a general framework that aims at making as few assumptions on the underlying Grand Unified Theory (GUT) as possible. In this paper we present an intermediate result that is general enough to be applied to the Georgi-Glashow SU(5) as a &#34;toy model&#34;.

  28. Otgonbayar Uuye

    Category of fibrant objects is a convenient framework to do homotopy theory, introduced and developed by Ken Brown. In this paper, we apply it to the category of C^{*}-algebras. In particular, we get a unified treatment of (ordinary) homotopy theory for C^{*}-algebras, KK-theory and E-theory, as all of these can be expressed as the homotopy category of a cat

  29. Yacine Chitour, Petri Kokkonen

    In this paper, we consider two cases of rolling of one smooth connected complete Riemannian manifold $(M,g)$ onto another one $(\hM,\hg)$ of equal dimension $n\geq 2$. The rolling problem $(NS)$ corresponds to the situation where there is no relative spin (or twist) of one manifold with respect to the other one. As for the rolling problem $(R)$, there is no

  30. Wolfgang Bertram, Pierre Bieliavsky

    We investigate a special kind of contraction of symmetric spaces (respectively, of Lie triple systems), called homotopy. In this first part of a series of two papers we construct such contractions for classical symmetric spaces in an elementary way by using associative algebras with several involutions. This construction shows a remarkable duality between th

  31. Boris P. Lavrov, Andrey S. Mikhailov, Ivan S. Umrikhin

    New sets of experimental wavenumber values for triplet-triplet rovibronic transitions of $H_2$ and $D_2$ for visible part of spectrum ($400 ÷700$ nm) have been obtained. The digital intensity registration providing a linear response of the detector gave us the opportunity of digital deconvolution of the recorded line profiles. For line centers that made it p

  32. B. Boisseau

    We consider the massive scalar-tensor theory in the Jordan frame $F(Φ) =K^{2}Φ^2$ and $U(Φ) =(1/2)m^{2}Φ^2$, where $F(Φ)$ corresponds to a constant Brans-Dicke parameter $ω_{BD}=1/4K^2$. The constraint of the Solar System experiments is $K^2<(1/400)^2$. For dustlike matter in a spatially flat homogeneous isotropic universe, we reduce the equations of motion

  33. Mohammad Salehi Fashami, Kuntal Roy, Jayasimha Atulasimha, Supriyo Bandyopadhyay

    It has been recently shown that multiferroic logic - where logic bits are encoded in the magnetization orientation of a nanoscale magnetostrictive layer elastically coupled to a piezoelectric layer - can be Bennett clocked with small electrostatic potentials of few tens of mV applied to the piezoelectric layer. The potential generates stress in the magnetost

  34. Samuel D. McDermott, Hai-Bo Yu, Kathryn M. Zurek

    We consider current observational constraints on the electromagnetic charge of dark matter. The velocity dependence of the scattering cross-section through the photon gives rise to qualitatively different constraints than standard dark matter scattering through massive force carriers. In particular, recombination epoch observations of dark matter density per

  35. Tadahito Nakajima, Yukiko Ohtake, Kenji Suzuki

    We consider the noncommutative deformation of the Sakai--Sugimoto model at finite temperature and finite baryon chemical potential. The space noncommutativity is possible to have an influence on the flavor dynamics of the QCD. The critical temperature and critical value of the chemical potential are modified by the space noncommutativity. The influence of th

  36. Simon Badger, Benedikt Biedermann, Peter Uwer

    We present a computer library for the numerical evaluation of colour-ordered n-gluon amplitudes at one-loop order in pure Yang-Mills theory. The library uses the recently developed technique of generalised unitarity. Running in double precision the library yields reliable results for up to 14 gluons with only a small fraction of events requiring a re-evaluat

  37. Zhonghua Li

    We give new proofs of two functional relations for the alternating analogues of Tornheim&#39;s double zeta function. Using the functional relations, we give new proofs of some evaluation formulas found by H. Tsumura for these alternating series.

