May 2005 arXiv papers — page 13

Alessandro Fabbri, Jose Navarro-Salas

The presence of gravity implies corrections to the Einstein-Planck formula $E=h ν$. This gives hope that the divergent blueshift in frequency, associated to the presence of a black hole horizon, could be smoothed out for the energy. Using simple arguments based on Einstein's equivalence principle we show that this is only possible if a black hole emits,

Mostafa El-Khamy, Robert J. McEliece

A closed form formula of the partition weight enumerator of maximum distance separable (MDS) codes is derived for an arbitrary number of partitions. Using this result, some properties of MDS codes are discussed. The results are extended for the average binary image of MDS codes in finite fields of characteristic two. As an application, we study the multiuser

A. Kack, F. K. Wilhelm

We present a superconducting circuit consisting of a flux qubit and a single-charge transistor serving as a detector. As flux and charge are conjugate, the transistor can detect states of the qubit close to the flux degeneracy point, when the eigenstates are quantum superpositions of fluxes. The coupling has a flip-flop symmetry conserving the total number o

Hans-Andreas Engel, Bertrand I. Halperin, Emmanuel I. Rashba

We develop a theory of extrinsic spin currents in semiconductors, resulting from spin-orbit coupling at charged scatterers, which leads to skew scattering and side jump contributions to the spin Hall conductance. Applying the theory to bulk n-GaAs, without any free parameters, we find spin currents that are in reasonable agreement with recent experiments by

Xin Wan, D. N. Sheng, E. H. Rezayi, Kun Yang

We study the behavior of two-dimensional electron gas in the fractional quantum Hall regime in the presence of finite layer thickness and correlated disordered potential. Generalizing the Chern number calculation to many-body systems, we determine the mobility gaps of fractional quantum Hall states based on the distribution of Chern numbers in a microscopic

F. D. M. Haldane

A course of four lectures given at the International School of Physics "Enrico Fermi", Varenna, Italy, July 1992, in which the underlying algebraic structure needed for bosonization of the Fermi surface in two- or three-dimensions was first described. This is an unchanged 1993 preprint version of a published but hard-to-find (and often mis-cited) 199

Hisatsugu Yamasaki, Yuhei Natsume, Katsuhiro Nakamura

To show a mechanism leading to the breakdown of a particle picture for the multi-component Bose-Einstein condensates(BECs) with a harmonic trap in high dimensions, we investigate the corresponding 2-$d$ nonlinear Schr{ö}dinger equation (Gross-Pitaevskii equation) with use of a modified variational principle. A molecule of two identical Gaussian wavepackets h

Kalpana Awasthi, Anchal Srivastava, O. N. Srivastava

Carbon nanotubes play a fundamental role in the rapidly developing field of nanoscience and nanotechnology because of their unique properties and high potential applictions. In this article, the different synthesis method of CNTs are reviewed. From the industrial point of view, the chemical vapor depostion method has shown advantages over electric arc discha

Banibrata Mukhopadhyay

Propagation of a fermion in curved space-time generates a gravitational interaction due to coupling of its spin with the space-time curvature connection. This gravitational interaction, which is an axial-four-vector multiplied by a four gravitational vector potential, appears as a CPT violating term in the Lagrangian which generates an opposite sign and thus

D. Fargion

The Earth's Shadow to Cosmic Rays offer a windows to Tau Neutrino Astronomy at the Horizon edges. Inclined and Horizontal C.R. Showers (70^o-90^o zenith angle) produce secondary (gamma,e) mostly suppressed by high column atmosphere depth. The shower Cherenkov photons are diluted and filtered by air opacity, but secondary penetrating, muon pairs and their

E. Moulin, D. Santos

MIMAC-He3 (MIcro-tpc MAtrix of Chambers of Helium 3) is a project for direct detection of non-baryonic dark matter search using He3 as sensitive medium. The priviledged properties of He3 are highlighted. The double detection : ionization and track projection, is explained and rejection evaluated. A phenomenological study in effective SUSY models has been to

Eduardo Rubio-Herrera, William H. Lee

We present a numerical study of the global modes of oscillation of thick accretion discs around black holes. We have previously studied the case of constant distributions of specific angular momentum. In this second paper, we investigate (i) how the size of the disc affects the oscillation eigenfrequencies, and (ii) the effect of power-law distributions of a

