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December 2010 arXiv papers — page 30

Showing 2,9013,000 of 6,281 papers

  1. Amjad Ashoorioon, Gary Shiu

    We identify a two-parameter family of excited states within slow-roll inflation for which either the corrections to the two-point function or the characteristic signatures of excited states in the three-point function -- i.e. the enhancement for the flattened momenta configurations-- are absent. These excited states may nonetheless violate the adiabaticity c

  2. MINOS Collaboration

    The magnetized MINOS Near Detector, at a depth of 225 meters of water equivalent (mwe), is used to measure the atmospheric muon charge ratio. The ratio of observed positive to negative atmospheric muon rates, using 301 days of data, is measured to be 1.266+/-0.001(stat.)+0.015/-0.014(syst.). This measurement is consistent with previous results from other sha

  3. Francesc Fité

    Given a pair of abelian varieties defined over a number field k and isogenous over a finite Galois extension L/k, we define a rational Artin representation of the group Gal(L/k) that shows a global relation between the L-functions of each variety and provides certain information about their decomposition up to isogeny over L. We study several properties of t

  4. J. A. Nieto

    We show that the equations of motion associated with a complexified sigma-model action do not admit manifest dual SO(n,n) symmetry. In the process we discover new type of numbers which we called `complexoids' in order to emphasize their close relation with both complex numbers and matroids. It turns out that the complexoids allow to consider the analogue

  5. Erik Aurell, Hamed Mahmoudi

    We study stationary states in a diluted asymmetric (kinetic) Ising model. We apply the recently introduced dynamic cavity method to compute magnetizations of these stationary states. Depending on the update rule, different versions of the dynamic cavity method apply. We here study synchronous updates and random sequential updates, and compare local propertie

  6. Thomas Engl, Jack Kuipers, Klaus Richter

    When coupling a superconductor to a normal conducting region the physical properties of the system are highly affected by the superconductor. We will investigate the effect of one or two superconductors on the conductance of a ballistic chaotic quantum dot to leading order in the total channel number using trajectory based semiclassics. The results show that

  7. James T. Liu, Wafic Sabra, Zhichen Zhao

    In AdS/CFT, the holographic Weyl anomaly computation relates the a-anomaly coefficient to the properties of the bulk action at the UV fixed point. This universal behavior suggests the possibility of a holographic c-theorem for the a-anomaly under flows to the IR. We prove such a c-theorem for higher curvature Lovelock gravity, where the bulk equations of mot

  8. K. Hebeler, S. K. Bogner, R. J. Furnstahl, A. Nogga

    We present new nuclear matter calculations based on low-momentum interactions derived from chiral effective field theory potentials. The current calculations use an improved treatment of the three-nucleon force contribution that includes a corrected combinatorial factor beyond Hartree-Fock that was omitted in previous nuclear matter calculations. We find rea

  9. Michael McCollough, Karri Koljonen, Diana Hannikainen, Guy Pooley

    Cygnus X-3 is a unique microquasar which shows X-ray state changes, strong radio emission, and relativistic jets. It is also an unusual X-ray binary with the mass-donating companion being a high mass star Wolf-Rayet but the orbital modulation (as inferred from X-ray emission) is only 4.8 hours, a value more common in low-mass systems. It has recently been sh

  10. Nan Su

    The weak-coupling expansion of the QCD free energy is known to order g_s^6log{g_s}, however, the resulting series is poorly convergent at phenomenologically relevant temperatures. In this proceedings, I discuss hard-thermal-loop perturbation theory (HTLpt) which is a gauge-invariant reorganization of the perturbative expansion for gauge theories. I review a

  11. Stéphane Jean Eric Lengrand, Roy Dyckhoff, James McKinna

    Basic proof-search tactics in logic and type theory can be seen as the root-first applications of rules in an appropriate sequent calculus, preferably without the redundancies generated by permutation of rules. This paper addresses the issues of defining such sequent calculi for Pure Type Systems (PTS, which were originally presented in natural deduction sty

  12. Przemyslaw Koscik

    We study a two-dimensional system of two Coulombically interacting electrons in an external harmonic confining potential. More precisely, we present calculations for the singlet ground-state of the system. We explain the nature of the degeneracy in the spectrum of the reduced density matrix and provide detailed results for the dependencies of the entanglemen

  13. Niek Bouman, Sem Borst, Johan van Leeuwaarden

    We examine the stability of wireless networks whose users are distributed over a compact space. A subset of users is called {\it admissible} when their simultaneous activity obeys the prevailing interference constraints and, in each time slot, an admissible subset of users is selected uniformly at random to transmit one packet. We show that, under a mild con