  38. Zining Cao

    In this paper, we show that theory of processes can be reduced to the theory of spatial logic. Firstly, we propose a spatial logic SL for higher order pi-calculus, and give an inference system of SL. The soundness and incompleteness of SL are proved. Furthermore, we show that the structure congruence relation and one-step transition relation can be described

  39. Manuel Bodirsky, Michael Pinsker

    Schaefer&#39;s theorem is a complexity classification result for so-called Boolean constraint satisfaction problems: it states that every Boolean constraint satisfaction problem is either contained in one out of six classes and can be solved in polynomial time, or is NP-complete. We present an analog of this dichotomy result for the propositional logic of gr

  40. Vladimir I. Danilov, Alexander V. Karzanov, Gleb A. Koshevoy

    A Condorcet domain (CD) is a collection of linear orders on a set of candidates satisfying the following property: for any choice of preferences of voters from this collection, a simple majority rule does not yield cycles. We propose a method of constructing &#34;large&#34; CDs by use of rhombus tiling diagrams and explain that this method unifies several co

  41. Hong Van Le

    We develop a method to construct elusive functions using techniques of commutative algebra and algebraic geometry. The key notions of this method are elusive subsets and evaluation mappings. We also develop the effective elimination theory combined with algebraic number field theory in order to construct concrete points outside the image of a polynomial mapp

  42. Tomáš Dohnal, Michael Plum, Wolfgang Reichel

    We consider the nonlinear Schrödinger equation $(-Δ+V(x))u = Γ(x) |u|^{p-1}u$, $x\in \R^n$ with $V(x) = V_1(x) χ_{\{x_1>0\}}(x)+V_2(x) χ_{\{x_1<0\}}(x)$ and $Γ(x) = Γ_1(x) χ_{\{x_1>0\}}(x)+Γ_2(x) χ_{\{x_1<0\}}(x)$ and with $V_1, V_2, Γ_1, Γ_2$ periodic in each coordinate direction. This problem describes the interface of two periodic media, e.g. photonic cry

  43. Ryan Woodard, Didier Sornette, Maxim Fedorovsky

    This is the third installment of the Financial Bubble Experiment. Here we provide the digital fingerprint of an electronic document in which we identify 27 bubbles in 27 different global assets; for 25 of these assets, we present windows of dates of the most likely ending time of each bubble. We will provide that document of the original analysis on 2 May 20

  44. Zhouyun Wu, Aiping Huang, Haojie Zhou, Cunqing Hua

    Interference matrix (IM) has been widely used in frequency planning/optimization of cellular systems because it describes the interaction between any two cells. IM is generated from the source data gathered from the cellular system, either mobile measurement reports (MMRs) or drive test (DT) records. IM accuracy is not satisfactory since neither MMRs nor DT

  45. Martin Kilian, Martin Ulrich Schmidt, Nicholas Schmitt

    We present a deformation for constant mean curvature tori in the 3-sphere. We show that the moduli space of equivariant constant mean curvature tori in the 3-sphere is connected, and we classify the minimal, the embedded, and the Alexandrov embedded tori therein. We conclude with an instability result.

  46. Christoph Nölle

    I construct solutions to the heterotic supergravity BPS-equations on products of Minkowski space with a non-symmetric coset. All of the bosonic fields are homogeneous and non-vanishing, the dilaton being a linear function on the non-compact part of spacetime.

