February 1998 arXiv papers — page 15

Walter LoFaro

The nth relative Kauffman bracket skein modules are defined and two theorems are given relating them to the Kauffman bracket skein module of a 3-manifold. The first theorem covers the case when the 3-manifold is split along a separating closed orientable surface and the second theorem addresses the case when the surface is nonseparating.

Sijong Kwak

Castelnuovo-Mumford regularity is an important invariant of projective algebraic varieties. A well known conjecture due to Eisenbud and Goto gives a bound for regularity in terms of the codimension and degree,i.e., Castelnuovo-Mumford regularity of a given variety $X$ is less than or equal to $deg(X)-codim(X)+1$. This regularity conjecture (including classif

Thomas Peternell

We prove the existence of a Mori contraction on a compact Kaehler threefold whose canonical bundle is (analytically) not nef if the threefold can be approximated by projective threefolds or if the algebraic dimension is 2.

M. Nikbakht-Tehrani

Using the homogeneous coordinate ring construction of a toric variety IP defined by a complete simplicial fan and the methods of local cohomology theory we develop a framework for the calculation of cohomology groups H^{*}(IP, O(p)) of twisting sheaves O(p) on IP.

Alexander Fel'shtyn, Richard Hill

In this paper we prove trace formulae for the Reidemeister number of a group endomorphism. This result implies the rationality of the Reidemeister zeta function in the following cases: the group is a direct product of a finite group and a finitely generated Abelian group; the group is finitely generated, nilpotent and torsion free. We continue to study analy

V. Grassi, R. A. Leo, G. Soliani, L. Solombrino

A systematic analysis of a continuous version of a binomial lattice, containing a real parameter $γ$ and covering the Toda field equation as $γ\to\infty$, is carried out in the framework of group theory. The symmetry algebra of the equation is derived. Reductions by one-dimensional and two-dimensional subalgebras of the symmetry algebra and their correspondi

J. Ambjorn, K. N. Anagnostopoulos, J. Jurkiewicz, C. Kristjansen

We show that the ``time'' t_s defined via spin clusters in the Ising model coupled to 2d gravity leads to a fractal dimension d_h(s) = 6 of space-time at the critical point, as advocated by Ishibashi and Kawai. In the unmagnetized phase, however, this definition of Hausdorff dimension breaks down. Numerical measurements are consistent with these resu

Brandon Carter

A general method of regularisation of classical self interaction in strings is extended from the electromagnetic case (for which it was originally developed) to the gravitation case, for which the result can also be represented as a renormalisation.

E. G. Floratos, G. K. Leontaris

In this letter we discuss the supersymmetry issue of the self dual supermembranes in (8+1) and (4+1)-dimensions. We find that all genuine solutions of the (8+1)-dimensional supermembrane, based on the exceptional group G_2, preserve one of the sixteen supersymmetries while all solutions in (4+1)-dimensions preserve eight of them.

R. H. Dalitz, Gary R. Goldstein

We have carried out Monte Carlo calculations on two sets of randomly generated QCD events due to $p\bar{p} \to t \bar{t}$ with top mass $m_t = 170$ GeV, one set leading to $e^+e^-$ or $e^{\pm}μ^{\mp}$ or $μ^+μ^-$ 2jets (dilepton) and the other leading to $e^{\pm}$ or $μ^{\pm}$ 4jets (unilepton) configurations, in order to test the likelihood methods we have

L. Burakovsky, T. Goldman

We show that only additivity of inverse Regge slopes is consistent with both the formal chiral limit m(n)\to 0 and the heavy quark limit M(Q)>>M(n), where n=u,d, and m,M are current and constituent quark masses, respectively.

Sangyong Jeon, Paul J. Ellis

An often used rule that the thermal correction to the self-energy is the thermal phase-space times the forward scattering amplitude from target particles is shown to be the leading term in an exact multiple scattering expansion. Starting from imaginary-time finite-temperature field theory, a rigorous expansion for the retarded self-energy is derived. The rel

J. Fleischer, M. Tentyukov

We present a review of the Bielefeld-Dubna activities on multiloop calculations.

M. Tentyukov, J. Fleischer

A C-program DIANA (DIagram ANAlyser) for the automation of Feynman diagram evaluations is presented.

