May 2005 arXiv papers — page 14

G. Borges

We present the final results of experiment NA50 on charmonia production in Pb-Pb interactions at 158 A GeV. A strong increasing suppression is observed with increasing centrality, for both the jpsi and psiprime resonances. We also present new developments regarding the jpsi and psiprime normal nuclear absorption determinations deduced from proton-nucleus dat

Chris Hays

The W boson mass (mW) is a key parameter of the standard model, constraining the mass of the unobserved Higgs boson. Using Tevatron ppbar collision data from 1992-1996, the CDF and D0 collaborations measured mW to a precision of 59 MeV. The ongoing Tevatron Run 2 has produced a factor of 5 more collisions, promising a significant reduction in the W mass unce

N. Pinto-Neto, E. Sergio Santini, F. T. Falciano

The causal interpretation of quantum mechanics is applied to a homogeneous and isotropic quantum universe, whose matter content is composed by non interacting dust and radiation. For wave functions which are eigenstates of the total dust mass operator, we find some bouncing quantum universes which reachs the classical limit for scale factors much larger than

S. Mukherjee, B. C. Paul, S. D. Maharaj, A. Beesham

We present an emergent universe scenario making use of a new solution of the Starobinsky model. The solution belongs to a one parameter family of solutions, where the parameter is determined by the number and the species (spin-values) of primordial fields. The general features of the model have also been studied.

A. Ashoorioon, R. B. Mann

Anisotropy of the cosmic microwave background radiation (CMB) originates from both tensor and scalar perturbations. To study the characteristics of each of these two kinds of perturbations, one has to determine the contribution of each to the anisotropy of CMB. For example, the ratio of the power spectra of tensor/scalar perturbations can be used to tighten

Morad Amarzguioui, Oyvind Gron

We look at a gas of dust and investigate how its entropy evolves with time under a spherically symmetric gravitational collapse. We treat the problem perturbatively and find that the classical thermodynamic entropy does actually increase to first order when one allows for gravitational potential energy to be transferred to thermal energy during the collapse.

Jaime Gomez, Ignacio Melgar, Juan Seijas

This paper presents a short evaluation about the integration of information derived from wavelet non-linear-time-invariant (non-LTI) projection properties using Support Vector Machines (SVM). These properties may give additional information for a classifier trying to detect known patterns hidden by noise. In the experiments we present a simple electromagneti

Jaime Gomez, Ignacio Melgar, Juan Seijas

Current approaches in pulse detection use domain transformations so as to concentrate frequency related information that can be distinguishable from noise. In real cases we do not know when the pulse will begin, so we need a time search process in which time windows are scheduled and analysed. Each window can contain the pulsed signal (either complete or inc

Jaime Gomez, Ignacio Melgar, Juan Seijas, Diego Andina

The problem of known signal detection in Additive White Gaussian Noise is considered. In previous work, a new detection scheme was introduced by the authors, and it was demonstrated that optimum performance cannot be reached in a real implementation. In this paper we analyse Support Vector Machines (SVM) as an alternative, evaluating the results in terms of

Oscar Sotolongo-Costa, Alejandro Gonzalez Gonzalez, Francois Brouers

We find the value of constants related to constraints in characterization of some known statistical distributions and then we proceed to use the idea behind maximum entropy principle to derive generalized version of this distributions using the Tsallis' and Renyi information measures instead of the well-known Bolztmann-Gibbs-Shannon. These generalized di

Aurel Bulgac

A comment on the letter by M. Machida and T. Koyama, Phys. Rev. Lett. {\bf 94}, 140401 (2005) and also on the preprint by Y. Kawaguchi and T. Ohmi, cond-mat/0411018.

J. A. Yasi, G. Korniss, T. Caraco

We study a discrete spatial model for invasive allele spread in which two alleles compete preemptively, initially only the "residents" (weaker competitors) being present. We find that the spread of the advantageous mutation is well described by homogeneous nucleation; in particular, in large systems the time-dependent global density of the resident a

Eduardo M. M. Santos, Alba Theumann

We analyze the infinite range Ising spin-glass in a transverse-field below the critical temperature by a one step replica symmetry theory(1S-RSB). The set of n replicas is divided in r blocks of m replicas each. We present results for different values of the block-size parameter m. The spin operators are represented by bilinear combinations of fermionic fiel

M. Shayegan

This paper provides a review of developments in the physics of two-dimensional electron systems in perpendicular magnetic fields.