  47. Wahb Ettoumi, Marie-Christine Firpo

    In this article, several aspects of the dynamics of a toy model for longrange Hamiltonian systems are tackled focusing on linearly unstable unmagnetized (i.e. force-free) cold equilibria states of the Hamiltonian Mean Field (HMF). For special cases, exact finite-N linear growth rates have been exhibited, including, in some spatially inhomogeneous case, finit

  48. Thomas Neff

    The radiative capture cross sections for the 3He(alpha,gamma)7Be and 3H(alpha,gamma)7Li reactions are calculated in the fully microscopic fermionic molecular dynamics approach using a realistic effective interaction that reproduces the nucleon-nucleon scattering data. At large distances bound and scattering states are described by antisymmetrized products of

  49. Sergey Dashkovskiy, Michael Kosmykov, Andrii Mironchenko, Lars Naujok

    In this paper we consider input-to-state stability (ISS) of impulsive control systems with and without time-delays. We prove that if the time-delay system possesses an exponential Lyapunov-Razumikhin function or an exponential Lyapunov-Krasovskii functional, then the system is uniformly ISS provided that the average dwell-time condition is satisfied. Then, w

  50. Giulio Biroli, Bryan Clark, Laura Foini, Francesco Zamponi

    We investigate the constraints on the superfluid fraction of an amorphous solid following from an upper bound derived by Leggett. In order to accomplish this, we use as input density profiles generated for amorphous solids in a variety of different manners including by investigating Gaussian fluctuations around classical results. These rough estimates sugges

  51. Daniel Brüderle, Mihai A. Petrovici, Bernhard Vogginger, Matthias Ehrlich

    In this paper we present a methodological framework that meets novel requirements emerging from upcoming types of accelerated and highly configurable neuromorphic hardware systems. We describe in detail a device with 45 million programmable and dynamic synapses that is currently under development, and we sketch the conceptual challenges that arise from takin

  52. A. Cieplý, E. Friedman, A. Gal, V. Krejčiřík

    1s(Lambda) hypernuclear formation rates in stopped K- reactions on several p-shell targets are derived from hypernuclear formation spectra measured recently by the FINUDA Collaboration and are compared with calculated 1s(Lambda) formation rates based on a KbarN coupled channels chiral model. The calculated rates are about 15% of the derived rates, depending

  53. Charles Favre, Elizabeth Wulcan

    We compute all dynamical degrees of monomial maps by interpreting them as mixed volumes of polytopes. By exploiting further the isomorphism between the polytope algebra of P. McMullen and the universal cohomology of complete toric varieties, we construct invariant positive cohomology classes when the dynamical degrees have no resonance.

  54. Dima Bolmatov, Chung-Yu Mou

    The electronic transport properties of graphene-based superlattice structures are investigated. A graphene-based modulation-doped superlattice structure geometry is proposed and consist of periodically arranged alternate layers: InAs/graphene/GaAs/graphene/GaSb. Undoped graphene/GaAs/graphene structure displays relatively high conductance and enhanced mobili

  55. Debashis Gangopadhyay, Sourav Sen Choudhury

    It is known that dynamical solutions of the $k$-essence equation of motion change the metric for the perturbations around these solutions and the perturbations propagate in an emergent spacetime with metric $\tilde G^{μν}$ different from the gravitational metric $g^{μν}$. We show that for observers travelling with the perturbations, there exist field configu

  56. P. Siegle, I. Goychuk, P. Hanggi

    The Fractional Langevin Equation (FLE) describes a non-Markovian Generalized Brownian Motion with long time persistence (superdiffusion), or anti-persistence (subdiffusion) of both velocity-velocity correlations, and position increments. It presents a case of the Generalized Langevin Equation (GLE) with a singular power law memory kernel. We propose and nume

  57. Sebastien Boucksom, Tommaso De Fernex, Charles Favre

    We introduce a notion of volume of a normal isolated singularity that generalizes Wahl's characteristic number of surface singularities to arbitrary dimensions. We prove a basic monotonicity property of this volume under finite morphisms. We draw several consequences regarding the existence of non-invertible finite endomorphisms fixing an isolated singularit

  58. Pengfei Zhang

    Let M be a closed manifold and f be a diffeomorphism on M. We show that if f has a nontrivial dominated splitting TM=E\oplus F, then f can not be minimal. The proof mainly use Mane's argument and Liao's selecting lemma.