A. Riotto

We discuss some recent developments made in the computation of the baryon asymmetry generated at the electroweak scale. We emphasize that the local number density asymmetries of the particles involved in supersymmetric electroweak baryogenesis must be described by a set of Quantum Boltzmann Equations. These diffusion equations automatically and self-consiste

D. Atkinson, J. C. R. Bloch

In a previous paper we have shown that in quantum chromodynamics the gluon propagator vanishes in the infrared limit, while the ghost propagator is more singular than a simple pole. These results were obtained after angular averaging, but in the current paper we go beyond this approximation and perform an exact calculation of the angular integrals. The power

Ning Wu

A gauge field model, which simultaneously has strict local gauge symmetry and massive gauge bosons, is discussed in this paper. The model has SU(N) gauge symmetry. In the limit $α\longrightarrow 0$, the gauge field model discussed in this paper will return to Yang-Mills gauge field model. The important meaning of this model is that, without Higgs mechanism,

H. V. Klapdor-Kleingrothaus

Nuclear double beta decay provides an extraordinarily broad potential to search for beyond Standard Model physics, probing already now the TeV scale, on which new physics should manifest itself. These possibilities are reviewed here. First, the results of present generation experiments are presented. The most sensitive one of them -- the Heidelberg-Moscow ex

E. B. McDaniel, J. W. P. Hsu

Using a near-field scanning optical microscope capable of quantitative polarimetry, we map the anisotropic strain fields associated with individual submicron defects near the fusion boundaries of SrTiO$_{3}$ bicrystals. Many defects exhibit unexpected spiral-shape strain patterns, whose handedness is believed to be linked to the bicrystal synthesis process.

R. Kotlyar, C. A. Stafford, S. Das Sarma

The ground state persistent current and electron addition spectrum in two-dimensional quantum dot arrays and one-dimensional quantum dot rings, pierced by an external magnetic flux, are investigated using the extended Hubbard model. The collective multidot problem is shown to map exactly into the strong field noninteracting finite-size Hofstadter butterfly p

M. E. Zhitomirsky, M. B. Walker

We calculate correction to the critical temperature of a dirty superconductor, which results from the local variations of the gap function near impurity sites. This correction is of the order of T_c/E_F and becomes important for short-coherence length superconductors. It generally reduces a pair-breaking effect. In s-wave superconductors small amounts of non

J. Stockburger, C. H. Mak

Current fluctuations in a dissipative two-state system have been studied using a novel quantum dynamics simulation method. After a transformation of the path integrals, the tunneling dynamics is computed by deterministic integration over the real-time paths under the influence of colored noise. The nature of the transition from coherent to incoherent dynamic

Avinash Singh, Prasenjit Sen

A formalism is developed to treat magnetic impurities in a Mott-Hubbard antiferromagnetic insulator within a representation involving multiple orbitals per site. Impurity scattering of magnons is found to be strong when the number of orbitals N' on impurity sites is different from the number N on host sites. The impurity-scattering-induced softening of m

Boaz Kol, Amnon Aharony

The diffusion limited aggregation model (DLA) and the more general dielectric breakdown model (DBM) are solved exactly in a two dimensional cylindrical geometry with periodic boundary conditions of width 2. Our approach follows the exact evolution of the growing interface, using the evolution matrix E, which is a temporal transfer matrix. The eigenvector of

Sanjeev Gautam, D. K. Shukla, Shelly Jain, N. Goyal

This paper reports conduction mechanism in a-\sbse over a wide range of temperature (238K to 338K) and frequency (5Hz to 100kHz). The d.c. conductivity measured as a function of temperature shows semiconducting behaviour with activation energy $Δ$E= 0.42 eV. Thermally induced changes in the electrical and dielectric properties of a-\sbse have been examined.

