December 2002 arXiv papers — page 16

Roberta Paladini, Rod Davies, Gianfranco DeZotti

HII regions are known to contribute to the so-called thin layer of the diffuse Warm Ionized Gas. In order to constrain this contribution, we reconstruct the 3-D distribution of the sources. A detailed spatial analysis of the largest up-to-date sample of HII regions is presented.

John N. Bahcall, M. C. Gonzalez-Garcia, C. Penya-Garay

We show that solar neutrino experiments set an upper limit of 7.8% (7.3% including the recent KamLAND measurements) to the fraction of energy that the Sun produces via the CNO fusion cycle, which is an order of magnitude improvement upon the previous limit. New experiments are required to detect CNO neutrinos corresponding to the 1.5% of the solar luminosity

Leonard S. Kisslinger

Possible CMBR correlations are estimated with a model in which a Hubble-size magnetic wall is formed during the QCD chiral phase transition. Measurable polarization correlations are found for l greater than 1000. Metric perturbations from the wall were found to give rise to observable correlations.

Vitor Cardoso, Oscar J. C. Dias, Jose' P. S. Lemos

Gravitational wave solutions to Einstein's equations and their generation are examined in D-dimensional flat spacetimes. First the plane wave solutions are analyzed; then the wave generation is studied with the solution for the metric tensor being obtained with the help of retarded D-dimensional Green's function. Due to the difficulties in handling t

A. Kiss, P. Fazekas

We examine trivalent Pr crystal field models with near-degeneracy of the two lowest crystal field levels, where interaction-induced quadrupolar and dipolar moments are as important as the permanent moments of the crystal field ground state. We find that the Gamma1-Gamma4 level scheme yields a successful description of the antiferroquadrupolar ordering of PrF

J. Matulewski, A. Raczynski, J. Zaremba

Photodetachment in ultrastrong laser field in two spatial dimensions is investigated numerically. The problem of an adiabatic stabilization is discussed, in particular it is shown that a quick drift in the direction of the electric field and a magnetic drift cannot be avoided simultaneously. A qualitative behavior of the packet for a short-range binding pote

P. Markos, C. M. Soukoulis

We analyze the transmission and reflection of the electromagnetic wave calculated from transfer matrix simulations of periodic arrangements of thin metallic wires. The effective permittivity and the absorption is determined. Their dependence on the wire thickness and the conductance of the metallic wires is studied. The cutoff frequency or effective plasma f

I. V. Dobrovolska, R. S. Tutik

The explicit semiclassical treatment of logarithmic perturbation theory for the bound-state problem within the framework of the radial Klein-Gordon equation with attractive real-analytic screened Coulomb potentials, contained time-component of a Lorentz four-vector and a Lorentz-scalar term, is developed. Based upon $\hbar$-expansions and suitable quantizati

Kazuyuki Fujii

In this paper we consider some (generalized) models which deal with n--level atom interacting with a single radiation mode and study a general structure of Rabi floppings of these generalized ones in the strong coupling regime. To solve these models we introduce multi cat states of Schr{\" o}dinger in our terminology and extend the result in (quant--ph/0

Y. Kanada-En'yo

Shape coexistence problems in N=14 isotones are studied with a microscopic method of antisymmetrized molecular dynamics. The present calculations reproduce features of deformation in 28Si, and predict possible shape coexistence of neutron density in neutron-rich nuclei(19B and 24Ne). We also systematically study the structures of the ground and excited state

S. S. Moskaliuk

In this article a group-theoretical aspect of the method of dimensional reduction is presented. Then, on the base of symmetry analysis of an anisotropic space geometrical description of dimensional reduction of equations for vector massless field is given. Formula for calculating components of the energy-momentum tensor from the variables of the field factor

Marco Zunino

We provide an analog of the Drinfeld quantum double construction in the context of crossed Hopf group coalgebras introduced by Turaev. We prove that, provided the base group is finite, the double of a semisimple crossed Hopf group coalgebra is both modular and unimodular.

