October 2008 arXiv papers — page 41

H. Ikeda, S. Shinkai, K. Yamada

We investigate the Hubbard model on a two-dimensional square lattice by the perturbation expansion to the fourth order in the on-site Coulomb repulsion U. Numerically calculating all diagrams up to the fourth order in self-energy, we examine the convergence of perturbation series in the lattice system. We indicate that the coefficient of each order term rapi

Morten S. Larsen

We show how there is a natural action on the cohomology groups attached to certain subgroups of GL_n(F) of the Hecke operators defined as elements in an adelic double coset algebra. Our main result is, that if a system of eigenvalues for Hecke operators occur in the cohomology groups with coefficients in certain modules, then by changing the groups the syste

Sunil Nair, M. Nicklas, J. L. Sarrao, J. D. Thompson

We present an overview of magnetotransport measurements on the heavy-fermion superconductor CeIrIn$_5$. Sensitive measurements of the Hall effect and magnetoresistance (MR) are used to elucidate the low temperature phase diagram of this system. The normal-state magnetotransport is highly anomalous, and experimental signatures of a pseudogap-like precursor st

Stéphane Faure, T. Guillet, P. Lefebvre, T. Bretagnon

Wide bandgap semiconductors are attractive candidates for polariton-based devices operating at room temperature. We present numerical simulations of reflectivity, transmission and absorption spectra of bulk GaAs, GaN and ZnO microcavities, in order to compare the particularities of the strong coupling regime in each system. Indeed the intrinsic properties of

Abla Kammoun, Malika Kharouf, Walid Hachem, Jamal Najim

This paper is devoted to the performance study of the Linear Minimum Mean Squared Error estimator for multidimensional signals in the large dimension regime. Such an estimator is frequently encountered in wireless communications and in array processing, and the Signal to Interference and Noise Ratio (SINR) at its output is a popular performance index. The SI

Mladen Dimitrov, Louise Nyssen

Let F be a finite extension of Qp and G be GL(2,F). When V is the tensor product of three admissible, irreducible, finite dimensional representations of G, the space of G-invariant linear forms has dimension at most one. When a non zero linear form exists, one wants to find an element of V which is not in its kernel: this is a test vector. Gross and Prasad f

Sunil Nair, M. Nicklas, J. L. Sarrao, J. D. Thompson

We present an analysis of the normal state magnetotransport in the heavy fermion superconductor CeIrIn${_5}$. The Hall effect and the transverse magnetoresistance in this material do not appear to be uniquely correlated, as inferred from the field dependence of the current ratio ($R_σ = σ_{xy} / σ_{xx}^2 H$). The Hall coefficient is seen to satisfy a scaling

Jean-Marc Richard, Xavier Artru, Mokhtar Elchikh, Jacques Soffer

Positivity constrains the allowed domain for sets of spin observables in exclusive or inclusive reactions. Examples are given for strangeness-echange reactions and photoproduction.

S. Mathur, S. J. Jimenez-Reyes, R. A. Garcia

Solar magnetism is measured with different indexes: for instance the MPSI and the MWSI, number of sunspots, radio flux at 10.7 cm, Ca II K, Mg II K, EUV, He I or L_alpha. Bachmann & White (1994) had compared these indicators of the solar activity showing a hysteresis of the solar cycle variations and a time lag between these indices not related to instrument

V. N. Baier, V. M. Katkov

The process of electroproduction of the electron-positron pair by high energy electron in an oriented single crystal is investigated. Two contributions are considered: the direct (one-step) process via the virtual intermediate photon and the cascade(two-step) process when the electron emits the real photon moving in the field of axis and afterwards the photo

Federico Hernandez-Sanchez, Rene Ledesma, Roberto Zenit

This is an entry for the Gallery of Fluid Motion of the 61st Annual Meeting of the APS-DFD (fluid dynamics videos). This video shows the collision and rebound of viscoelastic drops against a solid wall. Using a high speed camera, the process of approach, contact and rebound of drops of a viscoelastic liquid is observed. We found that these drops first splash

Hongbin Sun, Shicheng Wang, Jianchun Wu

Each closed oriented 3-manifold $M$ is naturally associated with a set of integers $D(M)$, the degrees of all self-maps on $M$. $D(M)$ is determined for each torus bundle and torus semi-bundle $M$. The structure of torus semi-bundle is studied in detail. The paper is a part of a project to determine $D(M)$ for all 3-manifolds in Thurston's picture.