E. V. Thuneberg

Liquid 3He at low temperatures is an ideal substance to study because of its natural purity. The superfluid state, which appears at temperatures below 3 mK, has many unusual and exciting properties. These have extensively been studied experimentally, and the results are in many cases well understood theoretically using quasiclassical approximation. In this w

Benoit Gremaud, Dominique Delande

We calculate the photo-ionization cross-section from the ground state of the helium atom, using the complex rotation method and diagonalization of sparse matrices. This produces directly the positions and widths of the doubly excited 1Po resonances together with the photo-ionization cross-section. Our calculations up to the N=9 threshold are in perfect agree

Paul J. Green

We contrast measurements of composite optical and ultraviolet (UV) spectra constructed from samples of QSOs defined by their soft X-ray brightness. X-ray bright (XB) composites show stronger emission lines in general, but particularly from the narrow line region. The difference in the [OIII]/Hbeta ratio is particularly striking, and even more so when blended

J. F. Olive, D. Barret, L. Boirin, J. E. Grindlay

We report on the RXTE/PCA observation of the X-ray burster 1E1724-3045 located in the globular cluster Terzan 2. The persistent X-ray emission shows a high level of noise variability, the so-called High Frequency Noise (HFN) with a fractional Root Mean Squared (RMS) of about 25% in the 2E-3 - 40 Hz range. The strong HFN together with the hardness of its X-ra

Jules P. Halpern, Michael Eracleous, Karl Forster

New optical spectra of the original narrow-line quasar 1E 0449.4-1823 show that it now has broad emission lines of considerable strength, eliminating it as a "type 2 QSO" candidate. We suggest that the behavior of 1E 0449.4-1823 is the same as that of some Seyfert 1.8 and 1.9 galaxies, in which Goodrich attributed long-term variations of their broad

Stella Seitz, Peter Schneider

A new method for the reconstruction of the projected mass distribution of clusters of galaxies from the image distortion of background galaxies is discussed. This method is essentially equivalent to the one we developed previously, i.e., the noise-filtering method, but has several practical advantages: (1) It is much easier to implement; (2) it can be easily

Dan Kiselman

The astrophysically very interesting Li I 671 nm line has been observed with high spatial resolution in solar granulation with the intention to diagnose departures from local thermodynamic equilibrium (LTE) in the line formation. The spectral feature is very weak, so this is also a test on the limits of such observations. The observations of the Li I line an

Giovanni Carraro, Cesario Lia, Fulvio Buonomo

We present preliminary results on galactic Dark Matter (DM), halo structure, and galaxy evolution. We show how during the first Gyr of the evolution of a $10^{10} M_{\odot}$ dwarf elliptica feed-back from stars (SNæ~ and stellar winds) leads to an extended constant density isothermal core with radius of 0.15 the virial radius $R_{200}$. We also present first

Ilya V. Karlin, V. B. Zmievskii

We develop the principle of dynamic invariance to obtain closed moment equations from the Fokker-Planck kinetic equation. The analysis is carried out to explicit formulae for computation of the lowest eigenvalue and of the corresponding eigenfunction for arbitrary potentials.

Stefanie Wachter, Alan P. Smale

We have studied the optical counterparts of X1755-338 and X1658-298 in their X-ray "off" states. The first observations of X1755-338 in quiescence show that the counterpart, V4134 Sgr, has faded by more than 3.5 mag in V. If the mass donor in the system is an M0V star as implied by the period, our upper limits on the brightness of the counterpart sug

M. Carena, R. L. Culbertson, S. Eno, H. J. Frisch

A review of the status of searches for Supersymmetry at the Tevatron Collider as of the Summer of 1997. This is a new version of the previous review, substantially shortened to fit editorial guidelines, and significantly different to warrant a separate posting. To appear in "Perspectives on Supersymmetry", ed. G.L. Kane (World Scientific, Singapore).

Felix Finster, Joel Smoller, Shing-Tung Yau

We consider the coupled Einstein-Dirac-Maxwell equations for a static, spherically symmetric system of two fermions in a singlet spinor state. Soliton-like solutions are constructed numerically. The stability and the properties of the ground state solutions are discussed for different values of the electromagnetic coupling constant. We find solutions even wh

B. M. Chibisov, M. B. Voloshin

We show that the longitudinal polarization of the top quarks produced in the annihilation of e+ e- or mu+ mu- into tbar t at energies near the threshold is not affected by the large Coulomb-type corrections, which greatly modify the total cross section. Thus the longitudinal polarization, although small, may provide an independent information on the mass and

Rajesh Gopakumar, Cumrun Vafa

We consider topological closed string theories on Calabi-Yau manifolds which compute superpotential terms in the corresponding compactified type II effective action. In particular, near certain singularities we compare the partition function of this topological theory (the Kodaira-Spencer theory) to $SU(\infty)$ Chern-Simons theory on the vanishing 3-cycle.