D. M. Ghilencea, Hyun Min Lee

We discuss the role that higher derivative operators play in field theory orbifold compactifications on S_1/Z_2 with local and non-local (Scherk-Schwarz) breaking of supersymmetry. Integrating out the bulk fields generates brane-localised higher derivative counterterms to the mass of the brane (or zero-mode of the bulk) scalar field, identified with the Higg

Masamune Oguri, Masahiro Takada, Keiichi Umetsu, Tom Broadhurst

The steep mass profile of A1689 derived from recent detailed lensing observations is not readily reconciled with the low concentration halos predicted by the standard CDM model. However, halo triaxiality may act to bias the profile constraints derived assuming a spherically symmetric mass distribution, since lensing relates only to the projected mass distrib

D. Boyanovsky

Neutrino collective excitations are studied in the Standard Model at high temperatures below the symmetry breaking scale. Two parameters determine the properties of the collective excitations: a mass scale $m_ν=gT/4$ which determines the \emph{chirally symmetric} gaps in the spectrum and $Δ=M^2_W(T)/2m_νT$. The spectrum consists of left handed negative helic

Jan B. Gutowski, Wafic Sabra

The classification of 1/4-supersymmetric solutions of five dimensional gauged supergravity coupled to arbitrary many abelian vector multiplets, which was initiated in hep-th/0401129, is completed. The structure of all solutions for which the Killing vector constructed from the Killing spinor is null is investigated in both the gauged and the ungauged theorie

A. Udalski, M. Jaroszynski, B. Paczynski, M. Kubiak

We report the discovery of a several-Jupiter mass planetary companion to the primary lens star in microlensing event OGLE-2005-BLG-071. Precise (<1%) photometry at the peak of the event yields an extremely high signal-to-noise ratio detection of a deviation from the light curve expected from an isolated lens. The planetary character of this deviation is easi

Keisuke Taniguchi, Thomas W. Baumgarte, Joshua A. Faber, Stuart L. Shapiro

We present new sequences of general relativistic, quasiequilibrium black hole-neutron star binaries. We solve for the gravitational field in the conformal thin-sandwich decomposition of Einstein&#39;s field equations, coupled to the equations of relativistic hydrostatic equilibrium for a perfect fluid. We account for the black hole by solving these equations

S. Masood, S. Nasri, J. Schechter

We note that the fine structure at the endpoint region of the beta decay spectrum is now essentially known using neutrino oscillation data, if the mass of one neutrino is specified. This may help to identify the effects of nonzero neutrino masses in future experiments. An exact treatment of phase space kinematics is used. This work is independent of theoreti

Antonio J. R. da Silva, A. Fazzio, Raimundo R. dos Santos, Luiz E. Oliveira

We perform a theoretical study, using {\it ab initio} total energy density-functional calculations, of the effects of disorder on the $Mn-Mn$ exchange interactions for $Ga_{1-x}Mn_xAs$ diluted semiconductors. For a 128 atoms supercell, we consider a variety of configurations with 2, 3 and 4 Mn atoms, which correspond to concentrations of 3.1%, 4.7%, and 6.3%

Dirk Tasche

We investigate a multi-factor extension of the asymptotic single risk factor (ASRF) model that underlies the capital charges of the &#34;Basel II Accord&#34;. In this extended model, it is still possible to derive closed-form solutions for the risk contributions to Value-at-Risk and Expected Shortfall. As an application of the risk contribution formulae we i

Michael Stone, Suk Bum Chung

The &#34;half-quantum&#34; vortices ($σ$) and quasiparticles ($ψ$) in a two-dimensional $p_x+ip_y$ superconductor obey the Ising-like fusion rules $ψ\times ψ=1$, $σ\times ψ=σ$, and $σ\times σ= 1+ψ$. We explain how the physical fusion of vortex-antivortex pairs allows us to use these rules to read out the information encoded in the topologically protected spa

Daniel Arean, Angel Paredes, Alfonso V. Ramallo

We study the addition of flavor degrees of freedom to the supergravity dual of the non-commutative deformation of the maximally supersymmetric gauge theories. By considering D7 flavor branes in the probe approximation and studying their fluctuations we extract the spectrum of scalar and vector mesons as a function of the non-commutativity. We find that the s