Amos G. Winter, V Anette E. Hosoi

This fluid dynamics video demonstrates the capabilities of an experimental setup to visualize organisms burrowing in granular substrates. The setup consists of a tank filled with 1mm soda-lime glass beads, backlit by halogen lights. The walls can be moved such that the space bound by them can expand or contract to fit various organisms. A recirculation syste

Changsheng Shi, Xiang-Dong Li

We suggest an explanation for the twin kilohertz quasi-periodic oscillations (kHz QPOs) in low-mass X-ray binaries (LMXBs) based on magnetohydrodynamics (MHD) oscillation modes in neutron star magnetospheres. Including the effect of the neutron star spin, we derive several MHD wave modes by solving the dispersion equations, and propose that the coupling of t

Hisayuki Hara, Akimichi Takemura, Ruriko Yoshida

In this paper we consider exact tests of a multiple logistic regression, where the levels of covariates are equally spaced, via Markov beses. In usual application of multiple logistic regression, the sample size is positive for each combination of levels of the covariates. In this case we do not need a whole Markov basis, which guarantees connectivity of all

A. Denbleyker, Daping Du, Yuzhi Liu, Y. Meurice

We study the location of the partition function zeros in the complex beta plane (Fisher's Zeros) for SU(2) lattice gauge theory on L^4 lattices. We discuss recent attempts to locate complex zeros for L=4 and 6. We compare results obtained using various polynomial approximations of the logarithm of the density of states and a straightforward MC reweighting. W

Takashi Torii, Hisa-aki Shinkai

Towards the investigation of the full dynamics in higher-dimensional and/or stringy gravitational model, we present the basic equations of the Einstein-Gauss-Bonnet gravity theory. We show $(N+1)$-dimensional version of the ADM decomposition including Gauss-Bonnet terms, which shall be the standard approach to treat the space-time as a Cauchy problem. Due to

Fritz Gesztesy, Mark M. Malamud

We consider various closed (and self-adjoint) extensions of elliptic differential expressions of the type $\cA=\sum_{0\le |α|,|β|\le m}(-1)^αD^αa_{α, β}(x)D^β$, $a_{α, β}(\cdot)\in C^{\infty}({\overlineΩ})$, on smooth (bounded or unbounded) domains in $\bbR^n$ with compact boundary. Using the concept of boundary triples and operator-valued Weyl-Titchmarsh fu

Dagim Tilahun, Gregory A. Fiete

We discuss the properties of a strongly interacting spin-charge separated one dimensional system coupled to ferromagnets and/or superconductors. Our results are valid for arbitrary temperatures with respect to the spin energy, but require temperature be small compared to the charge energy. We focus mainly on the spin-incoherent regime where temperature is la

Ines Cavero-Pelaez, Kimball A. Milton, Prachi Parashar, K. V. Shajesh

We derive explicit analytic expressions for the lateral force for two different configurations with corrugations, parallel plates and concentric cylinders. By making use of the multiple scattering formalism, we calculate the force for a scalar field under the influence of a delta-function potential that has sinusoidal dependence in one direction simulating t

Ines Cavero-Pelaez, Kimball A. Milton, Prachi Parashar, K. V. Shajesh

In this paper we are giving a quantitative description of two different configurations for noncontact gears. We consider the solutions from a perturbative calculation for two semitransparent parallel plates and concentric cylinders both with corrugations on the inner surfaces. In the case of corrugated parallel plates we discuss results from first- and secon

Robin Koytcheff

We construct cohomology classes in the space of knots by considering a bundle over this space and "integrating along the fiber" classes coming from the cohomology of configuration spaces using a Pontrjagin-Thom construction. The bundle we consider is essentially the one considered by Bott and Taubes, who integrated differential forms along the fiber

F. J. Burnell, B. Andrei Bernevig, D. P. Arovas

We investigate the possibility of a strongly correlated Fractional Quantum Hall (FQH) state in bulk three dimensional isotropic (not layered) materials. We find that a FQH state can exist at low densities only if it is accompanied by a staging transition in which the electrons re-organize themselves in layers, perpendicular to the magnetic field, at distance

Michael Kiermaier, Yuji Okawa, Barton Zwiebach

We construct a class of BRST-invariant closed string states for any classical solution of open string field theory. The closed string state is a nonlinear functional of the open string field and changes by a BRST-exact term under a gauge transformation of the solution. As a result, its contraction with an on-shell closed string state provides a gauge-invaria

Daniel A. Ramras

We compute the homotopy type of the moduli space of flat, unitary connections over aspherical surfaces, after stabilizing with respect to the rank of the underlying bundle. Over the orientable surface M^g, we show that this space has the homotopy type of the infinite symmetric product of M^g, generalizing a well-known fact for the torus. Over a non-orientabl

Joel Spruck, Bo Guan

We find complete hypersurfaces of constant curvature in hyperbolic space with a prescribed asymptotic boundary at infinity for a general class of (elliptic) curvature functions which includes the higher order mean curvatures and their curvature quotients.

