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April 2009 arXiv papers — page 48

Showing 4,7014,800 of 4,924 papers

  1. G. G. Plunk, S. C. Cowley, A. A. Schekochihin, T. Tatsuno

    Two-dimensional gyrokinetics is a simple paradigm for the study of kinetic magnetised plasma turbulence. In this paper, we present a comprehensive theoretical framework for this turbulence. We study both the inverse and direct cascades (the `dual cascade'), driven by a homogeneous and isotropic random forcing. The key characteristic length of gyrokinetic

  2. Guilherme L. Pimentel, Odylio D. Aguiar, Michael E. Tobar, Joaquim J. Barroso

    By changing from a resonant multimode paradigm to a free mass paradigm for transducers in resonant mass gravitational wave detection, an array of six spheres can achieve a sensitivity response curve competitive with interferometers, being as sensitive as GEO600 and TAMA300 in the 3 to 6 kHz band and more sensitive than LIGO for 50 percent of the 6 to 10 kHz

  3. David S Berman, Daniel C Thompson

    We investigate the recently developed theory of multiple membranes. In particular, we consider open membranes, i.e. the theory defined on a membrane world volume with a boundary. We first restrict our attention to the gauge sector of the theory. We obtain a boundary action from the Chern-Simons terms. Secondly, we consider the addition of certain boundary te

  4. Sergey M. Natanzon

    We expand Topological Field Theory on some special CW-complexes (brane complexes). This Brane Topological Field Theory one-to-one corresponds to infinite dimensional Frobenius Algebras, graduated by CW-complexes of lesser dimension. We define general and regular Hurwitz numbers of brane complexes and prove that they generate Brane Topological Field Theories.

  5. D. V. Ahluwalia

    In the absence of dark matter, the dynamical and kinematical interpretations of the special relativistic spacetime have been and still are the topic of philosophic debate, which whilst fertile, is by and large of little predictive power. This changes dramatically if the debate includes a dark matter candidate in a "non-trivial" extension of the stand

  6. G. V. Dedkov, A. A. Kyasov

    For the first time, we calculate the heating rate, attractive conservative and tangential dissipative fluctuation electromagnetic forces felt by a thick plate moving parallel to a closely spaced another plate in rest using the retarded nonrelativistic approximation of fluctuation electrodynamics. We argue that recently developed relativistic out of equilibri

  7. Rishi Sharma, Ivan Vitev, Ben-Wei Zhang

    We calculate the lowest order charm and beauty parton distribution functions in and fragmentation functions into D and B mesons using the operator definitions of factorized perturbative QCD. In the vacuum, we find the leading corrections that arise from the structure of the final-state hadrons. Quark-antiquark potentials extracted from the lattice are employ

  8. N. H. Barton, A. M. Etheridge, A. Veber

    We investigate a new model for populations evolving in a spatial continuum. This model can be thought of as a spatial version of the Lambda-Fleming-Viot process. It explicitly incorporates both small scale reproduction events and large scale extinction-recolonisation events. The lineages ancestral to a sample from a population evolving according to this mode

  9. Christian Schnell

    Two simple observations are made: (1) If the normal function associated to a Hodge class has a zero locus of positive dimension, then it has a singularity. (2) The intersection cohomology of the dual variety contains the cohomology of the original variety, if the degree of the embedding is large.

  10. David Rydh

    We show that every scheme/algebraic space/stack that is quasi-compact with quasi-finite diagonal can be approximated by a noetherian scheme/algebraic space/stack. More generally, we show that any stack which is etale-locally a global quotient stack can be approximated. Examples of applications are generalizations of Chevalley's, Serre's and Zariski&#

  11. Arif Emre Erkoca, Gouranga C. Nayak, Ina Sarcevic

    We perform detailed study of the Higgs production and decay, when Higgs is emitted from the black holes produced in proton-proton collisions at the Large Hadron Collider. We show that black hole production can significantly enhance the signal for the Higgs search at the LHC. We evaluate rapidity distribution of diphotons and transverse momentum distribution

  12. Victor de Haan

    Two optical fiber Mach-Zehnder interferometers were constructed in an environment with a temperature stabilization of better than 1 mK per day. One interferometer with a length of 12 m optical fiber in each arm with the main direction of the arms perpendicular to each other. Another with a length of 2 m optical fiber in each arm where the main direction of t