  14. Yoritaka Iwata, Joachim A. Maruhn

    The tensor and spin-orbit forces contribute essentially to the formation of the spin mean field, and give rise to the same dynamical effect, namely spin polarization. In this paper, based on time-dependent density functional calculations, we show that the tensor force, which usually acts like a small correction to the spin-orbit force, becomes more important

  15. Robert V. Harlander, Franziska Hofmann, Hendrik Mantler

    The cross section through gluon fusion is calculated for the production of the light neutral Higgs boson through next-to-leading order QCD within the Minimal Supersymmetric Standard Model. The quark-mediated contributions are taken into account exactly, while for the genuinely supersymmetric terms we use expressions obtained in the limit of large squark, glu

  16. Pratik Shah, Samaresh Chatterji

    In this article we extend the computational geometric curve reconstruction approach to curves in Riemannian manifolds. We prove that the minimal spanning tree, given a sufficiently dense sample, correctly reconstructs the smooth arcs and further closed and simple curves in Riemannian manifolds. The proof is based on the behaviour of the curve segment inside

  17. C. Quesne

    In memory of Marcos Moshinsky, who promoted the algebraic study of the harmonic oscillator, some results recently obtained on an infinite family of deformations of such a system are reviewed. This set, which was introduced by Tremblay, Turbiner, and Winternitz, consists in some Hamiltonians $H_k$ on the plane, depending on a positive real parameter $k$. Two

  18. R. Friedrich, M. Voßkuhle, O. Kamps, M. Wilczek

    We present a statistical analysis of the two-point vorticity probability density of the vorticity field generated in the inverse cascade of stationary two-dimensional turbulence.

  19. William Nelson

    The cosmology of general fourth order corrections to Einstein gravity is considered, both for a homogeneous and isotropic background and for general tensor perturbations. It is explicitly shown how the standard cosmological history can be (approximately) reproduced and under what condition the evolution of the tensor modes remain (approximately) unchanged. R

  20. Stefan Groot Nibbelink

    In this work we attempt to bridge the gap between heterotic orbifold models and Calabi-Yau compactifications using gauged linear sigma models (GLSMs) with (2,0) worldsheet supersymmetry. We associate a specific GLSM to a heterotic orbifold model with twisted states that have non-vanishing vacuum expectation values (VEVs): The charges of the GLSM superfields

  21. Christian Wegner

    We prove the K-theoretic Farrell-Jones conjecture with (twisted) coefficients for CAT(0)-groups.

  22. Mikael Fernandus Simalango, Sangyoon Oh

    Advances in web technologies have driven massive content uploads and requests that can be identified by the increased usage of multimedia web and social web services. This situation enforces the content providers to scale their infrastructure in order to cope with the extra provisioning of network traffic, storage and other resources. Since the complexity an

  23. Simon Schettler, Tillmann Boeckel, Jurgen Schaffner-Bielich

    The QCD phase diagram might exhibit a first order phase transition for large baryochemical potentials. We explore the cosmological implications of such a QCD phase transition in the early universe. We propose that the large baryon-asymmetry is diluted by a little inflation where the universe is trapped in a false vacuum state of QCD. The little inflation is

  24. J. M. Speight

    It is shown that the quantum ground state energy of particle of mass m and electric charge e moving on a compact Riemann surface under the influence of a constant magnetic field of strength B is E_0=eB/2m. Remarkably, this formula is completely independent of both the geometry and topology of the Riemann surface. The formula is obtained by reinterpreting the

  25. Zhi-Gang Wang

    In this article, we study the mass spectrum of the baryon-antibaryon bound states $p\bar{p}$, $Σ\barΣ$, $Ξ\barΞ$, $Λ\barΛ$, $p\bar{N}(1440)$, $Σ\barΣ(1660)$, $Ξ\barΞ^\prime$ and $Λ\barΛ(1600)$ with the Bethe-Salpeter equation. The numerical results indicate that the $p\bar{p}$, $Σ\barΣ$, $Ξ\barΞ$, $p\bar{N}(1440)$, $Σ\barΣ(1660)$, $Ξ\barΞ^\prime$ bound state

  26. Itai Arad

    This is not a disproof of the quantum PCP conjecture! In this note we use perturbation on the commuting Hamiltonian problem on a graph, based on results by Bravyi and Vyalyi, to provide a partial no-go theorem for quantum PCP. Specifically, we derive an upper bound on how large the promise gap can be for the quantum PCP still to hold, as a function of the no