  59. Giuseppe F. Italiano, Piotr Sankowski

    In this paper we study minimum cut and maximum flow problems on planar graphs, both in static and in dynamic settings. First, we present an algorithm that given an undirected planar graph computes the minimum cut between any two given vertices in O(n log log n) time. Second, we show how to achieve the same O(n log log n) bound for the problem of computing ma

  60. Elise Jennings, Carlton M. Baugh, Silvia Pascoli

    Future galaxy surveys hope to distinguish between the dark energy and modified gravity scenarios for the accelerating expansion of the Universe using the distortion of clustering in redshift space. The aim is to model the form and size of the distortion to infer the rate at which large scale structure grows. We test this hypothesis and assess the performance

  61. Eunghyun Lee

    This paper presents the exact expressions of the transition probabilities of some non-determinantal Bethe ansatz solvable interacting particle systems: the two-sided PushASEP, the asymmetric avalanche process and the asymmetric zero range process. The time integrated currents of the asymmetric avalanche process and the asymmetric zero range process are immed

  62. Daijiro Suematsu, Takashi Toma

    The existence of an anomalous U(1) symmetry is shown to play a crucial role in the supersymmetric radiative seesaw model for neutrino masses. It explains the smallness of some couplings related to neutrino mass generation in a favorable way in addition to cause the hierarchical structure of Yukawa couplings of quarks and leptons. If it is spontaneously broke

  63. Sushant G. Ghosh, L. P. Singh

    A magnetic-monopole solution of a non-Abelian gauge theory as proposed by &#39;t Hooft and Polyakov is studied in the Vaidya spacetime. We find that the solutions of Einstein equations generates a geometry of the Bonnor-Vaidya corresponding to magnetically charged null fluid with Higgs field contributing a cosmological term. In the absence of the scalar fiel

  64. S. V. Bolokhov, K. A. Bronnikov, S. G. Rubin

    The Higgs boson of the Standard model is described by a set of off-diagonal components of the multidimensional metric tensor, as well as the gauge fields. In the low-energy limit, the basic properties of the Higgs boson are reproduced, including the shape of the potential and interactions with the gauge fields of the electroweak part of the Standard model.

  65. Xiaolin Luo, Pavel V. Shevchenko

    It is a well known fact that recovery rates tend to go down when the number of defaults goes up in economic downturns. We demonstrate how the loss given default model with the default and recovery dependent via the latent systematic risk factor can be estimated using Bayesian inference methodology and Markov chain Monte Carlo method. This approach is very co

  66. Changlong Zhong

    We prove that there is a map from Bloch&#39;s cycle complex to Kato&#39;s complex of Milnor K-theory, which induces a quasi-isomorphism from étale sheafified cycle complex to the Gersten complex of logarithmic de Rham--Witt sheaves. Next we show that the truncation of Bloch&#39;s cycle complex at -3 is quasi-isomorphic to Spiess&#39; dualizing complex.

  67. Jian-Rong Zhang, Ming-Qiu Huang

    The mass of $P$-wave $cs$-scalar-diquark $\bar{c}\bar{s}$-scalar-antidiquark state is computed in the framework of QCD sum rules. The result $4.69\pm0.36{GeV}$ is in good agreement with the experimental value of Y(4660) but higher than Y(4260)&#39;s, which supports the $P$-wave $[cs][\bar{c}\bar{s}]$ configuration for Y(4660) while disfavors the interpretati

  68. Marco Pedro Ramirez Tachiquin

    The paper studies a particular class of analytic solutions for the Generalized Ohm&#39;s Law, approached by means of the so called formal powers of the Pseudoanalytic Function Theory. The reader will find a description of the electrical current distributions inside bounded domains, within inhomogeneous media, and their corresponding electric potentials near