S. Tewari, D. Belitz, T. R. Kirkpatrick

It is shown that a condensation transition involving a chiral order parameter can occur in itinerant helimagnets, in analogy to the transition between the isotropic phase and the phase known as blue fog or blue phase III in cholesteric liquid crystals. It is proposed that such a transition is the explanation for recent neutron scattering results in MnSi. Pre

A. Bhattacharyay

We argue that the lower bound to the barrier energy to flip an up/down spin domain embedded in a down/up spin environment for Ising spin glass is independent of the size of the system. The argument shows the existence of at least one dynamical way through which it is possible to bypass local maxima in the phase space. For an arbitrary case where one flips an

Susumu Takahashi, Stephen Hill

The cavity perturbation technique is an extremely powerful method for measuring the electrodynamic response of a material in the millimeter- and sub-millimeter spectral range (10 GHz to 1 THz), particularly in the case of high-field/frequency magnetic resonance spectroscopy. However, the application of such techniques within the limited space of a high-field

V. S. -W. Chung, P. Samuelsson, M. Buttiker

We investigate the visibility of the current and shot-noise correlations of electrical analogs of the optical Mach-Zehnder interferometer and the Hanbury Brown Twiss interferometer. The electrical analogs are discussed in conductors subject to high magnetic fields where electron motion is along edge states. The transport quantities are modulated with the hel

E. L. Ivchenko, A. N. Poddubny

We have developed a theory of exciton-polariton band structure of resonant three-dimensional photonic crystals for arbitrary dielectric contrast and effective mass of the exciton that is excited in one of the compositional materials. The calculation has been carried out for a periodic array of spheres embedded in a dielectric matrix. It has been shown that t

Alexey Nikulov

Connection between an intrinsic breach of symmetry of equilibrium motion and violation of the second law is accentuated. An intrinsic breach only of clockwise - counter-clockwise symmetry of a circular equilibrium motion can be logical under equilibrium conditions, whereas a breach of right-left symmetry should be always an actual violation of the second law

R. García-Rojo, F. Alonso-Marroquín, H. J. Herrmann

The existence of a very special ratcheting regime has recently been reported in a granular packing subjected to cyclic loading \cite{alonso04}. In this state, the system accumulates a small permanent deformation after each cycle. After a short transient regime, the value of this permanent strain accumulation becomes independent on the number of cycles. We sh

H. Tototzintle-Huitle, R. Baquero

We use the Surface Green Function Matching (SGFM) method and a tight-binding hamiltonian to calculate the (100)-surface electronic band structure and local density of states of the series of Cu-based A^{I}B^{III}C2^{VI} chalcopyrites . We find four surface states in the optical gap energy region of s-p character and three surface states in the conduction ban

Jones T. K. Wan, Ophelia K. C. Tsui, Hoi-Sing Kwok, Ping Sheng

We consider the pretilt alignment of nematic liquid crystal (LC) on inhomogeneous surface patterns comprising patches of homeotropic or homogeneous alignment domains, with azimuthal anisotropy assumed in the surface plane. We found that the resultant LC pretilt generally increases continuously from the homogeneous limit to the homeotropic limit as the area f

E. Z. Meilikhov, R. M. Farzetdinova

For Small World Ising systems of different dimensions, "concentration" dependencies T_C(p) of the Curie temperature upon the fraction p of long-range links have been derived on a basis of simple physical considerations. We have found T_C(p) ~ 1/ln|p| for 1D, T_C(p) ~ p^{1/2} for 2D, and T_C(p) ~ p^{2/3} for 3D.

P. G. Kevrekidis, A. Stefanov, D. E. Pelinovsky

In the present short communication, we revisit nonlinearity management of the time-periodic nonlinear Schrodinger equation and the related averaging procedure. We prove that the averaged nonlinear Schrodinger equation does not support the blow-up of solutions in higher dimensions, independently of the strength in the nonlinearity coefficient variance. This c

M. Oestreich, M. Roemer, R. J. Haug, D. Haegele

We observe the noise spectrum of electron spins in bulk GaAs by Faraday rotation noise spectroscopy. The experimental technique enables the undisturbed measurement of the electron spin dynamics in semiconductors. We measure exemplarily the electron spin relaxation time and the electron Lande g-factor in n-doped GaAs at low temperatures and find good agreemen