Daniele Guido, Tommaso Isola

Given a C*-algebra A with a semicontinuous semifinite trace tau acting on the Hilbert space H, we define the family R of bounded Riemann measurable elements w.r.t. tau as a suitable closure, a la Dedekind, of A, in analogy with one of the classical characterizations of Riemann measurable functions, and show that R is a C*-algebra, and tau extends to a semico

Spyros Skoulakis, Steven Thomas

We consider the application of logarithmic conformal field theory in finding solutions to the turbulent phases of 2-dimensional models of magnetohydrodynamics. These arise upon dimensional reduction of standard (infinite conductivity) 3-dimensional magnetohydrodynamics, after taking various simplifying limits. We show that solutions of the corresponding Hopf

Domenico Giulini

The general validity of the area law for black holes is still an open problem. We first show in detail how to complete the usually incompletely stated text-book proofs under the assumption of piecewise $C^2$-smoothness for the surface of the black hole. Then we prove that a black hole surface necessarily contains points where it is not $C^1$ (called ``cusps&

J. Bernabeu, D. Gomez Dumm, G. Orlandini

The nuclear electric polarizability is theoretically analyzed using a sum rule derived from the longitudinal part of the forward Compton amplitude. Beyond the leading dipole contribution, this approach leads to the presence of potential-dependent terms that do not show up in previous analyses. The significance of these new contributions is illustrated by per

G. Date, M. V. N. Murthy, Radhika Vathsan

We report on a study of a classical, finite system of confined particles in two dimensions with a two-body repulsive interaction. We first develop a simple analytical method to obtain equilibrium configurations and energies for few particles. When the confinement is harmonic, we prove that the first transition from a single shell occurs when the number of pa

L. Moriconi, F. I. Takakura

We study the large $λ$ limit of the loop-dependent characteristic functional $Z(λ)=<\exp(iλ\oint_c \vec v \cdot d \vec x)>$, related to the probability density function (PDF) of the circulation around a closed contour $c$. The analysis is carried out in the framework of the Martin-Siggia-Rose field theory formulation of the turbulence problem, by means of th

S. Krasnikov

We analyze the &#34;F-locality condition&#34; (proposed by Kay to be a mathematical implementation of a philosophical bias related to the equivalence principle, we call it the &#34;GH-equivalence principle&#34;), which is often used to build a generalization of quantum field theory to non-globally hyperbolic spacetimes. In particular we argue that the theore

C. E. Campbell, E. Krotscheck, M. Saarela

We develop a microscopic theory of the scattering, transmission, and sticking of 4He atoms impinging on a superfluid 4He slab at near normal incidence, and inelastic neutron scattering from the slab. The theory includes coupling between different modes and allows for inelastic processes. We find a number of essential aspects that must be observed in a physic

D. C. Cabra, A. Honecker, P. Pujol

In this paper we continue and extend a systematic study of plateaux in magnetization curves of antiferromagnetic Heisenberg spin-1/2 ladders. We first review a bosonic field-theoretical formulation of a single XXZ-chain in the presence of a magnetic field, which is then used for an Abelian bosonization analysis of N weakly coupled chains. Predictions for the

D. A. Head, G. J. Rodgers

The Bak-Sneppen model is shown to fall into a different universality class with the introduction of a preferred direction, mirroring the situation in spin systems. This is first demonstrated by numerical simulations and subsequently confirmed by analysis of the multi-trait version of the model, which admits exact solutions in the extremes of zero and maximal

Yuan-Ben Dai, Shi-Lin Zhu

The couplings of pions with lowest three doublets (0^-,1^-), (0^+,1^+) and (1^+,2^+) of heavy mesons are studied with ligh cone QCD sum rules in the leading order of heavy quark effective theory. The ambiguity due to the presence of two distinct 1^+ states are solved.

Shi-Lin Zhu, Yuan-Ben Dai

The couplings of pions with heavy baryons g_2 (Σ^*, Σ) and g_3(Σ^*, Λ) are studied with light-cone QCD sum rules in the leading order of heavy quark effective theory. Both sum rules are stable. Our results are g_2=(1.56\pm 0.3), g_3=(0.94\pm 0.06).