M. B. Voloshin

The precise knowledge of the onset of the cross section $σ(e^+e^- \to τ^+τ^-)$ at the threshold is necessary for improving the accuracy of determination of the $τ$ mass from the threshold measurements. The QED radiative corrections of relative order $α$ and $α^2$, additional to the well known Coulomb factor, are considered in the threshold region. The correc

Michael E. Peskin

I describe the picture by which supersymmetry--the possible symmetry of Nature that converts fermions to bosons and vice versa--accounts for the next stage of physics beyond the Standard Model. I then survey the future experimental program implied by this theory, in which the spectrum of particles associated with supersymmetry will be determined with precisi

Geoffrey T. Bodwin

I summarize the current status of the comparison between experiment and the predictions of the NRQCD factorization approach to quarkonium decay and production. I also present the results of some recent calculations and theoretical developments in the NRQCD factorization approach.

David Rideout

The Causal Set approach to quantum gravity asserts that spacetime, at its smallest length scale, has a discrete structure. This discrete structure takes the form of a locally finite order relation, where the order, corresponding with the macroscopic notion of spacetime causality, is taken to be a fundamental aspect of nature. After an introduction to the Cau

K. V. Kavokin

The symmetry of exchange interaction of charge carriers in semiconductor nanostructures (quantum wells and quantum dots) is analysed. It is shown that the exchange Hamiltonian of two particles belonging to the same energy band can be universally expressed via pseudospin operators of the particles. The relative strength of the anisotropic exchange interaction

Walter Kob

Lecture notes for LES HOUCHES 2002 SUMMER SCHOOL - SESSION LXXVII on SLOW RELAXATIONS AND NONEQUILIBRIUM DYNAMICS IN CONDENSED MATTER; Les Houches: July 1-26, 2002

W. Florek

The group-theoretical classification of multiparticle states(pairs of particles and charged excitons X^+-) is based on considerations of products of irreducible projective representations of the two-dimensional translation group. The states of a pair particle-antiparticle are non-degenerate, whereas, for a given Born-von Karman period N, degeneracy of pair s

W. Florek, G. Kamieniarz, A. Caramico D'Auria, U. Esposito

A finite spin system invariant under a symmetry group G is a very illustrative example of the finite group action on a set of mappings f:X->Y. In the case of spin systems X is a set of spin carriers and Y contains 2s+1 z-components -s<=m<=s for a given spin number s. Orbits and stabilizers are used as additional indices of the symmetry adapted basis. Their m

Bernhard A. Wolf

In part I of this contribution we have reported how the Flory-Huggins interaction parameter chi can be modeled as a function of chain length within the composition range of pair interaction between the macromolecules by means of the three parameters alpha, zeta and lambda. This contribution presents the extension of the approach to arbitrary volume fractions

Maria Bercea, Maria Cazacu, Bernhard A. Wolf

This is the first of two parts investigating the Flory-Huggins interaction parameter chi as a function of composition and chain length. Part I encompasses experimental and theoretical work. The former comprises the synthesis of poly(dimethylsiloxane)s with different molar mass and the measurements of their second osmotic virial coefficients in solvents of di

Salvatore Miccichè, Giovanni Bonanno, Fabrizio Lillo, Rosario N. Mantegna

We investigate the time series of the degree of minimum spanning trees obtained by using a correlation based clustering procedure which is starting from (i) asset return and (ii) volatility time series. The minimum spanning tree is obtained at different times by computing correlation among time series over a time window of fixed length $T$. We find that the

Grzegorz Litak

Using the negative U Hubbard model we analyze normal state properties of a superconductor. In this model there exists a characteristic pairing temperature T_P above a superconducting critical temperature. Below T_P electrons start to form incoherent pairs. The fluctuations in charge and phase are precursors of charge density wave and superconductivity phases

Andrew R. Zentner, James S. Bullock

In this proceeding, we present the results of a semi-analytic study of CDM substructure as a function of the primordial power spectrum. We apply our method to several tilted models in the LCDM framework with n=0.85-1.1, sigma_8=0.65-1.2 when COBE normalized. We also study a more extreme, warm dark matter-like spectrum that is sharply truncated below a scale

Francesco Miniati

We address the role of gamma-ray astronomy in the investigation of nonthermal processes in the large scale structure of the universe. Based on EGRET upper limits on nearby galaxy clusters (GCs) we constrain the acceleration efficiency of CR electrons at intergalactic shocks to <=1 % than the shock ram pressure. That implies a contribution to the cosmic gamma