Joel Spruck, Bo Guan, Marek Szapiel

We investigate the problem of finding complete strictly convex hypersurfaces of constant curvature in hyperbolic space with a prescribed asymptotic boundary at infinity for a general class of curvature functions.

David Klein, Peter Collas

For spacetimes with timelike Killing fields, we introduce a "Fermi-Walker-Killing" coordinate system and use it to prove a Liouville Theorem for an appropriate volume element of phase space for a statistical mechanical system of particles. We derive an exact relativistic formula for the Helmholtz free energy of an ideal gas and compare it, for a clas

Matej Bresar, Igor Klep

A subspace of an algebra with involution is called a Lie skew-ideal if it is closed under Lie products with skew-symmetric elements. Lie skew-ideals are classified in central simple algebras with involution (there are eight of them for involutions of the first kind and four for involutions of the second kind) and this classification result is used to charact

Y. Chen, B. G. Ueland, J. W. Lynn, G. L. Bychkov

The nature of the polarons in the optimally doped colossal magnetoresistive (CMR) materials La0.7Ba0.3MnO3 (LBMO) and La0.7Sr0.3MnO3 (LSMO) is studied by elastic and inelastic neutron scattering. In both materials, dynamic nanoscale polaron correlations develop abruptly in the ferromagnetic state. However, the polarons are not able to lock-in to the lattice

T. A. Costi, L. Bergqvist, A. Weichselbaum, J. von Delft

We exploit the decoherence of electrons due to magnetic impurities, studied via weak localization, to resolve a longstanding question concerning the classic Kondo systems of Fe impurities in the noble metals gold and silver: which Kondo-type model yields a realistic description of the relevant multiple bands, spin and orbital degrees of freedom? Previous stu

David Rideout, Petros Wallden

Any discrete approach to quantum gravity must provide some prescription as to how to deduce continuum properties from the discrete substructure. In the causal set approach it is straightforward to deduce timelike distances, but surprisingly difficult to extract spacelike distances, because of the unique combination of discreteness with local Lorentz invarian

Mark A. Scheel, Michael Boyle, Tony Chu, Lawrence E. Kidder

The first spectral numerical simulations of 16 orbits, merger, and ringdown of an equal-mass non-spinning binary black hole system are presented. Gravitational waveforms from these simulations have accumulated numerical phase errors through ringdown of ~0.1 radian when measured from the beginning of the simulation, and ~0.02 radian when waveforms are time an

James F. Steiner, Ramesh Narayan, Jeffrey E. McClintock, Ken Ebisawa

We present an empirical model of Comptonization for fitting the spectra of X-ray binaries. This model, "simpl", has been developed as a package implemented in XSPEC. With only two free parameters, simpl is competitive as the simplest empirical model of Compton scattering. Unlike other empirical models, such as the standard power-law model, simpl inco

Milan Bradonjic, Eddie Kohler, Rafail Ostrovsky

We consider the model of communication where wireless devices can either switch their radios off to save energy, or switch their radios on and engage in communication. We distill a clean theoretical formulation of this problem of minimizing radio use and present near-optimal solutions. Our base model ignores issues of communication interference, although we

Oscar Agertz, George Lake, Romain Teyssier, Ben Moore

Observations of turbulent velocity dispersions in the HI component of galactic disks show a characteristic floor in galaxies with low star formation rates and within individual galaxies the dispersion profiles decline with radius. We carry out several high resolution adaptive mesh simulations of gaseous disks embedded within dark matter haloes to explore the

I. Titvinidze, M. Snoek, W. Hofstetter

We give a detailed discussion of the recently developed Generalized Dynamical Mean-Field Theory (GDMFT) for a mixture of bosonic and fermionic particles. We show that this method is non-perturbative and exact in infinite dimensions and reliably describes the full range from weak to strong coupling. Like in conventional Dynamical Mean-Field Theory, the small

Andrea V. Maccio', Xi Kang, Ben Moore

It has been pointed out that the Galactic satellites all have a common mass around 1e7 Msun within 300 pc (M03), while they span almost four order of magnitudes in luminosity (Mateo et al. 1993, Strigari et al. 2008). It is argued that this may reflect a specific scale for galaxy formation or a scale for dark matter clustering. Here we use numerical simulati