  69. Xian-Jun Zuo

    We study striped morphologies induced by magnetic impurities in d-wave superconductors (DSCs) near optimal doping by self-consistently solving the Bogoliubov-de Gennes equations based on the $t-t^{\prime }-U-V$ model. For the single impurity case, it is found that the stable ground state is a modulated checkerboard pattern. For the two-impurity case, the str

  70. Thomas Koberda

    In this article we study the space of left- and bi-invariant orderings on a torsion-free nilpotent group $G$. We will show that generally the set of such orderings is equipped with a faithful action of the automorphism group of $G$. We prove a result which allows us to establish the same conclusion when $G$ is assumed to be merely residually torsion-free nil

  71. Vitaliy Kapko, Dmitry V. Matyushov, C. Austen Angell

    The ability of some liquids to vitrify during supercooling is usually seen as a consequence of the rates of crystal nucleation (and/or crystal growth) becoming small- thus a matter of kinetics. However there is evidence, dating back to the empirics of coal briquetting for maximum trucking efficiency, that ellipsoids pack efficiently when disordered. Noting t

  72. Nick Letzepis, Alex Grant, Paul Alexander, David Haley

    We study multipath parameter estimation from orthogonal frequency division multiplex signals transmitted over doubly dispersive mobile radio channels. We are interested in cases where the transmission is long enough to suffer time selectivity, but short enough such that the time variation can be accurately modeled as depending only on per-tap linear phase va

  73. M. Aparicio Alcalde, B. M. Pimentel

    The full Dicke model describes a system of $N$ identical two level-atoms coupled to a single-mode quantized bosonic field. The model considers rotating and counter-rotating coupling terms between the atoms and the bosonic field, with coupling constants $g_1$ and $g_2$, for each one of the coupling terms, respectively. We study finite temperature properties o

  74. Cihan Tepedelenlioglu, Sivaraman Dasarathan

    A distributed detection scheme where the sensors transmit with constant modulus signals over a Gaussian multiple access channel is considered. The deflection coefficient of the proposed scheme is shown to depend on the characteristic function of the sensing noise and the error exponent for the system is derived using large deviation theory. Optimization of t

  75. Jim Pitman, Nathan Ross

    This article contains both a point process and a sequential description of the greatest convex minorant of Brownian motion on a finite interval. We use these descriptions to provide new analysis of various features of the convex minorant such as the set of times where the Brownian motion meets its minorant. The equivalence of the these descriptions is non-tr

  76. F. R. N. C. Maia, C. Yang, S. Marchesini

    Ultrafast nanocrystallography has the potential to revolutionize biology by enabling structural elucidation of proteins for which it is possible to grow crystals with 10 or fewer unit cells on the side. The success of nanocrystallography depends on robust orientation-determination procedures that allow us to average diffraction data from multiple nanocrystal

  77. A. V. Andreev, Steven A. Kivelson, B. Spivak

    We develop a hydrodynamic description of the resistivity and magnetoresistance of an electron liquid in a smooth disorder potential. This approach is valid when the electron-electron scattering length is sufficiently short. In a broad range of temperatures, the dissipation is dominated by heat fluxes in the electron fluid, and the resistivity is inversely pr

  78. J. D. Teufel, D. Li, M. S. Allman, K. Cicak

    Demonstrating and exploiting the quantum nature of larger, more macroscopic mechanical objects would help us to directly investigate the limitations of quantum-based measurements and quantum information protocols, as well as test long standing questions about macroscopic quantum coherence. The field of cavity opto- and electro-mechanics, in which a mechanica

  79. Scott W. McIntosh, Robert J. Leamon, Bart De Pontieu

    We analyze a large, complex equatorial coronal hole (ECH) and its immediate surroundings with a focus on the roots of the fast solar wind. We start by demonstrating that our ECH is indeed a source of the fast solar wind at 1AU by examining in situ plasma measurements in conjunction with recently developed measures of magnetic conditions of the photosphere, i