Charles Beichman

The goal of finding and characterizing habitable planets in other solar systems represents one of humanity&#39;s greatest scientific challenges. NASA and ESA have initiated studies of missions that could accomplish this goal within the next ten years. What precursor knowledge do we need before we can initiate such a mission? How large should the first steps

Charles Beichman

Over two hundred years ago Capt. James Cook sailed up Whitsunday Passage, just a few miles where we now sit, on a voyage of astronomical observation and discovery that remains an inspiration to us all. Since the prospects of our visiting planets beyond our solar system are slim, we will have to content ourselves with searching for life using remote sensing,

Peter Erwin, Alister W. Graham, Nicola Caon

We demonstrate a strong correlation between supermassive black hole (SMBH) mass and the global structure of ellipticals and bulges: more centrally concentrated bulges and ellipticals (higher Sersic index $n$) host higher-mass black holes. This correlation is as good as that previously found between SMBH mass and central velocity dispersion, with comparable s

A. Coley, R. Milson, N. Pelavas, V. Pravda

We shall investigate $D$-dimensional Lorentzian spacetimes in which all of the scalar invariants constructed from the Riemann tensor and its covariant derivatives are zero. These spacetimes are higher-dimensional generalizations of $D$-dimensional pp-wave spacetimes, which have been of interest recently in the context of string theory in curved backgrounds i

C. A. Bertulani, V. Zelevinsky

In light of a new experiment which claims a positive identification, we discuss the possible existence of the tetraneutron. We explore a novel model based on a dineutron-dineutron molecule. We show that this model is not able to explain the tetraneutron as a bound state, in agreement with other theoretical models already discussed in the literature.

George Siopsis

In the Penrose limit, AdS*S space turns into a Cahen-Wallach (CW) space whose Killing vectors satisfy a Heisenberg algebra. This algebra is mapped onto the holographic screen on the boundary of AdS. I show that the Heisenberg algebra on the boundary of AdS may be obtained directly from the CW space by appropriately constraining the states defined on it. The

A. V. Tarakanov, A. V. Reichel, S. A. Smolyansky, S. M. Schmidt

We study particle - antiparticle pair production under action of a strong time dependent space homogeneous electric field at the presence of a collinear constant magnetic field. We derive the kinetic equation for a such field configuration for fermions and bosons in the framework of the Schwinger mechanism of vacuum tunneling. We show the enhancement of pair

Miklos Abert, Balint Virag

We explore the structure of the p-adic automorphism group Gamma of the infinite rooted regular tree. We determine the asymptotic order of a typical element, answering an old question of Turan. We initiate the study of a general dimension theory of groups acting on rooted trees. We describe the relationship between dimension and other properties of groups suc

Panagiota Kanti, John March-Russell

The production of black holes in extra-dimensional brane-world theories can lead to detectable signals via the Hawking evaporation of the black hole to brane-localised Standard Model modes. We calculate, as a function of partial wave number and number of toroidally compactified extra dimensions, the leading correction to the energy spectrum of such Hawking r

W. T. Lu, F. Y. Wu

We establish new product identities involving the $q$-analogue of the Fibonacci numbers. We show that the identities lead to alternate expressions of generating functions for close-packed dimers on non-orientable surfaces.

Artem M. Dudarev, Roberto B. Diener, Biao Wu, Mark G. Raizen

We study the preparation and manipulation of states involving a small number of interacting particles. By controlling the splitting and fusing of potential wells, we show how to interconvert Mott-insulator-like and trapped BEC-like states. We also discuss the generation of &#34;Schrödinger cat&#34; states by splitting a microtrap and taking into practical co

Tamar Friedmann, Herman Verlinde

We study Schwinger pair creation of charged Kaluza-Klein particles from a static KK electric field. We find that the gravitational backreaction of the electric field on the geometry - which is incorporated via the electric KK Melvin solution - prevents the electrostatic potential from overcoming the rest mass of the KK particles, thus impeding the tunneling