Jan Perz, Paul Smyth, Thomas Van Riet, Bert Vercnocke

We derive a general form of first-order flow equations for extremal and non-extremal, static, spherically symmetric black holes in theories with massless scalars and vectors coupled to gravity. By rewriting the action as a sum of squares a la Bogomol'nyi, we identify the function governing the first-order gradient flow, the `generalised superpotential&#3

Jens Braun

We study one-flavor QCD at finite temperature and chemical potential using the functional renormalization group. We discuss the chiral phase transition in QCD and its order with its underlying mechanism in terms of quarks and gluons and analyze the dependence of the phase transition temperature on small quark chemical potentials. Our result for the curvature

E. Rufeil Fiori, C. M. Sanchez, F. Y. Oliva, H. M. Pastawski

A suitable NMR experiment in a one-dimensional dipolar coupled spin system allows one to reduce the natural many-body dynamics into effective one-body dynamics. We verify this in a polycrystalline sample of hydroxyapatite (HAp) by monitoring the excitation of NMR many-body superposition states: the multiple-quantum coherences. The observed effective one-dime

Z. Staniszewski, P. A. R. Ade, K. A. Aird, B. A. Benson

The South Pole Telescope (SPT) is conducting a Sunyaev-Zel'dovich (SZ) effect survey over large areas of the southern sky, searching for massive galaxy clusters to high redshift. In this preliminary study, we focus on a 40 square-degree area targeted by the Blanco Cosmology Survey (BCS), which is centered roughly at right ascension 5h30m, declination -53

A. A. Grib, Yu. V. Pavlov

The hypothesis that dark matter is converted into visible particles in active galactic nuclei is investigated. If dark matter consists of stable superheavy neutral particles and active galactic nuclei are rotating black holes, then, due to the Penrose process, superheavy particles can decay into unstable particles with larger mass, whose decay into quarks an

James A. Hart, Thomas M. Antonsen, Edward Ott, Stephen M. Anlage

The ensemble averaged power scattered in and out of lossless chaotic cavities decays as a power law in time for large times. In the case of a pulse with a finite duration, the power scattered from a single realization of a cavity closely tracks the power law ensemble decay initially, but eventually transitions to an exponential decay. In this paper, we explo

Igor Khavkine

Merged into arXiv:0809.3190.

F. R. Klinkhamer

This contribution reviews recent work on a new approach to the cosmological constant problem, which starts from the macroscopic behavior of a conserved relativistic microscopic variable q. First, the statics of the vacuum energy density is discussed and, then, the dynamics in a cosmological context.

Xander Faber, Benjamin Hutz, Michael Stoll

For a quadratic endomorphism of the affine line defined over the rationals, we consider the problem of bounding the number of rational points that eventually land at the origin after iteration. In the article ``Uniform Bounds on Pre-Images Under Quadratic Dynamical Systems,'' by two of the present authors and five others, it was shown that the number

Claudio Perini, Carlo Rovelli, Simone Speziale

We consider the elementary radiative-correction terms in loop quantum gravity. These are a two-vertex "elementary bubble" and a five-vertex "ball"; they correspond to the one-loop self-energy and the one-loop vertex correction of ordinary quantum field theory. We compute their naive degree of (infrared) divergence.

Yu. B. Gaididei, A. P. Krekhov, H. Buettner

A theory of photoinduced directed bending of non-crystalline molecular films is presented. Our approach is based on elastic deformation of the film due to interaction between molecules ordered through polarized light irradiation. The shape of illuminated film is obtained in the frame of the nonlinear elasticity theory. It is shown that the shape and the curv

K. F. Pál, T. Vértesi

We have determined the maximum quantum violation of 241 tight bipartite Bell inequalities with up to five two-outcome measurement settings per party by constructing the appropriate measurement operators in up to six-dimensional complex and eight-dimensional real component Hilbert spaces using numerical optimization. Out of these inequalities 129 has been int

A. Di Piazza, K. Z. Hatsagortsyan, C. H. Keitel

The influence of radiation reaction (RR) on multiphoton Thomson scattering by an electron colliding head-on with a strong laser beam is investigated in a new regime, in which the momentum transferred on average to the electron by the laser pulse approximately compensates the one initially prepared. This equilibrium is shown to be far more sensitive to the in