  80. G. L. Klimchitskaya, C. Romero

    We discuss possibility to obtain stronger constraints on non-Newtonian gravity from measuring the gradient of the Casimir force between a cylinder and a plate. Exact analytical expression for the Yukawa-type force in a cylinder-plate configuration is obtained, as well as its asymptotic expansions. The gravitational force is compared with the Casimir force ac

  81. Roberto Onofrio

    We explore the consequences of the mass generation due to the Higgs field in strong gravity astrophysical environments. The vacuum expectation value of the Higgs field is predicted to depend on the curvature of spacetime, potentially giving rise to peculiar spectroscopic shifts, named hereafter &#34;Higgs shifts.&#34; Higgs shifts could be searched through d

  82. Ankur Mani, Asuman Ozdaglar, Alex, Pentland

    In this paper we study the generalized version of weighted matching in bipartite networks. Consider a weighted matching in a bipartite network in which the nodes derive value from the split of the matching edge assigned to them if they are matched. The value a node derives from the split depends both on the split as well as the partner the node is matched to

  83. Christian Borgs, Jennifer T. Chayes, Prasad Tetali

    We study two widely used algorithms for the Potts model on rectangular subsets of the hypercubic lattice Z^d - heat bath dynamics and the Swendsen-Wang algorithm - and prove that, under certain circumstances, the mixing in these algorithms is torpid or slow. In particular, we show that for heat bath dynamics throughout the region of phase coexistence, and fo

  84. Alberto Nicolis

    We derive the Noether currents and charges associated with an internal galilean invariance---a symmetry recently postulated in the context of so-called galileon theories. Along the way we clarify the physical interpretation of the Noether charges associated with ordinary Galileo- and Lorentz-boosts.

  85. Yuriy V. Pershin, Massimiliano Di Ventra

    Memory effects are ubiquitous in nature and are particularly relevant at the nanoscale where the dynamical properties of electrons and ions strongly depend on the history of the system, at least within certain time scales. We review here the memory properties of various materials and systems which appear most strikingly in their non-trivial time-dependent re

  86. Eric Lauga

    Locomotion on small scales is dominated by the effects of viscous forces and, as a result, is subject to strong physical and mathematical constraints. Following Purcell&#39;s statement of the scallop theorem which delimitates the types of swimmer designs which are not effective on small scales, we review the different ways the constraints of the theorem can

  87. Warren R. Brown, Mukremin Kilic, Carlos Allende Prieto, Scott J. Kenyon

    We analyze radial velocity observations of the 12 extremely low-mass <0.25 Msol white dwarfs (WDs) in the MMT Hypervelocity Star Survey. Eleven of the 12 WDs are binaries with orbital periods shorter than 14 hours; the one non-variable WD is possibly a pole-on system among our non-kinematically selected targets. Our sample is unique: it is complete in a well

  88. Qi Guo, Shaun Cole, Cedric G. Lacey, Carlton M. Baugh

    We measure the projected cross-correlation between low redshift (z < 0.5) far-IR selected galaxies in the SDP field of the Herschel-ATLAS (H-ATLAS) survey and optically selected galaxies from the Galaxy and Mass Assembly (GAMA) redshift survey. In order to obtain robust correlation functions, we restrict the analysis to a subset of 969 out of 6900 H-ATLAS ga

  89. Warren R. Brown, Mukremin Kilic, Carlos Allende Prieto, Scott J. Kenyon

    We study a complete, colour-selected sample of double-degenerate binary systems containing extremely low mass (ELM) <0.25 Msol white dwarfs (WDs). We show, for the first time, that Milky Way disk ELM WDs have a merger rate of approximately 4 x 10^(-5)/yr due to gravitational wave radiation. The merger end-product depends on the mass ratio of the binary. The