D. M. Ghilencea, S. Groot Nibbelink

An effective field theory approach is introduced to compute one-loop radiative corrections to the gauge couplings due to Kaluza-Klein states associated with a two-torus compactification. The results are compared with those of the string in the field theory ``limit&#39;&#39; alpha&#39;-> 0. The whole U and the leading T moduli dependence of the gauge dependen

Edmundo M. Monte, M. D. Maia

The topological structure of Schwarzschild&#39;s space-time and its maximal analytic extension are investigated in context of brane-worlds. Using the embedding coordinates, these geometries are seen as different states of the evolution of a single brane-world. Comparing the topologies and the embeddings it is shown that this evolution must be followed by a s

P. Barbeau, J. I. Collar, J. Miyamoto, I. Shipsey

The detection of low energy neutrinos ($<$ few tens of MeV) via coherent nuclear scattering remains a holy grail of sorts in neutrino physics. This uncontroversial mode of interaction is expected to profit from a sizeable increase in cross section proportional to neutron number squared in the target nucleus, an advantageous feature in view of the small proba

V. V. Fernández, A. M. Moya, W. A. Rodrigues

Let $V$ be a $n$-dimensional real vector space. In this paper we introduce the concept of \emph{euclidean} Clifford algebra $\mathcal{C\ell}(V,G_{E})$ for a given euclidean structure on $V,$ i.e., a pair $(V,G_{E})$ where $G_{E}$ is a euclidean metric for $V$ (also called an euclidean scalar product). Our construction of $\mathcal{C\ell}(V,G_{E})$ has been d

David C. Dunbar, Nicolaus W. P. Turner

We calculate one-loop scattering amplitudes for gravitons and two-forms in dimensions greater than four. The string based Kawai-Lewellen-Tye relationships allow gravitons and two-forms to be treated in a unified manner. We use the results to determine the ultra-violet infinities present in these amplitudes and show how these determine the renormalised one-lo

Amir H. Rezaeian, Niels R. Walet

Renormalization of Hamiltonian field theory is usually a rather painful algebraic or numerical exercise. By combining a method based on the coupled cluster method, analysed in detail by Suzuki and Okamoto, with a Wilsonian approach to renormalization, we show that a powerful and elegant method exist to solve such problems. The method is in principle non-pert

Ujjal Debnath, Subenoy Chakraborty

We investigate the end state of the gravitational collapse of an inhomogeneous dust cloud in higher dimensional space-time. The naked singularities are shown to be developing as the final outcome of non-marginally bound collapse. The naked singularities are found to be gravitationally strong in the sense of Tipler .

Zhou Bang-Rong

We have proven the general relations between the gap equations obeyed by dynamical fermion mass and corresponding effective potentials at finite temperature and chemical potential in D dimensional four-fermion interaction models. This gives an easy approach to get effective potentials directly from the gap equations. We find out explicit expressions for the

Damian H. Zanette, Marcelo A. Montemurro

We show that a gas thermometer in contact with a stationary classical system out of thermal (Boltzmann) equilibrium evolves, under very general conditions, towards a state characterized by a Levy velocity distribution. Our approach is based on a kinetic-like equation that applies to a wide class of models for the system-thermometer interaction. The results c

J. M. Gracia-Bondia, S. Lazzarini

The Epstein--Glaser type T-subtraction introduced by one of the authors in a previous paper is extended to the Lorentz invariant framework. The advantage of using our subtraction instead of Epstein and Glaser&#39;s standard W-subtraction method is especially important when working in Minkowski space, as then the counterterms necessary to keep Lorentz invaria

Matthew A. Buican, Valery A. Khoze, Wolfgang Ochs

We discuss the predictions of perturbative QCD for angular flows of final state particles in two and three jet events including their cms energy and jet resolution (y_{cut}) dependence. The simple analytical formulae for gluon bremsstrahlung from primary partons, modified for gluon cascading, reproduce the main features of the experimental data well. For y_{

Thibault Damour, Ian I. Kogan, Antonios Papazoglou

We explore spherically symmetric stationary solutions, generated by ``stars&#39;&#39; with regular interiors, in purely massive gravity. We reexamine the claim that the resummation of non-linear effects can cure, in a domain near the source, the discontinuity exhibited by the linearized theory as the mass m of the graviton tends to zero. First, we find analy