R. Smiljanic, R. Gauderon, P. North, B. Barbuy

Evolved low-mass stars of a wide range of metallicity bear signatures of a non-standard mixing event in their surface abundances of Li, C, and N, and in their 12C/13C ratio. A Na overabundance has also been reported in some giants of open clusters but remains controversial. The cause of the extra-mixing has been attributed to thermohaline convection that sho

William D. Kirwin

We present expressions for the coefficients which arise in asymptotic expansions of multiple integrals of Laplace type (the first term of which is known as Laplace's approximation) in terms of asymptotic series of the functions in the integrand. Our most general result assumes no smoothness of the functions of the integrand, but the expressions we obtain

D. Salabert, R. A. Garcia

In the case of spatially-revolved helioseismic data (such as MDI, GONG, HMI), the usual mode-fitting analysis consists of fitting the 2l+1 individual m-spectra of a given multiplet (n, l) either individually or simultaneously. Such fitting methods fail to obtain reliable estimates of the mode parameters (frequency, splitting, ...) when the signal-to-noise ra

I. F. Ginzburg

Most general renormalizable interaction in the system with a set of scalar fields having identical quantum numbers generates naturally mixed kinetic terms in the Lagrangian. Taking into account these terms leads to modification both the renormalization group equations and the tree level analysis as compare with many published results. We obtain conditions fo

R. J. Stoehr, G. J. Beirne, P. Michler, R. Scholz

The exciton dynamics on flat (001) rubrene crystal surfaces have been compared with those under confined pyramidal geometry by time-resolved photoluminescence with micrometer spatial resolution. The luminescence spectra can be interpreted in terms of generation of a free and a self-trapped exciton. Their ratio depends significantly on the structural size whi

Shigenori Seki, Jacob Sonnenschein

We generalize the description of baryons as instantons of Sakai-Sugimoto model to the case where the flavor branes are non-anti-podal. The later corresponds to quarks with a "string endpoint mass". We show that the baryon vertex is located on the flavor branes and hence the generalized baryons also associate with instantons. We calculate the baryon m

Mubasher Jamil, Umar Farooq

We examine the problem of the gravitational collapse using higher dimensional Husain spacetime for the null fluid. The equations of state chosen to solve the field equations contain linear, quadratic and arbitrary powers of the radial parameter. The resulting mass evolution is discussed for each case.

A. Lindote, H. M. Araujo, V. A. Kudryavtsev, M. Robinson

This article describes the Monte Carlo simulation used to interpret the measurement of the muon-induced neutron flux in the Boulby Underground Laboratory (North Yorkshire, UK), recently performed using a large scintillator veto deployed around the ZEPLIN-II WIMP detector. Version 8.2 of the GEANT4 toolkit was used after relevant benchmarking and validation o

Suzanne Lynch Hruska, Roland K. W. Roeder

Little is known about the global topology of the Fatou set $U(f)$ for holomorphic endomorphisms $f: \mathbb{CP}^k \to \mathbb{CP}^k$, when $k >1$. Classical theory describes $U(f)$ as the complement in $ \mathbb{CP}^k$ of the support of a dynamically-defined closed positive $(1,1)$ current. Given any closed positive $(1,1)$ current $S$ on $ \mathbb{CP}^k$, w

Sergei Alexandrov, Boris Pioline, Frank Saueressig, Stefan Vandoren

We extend the twistor methods developed in our earlier work on linear deformations of hyperkahler manifolds [arXiv:0806.4620] to the case of quaternionic-Kahler manifolds. Via Swann's construction, deformations of a 4d-dimensional quaternionic-Kahler manifold $M$ are in one-to-one correspondence with deformations of its $4d+4$-dimensional hyperkahler con

D. S. Covita, D. F. Anagnostopoulos, H. Gorke, D. Gotta

The (3p - 1s) X-ray transition to the muonic hydrogen ground state was measured with a high resolution crystal spectrometer. A Doppler effect broadening of the X-ray line was established which could be attributed to different Coulomb de-excitation steps preceding the measured transition. The assumption of a statistical population of the hyperfine levels of t

A. Eichler, R. Deblock, M. Weiss, C. Karrasch

We investigate the Josephson current in a single wall carbon nanotube connected to superconducting electrodes. We focus on the parameter regime in which transport is dominated by Kondo physics. A sizeable supercurrent is observed for odd number of electrons on the nanotube when the Kondo temperature Tk is sufficiently large compared to the superconducting ga

David Seery

The primordial density fluctuation inevitably couples to all forms of matter via loop corrections and depends on the ambient conditions while inflation was ongoing. This gives us an opportunity to observe processes which were in progress while the universe was inflating, provided they were sufficiently dramatic to overcome suppression by powers of (H/MP)^2 ~