  13. Peng Wu, Nihar Jindal

    This paper studies the tradeoff between channel coding and ARQ (automatic repeat request) in Rayleigh block-fading channels. A heavily coded system corresponds to a low transmission rate with few ARQ re-transmissions, whereas lighter coding corresponds to a higher transmitted rate but more re-transmissions. The optimum error probability, where optimum refers

  14. Hugo E. L. Martay, David J. McCabe, Duncan G. England, Melissa E. Friedman

    Calculations relating to two experiments that demonstrate coherent control of preformed rubidium-85 molecules in a magneto-optical trap using ultrafast laser pulses are presented. In the first experiment, it is shown that pre-associated molecules in an incoherent mixture of states can be made to oscillate coherently using a single ultrafast pulse. A mechanis

  15. Bert Wiest

    We prove that the Garside length a braid is equal to a winding-number type invariant of the curve diagram of the braid.

  16. Srikanth K. Iyer, D. Yogeshwaran

    Given two independent Poisson point processes $Φ^{(1)},Φ^{(2)}$ in $R^d$, the continuum AB percolation model is the graph with points of $Φ^{(1)}$ as vertices and with edges between any pair of points for which the intersection of balls of radius $2r$ centred at these points contains at least one point of $Φ^{(2)}$. This is a generalization of the $AB$ perco

  17. Bruno Iochum, Cyril Levy

    Using the Chamseddine--Connes approach of the noncommutative action on spectral triples, we show that there are no tadpoles of any order for compact spin manifolds without boundary, and also consider a case of a chiral boundary condition. Using pseudodifferential techniques, we track zero terms in spectral actions.

  18. Thierry Jecko

    We give a new, short proof of the regularity away from the nuclei of the electronic density of a molecule obtained in [1,2]. The new argument is based on the regularity properties of the Coulomb interactions underlined in [3,4] and on well-known elliptic technics. [1] S. Fournais, M. Hoffmann-Ostenhof, T. Hoffmann-Ostenhof, T. Oe stergaard Soerensen: The ele

  19. Lorenzo Iorio

    We simultaneously integrate in a numerical way the equations of motion of both the Magellanic Clouds (MCs) in MOND, MOG and CDM for -1 <= t <= +1 Gyr to see if, at least in principle, it is possible to discriminate between them (Abridged version).

  20. Sandor Hegyi

    It is argued that black holes and the limit distributions of probability theory share several properties when their entropy and information content are compared. In particular the no-hair theorem, the entropy maximization and holographic bound, and the quantization of entropy of black holes have their respective analogues for stable limit distributions. This

  21. Babette Dobrich, Holger Gies

    We investigate the use of ground-based gravitational-wave interferometers for studies of the strong-field domain of QED. Interferometric measurements of phase velocity shifts induced by quantum fluctuations in magnetic fields can become a sensitive probe for nonlinear self-interactions among macroscopic electromagnetic fields. We identify pulsed magnets as a

  22. Vladimir V. Bytev, Mikhail Yu. Kalmykov, Bernd A. Kniehl

    The differential-reduction algorithm, which allows one to express generalized hypergeometric functions with parameters of arbitrary values in terms of such functions with parameters whose values differ from the original ones by integers, is discussed in the context of evaluating Feynman diagrams. Where this is possible, we compare our results with those obta

  23. D. Obreschkow, S. Rawlings

    We use a pressure-based model for splitting cold hydrogen into its atomic (HI) and molecular (H2)components to tackle the co-evolution of HI, H2, and star formation rates (SFR) in ~3e7 simulated galaxies in the Millennium simulation. The main prediction is that galaxies contained similar amounts of HI at redshift z=1-5 than today, but substantially more H2,

  24. Clotilde Fermanian-Kammerer, Vidian Rousse

    In this article we focus on a semiclassical Schrödinger equation with matrix-valued potential presenting a symmetric conjoint crossing of three eigenvalues. The potential we consider is well-known in the chemical literature as a pseudo Jahn-Teller potential. We analyze the energy transfers which occur between the three modes in terms of Wigner measures.

  25. B. M. Rodriguez-Lara, I. Ricardez-Vargas

    Using a scheme based on a Mach-Zehnder interferometer, we propose an analysis of the superposition of polarized laser beams at a given angle. The focus of our study is the spatially varying polarization state of the resulting field, also known as a polarization grating, generated by this setup. Our proposal combines a theoretical description of the resulting

  26. Allan P. Fordy, Bethany Marsh

    We consider quivers/skew-symmetric matrices under the action of mutation (in the cluster algebra sense). We classify those which are isomorphic to their own mutation via a cycle permuting all the vertices, and give families of quivers which have higher periodicity. The periodicity means that sequences given by recurrence relations arise in a natural way from

  27. Farook Rahaman, Mubasher Jamil, Kaushik Chakraborty

    Electron is modeled as a spherically symmetric charged perfect fluid distribution of matter. The existing model is extended assuming a matter source that is characterized by quadratic EoS in the context of general theory of relativity. For the suitable choices of the parameters, our charged fluid models almost satisfy the physical properties of electron.