Henri Saarikoski, Ari Harju

We study electronic structures of quasi-two-dimensional finite electron systems in high magnetic fields. The solutions in the fractional quantum Hall regime are interpreted as quantum liquids of electrons and off-electron vortices. The ground states are classified according to the number of vortices inside the electron droplet. The theory predicts observable

Balázs Kozma, Matthew B. Hastings, G. Korniss

We consider diffusion processes on power-law small-world networks in different dimensions. In one dimension, we find a rich phase diagram, with different transient and recurrent phases, including a critical line with continuously varying exponents. The results were obtained using self-consistent perturbation theory and can also be understood in terms of a sc

T. Gaber, E. Goldobin, A. Sterck, R. Kleiner

We investigate the creation of an arbitrary $κ$-discontinuity of the Josephson phase in a long Nb-AlO_x-Nb Josephson junction (LJJ) using a pair of tiny current injectors, and study the formation of fractional vortices formed at this discontinuity. The current I_inj, flowing from one injector to the other, creates a phase discontinuity kappa ~ I_inj. The cal

Gerard Ben Arous, Jiri Cerny

Let E_i be a collection of i.i.d. exponential random variables. Bouchaud's model on Z is a Markov chain X(t) whose transition rates are given by w_{ij}=ν\exp(-β((1-a)E_i-aE_j)) if i, j are neighbors in Z. We study the behavior of two correlation functions: P[X(t_w+t)=X(t_w)] and P[X(t')=X(t_w) \forall t'\in[t_w,t_w+t]]. We prove the (sub)aging be

Kenneth J. Mighell

The key features of the MATPHOT algorithm for precise and accurate stellar photometry and astrometry using discrete Point Spread Functions are described. A discrete Point Spread Function (PSF) is a sampled version of a continuous PSF which describes the two-dimensional probability distribution of photons from a point source (star) just above the detector. Th

Thomas H. Puzia, Markus Kissler-Patig, Daniel Thomas, Claudia Maraston

An analysis of ages, metallicities, and [alpha/Fe] ratios of globular cluster systems in early-type galaxies is presented, based on Lick index measurements summarized in Puzia et al. (2004, Paper I of this series). In the light of calibration and measurement uncertainties, age-metallicity degeneracy, and the relative dynamic range of Lick indices, as well as

V. P. Goranskij, S. Yu. Shugarov, P. Kroll, A. Golovin

The discovery of an Algol type eclipsing variable star having highly elliptical orbit with the period of 11.628 day is reported.

Thomas H. Puzia, Markus Kissler-Patig, Daniel Thomas, Claudia Maraston

We present Lick line-index measurements of extragalactic globular clusters in seven early-type galaxies (NGC 1380, 2434, 3115, 3379, 3585, 5846, and 7192) with different morphological types (E-S0) located in field and group/cluster environments. High-quality spectra were taken with the FORS2 instrument at ESO's Very Large Telescope. About 50% of our data

Ken Pounds

Broad band X-ray spectra of high statistical quality obtained with the EPIC instruments on XMM-Newton are being used to address key issues in AGN Physics, including the evidence for strong gravity, massive and energetic outflows and the effects of reflection and absorption in cold dense matter. A progress report on these topics is presented by reference to h

Sabine Mengel, Matthew D. Lehnert, Niranjan Thatte, Reinhard Genzel

Accurately determining the star formation history in NGC 4038/4039 -- ``The Antennae'' is hampered by extinction. We therefore used near infrared images obtained with ISAAC at the VLT and with SOFI at the NTT to determine the recent star formation history in this merger. In combination with archival HST data, we determined ages, extinction and other

J. K. Kotilainen, T. Hyvonen, R. Falomo

(abridged) We present near-infrared Ks-band imaging of 13 high redshift (0.6 < z < 1.3) BL Lac objects. We clearly detect the host in eight objects, and marginally in three others. In all cases, the host galaxy is well represented by an r^1/4 surface brightness law. The host galaxies of high redshift BL Lacs are large (<R(e)> ~7 kpc) and very luminous (<M(K)

D. Ardouin, A. Belletoile, D. Charrier, R. Dallier

Studies of the radio detection of Extensive Air Showers is the goal of the demonstrative experiment CODALEMA. Previous analysis have demonstrated that detection around $5.10^{16}$ eV was achieved with this set-up. New results allow for the first time to study the topology of the electric field associated to EAS events on a event by event basis.