Xiaopeng Chen, Jinqiao Duan

It is known by the Conley's theorem that the chain recurrent set $CR(ϕ)$ of a deterministic flow $ϕ$ on a compact metric space is the complement of the union of sets $B(A)-A$, where $A$ varies over the collection of attractors and $B(A)$ is the basin of attraction of $A$. It has recently been shown that a similar decomposition result holds for random dyn

P. A. Boyle, D. Brömmel, M. A. Donnellan, J. M. Flynn

We present results for the first two moments of the light-cone distribution amplitudes of the pion and kaon pseudo-scalar mesons and of the rho, K* and phi vector mesons. The calculations are performed on the RBC/UKQCD collaborations' ensembles generated with the Iwasaki gauge action and with 2+1 flavours of domain wall fermions. In addition we also provide

O. C. de Jager, P. O. Slane, S. LaMassa

Morphologically it appears as if the Vela X PWN consists of two emission regions: whereas X-ray (1 keV) and very high energy (VHE) H.E.S.S. gamma-ray observations appear to define a cocoon type shape south of the pulsar, radio observations reveal an extended area of size 2 deg by 3 deg (including the cocoon area), also south of the Vela pulsar. Since no wide

Moshe Marcus, Laurent Veron

We study the existence and uniqueness of new classes of solutions of the superlinear equation $-Δu+u^q=0$ (q>1) in a domain of R^N or in a finely open set for the topology associated to the Bessel capacity C_{2,q'}. Condition of existence or uniqueness of solutions with boundary blow-up are obtained generalizing the results of Dhersin-Le Gall and of Labu

Hsien-Hang Shieh, Greg van Anders

Recently, a mechanism for the development of a fermi surface in a holographic model of large N QCD with a baryon chemical potential was proposed. We examine similar constructions to determine when this mechanism persists. We find a class of models in which it does.

Sayantani Bhattacharyya, Shiraz Minwalla, Spenta R. Wadia

We note that the equations of relativistic hydrodynamics reduce to the incompressible Navier-Stokes equations in a particular scaling limit. In this limit boundary metric fluctuations of the underlying relativistic system turn into a forcing function identical to the action of a background electromagnetic field on the effectively charged fluid. We demonstrat

Kingman Cheung, Wai-Yee Keung, Tzu-Chiang Yuan

Phenomenology of uncolored iquarks - hypothetical fermions charged under a new confining unbroken non-abelian gauge group as well as the standard electroweak gauge group - is investigated for the iquark mass in the range near and above 100 GeV. If the new confining scale turns out to be higher than MeV but much less than the iquark mass, the iquark-antiiquar

Melanie Pfeuffer, Gunnar S. Bali, Marco Panero

In quenched QCD, where the dynamic creation of quark-antiquark pairs out of the vacuum is neglected, a confined baryonic system composed of three static quarks exhibits string-like behaviour at large interquark separation, with the formation of flux tubes characterized by the geometry of the so-called Y ansatz. We study the fluctuations of the junction of th

Dana Bartosova, Logan Hoehn, Klaas Pieter Hart, Berd van der Steeg

We show that Lelek's problem on the chainability of continua with span zero is not a metric problem: from a non-metric counterexample one can construct a metric one.

Robert M. Ziff, Satya N. Majumdar, Alain Comtet

It is shown that particles undergoing discrete-time jumps in 3D, starting at a distance r0 from the center of an adsorbing sphere of radius R, are captured with probability (R - c sigma)/r0 for r0 much greater than R, where c is related to the Fourier transform of the scaled jump distribution and sigma is the distribution's root-mean square jump length.

F. Belgiorno, S. L. Cacciatori

We consider the behavior of massive Dirac fields on the background of a charged de-Sitter black hole. All black hole geometries are taken into account, including the Reissner-Nordström-de-Sitter one, the Nariai case and the ultracold case. Our focus is at first on the existence of bound quantum mechanical states for the Dirac Hamiltonian on the given backgro

Eaman Eftekhary

Given a symplectic three-fold $(M,ω)$ we show that for a generic almost complex structure $J$ which is compatible with $ω$, there are finitely many $J$-holomorphic curves in $M$ of any genus $g\geq 0$ representing a homology class $β$ in $\H_2(M,\Z)$ with $c_1(M).β=0$, provided that the divisibility of $β$ is at most 4 (i.e. if $β=nα$ with $α\in H_2(M,\Z)$ a