UKQCD Collaboration, C. McNeile, C. Michael

We explore the decay of a vector meson to two pseudoscalar mesons on the lattice with $N_f=2$ flavours of sea quark. Although we are working with quark masses that do not allow a physical decay, we show how the transition rate can be evaluated from the amplitude for $ρ\to ππ$ and from the annihilation component of $ππ\to ππ$. We explore the decay amplitude f

J. Schweizer

We construct the explicit one-loop functional of chiral perturbation theory for two light flavours, including virtual photons. We stick to contributions where 1 or 2 mesons and at most one photon are running in the loops. With the explicit functional at hand, the evaluation of the relevant Green functions boils down to performing traces over the flavour matr

K. D. Machado, J. C. de Lima, T. A. Grandi, C. E. M. de Campos

The aging of a nanocrystalline equiatomic ZnSe alloy produced by mechanical alloying was investigated using X-ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques. The measured XRD patterns showed that Se atoms located at interfacial component migrated with aging giving raise to a crystalline selenium (c-Se) phase. DSC spectra of heat

N. C. Hastings

We report a precise determination of the B0-B0bar mixing parameter Delta-m_d based on the time evolution of same-sign and opposite-sign dilepton yields in Upsilon(4S) decays. Data were collected with the Belle detector at KEKB. Using data samples of 29.4 1/fb recorded at the Upsilon(4S) resonance and 3.0 1/fb recorded at an energy 60MeV below the resonance,

Hyeong-Chan Kim, Jae Hyung Yee

We present a variational method which uses a quartic exponential function as a trial wave-function to describe time-dependent quantum mechanical systems. We introduce a new physical variable $y$ which is appropriate to describe the shape of wave-packet, and calculate the effective action as a function of both the dispersion $\sqrt{< \hat{q}^2>}$ and $y$. The

H. Fritzsch

Astrophysical indications that the fine structure constant has undergone a small time variation during the cosmological evolution are discussed within the framework of the standard model of the electroweak and strong interactions and of grand unification. A variation of the electromagnetic coupling constant could either be generated by a corresponding time v

A. Y. Abul-Magd, H. L. Harney, M. H. Simbel, H. A. Weidenmueller

Using all the available empirical information, we analyze the spacing distributions of low-lying 2-plus levels of even-even nuclei. To obtain statistically relevant samples, the nuclei are grouped into classes defined by the ratio R4/2 of the excitation energies of the first 4-plus and 2-plus levels. This ratio serves as a measure of collectivity in nuclei.

Li-Xin Li, Jeremiah P. Ostriker

Based on observed rotation curves of galaxies and theoretical simulations of dark matter halos, there are reasons for believing that at least three different types of dark matter halos exist in the Universe classified by their masses M and the inner slope of mass density -α: Population A (galaxies): 10^{10} h^{-1} M_\odot < M < 2 \times 10^{13} h^{-1} M_\odo

Jason Semitecolos

This paper has been withdrawn by the author

Geoffrey T. Bodwin, Eric Braaten, Jungil Lee

Recent measurements by the Belle Collaboration of the exclusive production of two charmonia in e^+ e^- annihilation differ substantially from theoretical predictions. We suggest that a significant part of the discrepancy can be explained by the process e^+ e^- -> J/psi + J/psi. Because the J/psi + J/psi production process can proceed through fragmentation of

A. Achucarro, J. Urrestilla

We point out a problem with the stability of composite (global-magnetic) monopoles recently proposed by J. Spinelly, U. de Freitas and E.R. Bezerra de Mello [Phys. Rev. D66, 024018 (2002)].

W. Philipp, K. Hess

In this paper we give a detailed and simplified version of our original mathematical model published first in the Proceedings of the National Academy of Science. We hope that this will clarify some misinterpretations of our original paper.