  27. Ahmet Seven

    In this paper, we determine representatives for the mutation classes of skew-symmetrizable 3x3 matrices and associated graphs using a natural minimality condition, generalizing and strengthening results of Beineke-Brustle-Hille and Felikson-Shapiro-Tumarkin. Furthermore, we obtain a new numerical invariant for the mutation operation on skew-symmetrizable mat

  28. Christian Konrad, Frederic Magniez

    We study the problem of validating XML documents of size $N$ against general DTDs in the context of streaming algorithms. The starting point of this work is a well-known space lower bound. There are XML documents and DTDs for which $p$-pass streaming algorithms require $Ω(N/p)$ space. We show that when allowing access to external memory, there is a determini

  29. S. a Beccara, G. Garberoglio, P. Faccioli

    We study the role of quantum fluctuations of atomic nuclei in the real-time dynamics of non-equilibrium macro-molecular transitions. To this goal we introduce an extension of the Dominant Reaction Pathways (DRP) formalism, in which the quantum corrections to the classical overdamped Langevin dynamics are rigorously taken into account to order h^2 . We first

  30. Javier J. Gutiérrez, Oliver Röndigs, Markus Spitzweck, Paul Arne Østvær

    Colored operads were introduced in the 1970's for the purpose of studying homotopy invariant algebraic structures on topological spaces. In this paper we introduce colored operads in motivic stable homotopy theory. Our main motivation is to uncover hitherto unknown highly structured properties of the slice filtration. The latter decomposes every motivic

  31. Stephanie Keller-Schmidt, Murat Tugrul, Victor M. Eguiluz, Emilio Hernandez-Garcia

    We introduce a one-parametric family of tree growth models, in which branching probabilities decrease with branch age $τ$ as $τ^{-α}$. Depending on the exponent $α$, the scaling of tree depth with tree size $n$ displays a transition between the logarithmic scaling of random trees and an algebraic growth. At the transition ($α=1$) tree depth grows as $(\log n

  32. V. I. Man'ko, G. Marmo, A. Porzio, S. Solimeno

    We experimentally verify uncertainty relations for mixed states in the tomographic representation by measuring the radiation field tomograms, i.e. homodyne distributions. Thermal states of single-mode radiation field are discussed in details as paradigm of mixed quantum state. By considering the connection between generalised uncertainty relations and optica

  33. Chanyong Park, Bum-Hoon Lee

    After considering a solitonic string moving in the Poincare $AdS$ and two-dimensional sphere, we calculate the two-point correlation function of magnon and spike in the semi-classical limit without any explicit solution. We also calculate the three-point correlation functions between two heavy and one light operators. We find that the coupling between two he

  34. G. Gazzola, H. G. Fargnoli, A. P. Baêta Scarpelli, Marcos Sampaio

    We consider an effective model formed by usual QED (minimal coupling) with the addition of a nonminimal Lorentz violating interaction (proportional to a fixed 4-vector $b_μ$) which may radiatively generate both CPT even and odd terms in the pure gauge sector. We show that gauge invariance from usual QED, considered as a limit of the model for $b_μ\rightarrow

  35. Richard G. Morris, Alan J. McKane

    We investigate the stability of growing vesicles using the formalism of nonequilibrium thermodynamics. The vesicles are growing due to the accretion of lipids to the bilayer which forms the vesicle membrane. The thermodynamic description is based on the hydrodynamics of a water{/}lipid mixture together with a model of the vesicle as a discontinuous system in

  36. Heidi Kuismanen, Juho Pelto, Iiro Vilja

    We study a modified version of a $U(1)_{B-L}$ gauged MSSM that was recently shown to produce a new source of leptogenesis through the CP asymmetry of sneutrinos and antisneutrinos (K.S. Babu, Y. Meng, Z. Tavartkiladze, Phys Lett B681:37 (2009)). By taking all superpotential terms and couplings between the MSSM Higgs and $B-L$ scalar sectors into account we f

  37. Matthias Rybarsch, Stefan Bornholdt

    Spin models of neural networks and genetic networks are considered elegant as they are accessible to statistical mechanics tools for spin glasses and magnetic systems. However, the conventional choice of variables in spin systems may cause problems in some models when parameter choices are unrealistic from a biological perspective. Obviously, this may limit