  28. Antonio De Felice, Christophe Ringeval

    We derive exact solutions of the seven-dimensional Einstein-Maxwell equations for a spacetime exhibiting Poincare invariance along four-dimensions and spherical symmetry in the extra-dimensions. Such topology generically arises in the context of braneworld models. Our solutions generalise previous results on Ricci-flat spacetimes admitting the two-sphere and

  29. Gene Abrams, Kulumani M. Rangaswamy

    If $E$ is a not-necessarily row-finite graph, such that each vertex of $E$ emits at most countably many edges, then a {\it desingularization} $F$ of $E$ can be constructed (see e.g. (1) G. Abrams, G. Aranda Pino, Leavitt path algebras of arbitrary graphs, Houston J. Math 34(2) (2008), 423-442, or (2) I. Raeburn, &#34;Graph algebras&#34;. CBMS Regional Confer

  30. Thomas Leistner, Pawel Nurowski

    We present conformal structures in signature (3,2) for which the holonomy of the Fefferman-Graham ambient metric is equal to the non-compact exceptional Lie group G_{2(2)}. We write down the resulting 8-parameter family of G_{2(2)}-metrics in dimension seven explicitly in an appropriately chosen coordinate system on the ambient space.

  31. Brian Clarke

    We prove that the L^2 Riemannian metric on the manifold of all smooth Riemannian metrics on a fixed closed, finite-dimensional manifold induces a metric space structure. As the L^2 metric is a weak Riemannian metric, this fact does not follow from general results. In addition, we prove several results on the exponential mapping and distance function of a wea

  32. Alessandra Silvestri, Mark Trodden

    Theoretical approaches to explaining the observed acceleration of the universe are reviewed. We briefly discuss the evidence for cosmic acceleration, and the implications for standard General Relativity coupled to conventional sources of energy-momentum. We then address three broad methods of addressing an accelerating universe: the introduction of a cosmolo

  33. J. Messud, M. Bender, E. Suraud

    We demonstrate how the separation of the total energy of a self-bound system into a functional of the internal one-body Fermionic density and a function of an arbitrary wave vector describing the center-of-mass kinetic energy can be used to set-up an &#34;internal&#34; Kohn-Sham scheme.

  34. Nedra Belhadjrhouma, Ali BenAmor

    We revisit Hardy&#39;s inequality in the scope of regular Dirichlet forms following an analytical method. We shall give an alternative necessary and sufficient condition for the occurrence of Hardy&#39;s inequality. A special emphasis will be given for the case where the Dirichlet form under consideration is strongly local, extending therefore some known res

  35. Martin Weimann

    We prove a theorem on algebraic osculation and we apply our result to the Computer Algebra problem of polynomial factorization. We consider X a smooth completion of the complex plane and D an effective divisor supported on the boundary of X. Our main result gives explicit conditions equivalent to that a given Cartier divisor on D extends to X. These osculati

  36. Kevin Dusling, Ismail Zahed

    We investigate the energy loss of heavy quarks in the gas, liquid and solid phase of a classical quark-gluon plasma (cQGP) using molecular dynamics simulations. The model consists of massive quarks and gluons interacting as a classical non-relativistic colored Coulomb gas. We show that the electric force decorrelates on a short time scale causing the energy

  37. Paul Koerber

    We scan for massive type IIA SU(3)-structure compactifications of the type AdS4 x CP3 with internal symmetry group SO(4). This group acts on CP3 with cohomogeneity one, so that one would expect new non-homogeneous solutions. We find however that all such solutions enhance their symmetry group to Sp(2) and form, in fact, the homogeneous family first described

  38. A. V. Tikhonov, S. Gottloeber, G. Yepes, Y. Hoffman

    Using high-resolution simulations within the Cold and Warm Dark Matter models we study the evolution of small scale structure in the Local Volume, a sphere of 8 Mpc radius around the Local Group. We compare the observed spectrum of mini-voids in the Local Volume with the spectrum of mini-voids determined from the simulations. We show that the \LWDM model can