Caslav Brukner, Anton Zeilinger

Niels Bohr wrote: &#34;There is no quantum world. There is only an abstract quantum physical description. It is wrong to think that the task of physics is to find out how Nature is. Physics concerns what we can say about Nature.&#34; In an analogous way, von Weizsaecker suggested that the notion of the elementary alternative, the &#34;Ur&#34;, should play a

Stefan Keppeler

We derive explicit semiclassical quantisation conditions for the Dirac and Pauli equations. We show that the spin degree of freedom yields a contribution which is of the same order of magnitude as the Maslov correction in Einstein-Brillouin-Keller quantisation. In order to obtain this result a generalisation of the notion of integrability for a certain skew

M. S. Safronova, Carl J. Williams, Charles W. Clark

The fast phase gate scheme, in which the qubits are atoms confined in sites of an optical lattice, and gate operations are mediated by excitation of Rydberg states, was proposed by Jaksch et al. Phys. Rev. Lett. 85, 2208 (2000). A potential source of decoherence in this system derives from motional heating, which occurs if the ground and Rydberg states of th

B. G. Sidharth

In this note we consider a variable $G$ cosmology which is consistent with observation and which had successfully predicted an ever expanding accelerating universe. It is shown that the observed shortening of the orbital periods of binary pulsars is also in good agreement with this model.

Ilya V. Shadrivov, Andrey A. Sukhorukov, Yuri S. Kivshar

We analyze transmission of a layered photonic structure (a one-dimensional photonic crystal) consisting of alternating slabs of two materials with positive and negative refractive index. For the periodic structure with zero averaged refractive index, we demonstrate a number of unique properties of the beam transmission observed in strong beam modification an

Roberto Assumpcao

Classical, Quantum, Relativistic and Statistical: the four branches of mechanics. However, the Quattro Donna of Physics disagree even about the entities that are supposed to be fundamental, such as space, matter and time. In order to search for an union, this contribution considers Indeterminacy in a Classical context and takes a path based on a division tha

S. Nakamura, T. Sato, S. Ando, T. -S. Park

In interpreting the SNO experiments, accurate estimates of the νd reaction cross sections are of great importance. In our recent work, we have improved our previous calculation by updating some of its inputs and by incorporating the results of a recent effective-field-theoretical calculation. The new cross sections are slightly (\sim 1%) larger than the prev

A. Covello, L. Coraggio, A. Gargano, N. Itaco

We report here on a shell-model study of nuclei close to doubly magic 132Sn and 100Sn focusing attention on particle-hole multiplets. In our study we make use of realistic effective interactions derived from the CD-Bonn nucleon-nucleon potential. We present results for the four nuclei 132Sb, 130Sb, 102In and 98Ag. Comparison shows that the calculated results

I. Bednarek, A. Brzezina, R. Manka, M. Zastawny-Kubica

Using the Relativistic Mean Field Theory (RMF) it is shown that different proton fraction which is directly connected with the neutron excess and with the asymmetry of the system affects proto-neutron stars parameters and changes their composition. The obtained form of the equation of state allows to construct the mass-radius relations and shows that the inc

S. Aronson, K. Assamagan, H. Gordon, M. Leite

The ATLAS collaboration has significant interest in the physics of ultra-relativistic heavy ion collisions. We submitted a Letter of Intent to the United States Department of Energy in March 2002. The following document is a slightly modified version of that LOI. More details are available at: http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/SM/ions

Johannes P. Wessels

In this talk latest results from the analysis of e+e- pairs emitted in Pb+Au collisions at 40 AGeV/c and a combined analysis of all data available at 158 AGeV/c are presented. The enhancement of low-mass e+e- pairs (m_ee>0.2 GeV/c^2) with respect to the expected yield from hadron decays first reported at 158 AGeV/c is also found at 40 AGeV/c and is even larg

Jianke Yang, Dmitry E. Pelinovsky

We study both analytically and numerically the existence, uniqueness, and stability of vortex and dipole vector solitons in a saturable nonlinear medium in (2+1) dimensions. We construct perturbation series expansions for the vortex and dipole vector solitons near the bifurcation point where the vortex and dipole components are small. We show that both solut

Sandro Wimberger, Italo Guarneri, Shmuel Fishman

The quantum resonances occurring with delta-kicked atoms when the kicking period is an integer multiple of the half-Talbot time are analyzed in detail. Exact results about the momentum distribution at exact resonance are established, both in the case of totally coherent dynamics and in the case when decoherence is induced by Spontaneous Emission. A descripti

Omar Mustafa

Fernandez Comment [1] on our pseudo-perturbative shifted-l expansion technique [2,3] is either unfounded or ambiguous.