  38. P. Chamorro-Posada, P. Martín-Ramos, J. Sánchez-Curto, J. C. Garcia-Escartin

    We study nonlinear wave phenomena in coupled ring resonator optical waveguides in the tight coupling regime. A discrete model for the system dynamics is put forward and its steady state nonlinear Bloch modes are derived. The switching behavior of the transmission system is addressed numerically and the results are explained in the light of this analytical re

  39. Betti Hartmann, Claus Lämmerzahl, Parinya Sirimachan

    (p,q)-strings are bound states of p F-strings and q D-strings and are predicted to form at the end of brane inflation. As such these cosmic superstrings should be detectable in the universe. In this paper we argue that they can be detected by the way that massive and massless test particles move in the space-time of these cosmic superstrings, in particular w

  40. Guro K. Svendsen, Helge Weman, Johannes Skaar

    Nanowires show a large potential for various electrooptical devices, such as light emitting diodes, solar cells and nanowire lasers. We present a direct method developed to calculate the modal reflection and transmission matrix at the end facets of a waveguide of arbitrary cross section, resulting in a generalized version of the Fresnel equations. The reflec

  41. Yann Jullian

    We give an algorithm for finding the index of a positive outer automorphism of the free group, and prove the algorithm exits in a finite time.

  42. Takuma Aihara

    The notion of silting mutation was introduced by Iyama and the author. In this paper we mainly study silting mutation for self-injective algebras and prove that any representation-finite symmetric algebra is tilting-connected. Moreover we give some sufficient conditions for a Bongartz-type Lemma to hold for silting objects.

  43. Minoru Eto, Koji Hashimoto, Hideaki Iida, Akitsugu Miwa

    We apply a generic framework of linear sigma models for revealing a mechanism of the mysterious phenomenon, the chiral magnetic effect, in quark-gluon plasma. An electric current arises along a background magnetic field, which is given rise to by Q-balls (non-topological solitons) of the linear sigma model with axial anomaly. We find additional alternating c

  44. M. Ciafaloni, S. Munier

    We present a full study of the 3-body problem in gravity in flat (2+1)-dimensional space-time, and in the nonrelativistic limit of small velocities. We provide an explicit form of the ADM Hamiltonian in a regular coordinate system and we set up all the ingredients for canonical quantization. We emphasize the role of a U(2) symmetry under which the Hamiltonia

  45. ALICE Collaboration

    The production of mesons containing strange quarks (K$^0_s$, $ϕ$) and both singly and doubly strange baryons ($Λ$, Anti-$Λ$, and $Ξ$+Anti-$Ξ$) are measured at central rapidity in pp collisions at $\sqrt{s}$ = 0.9 TeV with the ALICE experiment at the LHC. The results are obtained from the analysis of about 250 k minimum bias events recorded in 2009. Measureme

  46. Souvik Banerjee, Sayan K. Chakrabarti, Sudipta Mukherji, Binata Panda

    We argue that a convenient way to analyze instabilities of black holes in AdS space is via Bragg-Williams construction of a free energy function. Starting with a pedagogical review of this construction in condensed matter systems and also its implementation to Hawking-Page transition, we study instabilities associated with hairy black holes and also with the

  47. C. -C. Chen, C. J. Jia, A. F. Kemper, R. R. P. Singh

    Although the parent iron-based pnictides and chalcogenides are itinerant antiferromagnets, the use of local moment picture to understand their magnetic properties is still widespread. We study magnetic Raman scattering from a local moment perspective for various quantum spin models proposed for this new class of superconductors. These models vary greatly in

  48. V. P. Ruban

    Highly accurate direct numerical simulations have been performed for two-dimensional free-surface potential flows of an ideal incompressible fluid over a constant depth $h$, in the gravity field $g$. In each numerical experiment, at $t=0$ the free surface profile was in the form $y=A_0\cos(2πx/L)$, and the velocity field ${\bf v}=0$. The computations demonst

  49. Daniele Fargion, Daniele D'Armiento, Paolo Desiati, Paolo Paggi

    A MINOS result seemed to hint a different anti-neutrino mass splitting and mixing angle with respect to the neutrino ones, offering a hint for a CPT violation in lepton sector. However more recent MINOS data reduced the neutrino-antineutrino differences leading to a narrow discrepancy almost compatible with no CPT violation, hard to be disentangled. Moreover

  50. Nicholas Sheridan

    The n-dimensional pair of pants is defined to be the complement of n+2 generic hyperplanes in CP^n. We construct an immersed Lagrangian sphere in the pair of pants and compute its endomorphism A_{\infty} algebra in the Fukaya category. On the level of cohomology, it is an exterior algebra with n+2 generators. It is not formal, and we compute certain higher p