  39. Ming Xiong, Huinan Zheng, Shui Wang

    The numerical studies of the interplanetary coupling between multiple magnetic clouds (MCs) are continued by a 2.5-dimensional ideal magnetohydrodynamic (MHD) model in the heliospheric meridional plane. The interplanetary direct collision (DC) / oblique collision (OC) between both MCs results from their same/different initial propagation orientations. Here t

  40. François Impens

    A hidden symmetry of the nonlinear wave equation is exploited to analyse the propagation of paraxial and uniform atom-laser beams in time-independent, quadratic and cylindrical potentials varying smoothly along the propagation axis. The quality factor and the paraxial ABCD formalism are generalized to account exactly for mean-field interaction effects in suc

  41. Alexandre Aubry, Arnaud Derode

    The distribution of singular values of the propagation operator in a random medium is investigated, in a backscattering configuration. Experiments are carried out with pulsed ultrasonic waves around 3 MHz, using an array of 64 programmable transducers placed in front of a random scattering medium. The impulse responses between each pair of transducers are me

  42. Xiang Liu

    Assuming that Y(4140) is the second radial excitation of the P-wave charmonium $χ_{cJ}^{\prime\prime}$ ($J=0, 1$), the hidden charm decay mode of Y(4140) is calculated in terms of the rescattering mechanism. Our numerical results show that the upper limit of the branching ratio of the hidden charm decay $Y(4140)\to J/ψϕ$ is on the order of $10^{-4}\sim 10^{-

  43. Per Austrin, Elchanan Mossel

    We study correlation bounds under pairwise independent distributions for functions with no large Fourier coefficients. Functions in which all Fourier coefficients are bounded by $δ$ are called $δ$-{\em uniform}. The search for such bounds is motivated by their potential applicability to hardness of approximation, derandomization, and additive combinatorics.

  44. Manoussos G. Grillakis, Matei Machedon, Dionisios Margetis

    Inspired by the works of Rodnianski and Schlein and Wu, we derive a new nonlinear Schrödinger equation that describes a second-order correction to the usual tensor product (mean-field) approximation for the Hamiltonian evolution of a many-particle system in Bose-Einstein condensation. We show that our new equation, if it has solutions with appropriate smooth

  45. R. Grein, M. Eschrig, G. Metalidis, Gerd Schön

    We study heterostructures of singlet superconductors (SC) and strongly spin-polarized ferromagnets (sFM) and show that a relative phase arises between the superconducting proximity amplitudes in the two ferromagnetic spin bands. We find a tunable pure spin supercurrent in a sFM contacted with only one SC electrode. We show that Josephson junctions are most e

  46. Stefano Finazzi, Stefano Liberati, Carlos Barceló

    Warp drives are very interesting configurations in General Relativity: At least theoretically, they provide a way to travel at superluminal speeds, albeit at the cost of requiring exotic matter to exist as solutions of Einstein&#39;s equations. However, even if one succeeded in providing the necessary exotic matter to build them, it would still be necessary

  47. Csaba Balázs, Dilani Kahawala

    In this work the LHC inverse problem is quantified in the Bayesian context by clarifying the relation between the mapping from the theory parameter space to experimental signature space and the inverse map. We demonstrate that, after complementing the LHC data by existing astrophysical, collider, and low energy measurements, a simple likelihood analysis is a

  48. Petr Benes

    We present a model-independent method of dealing with fermion flavor mixing in the case when instead of constant, momentum-independent mass matrices one has rather momentum-dependent self-energies. This situation is typical for strongly coupled models of dynamical fermion mass generation. We demonstrate our approach on the example of quark mixing. We show th

  49. Sarira Sahu, Nissim Fraija, Yong-Yeon Keum

    Neutrinos of energy about 5-20 MeV are produced due to the stellar collapse or merger events that trigger the Gamma-Ray Burst. Also low energy MeV neutrinos are produced within the fireball due to electron positron annihilation and nucleonic bremsstrahlung. Many of these neutrinos will propagate through the dense and relativistic magnetized plasma of the fir

  50. R. L. Doretto, Matthias Vojta

    In magnets with strong quantum fluctuations, paramagnetic ground states with or without confinement of spinon excitations can be realized. Here we discuss the physics of the confined phase in the vicinity of a confinement--deconfinement transition: This regime, likely relevant to a multitude of frustrated spin systems, is characterized by multiple length sca