Gonzalo J. Olmo

In this work we show that the gravity lagrangian f(R) at relatively low curvatures in both metric and Palatini formalisms is a bounded function that can only depart from the linearity within the limits defined by well known functions. We obtain those functions by analysing a set of inequalities that any f(R) theory must satisfy in order to be compatible with

Ansar Fayyauddin, Tasneem Zehra Husain

We characterize the geometry produced by M5-branes wrapping a Special Lagrangian 3-cycle in a Calabi-Yau 3-fold. The presence of the brane replaces the the Calabi-Yau by a real manifold with an almost complex structure. We show that, in this classification, a distinguished (1,1) form as well as a globally defined (3,0) form play an important role. The requir

Chris J. Willott

Two recent studies based on composite reddened quasar spectra have indicated the presence of `gray&#39; dust in quasar environments. This gray dust has a relatively flat extinction law in the UV, consistent with the theoretical expectation of a lack of small dust grains close to a quasar. In contrast, individual reddened quasars in the Sloan Digital Sky Surv

Asantha Cooray

(Summary) Making use of scaling relations between the central and the total galaxy luminosity of a dark matter halo as a function of the halo mass, and the scatter in these relations, we present an empirical model to describe the luminosity function (LF) of galaxies. We extend this model to describe relative statistics of early-type, or red, and late-type, o

Qing-feng Sun, X. C. Xie

The spin-orbit coupling systems with a zero magnetic field is studied under the equilibrium situation, {\it i.e.}, without a voltage bias. A persistent spin current is predicted to exist under most circumstances, although the persistent charge current and the spin accumulation are identically zero. In particular, a two-dimensional quantum wire is investigate

J. Berges, Sz. Borsanyi, C. Wetterich

Isotropization occurs on time scales much shorter than the thermal equilibration time. This is a crucial ingredient for the understanding of collision experiments of heavy nuclei or other nonequilibrium phenomena in complex many body systems. We discuss in detail the limitations of estimates based on standard ``linear&#39;&#39; or relaxation-time approximati

C. Scannapieco, P. B. Tissera, S. D. M. White, V. Springel

We discuss a model for treating chemical enrichment by SNII and SNIa explosions in simulations of cosmological structure formation. Our model includes metal-dependent radiative cooling and star formation in dense collapsed gas clumps. Metals are returned into the diffuse interstellar medium by star particles using a local SPH smoothing kernel. A variety of c

G. Huetsi

In this paper we study the clustering of SZ-selected galaxy clusters on a past light-cone, particularly paying attention to the possibility of constraining properties of dark energy. The prospects of detecting baryonic features in the cluster power spectrum for a wide and shallow survey like PLANCK, and for an SPT-like narrow and deep survey are discussed. I

Sigbjorn Hervik, Alan Coley

Recently it was shown that the exact cosmological solutions known as the vacuum plane-wave solutions are late-time attractors for an open set of the spatially homogeneous Bianchi universes containing a non-inflationary $γ$-law perfect fluid. In this paper we study inhomogeneous perturbations of these plane-wave spacetimes. By using expansion-normalised scale

J. O. Fossum, Y. Meheust, K. P. S. Parmar, K. D. Knudsen

Microscopy observations show that suspensions of synthetic and natural nano-layered smectite clay particles submitted to a strong external electric field undergo a fast and extended structuring. This structuring results from the interaction between induced electric dipoles, and is only possible for particles with suitable polarization properties. Smectite cl

Anindya Mukherjee, Sunil Mukhi

We give an explicit demonstration of the equivalence between the Normal Matrix Model (NMM) of c=1 string theory at selfdual radius and the Kontsevich-Penner (KP) model for the same string theory. We relate macroscopic loop expectation values in the NMM to condensates of the closed string tachyon, and discuss the implications for open-closed duality. As in c<

Leif Lonnblad, Malin Sjodahl, Torsten Akesson

Possible consequences of the production of small black holes at the LHC for different scenarios with large extra dimensions are investigated. The effects from black hole production on some standard jet observables are examined, concentrating on the reduction of the QCD cross section. It is found that black hole production of partons interacting on a short en

Rochus Klesse, Sandra Frank

We consider quantum error correction of quantum-noise that is created by a local interaction of qubits with a common bosonic bath. The possible exchange of bath bosons between qubits gives rise to spatial and temporal correlations in the noise. We find that these kind of noise correlations have a strong negative impact on quantum error correction.