  51. Tatsuhiko N. Ikeda, Yu Watanabe, Masahito Ueda

    We derive an upper bound on the difference between the long-time average and the microcanonical ensemble average of observables in isolated quantum systems. We propose, numerically verify, and analytically support a new hypothesis, eigenstate randomization hypothesis (ERH), which implies that in the energy eigenbasis the diagonal elements of observables fluc

  52. Tim Siu-Tang Leung, Kazutoshi Yamazaki

    This paper studies the valuation of a class of default swaps with the embedded option to switch to a different premium and notional principal anytime prior to a credit event. These are early exercisable contracts that give the protection buyer or seller the right to step-up, step-down, or cancel the swap position. The pricing problem is formulated under a st

  53. Takayasu Sekihara, Tetsuo Hyodo, Daisuke Jido

    The internal structure of the resonant Lambda(1405) state is investigated based on meson-baryon coupled-channels chiral dynamics, by evaluating density distributions obtained from the form factors of the Lambda(1405) state. The form factors are defined as an extension of the ordinary stable particles and are directly evaluated from the meson-baryon scatterin

  54. Shiguang Ma

    In this paper I study the constant mean curvature surface in asymptotically flat 3-manifolds with general asymptotics. Under some weak condition, I prove that outside some compact set in the asymptotically flat 3-manifold with positive mass, the foliation of stable spheres of constant mean curvature is unique.

  55. Piotr Sułkowski

    We construct a free fermion and matrix model representation of refined BPS generating functions of D2 and D0 branes bound to a single D6 brane, in a class of toric manifolds without compact four-cycles. In appropriate limit we obtain a matrix model representation of refined topological string amplitudes. We consider a few explicit examples which include a ma

  56. Fuminobu Takahashi, Tsutomu T. Yanagida

    We argue that strong dynamics at the Planck scale can solve the cosmological moduli problem. We discuss its implications for inflation models, and find that a certain type of multi-field inflation model is required for this mechanism to work, since otherwise it would lead to the serious eta-problem. Combined with the inflaton-induced gravitino problem, we sh

  57. Mikhail Belyaev, Roman Rafikov

    Collisions resulting in fragmentation are important in shaping the mass spectrum of minor bodies in the asteroid belt, the Kuiper belt, and debris disks. Models of fragmentation cascades typically find that in steady-state, the solution for the particle mass distribution is a power law in the mass. However, previous studies have typically assumed that the ma

  58. Yong Zeng, Jinjie Liu, Douglas H. Werner

    Electrostatic properties of two-dimensional nanosystems can be described by their geometry resonances. In this paper we prove that these modes as well as the corresponding eigenvalues are invariant under any conformal transformation. This invariance further leads to a new way to studying the transformed structures. Namely, transforming a geometry is equivale

  59. A. Kashlinsky, F. Atrio-Barandela, H. Ebeling

    We present new results on the "dark flow" from a measurement of the dipole in the distribution of peculiar velocities of galaxy clusters, applying the methodology proposed and developed by us earlier. Our latest measurement is conducted using new, low-noise 7-yr WMAP data as well as an all-sky sample of X-ray selected galaxy clusters compiled exclusi

  60. Daniel L. Jafferis

    The three sphere partition function, Z, of three dimensional theories with four supercharges and an R-symmetry is computed using localization, resulting in a matrix integral over the Cartan of the gauge group. There is a family of couplings to the curved background, parameterized by a choice of R-charge, such that supersymmetry is preserved; Z is a function

  61. Andres Anabalon, Fabrizio Canfora, Alex Giacomini, Julio Oliva

    In this paper the zero modes of the de Donder gauge Faddeev-Popov operator for three dimensional gravity with negative cosmological constant are analyzed. It is found that the three dimensional AdS vacuum produces (infinitely many) normalizable, smooth zero modes of the Faddeev-Popov operator. On the other hand, it is found that the BTZ black hole (including

  62. Jin-cheng Wang, Vivian de la Incera, Efrain J. Ferrer, Qun Wang

    The effect of an applied magnetic field in the crossover from Bose-Einstein condensate (BEC) to Bardeen-Cooper-Schrieffer (BCS) pairing regimes is investigated. We use a model of relativistic fermions and bosons inspired by those previously used in the context of cold fermionic atoms and in the magnetic-color-flavor-locking phase of color superconductivity.

