June 2007 arXiv papers — page 6

Jasonjot S. Kalirai, Brad M. S. Hansen, Daniel D. Kelson, David B. Reitzel

The initial-final mass relation represents a mapping between the mass of a white dwarf remnant and the mass that the hydrogen burning main-sequence star that created it once had. The relation thus far has been constrained using a sample of ~40 stars in young open clusters, ranging in initial mass from ~2.75 -- 7 Msun, and shows a general trend that connects

Lutz Duembgen, Günther Walther

We introduce a multiscale test statistic based on local order statistics and spacings that provides simultaneous confidence statements for the existence and location of local increases and decreases of a density or a failure rate. The procedure provides guaranteed finite-sample significance levels, is easy to implement and possesses certain asymptotic optima

Viktor G. Czinner, Matyas Vasuth

We consider general-relativistic rotational perturbations in homogeneous and isotropic Friedman - Robertson - Walker (FRW) cosmologies. Taking linear perturbations of FRW models, the general solution of the field equations contains tensorial, vectorial and scalar functions. The vectorial terms are in connection with rotations in the given model and due to th

R. Mir, J. S. Lundeen, M. W. Mitchell, A. M. Steinberg

A which-way measurement in Young's double-slit will destroy the interference pattern. Bohr claimed this complementarity between wave- and particle behaviour is enforced by Heisenberg's uncertainty principle: distinguishing two positions a distance s apart transfers a random momentum q \sim \hbar/s to the particle. This claim has been subject to debat

Hisao Hayakawa, Michio Otsuki

The long-time behavior of the current auto-correlation functions for the velocity, the shear stress and the heat flux is investigated in freely cooling granular gases. It is found that the correlation functions for the velocity and the shear stress have the long-time tails obeying $τ^{-d/2}$, while the correlation function of heat flux decays as $τ^{-(d+2)/2

A. K. Chaudhuri

In jet quenching, a hard QCD parton, before fragmenting into a jet of hadrons, deposits a fraction of its energy in the medium, leading to suppressed production of high-$p_T$ hadrons. Assuming that the deposited energy quickly thermalizes, we simulate the subsequent hydrodynamic evolution of the QGP fluid. Hydrodynamic evolution and subsequent particle emiss

Chenyang Xu

It is known that the fundamental groups of smooth loci of Log del Pezzo Surfaces are finite groups. The aim of this note is to study these finite groups. A short table containing these groups is given. And lots of groups on the table are proved to be fundamental groups.

The Belle Collaboration, S. Uehara

We report measurements of charmonia produced in two-photon collisions and decaying to four-meson final states, where the meson is either a charged pion or a charged kaon. The analysis is based on a 395fb^{-1} data sample accumulated with the Belle detector at the KEKB electron-positron collider. We observe signals for the three C-even charmonia eta_c(1S), ch

M. L. Walker

Abelian dominance is used to reformulate the QCD Lagrangian as a sum over the roots of Lie group representation theory. This greatly facilitates extending the SU(2) magnetic ground state energy spectrum, several arguments for the stability of the magnetic ground state, and the Faddeev-Skyrme model to arbitrary SU(N) QCD.

Irina Novikova, David F. Phillips, Ronald L. Walsworth

We demonstrate slow and stored light in Rb vapor with a combination of desirable features: minimal loss and distortion of the pulse shape, and large fractional delay (> 10). This behavior is enabled by: (i) a group index that can be controllably varied during light pulse propagation; and (ii) controllable gain integrated into the medium to compensate for pul

Kunihiko Terasaki

A new tetra-quark interpretation of X(3872) is presented. In this model, X(3872) consists of two degenerate tetra-quark mesons, {[cn](cbar nbar) +- (cn)[cbar nbar]}_{I=0}, and, therefore, it is naturally understood that X(3872) decays into two different eigenstates of G-parity.