Victor Tapia

We develop a method to construct algebraic invariants for hypermatrices. We then construct hyperdeterminants and exhibit a generalization of the Cayley-Hamilton theorem for hypermatrices.

Jeffrey F. Brock, Kenneth W. Bromberg

The density conjecture of Bers, Sullivan and Thurston predicts that each complete hyperbolic 3-manifold M with finitely generated fundamental group is an algebraic limit of geometrically finite hyperbolic 3-manifolds. We prove that the conjecture obtains for each complete hyperbolic 3-manifold with no cusps and incompressible ends.

Francois Ebobisse, Marcello Ponsiglione

In this paper we study the asymptotic behaviour of the solutions of some minimization problems for integral functionals with convex integrands, in two-dimensional domains with cracks, under perturbations of the cracks in the Hausdorff metric. In the first part of the paper, we examine conditions for the stability of the minimum problem via duality arguments

John J. Benedetto, Wojciech Czaja, Andrei Ya. Maltsev

In this paper we extend the Balian--Low theorem, which is a version of the uncertainty principle for Gabor (Weyl--Heisenberg) systems, to functions of several variables. In particular, we first prove the Balian--Low theorem for arbitrary quadratic forms. Then we generalize further and prove the Balian--Low theorem for differential operators associated with a

Andreas Hartmann, Xavier Massaneda, Artur Nicolau

We give an analytic characterisation of the interpolating sequences for the Nevanlinna and Smirnov classes. From this we deduce a necessary and a sufficient geometric condition, both expressed in terms of a certain non-tangential maximal function associated to the sequence. Some examples show that the gap between the necessary and the sufficient condition ca

Steven Dale Cutkosky

Suppose that f is a dominant morphism from a k-variety X to a k-variety Y, where k is a field of characteristic 0 and v is a valuation of the function field k(X). We allow v to be an arbitary valuation, so it may not be discrete. We prove that there exist sequences of blowups of nonsingular subvarieties from X&#39; to X and from Y&#39; to Y such that X&#39;,

Volker Kaibel, Günter M. Ziegler

We discuss the problem to count, or, more modestly, to estimate the number f(m,n) of unimodular triangulations of the planar grid of size $m\times n$. Among other tools, we employ recursions that allow one to compute the (huge) number of triangulations for small m and rather large n by dynamic programming; we show that this computation can be done in polynom

Ernesto Lupercio, Bernardo Uribe

In this paper we define and study the &#34;ghost loop orbifold&#34; of an orbifold $X$ consisting of those loops that remain constant in the coarse moduli space of $X$. We construct a configuration space model for the ghost loop orbifold using an idea of G. Segal. From this we exhibit the relation between the Hochschild and cyclic homologies of the inertia o

Terence Tao

Recently Wolff obtained a sharp $L^2$ bilinear restriction theorem for bounded subsets of the cone in general dimension. Here we adapt the argument of Wolff to also handle subsets of ``elliptic surfaces&#39;&#39; such as paraboloids and spheres. Except for an endpoint, this answers a conjecture of Machedon and Klainerman, and also improves upon the known res

F. Javier Thayer

Suppose B is an ultraproduct of finite dimensional C^\ast-algebras. We consider mapping and injectability properties for separable C^\ast-algebras into B. In the case of approximately finite C^\ast-algebras, we obtain a classification of these mappings up to inner conjugacy. Using a Theorem of Voiculescu, we show that for nuclear C^\ast-algebras injectabilit

R. Parthasarathy, K. S. Viswanathan

A non-trivial q-deformation of the fermionic oscillator proposed by us in 1991 is recalled in view of the result of the paper cited in the title.

Paolo Di Vecchia

We use fractional and wrapped branes to describe perturbative and nonperturbative properties of the gauge theories living on their worldvolume. (Talk given at the 35th International Symposium Ahrenshoop on the Theory of Elementary Particles, Wernsdorf, August 26-30, 2002.)