Roberto Franzosi, Marco Pettini

In this second paper, we prove a necessity Theorem about the topological origin of phase transitions. We consider physical systems described by smooth microscopic interaction potentials V_N(q), among N degrees of freedom, and the associated family of configuration space submanifolds {M_v}_{v \in R}, with M_v={q \in R^N | V_N(q) \leq v}. On the basis of an an

Roberto Franzosi, Marco Pettini, Lionel Spinelli

In this first paper, we demonstrate a theorem that establishes a first step toward proving a necessary topological condition for the occurrence of first or second order phase transitions: we prove that the topology of certain submanifolds of configuration space must necessarily change at the phase transition point. The theorem applies to smooth, finite-range

Richard Easther, William H. Kinney, Hiranya Peiris

We contrast two approaches to calculating trans-Planckian corrections to the inflationary perturbation spectrum: the New Physics Hypersurface [NPH] model, in which modes are normalized when their physical wavelength first exceeds a critical value, and the Boundary Effective Field Theory [BEFT] approach, where the initial conditions for all modes are set at t

F. Haas

The most general Jacobi brackets in $\mathbb{R}^3$ are constructed after solving the equations imposed by the Jacobi identity. Two classes of Jacobi brackets were identified, according to the rank of the Jacobi structures. The associated Hamiltonian vector fields are also constructed.

Magdalena Kunert-Bajraszewska, Andrzej Marecki, Peter Thomasson, Ralph E. Spencer

A new sample of candidate Compact Steep Spectrum (CSS) sources that are much weaker than the CSS source prototypes has been selected from the VLA FIRST catalogue. MERLIN `snapshot&#39; observations of the sources at 5 GHz indicate that six of them have an FR II-like morphology, but are not edge-brightened as is normal for Medium-sized Symmetric Objects (MSOs

Lorenzo Iorio

The impact of the latest combined CHAMP/GRACE/terrestrial measurements Earth gravity model EIGEN-CG03C on the measurement of the Lense-Thirring effect with some linear combinations of the nodes of some of the existing Earth&#39;s artificial satellites is presented. The 1-sigma upper bound of the systematic error in the node-node LAGEOS-LAGEOS II combination

J. Eisert, D. Gross

We review the theory of multi-particle entanglement. In this book chapter we aim at briefly ``setting the coordinates&#39;&#39; and guiding through the extensive literature in this field. Our coordinate system chosen for this chapter has the axes labeled pure and mixed states on the one hand, entanglement in single specimens and the asymptotic setting on the

Vivi Petersen, Lars Bojer Madsen, Klaus Molmer

We present a Gaussian state description of squeezed light generated in an optical parametric oscillator. Using the Gaussian state description we describe the dynamics of the system conditioned on homodyne detection on the output field. Our theory shows that the output field is squeezed only if observed for long enough times or by a detector with finite bandw

B. Lazarovits, L. Szunyogh, P. Weinberger

We present a theoretical study of surface states close to 3d transition metal adatoms (Cr, Mn, Fe, Co, Ni and Cu) on a Cu(111) surface in terms of an embedding technique using the fully relativistic Korringa-Kohn-Rostoker method. For each of the adatoms we found resonances in the s-like states to be attributed to a localization of the surface states in the p

Ch. Hoffmann, M. Lücke, A. Pinter

Numerical calculations of vortex flows in Taylor-Couette systems with counter rotating cylinders are presented. The full, time dependent Navier-Stokes equations are solved with a combination of a finite difference and a Galerkin method. Annular gaps of radius ratio $η=0.5$ and of several heights are simulated. They are closed by nonrotating lids that produce

Floor van Leeuwen

A critical assessment of the quality of the Hipparcos data, partly supported by a completely new analysis of the raw data, is presented with the aim of clarifying reliability issues that have surfaced since the publication of the Hipparcos catalogue in 1997. A number of defects in the data are identified, such as scan-phase discontinuities and effects of ext

Alberto Diez-Tejedor, Alexander Feinstein

We show that short-range interactions between the fundamental particles in the universe can drive a period of accelerated expansion. This description fits the early universe. In the present day universe, if one postulates short-range interactions or a sort of &#34;shielded gravity&#34;, the picture may repeat.