  51. D. N. Makovetskii

    New critical surfaces have been analytically found for a 3D vectorial model of bistable pumping system of an optical-wavelength acoustic laser (phaser). The Lyapunov instability is possible for this pumping system at the upper branch for a high quality factor Qc of a pump resonator: Qc/Qm >> 1, where Qm is the magnetic quality factor. This instability is of

  52. Martin Lemoine, Jerome Martin, Jun'ichi Yokoyama

    We set constraints on moduli cosmology from the production of dark matter -- radiation and baryon -- radiation isocurvature fluctuations through modulus decay, assuming the modulus remains light during inflation. We find that the moduli problem becomes worse at the perturbative level as a significant part of the parameter space m_\sigma (modulus mass) -- \si

  53. S. Boogert, A. F. Hartin, M. Hildreth, D. Käfer

    Any future high energy e+e- linear collider aims at precision measurements of Standard Model quantities as well as of new, not yet discovered phenomena. In order to pursue this physics programme, excellent detectors at the interaction region have to be complemented by beam diagnostics of unprecedented precision. This article gives an overview of current plan

  54. Tim Roemer, Kirsten Schmitz

    We show that in the constant coefficient case the generic tropical variety of a graded ideal exists. This can be seen as the analogon to the existence of the generic initial ideal in Groebner basis theory. We determine the generic tropical variety as a set in general and as a fan for principal ideals and linear ideals.

  55. C. Trundle, A. Pastorello, S. Benetti, R. Kotak

    An optical photometric and spectroscopic analysis of the slowly-evolving Type IIn SN2007rt is presented, covering a duration of 481 days after discovery. Its earliest spectrum, taken approximately 100 days after the explosion epoch, indicates the presence of a dense circumstellar medium, with which the supernova ejecta is interacting. This is supported by th

  56. Jacek Dziarmaga, Marek M. Rams

    We argue that in a second order quantum phase transition driven by an inhomogeneous quench density of quasiparticle excitations is suppressed when velocity at which a critical point propagates across a system falls below a threshold velocity equal to the Kibble-Zurek correlation length times the energy gap at freeze-out divided by $\hbar$. This general predi

  57. Ivan Cheltsov, Constantin Shramov

    We study del Pezzo surfaces that are quasismooth and well-formed weighted hypersurfaces. In particular, we find all such surfaces whose alpha-invariant of Tian is greater than 2/3.

  58. Manoj Gopalakrishnan, Bindu S. Govindan

    The mitotic spindle is an important intermediate structure in eukaryotic cell division, in which each of a pair of duplicated chromosomes is attached through microtubules to centrosomal bodies located close to the two poles of the dividing cell. Several mechanisms are at work towards the formation of the spindle, one of which is the `capture&#39; of chromoso

  59. Andreas Arvanitoyeorgos, Kunihiko Mori, Yusuke Sakane

    The study of left-invariant Einstein metrics on compact Lie groups which are naturally reductive was initiated by J. E. D&#39;Atri and W. Ziller in 1979. In 1996 the second author obtained non-naturally reductive Einstein metrics on the Lie group SU(n) for $n \ge 6$, by using a method of Riemannian submersions. In the present work we prove existence of non-n

  60. L. Udby, N. H. Andersen, F. C. Chou, N. B. Christensen

    We present results of magnetic neutron diffraction experiments on the co-doped super-oxygenated La(2-x)Sr(x)CuO(4+y) (LSCO+O) system with x=0.09. The spin-density wave has been studied and we find long-range incommensurate antiferromagnetic order below T_N coinciding with the superconducting ordering temperature T_c=40 K. The incommensurability value is cons

  61. Yumiko Hironaka

    We give a general expression of spherical functions on $p$-adic homogeneous spaces of $G$, based on data of $G$ and functional equations of spherical functions. Then, we show a unified method to obtain functional equations of spherical functions and relate them those of $p$-adic local zeta functions of small prehomogeneous vector spaces.