M. K. Georgoulis, Barry J. LaBonte

We self-consistently derive the magnetic energy and relative magnetic helicity budgets of a three-dimensional linear force-free magnetic structure rooted in a lower boundary plane. For the potential magnetic energy we derive a general expression that gives results practically equivalent to those of the magnetic Virial theorem. All magnetic energy and helicit

A. V. Belitsky

We study the largest particle-number-preserving sector of the dilatation operator in maximally supersymmetric gauge theory. After exploring one-loop Bethe Ansatze for the underlying spin chain with psl(2|2) symmetry for simple root systems related to several Kac-Dynkin diagrams, we use the analytic Bethe Anzats to construct eigenvalues of transfer matrices w

Andrea Alu, Nader Engheta

Connecting lumped circuit elements in a conventional circuit is usually accomplished by conducting wires that act as conduits for the conduction currents with negligible potential drops. More challenging, however, is to extend these concepts to optical nanocircuit elements. Here, following our recent development of optical lumped circuit elements, we show ho

Yanping Cao, Ziad H. Musslimani, Edriss S. Titi

A regularized $α-$system of the Nonlinear Schrödinger Equation (NLS) with $2σ$ nonlinear power in dimension $N$ is studied. We prove existence and uniqueness of local solution in the case $1 \le σ<\frac{4}{N-2}$ and existence and uniqueness of global solution in the case $1 \le σ< \frac{4}{N}$. When $α\to 0^+$, this regularized system will converge to the cl

Neal J. Evans

Using studies of nearby star formation with Spitzer, I will argue that star formation is restricted to dense cores within molecular clouds. The nature of these dense cores and their connection to star formation will be discussed. Their distribution over masses and over the cloud is similar to that of stars, and their efficiency of forming stars is much highe

S. Schnee, P. Caselli, A. Goodman, H. G. Arce

We have mapped the starless core TMC-1C in a variety of molecular lines with the IRAM 30m telescope. High density tracers show clear signs of self-absorption and sub-sonic infall asymmetries are present in N2H+ (1-0) and DCO+ (2-1) lines. The inward velocity profile in N2H+ (1-0) is extended over a region of about 7,000 AU in radius around the dust continuum

E. Sauvan

The high energy programme of the HERA collider ended in March 2007. During the whole HERA programme, a combined total integrated luminosity of 1 fb$^{-1}$ was collected by the H1 and ZEUS experiments. In this context, an overview of the most recent results of both experiments concerning searches for new physics is presented. The topics covered are searches f

E. Sauvan

A model-independent search for deviations from the Standard Model prediction is performed in $e^+ p$ and $e^- p$ collisions at HERA II using all high energy data recorded by the H1 experiment. This corresponds to a total integrated luminosity of 337 pb$^{-1}$. All event topologies involving isolated electrons, photons, muons, neutrinos and jets with high tra

Peter Bickel, Bas Kleijn, John Rice

This paper treats the problem of detecting periodicity in a sequence of photon arrival times, which occurs, for example, in attempting to detect gamma-ray pulsars. A particular focus is on how auxiliary information, typically source intensity, background intensity, and incidence angles and energies associated with each photon arrival should be used to maximi

Gianni Franceschini, S. Muthukrishnan, Mihai Patrascu

It is well known that n integers in the range [1,n^c] can be sorted in O(n) time in the RAM model using radix sorting. More generally, integers in any range [1,U] can be sorted in O(n sqrt{loglog n}) time. However, these algorithms use O(n) words of extra memory. Is this necessary? We present a simple, stable, integer sorting algorithm for words of size O(lo

Benny Sudakov

For two graph H and G, the Ramsey number r(H, G) is the smallest positive integer n such that every red-blue edge coloring of the complete graph K_n on n vertices contains either a red copy of H or a blue copy of G. Motivated by questions of Erdos and Harary, in this note we study how the Ramsey number r(K_s, G) depends on the size of the graph G. For s \geq

Benny Sudakov

We show that every K_4-free graph G with n vertices can be made bipartite by deleting at most n^2/9 edges. Moreover, the only extremal graph which requires deletion of that many edges is a complete 3-partite graph with parts of size n/3. This proves an old conjecture of P. Erdos.