  90. D. S. L. Abergel, Tapash Chakraborty

    We describe the gated bilayer graphene system when it is subjected to intense terahertz frequency electromagnetic radiation. We examine the electron band structure and density of states via exact diagonalization methods within Floquet theory. We find that dynamical states are induced which lead to modification of the band structure. We first examine the situ

  91. Moein Mosleh, Rik J. Williams, Marijn Franx, Mariska Kriek

    We study the evolution of the size - stellar mass relation for a large spectroscopic sample of galaxies in the GOODs North field up to $z \sim 3.5$. The sizes of the galaxies are measured from $\textit{K}_{s}$-band images (corresponding to rest-frame optical/NIR) from the Subaru 8m telescope. We reproduce earlier results based on photometric redshifts that t

  92. O. L. Creevey, M. Bazot

    We present two independent methods for studying the global stellar parameter space (mass M, age, initial chemical composition X_0, Z_0) of HD 49933 with seismic data. Using a local minimization and an MCMC algorithm, we obtain consistent results for the determination of the stellar properties: M = 1.1 - 1.2 M_solar, Age ~ 3.0 Gyr, Z_0 ~ 0.008. A description

  93. D. V. Antonov, A. V. Nefediev, J. E. F. T. Ribeiro

    Formation of stable domains filled with strongly correlated coherent quark matter is discussed in general terms and is exemplified further in the framework of the Generalised Nambu-Jona-Lasinio model. It is argued that such domains, if exist in the Universe, appear dark to an external observer.

  94. Bas Janssens

    This PHD thesis is concerned with uncertainty relations in quantum probability theory, state estimation in quantum stochastics, and natural bundles in differential geometry. After some comments on the nature and necessity of decoherence in open systems and its absence in closed ones, we prove sharp, state-independent inequalities reflecting the Heisenberg pr

  95. Anthony M. Cutler

    A polyhedron in Euclidean 3-space is called a regular polyhedron of index 2 if it is combinatorially regular and its geometric symmetry group has index 2 in its combinatorial automorphism group; thus its automorphism group is flag-transitive but its symmetry group has two flag orbits. The present paper completes the classification of finite regular polyhedra

  96. O. L. Creevey, D. Salabert, R. A. Garcia

    Frequency separations used to infer global properties of stars through asteroseismology can change depending on the strength and at what epoch of the stellar cycle the p-mode frequencies are measured. In the Sun these variations have been seen, even though the Sun is a low-activity star. In this paper, we discuss these variations and their impact on the dete

  97. O. L. Creevey, J. Telting, J. A. Blemonte, T. M. Brown

    We present a preliminary spectroscopic analysis of the binary system V577Oph, observed during the summer of 2007 on the 2.6m NOT telescope on La Palma. We have obtained time series spectroscopic observations, which show clear binary motion as well as radial velocity variations due to pulsation in the primary star. By modelling the radial velocities we determ

  98. Jong-Wan Lee, Michael G. Endres, David B. Kaplan, Amy N. Nicholson

    A fundamental constant in systems of unitary fermions is the so-called Bertsch parameter, the ratio of the ground state energy for spin paired unitary fermions to that for free fermions at the same density. I discuss how we computed this parameter as well as the pairing gap using a recently developed lattice construction for unitary fermions, by measuring co

  99. Auguste Aman

    In this paper, we study reflected generalized backward doubly stochastic differential equations driven by Teugels martingales associated with Lévy process (RGBDSDELs, in short) with one continuous barrier. Under uniformly Lipschitz coefficients, we prove existence and uniqueness result by means of the penalization method and the fixed point theorem. As an ap

  100. S. Nawar, A. B. Morcos, A. L. Tadross, J. S. Mikhail

    A search for discontinuity in the sky twilight brightness at different wavelengths and different solar depressions for altitudes 0, 5, 10, 30, 50 & 70 degrees is done. It is found that the logarithmic of difference in the brightness log (I1-I2) of two similar patches lying at solar and anti-solar verticals are not suffering of any discontinuity, when plotted