  62. E. Schisano, E. Covino, J. M. Alcala&#39;, M. Esposito

    We characterize the physical properties of T Chamaeleontis, a transitional T Tauri star showing UX Ori-type variability, and of its associated disc, and probe possible effects of disc clearing processes. Different spectral diagnostics are examined, based on a rich collection of optical high- and low-resolution spectra. We determine radial and projected rotat

  63. Prado Martin-Moruno, Pedro F. Gonzalez-Diaz

    This paper deals with some thermodynamical aspects of Lorentzian wormholes, including the formulation of the three main laws and the consideration of a possible thermal emission made up of some sort of phantom radiation coming out from the wormhole at a negative temperature. In order for these topics to be consistently developed we have used a 2+2 formalism

  64. Mateusz Krzyzosiak, Zheyu Huang, Shiping Feng, Ryszard Gonczarek

    Within the framework of the kinetic energy driven superconductivity, the electromagnetic response in cuprate superconductors is studied in the linear response approach. The kernel of the response function is evaluated and employed to calculate the local magnetic field profile, the magnetic field penetration depth, and the superfluid density, based on the spe

  65. Chunfang Sun, Gangcheng Wang, Kang Xue

    A M-matrix which satisfies the Hecke algebraic relations is presented. Via the Yang-Baxterization approach, we obtain a unitary solution $\breve{R}(\theta,\varphi_{1},\varphi_{2})$ of Yang-Baxter Equation. It is shown that any pure two-qutrit entangled states can be generated via the universal $\breve{R}$-matrix assisted by local unitary transformations. A H

  66. Chunfang Sun, Gangcheng Wang, Taotao Hu, Chengcheng Zhou

    A method of constructing Temperley-Lieb algebras(TLA) representations has been introduced in [Xue \emph{et.al} arXiv:0903.3711]. Using this method, we can obtain another series of $n^{2}\times n^{2}$ matrices $U$ which satisfy the TLA with the single loop $d=\sqrt{n}$. Specifically, we present a $9\times9$ matrix $U$ with $d=\sqrt{3}$. Via Yang-Baxterization

  67. Durmus A. Demir, N. K. Pak

    The gravitational Higgs mechanism proposed by &#39;t Hooft in arXiv:0708.3184 involves the spacetime metric g_{mu nu} as well as the induced metric \bar{g}_{mu nu} proportional to η_{a b} \partial_{mu} ϕ^a \partial_{nu} ϕ^b where ϕ^{a} (a=0,...,3), as we call it, break all four diffeomorphisms spontaneously via the vacuum expectation values < ϕ^a > proportio

  68. Shiva Shankar

    This paper is withdrawn because of an error in Lemma 3.1

  69. G. A. Kohring

    Two large, open source software systems are analyzed from the vantage point of complex adaptive systems theory. For both systems, the full dependency graphs are constructed and their properties are shown to be consistent with the assumption of stochastic growth. In particular, the afferent links are distributed according to Zipf's law for both systems. Using

  70. Nguyen Dinh Dang

    The errors in the arguments, numerical results, and conclusions in the paper &#34;Test of a modified BCS theory performance in the picket fence model&#34; [Nucl. Phys. A 822 (2009) 1] by V.Yu. Ponomarev and A.I. Vdovin are pointed out. Its repetitions of already published material are also discussed.

  71. Elemer E Rosinger, Gusti van Zyl

    There has for longer been an interest in finding equivalent conditions which define inner product spaces, and the respective literature is considerable, see for instance Amir, which lists 350 such results. Here, in this tradition, an alternative definition of orthogonality is presented which does not make use of any inner product. This definition, in the spi

  72. Hiroyuki Nakaoka

    In the efforts to define a 2-categorical analog of an abelian category, two (or three) notions of &#34;abelian 2-categories&#34; are defined. One is the relatively exact 2-category, and the other(s) is the (2-)abelian Gpd-category. We compare these notions. Since they proceed independently in their own way, in different settings and terminologies, it will be

  73. Wei Liao

    We derive a series of moment equations describing the motion and flavor transformation of neutrinos in supernova. We find a particular series of moments of neutrino density matrix in supernova. The emission angle distribution of neutrinos is described by this series of moments. We expand the equation of neutrinos using these moments and obtain moment equatio

  74. Anis Biswas, Tapas Samanta, S. Banerjee, I. Das

    Recently the inverse magnetocaloric effect is observed for different compounds. However there is very rare for any manifestation of the effect to be seen in manganites. We have found inverse magnetocaloric effect in the case of polycrystalline La$_{0.125}$Ca$_{0.875}$MnO$_{3}$. Such phenomenon is attributed to the stabilization of antiferromagnetic state ass

  75. Danko Ilik, Gyesik Lee, Hugo Herbelin

    We introduce a notion of Kripke model for classical logic for which we constructively prove soundness and cut-free completeness. We discuss the novelty of the notion and its potential applications.