J. Hatchell, M. K. Bird, F. F. S. van der Tak, W. A. Sherwood

Radio observations in the ammonia inversion lines of four comets, C/2001 A2 (LINEAR), 153P/Ikeya-Zhang, C/2001 Q4 (NEAT) and C/2002 T7 (LINEAR), were performed at the Effelsberg 100-m Radio Telescope during their respective close approaches to Earth. None of the four lowest energy metastable lines (J,K=J),J=1--4, could be detected in these comets. We derive

P. Petit, J. -F. Donati, M. Auriere, J. D. Landstreet

We investigate the magnetic geometry of the active G8 dwarf xi Bootis A, from spectropolarimetric observations obtained in 2003 with the MuSiCoS echelle spectropolarimeter at the Telescope Bernard Lyot (Observatoire du Pic du Midi, France). We repeatedly detect a photospheric magnetic field, with periodic variations consistent with rotational modulation. Cir

M. Bejger

The effect of a soft phase core appearance in the center of polytropic star is analyzed by means of linear response theory. Approximate formulae for the changes of radius, moment of inertia and mass-energy of non-rotating configuration with arbitrary adiabatic indices are presented, followed by an example evaluation of astrophysical observables.

A. Barrau, C. Feron, J. Grain

In the framework of brane-world models lowering the Planck scale to the TeV range, it has recently been pointed out that small black holes could be formed at particle colliders or by neutrinos interactions in the atmosphere. This article aims at reviewing other places and epochs where microscopic black holes could be formed : the interstellar medium and the

Richard de Grijs

Near-infrared (NIR) integral-field spectroscopy (IFS) of violent starburst environments at high spatial (and spectral) resolution has the potential to revolutionise our ideas regarding the local interactions between the newly-formed massive stars and the interstellar medium (ISM) of their host galaxies. To illustrate this point, I present NIR IFS analysis of

J. Marti, D. Perez-Ramirez, J. L. Garrido, P. Luque-Escamilla

We present the results of a deep search for associated radio features in the vicinity of the microquasar Cygnus X-3. The motivation behind is to find out evidence for interaction between its relativistic jets and the surrounding interstellar medium, which could eventually allow us to perform calorimetry of the total energy released by this microquasar during

Floor van Leeuwen, Elena Fantino

We present an outline of a new reduction of the Hipparcos astrometric data, the justifications of which are described in the accompanying paper. The emphasis is on those aspects of the data analysis that are fundamentally different from the ones used for the catalogue published in 1997. The new reduction uses a dynamical modelling of the satellite&#39;s atti

Carmen Palomares

The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to operate on the International Space Station (ISS). The aim of AMS is the direct detection of charged particles in the rigidity range from 0.5 GV to few TV to perform high statistics studies of cosmic rays in space and search for antimatter and dark matter. This will be possible b

Alister W. Graham

This article reviews the popular reasons for the belief that dwarf elliptical galaxies and (ordinary) elliptical galaxies are distinct and separate species. They include: light-profile shape (or similarly image concentration); the magnitude-central surface brightness diagram; the magnitude-effective surface brightness diagram (or similarly the magnitude-effe

D. A. Green

The selection effects applicable to the identification of Galactic supernova remnants (SNRs) at radio wavelengths are discussed. Low surface brightness remnants are missing, as are those with small angular sizes (including young but distant SNRs). Several statistical properties of Galactic SNRs are discussed, including the surface-brightness/diameter (Sigma-

J. Petri, J. Kirk

The Stokes parameters of the pulsed synchrotron radiation produced in the striped pulsar wind model are computed and compared with optical observations of the Crab pulsar. We assume the main contribution to the wind emissivity comes from a thin transition layer where the dominant toroidal magnetic field reverses its polarity. The radial component of the fiel

J. -M. Wang, E. P. Zhang, B. Luo

Deep surveys of {\em Chandra} and {\em HST} (Hubble Space Telescope) show that active galactic nucleus (AGN) populations are changing with hard X-ray luminosities. This arises an interesting question whether the dusty torus is evolving with the central engines. We assemble a sample of 50 radio-quiet PG quasars to tackle this problem. The covering factors of

D0 Collaboration, V Abazov

We present a search for electroweak production of single top quarks in the s-channel and t-channel using neural networks for signal-background separation. We have analyzed 230 pb$^{-1}$ of data collected with the D0 detector at the Fermilab Tevatron Collider at a center-of-mass energy of 1.96 TeV and find no evidence for a single top quark signal. The result