Noga Alon, Michael Krivelevich, Benny Sudakov

We derive a sufficient condition for a sparse graph G on n vertices to contain a copy of a tree T of maximum degree at most d on (1-ε)n vertices, in terms of the expansion properties of G. As a result we show that for fixed d\geq 2 and 0<ε<1, there exists a constant c=c(d,ε) such that a random graph G(n,c/n) contains almost surely a copy of every tree T on (

Noga Alon, Benny Sudakov

Let G be a graph on n vertices in which every induced subgraph on s=\log^3 n vertices has an independent set of size at least t=\log n. What is the largest q=q(n) so that every such G must contain an independent set of size at least q ? This is one of several related questions raised by Erdos and Hajnal. We show that q(n)=Θ(\log^2 n/\log \log n), investigate

Lucilia Borsari, Fernanda Cardona, Peter Wong

A classical theorem of H. Hopf asserts that a closed connected smooth manifold admits a nowhere vanishing vector field if and only if its Euler characteristic is zero. R. Brown generalized Hopf&#39;s result to topological manifolds, replacing vector fields with path fields. In this note, we give an equivariant analog of Brown&#39;s theorem for locally smooth

Ilya Kapovich, Paul Schupp

Motivated by results on generic-case complexity in group theory, we apply the ideas of effective Baire category and effective measure theory to study complexity classes of functions which are &#34;fractionally computable&#34; by a partial algorithm. For this purpose it is crucial to specify an allowable effective density, $δ$, of convergence for a partial al

Brian Siana, Harry I. Teplitz, James Colbert, Henry C. Ferguson

We examine deep far-ultraviolet (1600 Angstrom) imaging of the Hubble Deep Field-North (HDFN) and the Hubble Ultra Deep Field (HUDF) to search for leaking Lyman continuum radiation from starburst galaxies at z~1.3. There are 21 (primarily sub-L*) galaxies with spectroscopic redshifts between 1.1<z<1.5 and none are detected in the far-UV. We fit stellar popul

Ricardo E. Avila

The release of a gas limited by surface desorption, or by diffusion from the bulk of spherical pebbles is revisited. A method is proposed to identify the release limiting process, by comparing a partial temperature ramp, up to slightly beyond the release peak, followed by a rapid temperature drop, to a second, full release ramp. Comparing the release curve f

Naveen A. Reddy, Charles C. Steidel, Max Pettini, Kurt L. Adelberger

We use a sample of rest-frame UV selected and spectroscopically observed galaxies at redshifts 1.9<z<3.4, combined with ground-based spectroscopic H-alpha and Spitzer MIPS 24 micron data, to derive the most robust measurements of the rest-frame UV, H-alpha, and infrared (IR) luminosity functions (LFs) at these redshifts. Our sample is by far the largest of i

Michael C. Cooper, Jeffrey A. Newman, Benjamin J. Weiner, Renbin Yan

Using galaxy samples drawn from the Sloan Digital Sky Survey and the DEEP2 Galaxy Redshift Survey, we study the relationship between star formation and environment at z ~ 0.1 and z ~ 1. We estimate the total star-formation rate (SFR) and specific star-formation rate (sSFR) for each galaxy according to the measured [O II] nebular line luminosity, corrected us

S. V. Ter-Antonyan

The problem of the uniqueness of solutions during the evaluation of primary energy spectra in the knee region using an extensive air shower (EAS) data set and the EAS inverse approach is investigated. It is shown that the unfolding of primary energy spectra in the knee region leads to mutually compensative pseudo solutions. These solutions may be the reason

Y. Alhassid, G. F. Bertsch, L. Fang

We apply the configuration-interaction method to calculate the spectra of two-component Fermi systems in a harmonic trap, studying the convergence of the method at the unitary interaction limit. We find that for a fixed regularization of the two-body interaction the convergence is exponential or better in the truncation parameter of the many-body space. Howe

J. E. S. Costa, E. Michel, J. Pena, O. Creevey

The eclipsing delta-Scuti star HD 172189 is a probable member of the open cluster IC 4756 and a promising candidate target for the CoRoT mission. The detection of pulsation modes is the first step in the asteroseismological study of the star. Further, the calculation of the orbital parameters of the binary system allows us to make a dynamical determination o

Jon Wilkening

We derive estimates of the Babuuska-Brezzi inf-sup constant $β$ for two-dimensional incompressible flow in a periodic channel with one flat boundary and the other given by a periodic, Lipschitz continuous function $h$. If $h$ is a constant function (so the domain is rectangular), we show that periodicity in one direction but not the other leads to an interes

Jon F. Carlson, Jacques Thevenaz

This paper is a major step in the classification of endotrivial modules over p-groups. Let G be a finite p-group and k be a field of characteristic p. A kG-module M is an endo-trivial module if {\End_k(M)\cong k\oplus F} as kG-modules, where F is a free module. The classification of endo-trivial modules is the crucial step for understanding the more general