  76. Elise Janvresse, Steve Kalikow, Thierry De La Rue

    We introduce a two-player game, in which each player extends a given sequence by picking a free element in a domain D of the real line. The aim of the players is to control the parity of the number of transpositions necessary to put the final sequence in order. We will see that the winner can be the last player, the second last player, the first player, the

  77. Anatoli Iouditski, Fatma Kilinc Karzan, Arkadii S. Nemirovski

    We propose necessary and sufficient conditions for a sensing matrix to be &#34;s-semigood&#34; -- to allow for exact $\ell_1$-recovery of sparse signals with at most $s$ nonzero entries under sign restrictions on part of the entries. We express the error bounds for imperfect $\ell_1$-recovery in terms of the characteristics underlying these conditions. Furth

  78. Hongsheng Zhang, Hyerim Noh

    A new braneworld in the sourced-Taub background is proposed. The gravity field equations in the internal source region and external vacuum region are investigated, respectively. We find that the equation of state for the effective dark energy of a dust brane in the source region can cross the phantom divide $w=-1$. Furthermore, there is a drop on $H(z)$ diag

  79. Hongsheng Zhang, Hyerim Noh

    A new class of plane symmetric solution sourced by a perfect fluid is found in our recent work. An n-dimensional ($n\geq 4$) global plane symmetric solution of Einstein field equation generated by a perfect fluid source is investigated, which is the direct generalization of our previous 4-dimensional solution. One time-like Killing vector and $(n-2)(n-1)/2$

  80. Hongsheng Zhang, Hyerim Noh

    A new class of static plane symmetric solution of Einstein field equation, which is judged as the source of Taub solution, was presented in our previous work. In this letter the properties of geodesics of this solution are explored. It is found that this solution can be an appropriate simulation to the field of a uniformly accelerated observer in Newton mech

  81. Xi-Han Li, Bao-Kui Zhao, Yu-Bo Sheng, Fu-Guo Deng

    We present two robust quantum key distribution protocols against two kinds of collective noise, following some ideas in quantum dense coding. Three-qubit entangled states are used as quantum information carriers, two of which forming the logical qubit which is invariant with a special type of collective noise. The information is encoded on logical qubits wit

  82. Lilia Anguelova, Vincenzo Calo, Michele Cicoli

    We present a detailed study of the finite-temperature behaviour of the LARGE Volume type IIB flux compactifications. We show that certain moduli can thermalise at high temperatures. Despite that, their contribution to the finite-temperature effective potential is always negligible and the latter has a runaway behaviour. We compute the maximal temperature $T_

  83. Robert Seiringer, Daniel Ueltschi

    We prove exponential decay of the off-diagonal correlation function in the two-dimensional homogeneous Bose gas when a^2 ρis small and the temperature T satisfies T > 4 πρ/ \ln |\ln(a^2ρ). Here, a is the scattering length of the repulsive interaction potential and ρis the density. To leading order in a^2 ρ, this bound agrees with the expected critical temper

  84. Carlos Navarrete-Benlloch, Alejandro Romanelli, Eugenio Roldán, Germán J. de Valcárcel

    In this article we explore the quantum properties of a degenerate optical parametric oscillator when it is tuned to the first family of transverse modes at the down converted frequency.

  85. Chao-Jun Feng, Xin Zhang

    In the holographic Ricci dark energy (RDE) model, the parameter $α$ plays an important role in determining the evolutionary behavior of the dark energy. When $α<1/2$, the RDE will exhibit a quintom feature, i.e., the equation of state of dark energy will evolve across the cosmological constant boundary $w=-1$. Observations show that the parameter $α$ is inde

  86. Toby Gee, David Savitt

    We study the possible weights of an irreducible 2-dimensional modular mod p representation of the absolute Galois group of F, where F is a totally real field which is totally ramified at p, and the representation is tamely ramified at the prime above p. In most cases we determine the precise list of possible weights; in the remaining cases we determine the p

  87. Ivan Dimitrov, Vyacheslav Futorny, Dimitar Grantcharov

    We compare two combinatorial definitions of parabolic sets of roots. We show that these definitions are equivalent for simple finite dimensional Lie algebras, affine Lie algebras, and toroidal Lie algebras. In contrast, these definitions are not always equivalent for simple finite dimensional Lie superalgebras.