Emil A. Yuzbashyan, Boris L. Altshuler, Vadim B. Kuznetsov, Victor Z. Enolskii

We obtain a complete solution for the mean-field dynamics of the BCS paired state with a large, but finite number of Cooper pairs in the non-adiabatic regime. We show that the problem reduces to a classical integrable Hamiltonian system and derive a complete set of its integrals of motion. The condensate exhibits irregular multi-frequency oscillations ergodi

Massimo Blasone, Antonio Capolupo, Francesco Terranova, Giuseppe Vitiello

We consider neutrino mixing and oscillations in quantum field theory and compute the neutrino lepton charge in decay processes where neutrinos are generated. We also discuss the proper definition of flavor charge and states and clarify the issues of the possibility of different mass parameters in field mixing.

Jun Pan, Istvan Szapudi

We measure the monopole moment of the three-point correlation function on scales $1\mpc-70\mpc$ in the Two degree Field Galaxy Redshift Survey (2dFGRS). Volume limited samples are constructed using a series of integral magnitudes bins between $M = -18 ... -22$. Our measurements with a novel edge-corrected estimator represent most, if not all, three-point lev

Stephen L. Adler

These are the commentaries for a volume of reprints of my selected papers with commentaries that I am preparing for publication by World Scientific. Contents: Preface; (1)Early Years, and Condensed Matter Physics; (2) High Energy Neutrino Reactions, PCAC Relations, and Sum Rules; (3) Anomalies: Chiral Anomalies and Their Nonrenormalization, Perturbative Corr

Michael J. Miller

Let S(n) be the set of all polynomials of degree n with all roots in the unit disk, and define d(P) to be the maximum of the distances from each of the roots of a polynomial P to that root&#39;s nearest critical point. In this notation, Sendov&#39;s conjecture asserts that d(P)<=1 for every P in S(n). Define P in S(n) to be locally extremal if d(P)>=d(Q) for

Steen H. Hansen, Ben Moore, Marcel Zemp, Joachim Stadel

Several general trends have been identified for equilibrated, self-gravitating collisionless systems, such as density or anisotropy profiles. These are integrated quantities which naturally depend on the underlying velocity distribution function (VDF) of the system. We study this VDF through a set of numerical simulations, which allow us to extract both the

Jan Fiala, Peter Kleban

The modified Farey sequence consists, at each level k, of rational fractions r_k^{(n)}, with n=1, 2, ...,2^k+1. We consider I_k^{(e)}, the total length of (one set of) alternate intervals between Farey fractions that are new (i.e., appear for the first time) at level k, I^{(e)}_k := \sum_{i=1}^{2^{k-2}} (r_k^{(4i)}- r_k^{(4i-2)}) . We prove that \liminf_{k\t

Ashkan Nikeghbali

In this paper, we study Bessel processes of dimension $δ\equiv2(1-μ)$, with $0<δ<2$, and some related martingales and random times. Our approach is based on martingale techniques and the general theory of stochastic processes (unlike the usual approach based on excursion theory), although for $0<δ<1$, these processes are even not semimartingales. The last ti

F. S. Felber

The Schwarzschild solution is used to find the exact relativistic motion of a payload in the gravitational field of a mass moving with constant velocity. At radial approach or recession speeds faster than 3^-1/2 times the speed of light, even a small mass gravitationally repels a payload. At relativistic speeds, a suitable mass can quickly propel a heavy pay

Gonzalo A. Palma

We introduce a simple scenario where, by starting with a five-dimensional SU(3) gauge theory, we end up with several 4-D parallel branes with localized fermions and gauge fields. Similar to the split fermion scenario, the confinement of fermions is generated by the nontrivial topological solution of a SU(3) scalar field. The 4-D fermions are found to be chir

Jose J. Blanco-Pillado, Gia Dvali, Michele Redi

In this work we derive non-singular BPS string solutions from an action that captures the essential features of a D-brane-anti-D-brane system compactified to four dimensions. The model we consider is a supersymmetric abelian Higgs model with a D-term potential coupled to an axion-dilaton multiplet. The strings in question are axionic D-term strings which we

N. Tsitverblit

Onset of small-amplitude oscillatory and both small- and finite-amplitude steady double-component convection arising due to component different boundary conditions in an infinite slot is studied for various slot orientations to the gravity. The main focus is on two compensating background gradients of the components. The physical mechanisms underlying steady