  63. Alejandro Aviles, Jorge L. Cervantes-Cota

    We present a scenario in which a scalar field dark energy is coupled to the trace of the energy momentum tensor of the baryonic matter fields. In the slow-roll regime, this interaction could give rise to the cosmological features of dark matter. We work out the cosmological background solutions and fit the parameters of the model using the Union 2 supernovae

  64. H. Bessaih, R. Kapica, T. Szarek

    We formulate and prove a new criterion for stability of e-processes. It says that any e-process which is averagely bounded and concentrating is asymptotically stable. In the second part, we show how this general result applies to some shell models (the Goy and the Sabra model). Indeed, we manage to prove that the processes corresponding to these models satis

  65. Hoon Huh, Antonia M. Tulino, Giuseppe Caire

    We consider the downlink of a multi-cell system with multi-antenna base stations and single-antenna user terminals, arbitrary base station cooperation clusters, distance-dependent propagation pathloss, and general "fairness" requirements. Base stations in the same cooperation cluster employ joint transmission with linear zero-forcing beamforming, sub

  66. G. Chiribella, A. Toigo, V. Umanità

    Quantum supermaps are higher-order maps transforming quantum operations into quantum operations. Here we extend the theory of quantum supermaps, originally formulated in the finite dimensional setting, to the case of higher-order maps transforming quantum operations with input in a separable von Neumann algebra and output in the algebra of the bounded operat

  67. Diogo R. Boito, Rafel Escribano, Matthias Jamin

    The $Kπ$ vector form factor, $F_+^{Kπ}$, used to reproduce the Belle spectrum of $\tauKpi$ decays is described by means of a three-times subtracted dispersion relation also incorporating constraints from $K_{l3}$ decays. The slope and curvature of $F_+^{Kπ}$ are fitted to the data yielding $λ_+'=(25.49 \pm 0.31) \times 10^{-3}$ and $λ_+"= (12.22 \pm

  68. Sidney van den Bergh

    The Magellanic Clouds may have joined our Milky Way system quite recently. The Large Magellanic Cloud turns out to be a remarkably luminous object that is close to the upper luminosity limit of the class of magellanic irregular galaxies.

  69. Muhammad Usman, Susannah Heck, Edmund Clarke, Peter Spencer

    The design of some optical devices such as semiconductor optical amplifiers for telecommunication applications requires polarization-insensitive optical emission at the long wavelengths (1300-1550 nm). Self-assembled InAs/GaAs quantum dots (QDs) typically exhibit ground state optical emission at wavelengths shorter than 1300 nm with highly polarization-sensi

  70. Yancy L. Shirley, Tracy L. Huard, Klaus M. Pontoppidan, David J. Wilner

    Infrared extinction maps and submillimeter dust continuum maps are powerful probes of the density structure in the envelope of star-forming cores. We make a direct comparison between infrared and submillimeter dust continuum observations of the low-mass Class 0 core, B335, to constrain the ratio of submillimeter to infrared opacity (\kaprat) and the submilli

  71. Radovan Dermisek

    We review motivation for a light charged Higgs scenario that occurs in a class of models with a light CP-odd Higgs boson. If the light CP-odd Higgs is doublet-like the charged Higgs is typically lighter than the top quark and it dominantly decays into $W^\pm A$ with $B(H^+ \to W^+ A) > 70%$. We summarize experimental constraints from direct searches and disc

  72. Charles B. Chiu, Rudolph C. Hwa

    A relationship between the ridge distribution in $Δη$ and the single-particle distribution in $η$ is proposed. It is then verified by use of the data from PHOBOS on both distributions. The implication seems to point to the possibility that there is no long-range longitudinal correlation. An interpretation of the phenomenological observation along that possib

  73. Bo Zhang, Zi-Gao Dai

    In this paper we present the spectrum of synchro-curvature self-Compton (SCSC) radiation of relativistic electrons with a power-law distribution of Lorentz factors. We find that the resulting spectrum is significantly different from that of either synchrotron self-Compton or curvature self-Compton radiation if both the curvature radius of the magnetic field

  74. Stefan Forcey, Aaron Lauve, Frank Sottile

    We develop the notion of the composition of two coalgebras, which arises naturally in higher category theory and in the theory of species. We prove that the composition of two cofree coalgebras is again cofree, and we give sufficient conditions that ensure the composition is a one-sided Hopf algebra. We show these conditions are satisfied when one coalgebra

  75. M. O'Dowd, N. F. Bate, R. L. Webster, R. Wayth

    The detailed workings of the central engines of powerful quasars remain a mystery. This is primarily due to the fact that, at their cosmological distances, the inner regions of these quasars are spatially unresolvable. Reverberation mapping is now beginning to unlock the physics of the Broad Emission Line Region (BELR) in nearby, low-luminosity quasars, howe