Paola Testa, Jeremy J. Drake, Giovanni Peres, David P. Huenemoerder

We have investigated the optical thickness of the coronal plasma through the analysis of high-resolution X-ray spectra of a large sample of active stars observed with the High Energy Transmission Grating Spectrometer on Chandra. In particular, we probed for the presence of significant resonant scattering in the strong Lyman series lines arising from hydrogen

Evelina Shamarova

A generalized version of Chernoff&#39;s theorem has been obtained. Namely, the version of Chernoff&#39;s theorem for semigroups obtained in a paper by Smolyanov, Weizsaecker, and Wittich is generalized for a time-inhomogeneous case. The main theorem obtained in the current paper, Chernoff&#39;s theorem for evolution families, deals with a family of time-depe

Pawel Wegrzyn

For one-dimensional vibrating cavity systems appearing in the standard illustration of the dynamical Casimir effect, we propose an approach to the construction of exact closed-form solutions. As new results, we obtain solutions that are given for arbitrary frequencies, amplitudes and time regions. In a broad range of parameters, a vibrating cavity model exhi

W. A. Bryan, E. M. L. English, J. McKenna, J. Wood

A coherent superposition of rotational states in D$_2$ has been excited by nonresonant ultrafast (12 femtosecond) intense (2 $\times$ 10$^{14}$ Wcm$^{-2}$) 800 nm laser pulses leading to impulsive dynamic alignment. Field-free evolution of this rotational wavepacket has been mapped to high temporal resolution by a time-delayed pulse, initiating rapid double

A. Sparavigna

The paper studies the modes of vibrations of a lattice with rod-like particles, in a continuum model where the sites of the lattice are the connections among strings and rigid rods. In these structures then, translational and rotational degrees of freedom are strongly coupled. We will discuss in particular two-dimensional lattices with auxetic-like behaviour

S. Grossmann, M. Robnik

We study the level spacing distribution $P(S)$ of 2D real random matrices both symmetric as well as general, non-symmetric. In the general case we restrict ourselves to Gaussian distributed matrix elements, but different widths of the various matrix elements are admitted. The following results are obtained: An explicit exact formula for $P(S)$ is derived and

James Lepowsky

In this exposition, I discuss several developments in the theory of vertex operator algebras, and I include motivation for the definition.

A. D. Chernin, I. D. Karachentsev, P. Teerikorpi, M. J. Valtonen

We report the detection of dark energy near the Milky Way made with precision observations of the local Hubble flow of expansion. We estimate the local density of dark energy and find that it is near, if not exactly equal to, the global dark energy density. The result is independent of, compatible with, and complementary to the horizon-scale observations in

Indranil Chakrabarty

It is a well known fact that an quantum state $|ψ(θ,ϕ)>$ is represented by a point on the Bloch sphere, characterized by two parameters $θ$ and $ϕ$. In a recent work we already proved that it is impossible to partially swap these quantum parameters. Here in this work we will show that this impossibility theorem is consistent with principles like unitarity of

Yu. M. Sinyukov, S. V. Akkelin, Iu. A. Karpenko

We describe RHIC pion data in central A+A collisions and make predictions for LHC based on hydro-kinetic model, describing continuous 4D particle emission, and initial conditions taken from Color Glass Condensate (CGC) model.

A. Campillo, F. Delgado, S. M. Gusein-Zade

In previous papers, there were computed the Poincare series of some (multi-index) filtrations on the ring of germs of functions on a rational surface singularity. These Poincare series were written as the integer parts of certain fractional power series, an interpretation of whom was not given. Here we show that, up to a simple change of variables, these fra

Manuel Blickle

In this note we show that finitely generated unit $O_X[σ]$--modules for $X$ regular and $F$--finite have a minimal root (in the sense of [Lyubeznik, F-modules] Definition~3.6). This problem was posed by Lyubeznik and answered by himself in the case that $X=\Spec R$ is a complete local ring. One immediate consequence of this result is that the parameter test

Peter Klimek, Renaud Lambiotte, Stefan Thurner

We introduce a statistical physics model for opinion dynamics on random networks where agents adopt the opinion held by the majority of their direct neighbors only if the fraction of these neighbors exceeds a certain threshold, p_u. We find a transition from total final consensus to a mixed phase where opinions coexist amongst the agents. The relevant parame