Yuri V. Lvov, Kurt L. Polzin, Esteban G. Tabak, Naoto Yokoyama

Steady scale-invariant solutions of a kinetic equation describing the statistics of oceanic internal gravity waves based on wave turbulence theory are investigated. It is shown in the non-rotating scale-invariant limit that the collision integral in the kinetic equation diverges for almost all spectral power-law exponents. These divergences come from resonan

F. S. Felber

Within the weak-field approximation of general relativity, new exact solutions are derived for the gravitational field of a mass moving with arbitrary velocity and acceleration. A mass having a constant velocity greater than 3^-1/2 times the speed of light gravitationally repels other masses at rest within a narrow cone. At high Lorentz factors (gamma >> 1),

S. K. Olson, R. Loloee, N. Theodoropoulou, W. P. Pratt

We compare specific resistances (AR equals area A times resistance R) of sputtered Pd/Pt interfaces measured in two different ways with no-free-parameter calculations. One way gives 2AR(Pd/Pt) of 0.29 (0.03) fohm-m(2) and the other 0.17 (0.13) fohm-m(2). From these we derive a best estimate of 2AR(Pd/Pt) of 0.28 (0.06) fohm-m(2), which overlaps with no-free-

J. Zhang, A. Kamenev, B. I. Shklovskii

We consider ion transport through protein ion channels in lipid membranes and water-filled nanopores in silicon films. It is known that, due to the large ratio of dielectric constants of water and the surrounding material, an ion placed inside the channel faces a large electrostatic self-energy barrier. The barrier leads to an exponentially large resistance

V. M. Garcia-Suarez, A. R. Rocha, S. W. Bailey, C. J. Lambert

Using first principles simulations we perform a detailed study of the structural, electronic and transport properties of monoatomic platinum chains, sandwiched between platinum electrodes. First we demonstrate that the most stable atomic configuration corresponds to a zigzag arrangement that gradually straightens as the chains are stretched. Secondly, we fin

Thomas House, Eran Palti

In this paper we consider compactifications of massive type IIA supergravity on manifolds with SU(3) structure. We derive the gravitino mass matrix of the effective four-dimensional N = 2 theory and show that vacuum expectation values of the scalar fields naturally induce spontaneous partial supersymmetry breaking. We go on to derive the superpotential and t

N. Schuch, M. M. Wolf, J. I. Cirac

We investigate the creation of squeezing via operations subject to noise and losses and ask for the optimal use of such devices when supplemented by noiseless passive operations. Both single and repeated uses of the device are optimized analytically and it is proven that in the latter case the squeezing converges exponentially fast to its asymptotic optimum,

M. V. Bashevoy, V. A. Fedotov, N. I. Zheludev

The power-flow lines of light interacting with a metallic nanoparticle, in the proximity of its plasmon resonance, form whirlpool-like nanoscale optical vortices. Two different types of vortex have been detected. The outward vortex first penetrates the particle near its centerline then, on exiting the particle, the flow-lines turn away from the centerline an

Jorma Louko, Alberto Molgado

We investigate refined algebraic quantisation of the constrained Hamiltonian system introduced by Boulware as a simplified version of the Ashtekar-Horowitz model. The dimension of the physical Hilbert space is finite and asymptotes in the semiclassical limit to 1/(2π\hbar) times the volume of the reduced phase space. The representation of the physical observ

M. V. Karasev, T. A. Osborn

For manifolds $\cal M$ of noncompact type endowed with an affine connection (for example, the Levi-Civita connection) and a closed 2-form (magnetic field) we define a Hilbert algebra structure in the space $L^2(T^*\cal M)$ and construct an irreducible representation of this algebra in $L^2(\cal M)$. This algebra is automatically extended to polynomial in mom

Jessica Sidman, Adam Van Tuyl, Haohao Wang

Let S = k[x_1,...,x_n] be a Z^r-graded ring with deg (x_i) = a_i \in Z^r for each i and suppose that M is a finitely generated Z^r-graded S-module. In this paper we describe how to find finite subsets of Z^r containing the multidegrees of the minimal multigraded syzygies of M. To find such a set, we first coarsen the grading of M so that we can view M as a Z