D. A. Smith, L. Guillemot, F. Camilo, I. Cognard

We describe a comprehensive pulsar monitoring campaign for the Large Area Telescope (LAT) on the {\em Fermi Gamma-ray Space Telescope} (formerly GLAST). The detection and study of pulsars in gamma rays give insights into the populations of neutron stars and supernova rates in the Galaxy, into particle acceleration mechanisms in neutron star magnetospheres, a

V. S. Shchesnovich

A light pulse propagating in a suddenly switched on photonic lattice, when the central frequency lies in the photonic band gap, is an analog of the Rabi model where the two-level system is the two resonant (i.e. Bragg-coupled) Fourier modes of the pulse, while the photonic lattice serves as a monochromatic external field. A simple theory of these Rabi oscill

V. M. Khatsymovsky

Regge calculus minisuperspace action in the connection representation has the form in which each term is linear over some field variable (scale of area-type variable with sign). We are interested in the result of performing integration over connections in the path integral (now usual multiple integral) as function of area tensors even in larger region consid

Kyriakos Hizanidis, Yannis Kominis, Nikolaos K. Efremidis

The system of coupled discrete equations describing a two-component superlattice with interlaced linear and nonlinear constituents is revisited as a basis for investigating binary waveguide arrays, such as ribbed AlGaAs structures, among others. Compared to the single nonlinear lattice, the interlaced system exhibits an extra band-gap controlled by the, suit

A. M. Mosquera, J. A. Muñoz, E. Mediavilla

We present narrowband images of the gravitational lens system Q~2237+0305 made with the Nordic Optical Telescope in eight different filters covering the wavelength interval 3510-8130 Å. Using point-spread function photometry fitting we have derived the difference in magnitude versus wavelength between the four images of Q~2237+0305. At $λ=4110$ Å, the wavele

Lu-Jing Hou, Alexander Piel

We perform non-equilibrium simulations to study heat conduction in two-dimensional strongly coupled dusty plasmas. Temperature gradients are established by heating one part of the otherwise equilibrium system to a higher temperature. Heat conductivity is measured directly from the stationary temperature profile and heat flux. Particular attention is paid to

Kenneth L. Pryor

A suite of products has been developed and evaluated to assess hazards presented by convective downbursts to aircraft in flight derived from the current generation of GOES. The existing suite of GOES microburst products employs the sounder to calculate risk based on conceptual models of favorable environmental profiles for convective downburst generation. Ac

Andreas Crivellin, Ulrich Nierste

We compute the finite renormalisation of the Cabibbo-Kobayashi-Maskawa (CKM) matrix induced by gluino-squark diagrams in the MSSM with non-minimal sources of flavour violation. Subsequently we derive bounds on the flavour-off-diagonal elements of the squark mass matrices by requiring that the radiative corrections to the CKM elements do not exceed the experi

Jean Vallès

We propose a generalization of logarithmic and Schwarzenberger bundles over $¶^n=¶^n(\C)$ when the rank is greater than $n$. The first ones are associated to finite sets of points on $¶^{n\vee}$ and the second ones to curves with degree greater than $n$ on $¶^{n\vee}$. On the projective plane we show that two logarithmic bundles are isomorphic if and only if

Tomoaki Nogawa, Takehisa Hasegawa

We perform Monte-Carlo simulations to study the Bernoulli ($p$) bond percolation on the enhanced binary tree which belongs to the class of nonamenable graphs with one end. Our numerical results show that the system has two different percolation thresholds $p_{c1}$ and $p_{c2}$. All the points in the intermediate phase $(p_{c1} < p < p_{c2})$ are critical and

Yan-Rui Liu, Zong-Ye Zhang

We investigated systematically whether the S-wave ($\bar{Q}q$) meson and the ($Q\bar{q}$) meson may form S-wave bound states in a chiral SU(3) quark model by solving the resonating group method equation. Here $Q=c$ or $b$ and $q=u$, $d$ or $s$. Our preliminary calculation disfavors the existence of $I=\frac12$ ($\bar{Q}l$)-($Q\bar{s}$) molecules ($l=u,d$) wh

Sheng-Chang Li, Li-Bin Fu, Wen-Shan Duan, Jie Liu

We propose a feasible scheme to realize nonlinear Ramsey interferometry with a two-component Bose-Einstein condensate, where the nonlinearity arises from the interaction between coherent atoms. In our scheme, two Rosen-Zener pulses are separated by an intermediate holding period of variable duration and through varying the holding period we have observed nic