Piotr T. Chruściel, Paul Tod

We prove an inequality relating the trace of the extrinsic curvature, the total angular momentum, the centre of mass, and the Trautman-Bondi mass for a class of gravitational initial data sets with constant mean curvature extending to null infinity. As an application we obtain non-existence results for the asymptotic Dirichlet problem for CMC hypersurfaces i

M. Ya. Amusia, A. S. Baltenkov, L. V. Chernysheva

We demonstrate rather interesting manifestations of co-existence of resonance features in characteristics of the photoionization of 3d-electrons in Xe, Cs and Ba endohedral atoms. It is shown that for all of the considered atoms the reflection by the fullerene shell of photoelectrons produced by the 3d subshell photoionization affects greatly partial photoio

J. Colliander, A. D. Ionescu, C. E. Kenig, G. Staffilani

In this paper we establish local well-posedness of the KP-I problem, with initial data small in the intersection of the natural energy space with the space of functions which are square integrable when multiplied by the weight y. The result is proved by the contraction mapping principle. A similar (but slightly weaker) result was the main Theorem in the pape

C. P. Martin, C. Tamarit

We consider noncommutative gauge theory defined by means of Seiberg-Witten maps for an arbitrary semisimple gauge group. We compute the one-loop UV divergent matter contributions to the gauge field effective action to all orders in the noncommutative parameters $θ$. We do this for Dirac fermions and complex scalars carrying arbitrary representations of the g

A. Yu. Dubin

For a generic gauge-invariant correlator <{\cal Q}[A_μ]>_{A}, we reformulate the standard D=4 Yang-Mills theory as a renormalizable system of two interacting fields a_μ and B_μ which faithfully represent high- and low-energy degrees of freedom of the single gauge field A_μ in the original formulation. It opens a possibility to synthesize an infrared-nonsingu

Jean-Luc Garden, Jacques Richard, H. Guillou, O. Bourgeois

Polytetrafluoroethylene can be considered as a model for calorimetric studies of complex systems with thermodynamics transitions at ambient temperature. This polymer exhibits two phase transitions of different nature at 292 K and 303 K. We show that sensitive ac-calorimetry measurements allow us to study the thermodynamic behaviour of polytetrafluoroethylene

Michael S. Noble

We introduce SLIRP, a module generator for the S-Lang numerical scripting language, with a focus on its vectorization capabilities. We demonstrate how both SLIRP and S-Lang were easily adapted to exploit the inherent parallelism of high-level mathematical languages with OpenMP, allowing general users to employ tightly-coupled multiprocessors in scriptable re

Jean-Luc Garden

This paper gives a simple derivation of the well-known expression of the frequency dependent complex heat capacity in modulated temperature experiments. It aims at clarified again that the generalized calorimetric susceptibility is only due to the non-equilibrium behaviour occurring in the vicinity of thermodynamic equilibrium of slow internal degrees of fre

Mihai Mihailescu, Vicentiu Radulescu

We study the boundary value problem $-{\rm div}((|\nabla u|^{p_1(x)-2}+|\nabla u|^{p_2(x)-2})\nabla u)=λ|u|^{q(x)-2}u$ in $Ω$, $u=0$ on $\partialΩ$, where $Ω$ is a bounded domain in $\RR^N$ with smooth boundary, $λ$ is a positive real number, and the continuous functions $p_1$, $p_2$, and $q$ satisfy $1<p_2(x)<q(x)<p_1(x)<N$ and $\max_{y\in\barΩ}q(y)<\frac{N

Lutz Schröder, Dirk Pattinson

For lack of general algorithmic methods that apply to wide classes of logics, establishing a complexity bound for a given modal logic is often a laborious task. The present work is a step towards a general theory of the complexity of modal logics. Our main result is that all rank-1 logics enjoy a shallow model property and thus are, under mild assumptions on

Mark D. Roberts

Palatini variation of Jordan frame lagrangians gives an equation relating the dilaton to the object of non-metricity and hence the existence of the dilaton implies that the spacetime connection is more general than that given soley by the Christoffel symbol of general relativity. Transferring from Jordan to Einstein frame, which connection, lagrangian, field