B. Kocsis, Z. Frei, Z. Haiman, K. Menou

The gravitational waves (GW) emitted during the coalescence of supermassive black holes (SMBHs) in the mass range 10^4-10^7 M_sun will be detectable out to high redshifts with LISA. We calculate the size and orientation of the three-dimensional error ellipse in solid angle and redshift within which the LISA event could be localized using the GW signatures al

Thorsten Renk, Steffen A. Bass, Dinesh K. Srivastava

We study the role played by the Landau-Pomeranchuk-Midgal (LPM) effect in relativistic collisions of hadrons and heavy nuclei, within a parton cascade model. We find that the LPM effect strongly affects the gluon multiplication due to radiation and considerably alters the space-time evolution of the dynamics of the collision. It ensures a multiplicity distri

Erik Palmgren

A modified realisability interpretation of infinitary logic is formalised and proved sound in constructive type theory (CTT). The logic considered subsumes first order logic. The interpretation makes it possible to extract programs with simplified types and to incorporate and reason about them in CTT.

H. Nikolic

Classical statistical particle mechanics in the configuration space can be represented by a nonlinear Schrodinger equation. Even without assuming the existence of deterministic particle trajectories, the resulting quantum-like statistical interpretation is sufficient to predict all measurable results of classical mechanics. In the classical case, the wave fu

Seok Kim, Joris Raeymaekers

Recently, Gaiotto, Strominger and Yin have proposed a holographic dual description for the near-horizon physics of certain N=2 black holes in terms of the superconformal quantum mechanics on D0-branes in the attractor geometry. We provide further evidence for their proposal by applying it to the case of `small&#39; black holes which have vanishing horizon ar

Luis P. Chimento, Diego Pavon

In this paper we show that by considering a universe dominated by two interacting components a superaccelerated expansion can be obtained from a decelerated one by applying a dual transformation that leaves the Einstein&#39;s field equations invariant.

Pierre Jammes

Let F be a riemannian flow on a closed manifold M. We study the behavior of the first eigenvalues of the Hodge Laplacian acting on differential forms under adiabatic collapsing of the flow. We show that the number of small eigenvalues is related to the basic cohomology of F, and give spectral criteria for the vanishing of the Álvarez class and the Euler clas

S. B. Popov, M. E. Prokhorov

Among a dozen known magnetar candidates there are no binary objects. As an estimate of a fraction of binary neutron stars is about 10% it is reasonable to address the question of solitarity of magnetars, to estimate theoretically the fraction of binary objects among them, and to mark o probable companions. We present population synthesis calculations of bina

Yungui Gong, Yuan-Zhong Zhang

The holographic principle is used to discuss the holographic dark energy model. We find that the Bekenstein-Hawking entropy bound is far from saturation under certain conditions. A more general constraint on the parameter of the holographic dark energy model is also derived.

Franz Gähler, John Hunton, Johannes Kellendonk

The first author&#39;s recent unexpected discovery of torsion in the integral cohomology of the Tübingen Triangle Tiling has led to a re-evaluation of current descriptions of and calculational methods for the topological invariants associated with aperiodic tilings. The existence of torsion calls into question the previously assumed equivalence of cohomologi

F. W. S. Lima, D. Stauffer

On directed lattices, with half as many neighbours as in the usual undirected lattices, the Ising model does not seem to show a spontaneous magnetisation, at least for lower dimensions. Instead, the decay time for flipping of the magnetisation follows an Arrhenius law on the square and simple cubic lattice. On directed Barabasi-Albert networks with two and s

Kirill Krasnov

A generalization of the matrix model idea to quantum gravity in three and higher dimensions is known as group field theory (GFT). In this paper we study generalized GFT models that can be used to describe 3D quantum gravity coupled to point particles. The generalization considered is that of replacing the group leading to pure quantum gravity by the twisted

E. Shintani, S. Aoki, N. Ishizuka, K. Kanaya

We carry out a feasibility study for the lattice QCD calculation of the neutron electric dipole moment (NEDM) in the presence of the $θ$ term. We develop the strategy to obtain the nucleon EDM from the CP-odd electromagnetic form factor $F_3$ at small $θ$, in which NEDM is given by $\lim_{q^2\to 0}θF_3(q^2)/(2m_N)$ where $q$ is the momentum transfer and $m_N

Amina Helmi, J. F. Navarro, B. Nordstrom, J. Holmberg

We search for signatures of past accretion events in the Milky Way in the recently published catalogue by Nordstrom et al.(2004), containing accurate spatial and kinematic information as well as metallicities for 13240 nearby stars. To optimize our strategy, we use numerical simulations to characterize the properties of the debris from disrupted satellites.