Shi-Lin Zhu, Yuan-Ben Dai

The couplings and decay widths of the proceses (1^+,2^+)->(0^-,1^-)+rho are studied with ligh-cone QCD sum rules in the leading order of heavy quark effective theory. These processes are employed to estimate the two pion transition widths of the (1^+,2^+) doublet through the low mass tail of the rho resonance. Our calculation shows that the two pion decay wi

Yuan-Ben Dai, Shi-Lin Zhu

We first improve the previous results on the masses of the doublets (0^+,1^+) and (1^+,2^+) with QCD sum rules up to the order of O(1/m_Q) in the framework of HQET and calculate the O(1/m_Q) correction to the decay constants f_{-,1/2} and f_{+,3/2}. With the mass matrix of the two 1^+ states, we obtain the mixing angle for the two states and the interpolatin

Otto C. W. Kong, Brian D. Wright

We demonstrate that a certain class of low scale supersymmetric ``Nelson-Barr&#39;&#39; type models can solve the strong and supersymmetric CP problems while at the same time generating sufficient weak CP violation in the $K^{0}-\bar{K}^{0}$ system. In order to prevent one-loop corrections to $\barθ$ which violate bounds coming from the neutron electric dipo

Yu Song-Ju, Kouichi Toda, Takeshi Fukuyama

Integrable equations in ($1 + 1$) dimensions have their own higher order integrable equations, like the KdV, mKdV and NLS hierarchies etc. In this paper we consider whether integrable equations in ($2 + 1$) dimensions have also the analogous hierarchies to those in ($1 + 1$) dimensions. Explicitly is discussed the Bogoyavlenskii-Schiff(BS) equation. For the

Gennady P. Berman, Gary D. Doolen, Gustavo V. López, V. I. Tsifrinovich

The physical implementation of the quantum Control-Not gate for a two-spin system is investigated numerically. The concept of a generalized quantum Control-Not gate, with arbitrary phase shift, is introduced. It is shown that a resonant $π$-pulse provides a simple example of a generalized quantum Control-Not gate.

G. Lévai, B. Kónya, Z. Papp

Quantum mechanical models and practical calculations often rely on some exactly solvable models like the Coulomb and the harmonic oscillator potentials. The $D$ dimensional generalized Coulomb potential contains these potentials as limiting cases, thus it establishes a continuous link between the Coulomb and harmonic oscillator potentials in various dimensio

P. Busch

The quantum measurement problem is formulated in the form of an insolubility theorem that states the impossibility of obtaining, for all available object preparations, a mixture of states of the compound object and apparatus system that would represent definite pointer positions. A proof is given that comprises arbitrary object observables, whether sharp or

Michael L. G. Redhead, Fabian Wagner

A conjecture concerning vacuum correlations in axiomatic quantum field theory is proved. It is shown that this result can be applied both in the context of EPR-type experiments and Bell-type experiments.

H. F. Chau

I report two general methods to construct quantum convolutional codes for quantum registers with internal $N$ states. Using one of these methods, I construct a quantum convolutional code of rate 1/4 which is able to correct one general quantum error for every eight consecutive quantum registers.

Takaomi Shigehara, Hiroshi Mizoguchi, Taketoshi Mishima, Taksu Cheon

In this paper, we show that two-dimensional billiards with point interactions inside exhibit a chaotic nature in the microscopic world, although their classical counterpart is non-chaotic. After deriving the transition matrix of the system by using the self-adjoint extension theory of functional analysis, we deduce the general condition for the appearance of

Bogdan Mihaila, Jochen H. Heisenberg

We discuss the computation of two-body matrix elements from the Argonne $v_{18}$ interaction. The matrix elements calculation is presented both in particle-particle and in particle-hole angular momentum coupling. The procedures developed here can be applied to the case of other NN potentials, provided that they have a similar operator format.