George A. Levin, Paul N. Barnes

We consider the distribution of an electric field in YBCO-coated conductors for a situation in which the DC transport current is forced into the copper stabilizer due to a weak link -- a section of the superconducting film with a critical current less than the transport current. The electric field in the metal substrate is also discussed. The results are com

E. Muller, Q. Parker

We present here a preliminary report and commentary of recently processed observations of Ha emission towards the Magellanic Bridge. These data have been analysed in an attempt to quantify the extent to which the stellar population is capable of reshaping the local ISM. We find that the Ha emission regions are small, weak and sparsely distributed, consistent

T. A. A. Sigut, C. E. Jones

We have computed radiative equilibrium models for the gas in the circumstellar envelope surrounding the hot, classical Be star $γ$Cassiopeia. This calculation is performed using a code that incorporates a number of improvements over previous treatments of the disk&#39;s thermal structure by \citet{mil98} and \citet{jon04}; most importantly, heating and cooli

Sapon Tanachaiwiwat, Ahmed Helmy

Encounter-based network is a frequently-disconnected wireless ad-hoc network requiring immediate neighbors to store and forward aggregated data for information disseminations. Using traditional approaches such as gateways or firewalls for deterring worm propagation in encounter-based networks is inappropriate. We propose the worm interaction approach that re

Jozsef Cserti, Andras Palyi, Csaba Peterfalvi

We show that the wavefunctions form caustics in circular graphene p-n junctions which in the framework of geometrical optics can be interpreted with negative refractive index.

Michael A. Ivanov

Small effects of quantum gravity on the scale $\sim 10^{-3} eV$ and their cosmological consequences are discussed and compared with observations of supernovae 1a, gamma-ray bursts and galaxies.

Victor Novikov

We propose a new mechanism for a &#39;&#39;small&#34; violation of Pauli Principle in the framework of Quantum Field Theory. Instead of modification of algebra - commutation relations for fields - we introduce spontaneous violation of Pauli Principle which is proportional to the vacuum fermionic condensate.

F. Nesi, M. Grifoni, E. Paladino

We study the dynamics of a symmetric two-level system strongly coupled to a broadened harmonic mode. Upon mapping the problem onto a spin-boson model with peaked spectral density, we show how analytic solutions can be obtained, at arbitrary detuning and finite temperatures, in the case of large Q-factors of the oscillator. In general {\em two} or more oscill

S. A. Khan, D. V. Shulyak

Context. See abstract in the paper. Aims. See abstract in the paper. Methods. See abstract in the paper. Results. We present a homogeneous study of model atmosphere temperature structure, energy distribution, photometric indices in the uvbybeta and Delta_a systems, hydrogen line profiles, and the abundance determination procedure as it applies to CP stars. I

D. Ceresoli, T. Zykova-Timan, U. Tartaglino, E. Tosatti

Alkali halide (100) crystal surfaces are poorly wetted by their own melt at the triple point. We carried out simulations for NaCl(100) within the well tested BMHFT model potential. Calculations of the solid-vapor, solid-liquid and liquid-vapor free energies showed that solid NaCl(100) is a non-melting surface, and explain its bad wetting in detail. The extre

J. H. Debes, S. Sigurdsson, B. Hansen

Hydrogen atmosphere white dwarfs with metal lines, so-called DAZs, require external accretion of material to explain the presence of weak metal line absorption in their photospheres. The source of this material is currently unknown, but could come from the interstellar medium, unseen companions, or relic planetesimals from asteroid belt or Kuiper belt analog

V. Baru, J. Haidenbauer, C. Hanhart, A. Kudryavtsev

We investigate the role of the delta isobar in the reaction $πd\to πd$ at threshold in chiral effective field theory. We discuss the corresponding power counting and argue that this calculation completes the evaluation of diagrams up to the order (m_pi/M_N)^(3/2), with m_pi (M_N) for the pion (nucleon) mass. The net effect of all delta contributions at this

Delphine Porquet, Phil Uttley, James N. Reeves, Alex Markowitz

(Abridged) We present here a long (100ks) XMM-Newton follow-up of the Seyfert 1.8 galaxy ESO113-G010 performed in November 2005, in order to study over a longer time-scale its main X-ray properties. The source was found in a higher/softer time-averaged flux state, and timing analysis of this source reveals strong, rapid variability. The Power Spectral Densit

J. Dunning-Davies

The mathematical properties associated with the widely accepted concept of the extensivity of many of the common thermodynamic variables are examined and some of their consequences considered. The possible conflict between some of these and currently accepted results of special relativistic thermodynamics is highlighted. Although several questions are raised

C. J. Bomhof, P. J. Mulders

We argue that through the Wilson lines, gauge invariance has as an effect that the hard functions in weighted spin-asymmetries in hadronic scattering processes are given by gluonic pole cross sections, rather than the usual partonic cross sections.