  76. T. D. Kitching, A. N. Taylor

    We present a new method that deals with the uncertainty in matter-clustering in cosmic shear power spectrum analysis that arises mainly due to poorly understood nonlinear baryonic processes on small-scales. We show that the majority of information about dark energy physics contained in the shear power comes from these small-scales; removing these nonlinear s

  77. Osamu Yasuda

    Some attempts which were made to explain the MINOS anomaly are critically discussed. They include the non-standard neutral current-neutrino interaction and the (3+1)-scheme with sterile neutrino.

  78. Carlos A. Riofrío, Poul S. Jessen, Ivan H. Deutsch

    Quantum state reconstruction based on weak continuous measurement has the advantage of being fast, accurate, and almost non-perturbative. In this work we present a pedagogical review of the protocol proposed by Silberfarb et al., PRL 95 030402 (2005), whereby an ensemble of identically prepared systems is collectively probed and controlled in a time-dependen

  79. Guillaume Desjardins, Aaron Courville, Yoshua Bengio

    Restricted Boltzmann Machines (RBM) have attracted a lot of attention of late, as one the principle building blocks of deep networks. Training RBMs remains problematic however, because of the intractibility of their partition function. The maximum likelihood gradient requires a very robust sampler which can accurately sample from the model despite the loss o

  80. Yanqin Wu, Yoram Lithwick

    In a planetary system with two or more well-spaced, eccentric, inclined planets, secular interactions may lead to chaos. The innermost planet may gradually become very eccentric and/or inclined, as a result of the secular degrees of freedom drifting towards equipartition of angular momentum deficit. Secular chaos is known to be responsible for the eventual d

  81. Marco Piani, David Pitkanen, Rainer Kaltenbaek, Norbert Lutkenhaus

    We propose and theoretically study a method for the stochastic realization of arbitrary quantum channels on multimode single-photon qudits. In order for our method to be undemanding in its implementation, we restrict our analysis to linear-optical techniques, vacuum ancillary states and non-adaptive schemes, but we allow for random switching between differen

  82. Jurjen F. Koksma, W. Westra

    The Feynman propagator used in the conventional in-out formalism in quantum field theory is not a causal propagator as wave packets are propagated virtually instantaneously outside the causal region of the initial state. We formulate a causal in-out formalism in quantum field theory by making use of the Wheeler propagator, the time ordered commutator propaga

  83. W. Westra

    We put forward an interpretation of scalar quantum field theory as relativistic quantum mechanics by curing well known problems related to locality. A probabilistic interpretation of quantum field theory similar to quantum mechanics is difficult if particle localization is defined using the Newton-Wigner position operator as it is non-local and non-covariant

  84. Hyosun Kim, Ronald E. Taam

    Beyond the main sequence solar type stars undergo extensive mass loss, providing an environment where planet and brown dwarf companions interact with the surrounding material. To examine the interaction of substellar mass objects embedded in the stellar wind of an asymptotic giant branch (AGB) star, three dimensional hydrodynamical simulations at high resolu

  85. K. Medjanik, S. A. Nepijko, H. J. Elmers, G. Schönhense

    It is demonstrated that the near-edge X-ray absorption fine structure (NEXAFS) provides a powerful local probe of functional groups in novel charge transfer (CT) compounds. Microcrystals of tetra- and hexamethoxypyrene as donors with the strong acceptor tetracyanoquinodimethane (TMPx/HMPx - TCNQy) were grown from solution via vapour diffusion in different st

  86. Marjana Ležaić, Phivos Mavropoulos, Stefan Blügel, Hubert Ebert

    Fe3Si is a ferromagnetic material with possible applications in magnetic tunnel junctions. When doped with Mn, the material shows a complex magnetic behavior, as suggested by older experiments. We employed the Korringa-Kohn-Rostoker (KKR) Green function method within density-functional theory (DFT) in order to study the alloy Fe(3-x)Mn(x)Si, with 0 < x < 1.