Gregor Penner, Thomas Feuster, Ulrich Mosel

By introducing electromagnetic formfactors in the spacelike region we extend an effective, gauge invariant Lagrangian model considering Born terms, baryon resonances up to 1.7 GeV and vector meson contributions (Rho, Omega) to calculate electroproduction of Pi-mesons. This model forms the basis for predictions of pion induced dilepton production on the nucle

R. Shyam, H. Lenske

We calculate the cross sections of the elastic and inelastic breakup modes for the inclusive breakup reaction $^{28}$Si($^8$B,$^7$Be) at beam energies between 10 - 40 MeV/nucleon within a direct fragmentation model formulated in the framework of the post form distorted-wave Born-approximation. In contrast to the case of the stable isotopes, the inelastic bre

Subir Bhattacharyya, Abhee K. Dutt- Mazumder, Binayak Dutta-Roy, Bikash Sinha

We investigate the equation of state (EOS) for nuclear matter, within the framework of the Relativistic Hartree Fock (RHF) theory, with special emphasis on the role of the Pauli coupling of the vector meson $ρ$ to the nucleon vis-a-vis the eventual softening of the EOS as revealed through a substantial reduction of the incompressibility parameter ($K_0$) for

M. Asakawa, H. Minakata, B. Muller

We give two reasons why we believe that non-central ultrarelativistic heavy ion collisions are the place to look for the disoriented chiral condensates (DCC). First, we argue that the most probable quench scenario for the formation of DCC requires non-central collisions. Second, we show by numerical simulations that strong electromagnetic fields of heavy ion

Jason Fulman

For W a finite Coxeter group, a formula is found for the size of W equivalence classes of subsets of a base. The proof is a case-by-case analysis using results and tables of Carter and Orlik/Solomon. As a corollary we obtain an alternating sum identity which generalizes a well-known identity from the theory of Coxeter groups.

Jean-Luc Brylinski, Gregg Zuckerman

We introduce a canonical outer vector field on a Poisson manifold, also due independently to A. Weinstein. We view it as a global section of the sheaf of Poisson vector fields modulo the subsheaf of hamiltonian vector fields. We study this outer derivation mostly in the case of holomorphic Poisson manifolds.

Sijong Kwak

Castelnuovo-Mumford regularity is an important invariant of projective algebraic varieties. A well known conjecture due to Eisenbud and Goto gives a bound for regularity in terms of the codimension and degree. This conjecture is known to be true for curves (Gruson-Lazarsfeld-Peskine) and smooth surfaces (Pinkham, Lazarsfeld), but not in general. The purpose

N. Kitazawa, F. Sannino

We explore a novel way of deriving the effective Higgs Lagrangian from strongly interacting vector-like gauge theories. We consider the N=1 supersymmetric extension of gauge theories and interpret the auxiliary field associated with the low energy effective &#34;meson&#34; superfield as the Higgs field. By introducing an explicit supersymmetry breaking term

Edward Farhi, Noah Graham, Peter E. Haagensen, Robert L. Jaffe

We develop an unambiguous and practical method to calculate one-loop quantum corrections to the energies of classical time-independent field configurations in renormalizable field theories. We show that the standard perturbative renormalization procedure suffices here as well. We apply our method to a simplified model where a charged scalar couples to a neut

D. C. Cabra, P. Pujol, C. von Reichenbach

We study the long wavelength limit of a spin S Heisenberg antiferromagnetic chain. The fermionic Lagrangian obtained corresponds to a perturbed level 2S SU(2) Wess-Zumino-Witten model. This effective theory is then mapped into a compact U(1) boson interacting with Z_{2S} parafermions. The analysis of this effective theory allows us to show that when S is an

Marco Cavaglia

We present a solvable model of two-dimensional dilaton-gravity coupled to a massless scalar field. We locally integrate the field equations and briefly discuss the properties of the solutions. For a particular choice of the coupling between the dilaton and the scalar field the model can be interpreted as the two-dimensional effective theory of 2+1 cylindrica

Kimyeong Lee

We investigate Yang-Mills theories with arbitrary gauge group on $R^3\times S^1$, whose symmetry is spontaneously broken by the Wilson loop. We show that instantons are made of fundamental magnetic monopoles, each of which has a corresponding root in the extended Dynkin diagram. The number of constituent magnetic monopoles for a single instanton is the dual

Y. S. Kim

If Einstein&#39;s photon is $E = cp = \hbarω$, Wigner&#39;s photon is its helicity which is a Lorentz-invariant concept coming from the E(2)-like little group for massless particles. In addition, the E(2)-like little group has two translation-like degrees of freedom. What happens to them? They are associated with the gauge degree of freedom. Since the physic

Valeri Frolov, Dmitri Fursaev

In this review we describe statistical mechanics of quantum systems in the presence of a Killing horizon and compare statistical-mechanical and one-loop contributions to black hole entropy. Studying these questions was motivated by attempts to explain the entropy of black holes as a statistical-mechanical entropy of quantum fields propagating near the black