Mauro R. Cosentino

Heavy Quarkonium states modifications in relativistic heavy ion collisions have been of great interest since the proposal by Matsui and Satz of J/psi suppression as a signature of Quark-Gluon Plasma (QGP) formation. Recent studies suggest that the excited states chi_c, psi(2S) and Upsilon(3S) melt sequentially[1,2] and the amount of observed suppression depe

Christian Boulinier, Franck Petit

We introduce a simple tool called the wavelet (or, r-wavelet) scheme. Wavelets deals with coordination among processes which are at most r hops away of each other. We present a selfstabilizing solution for this scheme. Our solution requires no underlying structure and works in arbritrary anonymous networks, i.e., no process identifier is required. Moreover,

R. P. Kraft, W. R. Forman, M. J. Hardcastle, C. Jones

We present results from a {\em Chandra} observation of the cluster gas associated with the FR II radio galaxy 3C 438. This radio galaxy is embedded within a massive cluster with gas temperature $\sim$17 keV and bolometric luminosity of 6$\times10^{45}$ ergs s$^{-1}$. It is unclear if this high temperature represents the gravitational mass of the cluster, or

R. P. Kraft, P. E. J. Nulsen, M. Birkinshaw, D. M. Worrall

We present results from deeper {\em Chandra} observations of the southwest radio lobe of Centaurus A, first described by Kraft et al. (2003). We find that the sharp X-ray surface brightness discontinuity extends around $\sim$75% of the periphery of the radio lobe, and detect significant temperature jumps in the brightest regions of this discontinuity nearest

Clovis Maia, Ralf Schützhold

We propose a simple quantum field theoretical toy model for black hole evaporation and study the back-reaction of Hawking radiation onto the classical background. It turns out that the horizon is also ``pushed back&#39;&#39; in this situation (i.e., the interior region shrinks) but this back-reaction is not caused by energy conservation but by momentum balan

Ingemar Eriksson

In a previous paper we showed that the electromagnetic superenergy tensor, the Chevreton tensor, gives rise to a conserved current when there is a hypersurface orthogonal Killing vector present. In addition, the current is proportional to the Killing vector. The aim of this paper is to extend this result to the case when we have a two-parameter Abelian isome

Émilien Azema, F. RadjaÏ, R. Peyroux, G. Saussine

We perform a detailed analysis of the contact force network in a dense confined packing of pentagonal particles simulated by means of the contact dynamics method. The effect of particle shape is evidenced by comparing the data from pentagon packing and from a packing with identical characteristics except for the circular shape of the particles. A counterintu

Dennis D. Dietrich, Gerald V. Dunne

We propose a new application of the Gutzwiller trace formula formalism, to give a compact expression for the semiclassical vacuum pair production rate in quantum electrodynamics, for general inhomogeneous electromagnetic background fields.

Andrei Goncharov, Olivier Lopez, Anne Amy, Frédéric Du Burck

The absolute frequencies of the hyperfine components of the R(26) 62-0 transition in molecular iodine at 501.7 nm are measured for the first time with an optical clockwork based on a femtosecond laser frequency comb generator. The set-up is composed of an Ar+ laser locked to a hyperfine component of the R(26) 62-0 transition detected in a continuously pumped

Ahmed Ait Ali, Fabien Michaut, Francis Lepage

In recent years, there has been a strong interest in measuring the available bandwidth of network paths. Several methods and techniques have been proposed and various measurement tools have been developed and evaluated. However, there have been few comparative studies with regards to the actual performance of these tools. This paper presents a study of avail

Miles Simon

In this paper we prove local results for solutions to the Ricci flow (heat flow) whose speed (height) is bounded by $\frac c t$ for some time interval $ t \in (0,T)$. These results are contained in chapter 7 of the author&#39;s habilitation thesis, University of Freiburg, Germany, 2006.