G. E. Volovik

We compare quantum hydrodynamics and quantum gravity. They share many common features. In particular, both have quadratic divergences, and both lead to the problem of the vacuum energy, which in the quantum gravity transforms to the cosmological constant problem. We show that in quantum liquids the vacuum energy density is not determined by the quantum zero-

A. Driouich, O. El-Mennaoui, M. Jazar

In this paper we are interested in spectral decomposition of an unbounded operator with discrete spectrum. We show that if $A$ generates a polynomially bounded $n$-times integrated group whose spectrum set $σ(A)=\{iλ_k; k\in\mathbb{Z}^* \}$ is discrete and satisfies $\sum \frac{1}{|λ_k|^\ellδ_k^n}<\infty$ ($n$ and $\ell$ nonnegative integers), then there exi

Yasushi Takahashi, Yuhei Hayamizu, Hirotake Itoh, Masahiro Yoshita

We measured absorption spectra of T-shaped quantum wires at room temperature using waveguide-transmission spectroscopy. Strong and narrow room-temperature one-dimensional-exciton absorption peak was observed, which shows peak modal absorption coefficient of 160 cm$^{-1}$ per 20 wires with $Γ$-factor of $4.3\times10^{-3}$, width of 7.2 meV, and strong polariz

An Min Wang, Rengui Zhu

We prove strictly that one dimension spin 1/2 Heisenberg model has a symmetry of energy spectrum between its subspace $n$ and the subspace $L-n$ of the Fock space. Our proof is completed by introducing two general quantum operations. One is a flip operation of spin direction and another is a mirror reflection of spin sites.

A. D. Ribeiro, M. Novaes, M. A. M. de Aguiar

We propose a conjugate application of the Bargmann representation of quantum mechanics. Applying the Maslov method to the semiclassical connection formula between the two representations, we derive a uniform semiclassical approximation for the coherent state propagator which is finite at phase space caustics.

Keisuke Goda, Kirk McKenzie, Eugeniy E. Mikhailov, Ping Koy Lam

We study the effect of photothermal fluctuations on squeezed states of light through the photo-refractive effect and thermal expansion in a degenerate optical parametric amplifier (OPA). We also discuss the effect of the photothermal noise in various cases and how to minimize its undesirable consequences. We find that the photothermal noise in the OPA introd

S. Iblisdir, A. Acin, N. Gisin

We study machines that take N identical replicas of a pure qudit state as input and output a set of M_A clones of a given fidelity and another set of $M_B$ clones of another fidelity. The trade-off between these two fidelities is investigated, and numerous examples of optimal N -> M_A+M_B cloning machines are exhibited using a generic method. A generalisatio

J. Eisert, M. M. Wolf

This article provides an elementary introduction to Gaussian channels and their capacities. We review results on the classical, quantum, and entanglement assisted capacities and discuss related entropic quantities as well as additivity issues. Some of the known results are extended. In particular, it is shown that the quantum conditional entropy is maximized

Andreas Rathke

Recently, spectroscopic and calorimetric observations of hydrogen plasmas and chemical reactions with them have been interpreted as evidence for the existence of electronic states of the hydrogen atom with a binding energy of more than 13.6 eV. The theoretical basis for such states, that have been dubbed hydrinos, is investigated. We discuss both, the novel

S. Nasiri, H. Safari

Extended phase space (EPS) formulation of quantum statistical mechanics treats the ordinary phase space coordinates on the same footing and thereby permits the definite the canonical momenta conjugate to these coordinates . The extended lagrangian and extended hamiltonian are defined in EPS by the same procedure as one does for ordinary lagrangian and hamilt

Cristopher Moore, Alexander Russell

Recently Bacon, Childs and van Dam showed that the ``pretty good measurement&#39;&#39; (PGM) is optimal for the Hidden Subgroup Problem on the dihedral group D_n in the case where the hidden subgroup is chosen uniformly from the n involutions. We show that, for any group and any subgroup H, the PGM is the optimal one-register experiment in the case where the

Pieter Kok, Samuel L. Braunstein

We derive the relativistic transformation laws for the annihilation operators of the scalar field, the massive spin-1 vector field, the electromagnetic field and the spinor field. The technique developed here involves straightforward mathematical techniques based on fundamental quantum field theory, and is applicable to the study of entanglement in arbitrary

Georgy P. Karev

The dynamic theory of inhomogeneous populations developed during the last decade predicts several essential new dynamic regimes applicable even to the well-known, simple population models. We show that, in an inhomogeneous population with a distributed reproduction coefficient, the entire initial distribution of the coefficient should be used to investigate