  88. Zotin K. -H. Chu

    We revisit the persistent flow of a superfluid in a thin wavy-rough annulus. The existence of a phase memory around this thin corrugated annulus is shown to be responsible for the energy minima with a periodic dependence on the total momentum which is directly related to the quantization of circulation. We also illustrate the general features using the ideal

  89. Viveck R. Cadambe, Syed A. Jafar, Chenwei Wang

    It has been conjectured by Host-Madsen and Nosratinia that complex Gaussian interference channels with constant channel coefficients have only one degree-of-freedom regardless of the number of users. While several examples are known of constant channels that achieve more than 1 degree of freedom, these special cases only span a subset of measure zero. In oth

  90. Justin Sawon

    Four-folds with trivial canonical bundles are divided into six classes according to their holonomy group. We consider examples that are fibred by abelian surfaces over the projective plane. We construct such fibrations in five of the six classes, and prove that there is no such fibration in the sixth class. We classify all such fibrations whose generic fibre

  91. J. Suffczynski, A. Dousse, K. Gauthron, A. Lemaitre

    The origin of the emission within the optical mode of a coupled quantum dot-micropillar system is investigated. Time-resolved photoluminescence is performed on a large number of deterministically coupled devices in a wide range of temperature and detuning. The emission within the cavity mode is found to exhibit the same dynamics as the spectrally closest qua

  92. L. C. Johnson, R. H. Mendez, A. M. Teodorescu

    Using an [OIII]5007 on-band/off-band filter technique, we identify 109 planetary nebulae (PNe) candidates in M 82, using the FOCAS instrument at the 8.2m Subaru Telescope. The use of ancillary high-resolution HST ACS H-alpha imaging aided in discriminating PNe from contaminants such as supernova remnants and compact HII regions. Once identified, these PNe re

  93. H. Leblond, R. Barille, S. Ahamadi-kandjani, J. -M. Nunzi

    A model based on Fick's law of diffusion as a phenomenological description of the molecular motion, and on the coupled mode theory, is developped to describe single-beam surface relief grating formation in azopolymers thin films. It allows to explain the mechanism of spontaneous patterning, and self-organization. It allows also to compute the surface relief

  94. V. V. Dobrovitski, A. E. Feiguin, R. Hanson, D. D. Awschalom

    We investigate the Rabi oscillations decay of a spin decohered by a spin bath whose internal dynamics is caused by dipolar coupling between the bath spins. The decay form and rate as a function of the intra-bath coupling is studied analytically, and confirmed numerically. The decay in general has neither exponential/Gaussian or power-law form, and changes no

  95. E. S. Rykoff, F. Aharonian, C. W. Akerlof, M. C. B. Ashley

    We report on a complete set of early optical afterglows of gamma-ray bursts (GRBs) obtained with the ROTSE-III telescope network from March 2005 through June 2007. This set is comprised of 12 afterglows with early optical and Swift/XRT observations, with a median ROTSE-III response time of 45 s after the start of gamma-ray emission (8 s after the GCN notice

  96. Alberto De Gregorio, Fabio Sebastiani

    We outline Fermi&#39;s early attitude towards old quantum physics. We sketch out the context from which his interest for quantum physics arose, and we deal with his work on quantum statistics. We also go through the first two courses on theoretical physics he held in Rome, and his 1928 book on atomic physics.

  97. Felipe B. Rizzato, Renato Pakter, Yan Levin

    A statistical theory is presented which allows to calculate the stationary state achieved by a driven system after a process of collisionless relaxation. The theory is applied to study an electron beam driven by an external electric field. The Vlasov equation with appropriate boundary conditions is solved analytically and compared with the molecular dynamics

  98. C. F. Miclea, A. C. Mota, M. Nicklas, R. Cardoso

    We report on the vortex dynamics of a single crystal of the non-centrosymmetric heavy-fermion superconductor CePt$_{3}$Si. Decays of the remnant magnetization display a clean logarithmic time dependence with rates that follow the temperature dependence expected from the Kim-Anderson theory. The creep rates are lower than observed in any other centrosymmetric

  99. Federico Marulli, Silvia Bonoli, Enzo Branchini, Roberto Gilli

    We study the spatial distribution of X-ray selected AGN in the framework of hierarchical co-evolution of supermassive black holes and their host galaxies and dark matter haloes. To this end, we have applied the model developed by Croton et al.(2006), De Lucia & Blaizot(2007) and Marulli et al.(2008) to the output of the Millennium Run and obtained hundreds o

  100. C. Wang, G. Theocharis, P. G. Kevrekidis, N. Whitaker

    We study the existence and stability of localized states in the two-dimensional (2D) nonlinear Schrodinger (NLS)/Gross-Pitaevskii equation with a symmetric four-well potential. Using a fourmode approximation, we are able to trace the parametric evolution of the trapped stationary modes, starting from the corresponding linear limits, and thus derive the compl