H. Kamei, K. Miyake

Possibility of a quartet superfluidity in fermionic systems is studied as a new aspect of atomic gas at ultra low temperatures. The four-fold degeneracy of hyperfine state and moderate coupling is indispensable for the quartet superfluidity to occur. Possible superconductivity with quartet condensation in electron systems is discussed.

Domenico Fiorenza, Lucian M. Ionescu

Kontsevich&#39;s formality theorem and the consequent star-product formula rely on the construction of an $L_\infty$-morphism between the DGLA of polyvector fields and the DGLA of polydifferential operators. This construction uses a version of graphical calculus. In this article we present the details of this graphical calculus with emphasis on its algebraic

Susumu Inoue, Felix A. Aharonian, Naoshi Sugiyama

All sufficiently massive clusters of galaxies are expected to be surrounded by strong accretion shocks, where protons can be accelerated to $\sim 10^{18}$-$10^{19}$ eV under plausible conditions. Such protons interact with the cosmic microwave background and efficiently produce very high energy electron-positron pairs, which then radiate synchrotron and inve

C. J. Tessone, A. Scire, R. Toral, P. Colet

We develop a theory for the emergence of global firings in non-identical excitable systems subject to noise. Three different dynamical regimes arise: sub-threshold motion, where all elements remain confined near the fixed point; coherent pulsations, where a macroscopic fraction fire simultaneously; and incoherent pulsations, where units fire in a disordered

L. V. Fil&#39;kov, V. L. Kashevarov

A fit of the experimental data to the total cross section of the process γγ->π^0π^0 in the energy region from 270 to 2250 MeV has been carried out using dispersion relations for the invariant amplitudes where the quadrupole polarizabilities are free parameters. As a result the sum and difference of the electric and magnetic quadrupole polarizabilities of the

Christian Liedtke

For the Galois closure $\Xgal$ of a generic projection from a surface $X$, it is believed that $\pi_1(\Xgal)$ gives rise to new invariants of $X$. However, in all examples this group is surprisingly simple. In this article, we offer an explanation for this phenomenon: We compute a quotient of $\pi_1(\Xgal)$ that depends on $\pi_1(X)$ and data from the generi

F. Buisseret, C. Semay

A new method to study the retardation effects in mesons is presented. Inspired from the covariant oscillator quark model, it is applied to the rotating string model in which a non zero value is allowed for the relative time between the quark and the antiquark. This approach leads to a retardation term which behaves as a perturbation of the meson mass operato

Kazuhide Ichikawa, Masahiro Kawasaki, Fuminobu Takahashi

We study how the oscillations of the neutrinos affect their thermalization process during the reheating period with temperature O(1) MeV in the early universe. We follow the evolution of the neutrino density matrices and investigate how the predictions of big bang nucleosynthesis vary with the reheating temperature. For the reheating temperature of several M

Henri-Hugues Fliche, Jean-Marie Souriau, Roland Triay

We investigate the dynamics of an homogenous distribution of galaxies moving under the cosmological expansion through Euler-Poisson equations system. The solutions are interpreted with the aim of understanding the cosmic velocity fields in the Local Super Cluster, and in particular the presence of a bulk flow. Among several solutions, we shows a planar kinem

M. Kawasaki, T. Yanagida

We show that the $e^++e^-$ decay of a light scalar boson of mass 1-10 MeV may account for the fluxes of 511 keV gamma ray observed by SPI/INTEGRAL. We argue that candidates of such a light scalar boson is one of the string moduli or a scalar partner of the axion in a supersymmetric theory.

E. Bagan, R. Munoz-Tapia

We review the optimal protocols for aligning spatial frames using quantum systems. The communication problem addressed here concerns a type of information that cannot be digitalized. Asher Peres referred to it as &#34;unspeakable information&#34;. We comment on his contribution to this subject and give a brief account of his scientific interaction with the a

Peter P. Rohde, Timothy C. Ralph, Michael A. Nielsen

Photonic quantum information processing schemes, such as linear optics quantum computing, and other experiments relying on single-photon interference, inherently require complete photon indistinguishability to enable the desired photonic interactions to take place. Mode-mismatch is the dominant cause of photon distinguishability in optical circuits. Here we