E. Tostesen

Peaks in the probabilities of loops or bubbles, helical segments, and unzipping ends in melting DNA are found in this article using a peak finding method that maps the hierarchical structure of certain energy landscapes. The peaks indicate the alternative conformations that coexist in equilibrium and the range of their fluctuations. This yields a representat

Sophie Royer, Antoine Royer

A method for numerically integrating transport equations, combining transfer matrices, transmission-reflection matrices, and Green&#39;s matrices (TTRG), was recently proposed. The present paper deals specifically with azymuthally integrated radiances inside a horizontally homogeneous canopy of Lambertian leaves. Its main purpose is to test the accuracy of T

J. Ferrer, L. Fernandez-Seivane, J. M. Hernando, M. B. Castan

This report presents theoretical estimates of the Power Density levels which may be reached inside trains. Two possible sources of high levels of radiation are discussed. The first one arises since the walls of the wagons are metallic and therefore bounce back almost all radiation impinging on them. The second is due to the simultaneous emission of a seeming

Janusz Miskiewicz, Marcel Ausloos

A microscopic approach to macroeconomic features is intended. A model for macroeconomic behavior based on the Ausloos-Clippe-Pekalski model is built and investigated. The influence of a discrete time information transfer is investigated. The formation of economic cycles is observed as a function of the time of information delay. Three regions of delay time a

T. D. Carozzi, A. M. Buckley

We derive the second-order sampling properties of certain autocovariance and autocorrelation estimators for sequences of independent and identically distributed samples. Specifically, the estimators we consider are the classic lag windowed correlogram, the correlogram with subtracted sample mean, and the fixed-length summation correlogram. For each correlogr

Andres R. R. Papa, Luiz M. Barreto, Ney A. B. Seixas

Threshold systems appear to underlie the global behaviour of physical phenomena very unlike at a first look. The usual experimental fingerprint of threshold system grounded phenomena is the presence of power laws. Experimental evidence has been found, for example, in superconductor vortex avalanches, sand piles, the brain, 4He superfluidity and earthquakes.

Olga Barannikova

Significant baryon over meson enhancement was measured at RHIC in the intermediate transverse momentum range of $p_T=2-4$ GeV/$c$ (&#34;baryon-meson puzzle&#34;). With STAR detector we were able to extend particle identification towards higher transverse momentum offering further insights into the particle production mechanisms at intermediate to high $p_T$.

Sebastian N. White

Soon after the LHC is commissioned with proton beams the ATLAS experiment will begin studies of Pb-Pb collisions with a center of mass energy of ?sNN = 5.5 TeV. The ATLAS program is a natural extension of measurements at RHIC in a direction that exploits the higher LHC energies and the superb ATLAS calorimeter and tracking coverage. At LHC energies, collisio

Parravano Antonio

The evolution of networks of coupled chaotic maps with delayed interactions can be studied in the usual way by analyzing the evolution of the state of elements at each iteration time (the &#34;Simulator&#34; point of view), or it can be analyzed from the point of view of a single element (the &#34;Observer&#34; perspective) that is receiving delayed informat

S. I. Vainshtein

Using experimental transverse velocities data for very high Reynolds number turbulence, we suggest a model describing both formation of intermittency and asymmetry of turbulence. The model, called &#34;bump-model&#34; is a modification of ramp-model suggested earlier, S.I. Vainshtein and K.R. Sreenivasan, Phys. Rev. Lett., 73, 3085 (1994). The connection bet

P. K. Papachristou, E. Mavrommatis, V. Constantoudis, F. Diakonos

We consider the relation between relaxation time and the largest Lyapunov exponent in a system of two coupled oscillators, one of them being harmonic. It has been found that in a rather broad region of parameter space, contrary to the common expectation, both Lyapunov exponent and relaxation time increase as a function of the total energy. This effect is att

Yu. A. Grigoryev, A. V. Tsiganov

We discuss computer implementation of the known algorithm of finding separation coordinates for the special class of orthogonal separable systems called L-systems or Benenti systems.

Pierluigi Contucci, Cristian Giardina&#39;

If the variance of a Gaussian spin-glass Hamiltonian grows like the volume the model fulfills the Ghirlanda-Guerra identities in terms of the normalized Hamiltonian covariance.