Pasquale Calabrese, Andrea Pelissetto, Paolo Rossi, Ettore Vicari

We discuss several examples of three-dimensional critical phenomena that can be described by Landau-Ginzburg-Wilson $ϕ^4$ theories. We present an overview of field-theoretical results obtained from the analysis of high-order perturbative series in the frameworks of the $ε$ and of the fixed-dimension d=3 expansions. In particular, we discuss the stability of

Nicolás E. Grandi, Adrián R. Lugo

We obtain a $\frac 14$-supersymmetric 6-brane solution of IIA Supergravity by T-dualizing the supertube recently found. The resulting $C_{\it 1}$ electric charge is related to the original $D0$-brane charge. The uplifted solution to eleven dimensions results to be a purely geometrical configuration, which can be interpreted as a bound state of a Taub-NUT spa

Vladimir Dotsenko, Jesper Lykke Jacobsen, Raoul Santachiara

A parafermionic conformal theory with the symmetry Z_5 is constructed, based on the second solution of Fateev-Zamolodchikov for the corresponding parafermionic chiral algebra. The primary operators of the theory, which are the singlet, doublet 1, doublet 2, and disorder operators, are found to be accommodated by the weight lattice of the classical Lie algebr

Alexander A. Osipov, Brigitte Hiller

The method which allows for asymptotic expansion of the one-loop effective action W=ln det A is formulated. The positively defined elliptic operator A= U + M^2 depends on the external classical fields taking values in the Lie algebra of the internal symmetry group G. Unlike the standard method of Schwinger - DeWitt, the more general case with the nondegenera

J. Reuter

We investigate the algebraic structure of supersymmetric Ward- and Slavnov-Taylor identities (STI) in field theories with global supersymmetry. We develop diagrammatical methods for STI in supersymmetric gauge theories within a generalized BRST formalism. These identities are used as consistency checks for the implementation of phenomenological supersymmetri

L. Mersini, M. Bastero-Gil

The problem of dark energy arises due to its self-gravitating properties. Therefore explaining vacuum energy may become a question for the realm of quantum gravity, that can be addressed within string theory context. In this talk I concentrate on a recent, string-inspired model, that relies on nonlinear physics of short-distance perturbation modes, for expla

Stephon H. S. Alexander

We generalize the Brane Gas Cosmological Scenario to M-theory degrees of freedom, namely $M5$ and $M2$ branes. Without brane intersections, the Brandenberger Vafa(BV) arguments applied to M-theory degrees of freedom generically predict a large 6 dimensional spacetime. We show that intersections of $M5$ and $M2$ branes can instead lead to a large 4 dimensiona

Marianna Larosa

I review the basic features of four dimensional Z_2 x Z_2 (shift) orientifolds with internal magnetic fields, describing two examples with N=1 supersymmetry. As in the corresponding six-dimensional examples, D9-branes magnetized along four internal directions can mimic D5-branes, even in presence of multiplets of image branes localized on different fixed tor

A. H. Mueller, D. T. Son

We consider a system made up of exictations of a neutral scalar field, ϕ, having a λϕ^4 interaction term. Starting from an ensemble where the occupation number f is large, but λf is small, we develop a classical field theory description of the evolution of the system toward equilibrium. A Boltzmann equation naturally emerges in this description and we show b

Harald Fritzsch, Zhi-zhong Xing

We show that the four-zero texture of Hermitian quark mass matrices can survive current experimental tests: it is able to yield sufficiently large predictions for the flavor mixing parameter $|V_{ub}/V_{cb}|$ and the CP-violating parameter $\sin 2β$, without fine-tuning of the input values of quark masses, provided the (2,2), (2,3) and (3,3) elements of up a

Heinrich Päs, Thomas J. Weiler

The determination of absolute neutrino masses is crucial for the understanding of theories underlying the standard model, such as SUSY. We review the experimental prospects to determine absolute neutrino masses and the correlations among approaches, using the Delta m^2&#39;s inferred from neutrino oscillation experiments and assuming a three neutrino Univers

Ph. Boucaud, F. De Soto, A. Le Yaouanc, J. P. Leroy

We present a study of $α_{MOM}(p)$ at small p computed from the lattice. It shows a dramatic $\propto p^4$ law which can be understood within an instanton liquid model. In this framework the prefactor gives a direct measure of the instanton density in thermalised configurations. A preliminary result for this density is 5.27(4) fm^{-4}.