Guowu Yao

Let $\mathbb{H}^n$ be the $n-$dimensional hyperbolic space. It is well known that, if $f: \mathbb{H}^n\to \mathbb{H}^n$ is a bijection that preserves $r-$dimensional hyperplanes, then $f$ is an isometry. In this paper we make neither injectivity nor $r-$hyperplane preserving assumptions on $f$ and prove the following result: Suppose that $f: \mathbb{H}^n\to

Masahiro Kawasaki, Kazunori Nakayama, Fuminobu Takahashi

We study non-Gaussianity induced by a pseudo Nambu-Goldstone boson with a cosine-type scalar potential. We focus on how the non-Gaussianity is affected when the pseudo Nambu-Goldstone boson rolls down from near the top of the scalar potential where the deviation from a quadratic potential is large. We find that the resultant non-Gaussianity is similar to tha

Nikos Frantzikinakis, Michael Johnson, Emmanuel Lesigne, Mate Wierdl

A sequence $(s_n)$ of integers is good for the mean ergodic theorem if for each invertible measure preserving system $(X,\mathcal{B},μ,T)$ and any bounded measurable function $f$, the averages $ \frac1N \sum_{n=1}^N f(T^{s_n}x)$ converge in the $L^2$ norm. We construct a sequence $(s_n)$ that is good for the mean ergodic theorem, but the sequence $(s_n^2)$ i

Hyojune Lee, Shantha Vedantam, Japeck Tang, Josh Conway

Focusing electromagnetic energy to sub-wavelength dimensions has become an increasingly active field of research for a variety of applications such as Heat Assisted Magnetic Recording (HAMR), nanolithography, and nanoscale optical characterization of biological cells and single molecules using near-field scanning optical microscopy (NSOM) technique. Double-s

Joachim Stubbe

We show that phase space bounds on the eigenvalues of Schrödinger operators can be derived from universal bounds recently obtained by E. M. Harrell and the author via a monotonicity property with respect to coupling constants. In particular, we provide a new proof of sharp Lieb-Thirring inequalities.

Thomas Vojta, Adam Farquhar, Jason Mast

We study the nonequilibrium phase transition in the two-dimensional contact process on a randomly diluted lattice by means of large-scale Monte-Carlo simulations for times up to $10^{10}$ and system sizes up to $8000 \times 8000$ sites. Our data provide strong evidence for the transition being controlled by an exotic infinite-randomness critical point with a

T. Umeda, H. Ohno, K. Kanaya

Dissociation temperatures of J/\psi, \psi', and \chi_c states play key roles in the sequential J/\psi suppression scenario for high energy heavy ion collisions. We report on a study of charmonium dissociation temperatures in quenched lattice QCD. On anisotropic lattices, we first subtract the effects of the constant mode in finite temperature meson correlato

Erez Berg, Eduardo Fradkin, Steven A. Kivelson

We define a distinct phase of matter, a &#34;pair density wave&#34; (PDW), in which the superconducting order parameter $ϕ$ varies periodically as a function of position such that when averaged over the center of mass position, all components of $ϕ$ vanish identically. Specifically, we study the simplest, unidirectional PDW, the &#34;striped superconductor,&

C. M. Chandrashekar

The study of quantum walk processes has been widely divided into two standard variants, the discrete-time quantum walk (DTQW) and the continuous-time quantum walk (CTQW). The connection between the two variants has been established by considering the limiting value of the coin operation parameter in the DTQW, and the coin degree of freedom was shown to be un

Matthew Luzum, Gerald A. Miller

The effect of final state interactions on the elliptic flow coefficient measured in relativistic heavy ion collisions is investigated within the DWEF formalism established by Miller and Cramer [Phys. Rev. Lett. 94, 102302 (2005), J. Phys. G34, 703 (2007), Phys. Rev. C78, 054905 (2008)]. It is found that the optical potential previously found to give the best

G. P. Alexander, C. M. Pooley, J. M. Yeomans

We describe the consequences of time reversal invariance of the Stokes&#39; equations for the hydrodynamic scattering of two low Reynolds number swimmers. For swimmers that are related to each other by a time reversal transformation this leads to the striking result that the angle between the two swimmers is preserved by the scattering. The result is illustr

Kwei-Chou Yang

I introduce the properties of the light axial-vector mesons. The branching ratios, longitudinal fractions and direct CP asymmetries of the related charmless two-body B decays into final states involving two axial-vector mesons ($AA$) or one vector and one axial-vector meson ($VA$) are discussed within the framework of QCD factorization.