  87. Cameron K. McBride, Andrew J. Connolly, Jeffrey P. Gardner, Ryan Scranton

    We constrain the linear and quadratic bias parameters from the configuration dependence of the three-point correlation function (3PCF) in both redshift and projected space, utilizing measurements of spectroscopic galaxies in the Sloan Digital Sky Survey (SDSS) Main Galaxy Sample. We show that bright galaxies (M_r < -21.5) are biased tracers of mass, measured

  88. D. A. Neufeld, E. González-Alfonso, G. Melnick, R. Szczerba

    We report the preliminary results of a survey for water vapor in a sample of eight C stars with large mid-IR continuum fluxes: V384 Per, CIT 6, V Hya, Y CVn, IRAS 15194-5115, V Cyg, S Cep, and IRC+40540. This survey, performed using the HIFI instrument on board the Herschel Space Observatory, entailed observations of the lowest transitions of both ortho- and

  89. Mohammad R Nikseresht, Anil Somayaji, Anil Maheshwari

    Almost all of the current process scheduling algorithms which are used in modern operating systems (OS) have their roots in the classical scheduling paradigms which were developed during the 1970&#39;s. But modern computers have different types of software loads and user demands. We think it is important to run what the user wants at the current moment. A us

  90. Patrick Rebentrost, Sangwoo Shim, Joel Yuen-Zhou, Alán Aspuru-Guzik

    Long-lived electronic coherences in various photosynthetic complexes at cryogenic and room temperature have generated vigorous efforts both in theory and experiment to understand their origins and explore their potential role to biological function. The ultrafast signals resulting from the experiments that show evidence for these coherences result from many

  91. Chenxu He, Peter Petersen, William Wylie

    In this paper we study warped product Einstein metrics over spaces with constant scalar curvature. We call such a manifold rigid if the universal cover of the base is Einstein or is isometric to a product of Einstein manifolds. When the base is three dimensional and the dimension of the fiber is greater than one we show that the space is always rigid. We als

  92. Creighton K. Thomas, David A. Huse, A. Alan Middleton

    Recently extended precise numerical methods and droplet scaling arguments allow for a coherent picture of the glassy states of two-dimensional Ising spin glasses to be assembled. The length scale at which entropy becomes important and produces &#34;chaos&#34;, the extreme sensitivity of the state to temperature, is found to depend on the type of randomness.

  93. David Hasler, Ira Herbst

    We discuss recent results concerning the ground state of non-relativistic quantum electrodynamics as a function of a magnetic coupling constant or the fine structure constant, obtained by the authors in [12,13,14].

  94. Annick Valibouze

    This paper collects many results on galoisian ideals and Galois theory.

  95. D. Z. Turner, K. B. Nakshatrala, P. K. Notz

    The following work compares two popular mixed finite elements used to model subsurface flow and transport in heterogeneous porous media; the lowest order Raviart-Thomas element and the variational multiscale stabilized element. Comparison is made based on performance for several problems of engineering relevance that involve highly heterogenous material prop

  96. Daniel Augot, Morgan Barbier, Alain Couvreur

    We study the list-decoding problem of alternant codes, with the notable case of classical Goppa codes. The major consideration here is to take into account the size of the alphabet, which shows great influence on the list-decoding radius. This amounts to compare the \emph{generic} Johnson bound to the \emph{$q$-ary} Johnson bound. This difference is importan

  97. Katie M Russell, Bernd J Schroers

    We present a systematic approach to the linearised Yang-Mills-Higgs equations in the background of a &#39;t Hooft-Polyakov monopole and use it to unify and extend previous studies of their spectral properties. We show that a quaternionic formulation allows for a compact and efficient treatment of the linearised equations in the BPS limit of vanishing Higgs s

  98. Gustavo Rivera, Fernando González-Nilo, Tomás Perez-Acle, Raul Isea

    The Virtual Institute for Integrative Biology (VIIB) is a Latin American initiative for achieving global collaborative e-Science in the areas of bioinformatics, genome biology, systems biology, metagenomics, medical applications and nanobiotechnolgy. The scientific agenda of VIIB includes: construction of databases for comparative genomics, the AlterORF data

  99. Lan Luan, Thomas M. Lippman, Clifford W. Hicks, Julie A. Bert

    We measure the penetration depth $λ_{ab}(T)$ in Ba(Fe$_{1-x}$Co$_{x}$)$_2$As$_2$ using local techniques that do not average over the sample. The superfluid density $ρ_s(T)\equiv1/λ_{ab}(T)^2$ has three main features. First, $ρ_s(T=0)$ falls sharply on the underdoped side of the dome. Second, $λ_{ab}(T)$ is flat at low $T$ at optimal doping, indicating fully

  100. Claude Cibils, Maria Julia Redondo, Andrea Solotar

    Let $k$ be a commutative ring. We study the behaviour of coverings of $k$-categories through fibre products and find a criterion for a covering to be Galois or universal.