Hideaki Maebashi, Yasutami Takada

With paying special attention to the divergence in the compressibility $κ$, we study the Coulombic screening in alkali metals to find singular long-range fluctuations in the electronic polarization originating from this divergence. As a consequence of this singularity, we predict the decrease of the equilibration distance between ions against the increase of

Misha Kozlov, Arif I. Shoshi, Bo-Wen Xiao

We discuss a new physical phenomenon for R_pA in the fixed coupling case, the total gluon shadowing, which arises due to the effect of gluon number fluctuations.

M. Sindel, L. Borda, J. Martinek, R. Bulla

We systematically study the influence of ferromagnetic leads on the Kondo resonance in a quantum dot tuned to the local moment regime. We employ Wilson&#39;s numerical renormalization group method, extended to handle leads with a spin asymmetric density of states, to identify the effects of (i) a finite spin polarization in the leads (at the Fermi-surface),

G. Barontini, M. Modugno

We investigate the stability of an attractive Bose-Einstein condensate in a moving 1D optical lattice in the presence of transverse confinement. By means of a Bogoliubov linear stability analysis we find that the system is dynamically unstable for low quasimomenta and becomes stable near the band edge, in a specular fashion with respect to the repulsive case

Itzhack Dana, Vladislav Roitberg

Quantum resonance (QR) is defined in the free-falling frame of the quantum kicked particle subjected to gravity. The general QR conditions are derived. They imply the rationality of the gravity parameter $η$, the kicking-period parameter $τ/(2π)$, and the quasimomentum $β$. Exact results are obtained concerning wave-packet evolution for arbitrary periodic ki

Riccardo Argurio, Cyril Closset

We study the quantum corrections to the moduli space of the quiver gauge theory corresponding to regular and fractional D3-branes at the dP_1 singularity. We find that besides the known runaway behavior at the lowest step of the duality cascade, there is a runaway direction along a mesonic branch at every higher step of the cascade. Moreover, the algebra of

Jan Harm van der Walt

By setting up appropriate uniform convergence structures, we are able to reformulate the Order Completion Method of Oberguggenberger and Rosinger in a setting that more closely resembles the usual topological constructions for solving PDEs. As an application, we obtain existence and uniqueness results for the solutions of arbitrary continuous, nonlinear PDEs

S. Antoci, D. -E. Liebscher

In the year 1957, when interest in Einstein&#39;s unified field theory was fading away for lack of understanding of its physical content, Treder performed a momentous critical analysis of the possible definitions of the electric four-current in the theory. As an outcome of this scrutiny he was able to prove by the E.I.H. method that properly defined point ch

S. B. Fadeev, V. D. Ivashchuk

A 5-dimensional cosmological solution in the model with two 2-forms and two ``phantom&#39;&#39; scalar fields is considered. The model contains two dilatonic coupling vectors obeying certain restrictions. It is shown that there exists a time interval where accelerating expansion of ``our&#39;&#39; 3-dimensional space is compatible with a small value of effec

Massimo Mannarelli, Cristina Manuel

We discuss the properties of a system composed by a static plasma traversed by a jet of particles. Assuming that both the jet and the plasma can be described using a hydrodynamical approach, and in the conformal limit, we find that unstable modes arise when the velocity of the jet is larger than the speed of the sound of the plasma and only modes with moment

Khosrow Chadan

Using the integral representations of the solutions of Schrödinger equation, which are the essential ingredients of the Gel&#39;fand-Levitan and Marchenko integral equations of inverse scattering theory, we obtain a general theorem on the positivity of some integral transforms, and extend the theorem of Bochner on Fourier transforms of functions of positive

D. Stauffer

I review three socio-economic models of economic opinions, urban segregation, and language change and show that the well known two-dimensional Ising model gives about the same results in each case.

Giovanni Forni

We survey recent progress on the Greenfield-Wallach and Katok conjectures on globally hypoelliptic and cohomology free vector fields and derive a proof of the conjectures in dimension three. The argument is primarily based on recent work of F. and J. Rodriguez Hertz which allows us to reduce the question to the case of a Reeb flow for a contact form. The con

B. O. Kerbikov

The quark fluctuation propagator is evaluated. It defines the diffusion coefficient in the vicinity of the phase transition and the gradient term in the Ginzburg-Landau functional.