Roberto Franzosi, Marco Pettini, Lionel Spinelli

An emended and improved version of the present paper has been archived in math-ph/0505057, and a preliminary account of its content has been published in Phys.Rev.Lett. 92, 60601, (2004). Moreover, in order to prove the relevance of topology for phase transition phenomena in a broad domain of physically interesting cases, we have proved another theorem which

Jim Hoste, Patrick D. Shanahan

We describe an algorithm for computing boundary slopes of 2-bridge links. As an example, we work out the slopes of the links obtained by 1/k surgery on one component of the Borromean rings. A table of all boundary slopes of all 2-bridge links with 10 or less crossings is also included.

Alessandra Sarti

In a previous paper, math.AG/0409419, we described six families of K3-surfaces with Picard-number 19, and we identified surfaces with Picard-number 20. In these notes we classify some of the surfaces by computing their transcendental lattices. Moreover we show that the surfaces with Picard-number 19 are birational to a Kummer surface which is the quotient of

Mario Micallef, Jon Wolfson

A well known consequence of the Wirtinger inequality is that in a Kaehler surface a holomorphic curve is an area minimizer in its homology class. In light of this result it is natural, given a Kaehler surface, to investigate the relation between area minimizers and complex curves. When the Kaehler surface is a K3 surface this problem takes on a new character

Joël De Coninck, François Dunlop, Thierry Huillet

In a probabilistic model of a film over a disordered substrate, Monte-Carlo simulations show that the film hangs from peaks of the substrate. The film profile is well approximated by a necklace of Wulff shapes. Such a necklace can be obtained as the infimum of a collection of Wulff shapes resting on the substrate. When the random substrate is given by iid he

Lingaraj Sahu

Using coordinate-free basic operators on toy Fock spaces \cite{AP}, quantum random walks are defined following the ideas in \cite{LP,AP}. Strong convergence of quantum random walks associated with bounded structure maps is proved under suitable assumptions, extendings the result obtained in \cite{KBS} in case of one dimensional noise. To handle infinite dime

Renaat Van Malderen

Bernoulli numbers are usually expressed in terms of their lower index numbers (recursive). This paper gives explicit formulas for Bernoulli numbers of even index. The formulas contain a remarkable sequence of determinants. The value of these determinants for variable dimension is investigated.

Eli Bagno, David Garber

We generalize the results of Ksavrelof and Zeng about the multidistribution of the excedance number of $S_n$ with some natural parameters to the colored permutation group and to the Coxeter group of type $D$. We define two different orders on these groups which induce two different excedance numbers. Surprisingly, in the case of the colored permutation group

Miguel Ángel Marco-Buzunáriz

In this paper we define the combinatorial analogous of a pencil, and show its relationship with the concept of admissibility. Such an object is usefull to study the isomorphisms between fundamental groups of the complements of line arrangement with the same combinatorial type. This definition generalizes the idea of net given by Yuzvinsky and others. The mai

Jonathan Hillman, Daniel Matei, Masanori Morishita

For a link $L$ in the 3-sphere and for a prime $p$, we express the $p$-primary information on the first homology group of $p^{m}$-fold branched covers of $L$ in terms of its $p$-adic Milnor higher linking invariants, using the completed Alexander module of the pro-$p$ completion of the link group of $L$.

Victor Batyrev, Maximilian Kreuzer

In this paper, we compute the integral cohomology groups for all examples of Calabi-Yau 3-folds obtained from hypersurfaces in 4-dimensional Gorenstein toric Fano varieties. Among 473 800 776 families of Calabi-Yau 3-folds $X$ corresponding to 4-dimensional reflexive polytopes there exist exactly 32 families having non-trivial torsion in $H^*(X, \Z)$. We cam

Johann K. Leida

Lie groupoids generalize transformation groups, and so provide a natural language for studying orbifolds and other noncommutative geometries. In this paper, we investigate a connection between orbifolds and equivariant stable homotopy theory using such groupoids. A different sort of twisted sector, along with a classical theorem of tom Dieck, allows for a na

Kazuhiro Kuwae, Takashi Shioya

We introduce a natural definition of $L^p$-convergence of maps, $p \ge 1$, in the case where the domain is a convergent sequence of measured metric space with respect to the measured Gromov-Hausdorff topology and the target is a Gromov-Hausdorff convergent sequence. With the $L^p$-convergence, we establish a theory of variational convergences. We prove that

S. Buyalo

We prove that every visual Gromov hyperbolic space X whose boundary at infinity has the finite capacity dimension n admits a quasi-isometric embedding into (n+1)-fold product of metric trees.

S. Buyalo

We introduce a quasi-symmetry invariant of a metric space Z called the capacity dimension. Our main result says that for a visual Gromov hyperbolic space X the asymptotic dimension of X is at most the capacity dimension of its boundary at infinity plus 1.

Leonhard Euler

In this paper, Euler gives the general trionomial coefficient as a sum of the binomial coefficients, the general quadrinomial coefficient as a sum of the binomial and trinomial coefficients, the general quintonomial coefficient as a sum of the binomial and quadrinomial coefficients, and gives a general determination of the coefficients of the expansion of an

Khaled Qazaqzeh

A p-periodic 3-manifold is a 3-manifold that admits a Z_{p}-action whose fixed point set is a circle. We give a congruence relates the quantum invariant of a p-periodic 3-manifold associated to any modular category over an integrally closed ground ring and the corresponding quantum invariant of its orbit space.

G. A. Quznetsov

The propositional logic is generalized on the real numbers field. the logical function with all properties of the classical probability function is obtained. The logical analog of the Bernoulli independent tests scheme is constructed. The logical analog of the Large Number Law is deduced from properties of these functions. The logical analog of thd condition

Alexander E. Holroyd, Yuval Peres

Let Πbe an ergodic simple point process on R^d and let Π^* be its Palm version. Thorisson [Ann. Probab. 24 (1996) 2057-2064] proved that there exists a shift coupling of Πand Π^*; that is, one can select a (random) point Y of Πsuch that translating Πby -Y yields a configuration whose law is that of Π^*. We construct shift couplings in which Y and Π^* are fun

W. Chagas-Filho

We show how an induced invariance of the massless particle action can be used to construct an extension of the Heisenberg canonical commutation relations in a non-commutative space-time.

Naoyuki Kawahara, Jun Nishimura

The large N reduction is an equivalence between large N gauge theories and matrix models discovered by Eguchi and Kawai in the early 80s. In particular the continuum version of the quenched Eguchi-Kawai model may be useful in studying supersymmetric and/or chiral gauge theories nonperturbatively. We apply this idea to matrix quantum mechanics, which is relev

N. G. Antoniou, Y. F. Contoyiannis, F. K. Diakonos, G. Mavromanolakis

A detailed study of correlated scalars, produced in collisions of nuclei and associated with the $σ$-field fluctuations, $(δσ)^2= < σ^2 >$, at the QCD critical point (critical fluctuations), is performed on the basis of a critical event generator (Critical Monte-Carlo) developed in our previous work. The aim of this analysis is to reveal suitable observables

D. Djukanovic, M. R. Schindler, J. Gegelia, S. Scherer

Quantum electrodynamics for $ρ$ mesons is considered. It is shown that, at tree level, the value of the gyromagnetic ratio of the $ρ^+$ is fixed to 2 in a self-consistent effective quantum field theory. Further, the mixing parameter of the photon and the neutral vector meson is equal to the ratio of electromagnetic and strong couplings, leading to the mass d

K. -I. Kubo, K. Suzuki

We discuss interplay of the scalar and vector diquarks which decide the characteristics of the spin polarization as functions of $p_T$ and $x_F$ in the wide kinematical range. We demonstrate a significant effect of quark masses on the pair-creation probabilities from vacuum in $pp \to Σ^- X$ and $γp \to ΛX$ collisions, and also a remarkable correction induce

Oscar Vives

We present a new mechanism to explain naturally and through a common flavour symmetry the mildly hierarchical neutrino masses with large mixings and the hierarchical Yukawa matrices with small mixing angles. Although this mechanism is not linked to a particular flavour symmertry, it is particularly simple in the framework of a SU(3) flavour symmetry. In this

Justin Foley, K. Jimmy Juge, Alan O&#39;Cais, Mike Peardon

A new method for computing all elements of the lattice quark propagator is proposed. The method combines the spectral decomposition of the propagator, computing the lowest eigenmodes exactly, with noisy estimators which are &#39;diluted&#39;, i.e. taken to have support only on a subset of time, space, spin or colour. We find that the errors are dramatically