Gordon Chalmers, Warren Siegel

We introduce a self-dual field strength which replaces the gauge field in spontaneously broken Yang-Mills theory, reformulating it as a Lorentz covariant non-linear sigma model. This dualized theory is in both a unitary and renormalizable gauge: The self-dual field strength has exactly the three components necessary to describe a massive vector field. In fut

Aharon Davidson, Tomer Schwartz, Raymond R. Volkas

A link is established between the observed (approximate) geometric mass hierarchy of quarks and leptons and the triangular structure of their tenable flavor representations. This singles out SU(3) as the horizontal flavor group, thereby linking the Fermi mass hierarchy with the threefold family replication. These linkages are exploited within a flavor-chiral

Ruth Haeckl, Viktor Hund, Hartmut Pilkuhn

An eight-component formalism is proposed for the relativistic two-fermion problem. In QED, it extends the applicability of the Dirac equation with hyperfine interaction to the positronium case. The use of exact relativistic two-body kinematics entails a CP-invariant spectrum which is symmetric in the total cms energy. It allows the extension of recent α^6 re

Gustavo Burdman

We discuss the constraints from rare B and K decays on the Electroweak Symmetry Breaking (EWSB) sector, as well as on theories of fermion masses. We focus on models involving new strong dynamics and show that transitions involving Flavor Changing Neutral Currents (FCNC) play an important role in disentangling the physics in these scenarios. In a model-indepe

J. Binnewies, B. A. Kniehl, G. Kramer

We provide nonperturbative fragmentation functions for B mesons, both at leading and next-to-leading order in the MS-bar factorization scheme with five massless quark flavors. They are determined by fitting the fractional energy distribution of B mesons inclusively produced in e^+ e^- annihilation at CERN LEP1. Theoretical predictions for the inclusive produ

S. Munier, R. Peschanski

High energy factorization predictions for F2^c are derived using BFKL descriptions of the proton structure function F2 at HERA. The model parameters are fixed by a fit of F2 at small x. Two different approaches of the non perturbative proton input are shown to correspond to the factorization at the gluon or quark level, respectively. The predictions for F2^c

Marcelo Gleiser

The dynamics of phase transitions plays a crucial rôle in the so-called interface between high energy particle physics and cosmology. Many of the interesting results generated during the last fifteen years or so rely on simplified assumptions concerning the complex mechanisms typical of nonequilibrium field theories. After reviewing well-known results concer

Debrupa Chakraverty, Triptesh De, Binayak Dutta-Roy, K. S. Gupta

We derive a theoretically allowed domain for the charge radius $ρ$ and curvature $c$ of the Isgur-Wise function describing the decay $Λ_b \to Λ_c l {\bar ν_l}$. Our method uses crossing symmetry, dispersion relations and analyticity in the context of the Heavy Quark Effective Theory but is independent of the specifics of any given model. The experimentally d

Chun Liu

Orbitally excited L=1 charm mesons are studied by QCD sum rules in the framework of heavy quark effective theory. The meson masses and the strong decay widths are obtained. This talk is based on our works of refs. 1 and 2 collaborated with Y.B. Dai, C.S. Huang, M.Q. Huang and H.Y. Jin.

Jihn E. Kim

In view of the ongoing galactic (or cosmic) axion detection experiments, we compare the axion-photon-photon coupling $c_{aγγ}$&#39;s for various invisible (or very light) axion models.

J. J. Godina, Y. Meurice, M. B. Oktay

Using recently developed methods, we perform high-accuracy calculations of the susceptibility near beta_c for the D=3 version of Dyson's hierarchical model. Using linear fits, we estimate the leading gamma and subleading Delta exponents. Independent estimates are obtained by calculating the first two eigenvalues of the linearized renormalization group transf

Jorge L. Rodriguez

A review of current experimental results on exclusive hadronic decays of bottom mesons to a single or double charmed final state is presented. We concentrate on branching fraction measurements conducted at $e^+e^-$ colliders at the $Υ(4s)$ and at the $Z^0$ resonance. The experimental results reported are then used in tests of theoretical model predictions, t

M. E. Rupright, A. M. Abrahams, L. Rezzolla

We present a new method of extracting gravitational radiation from three-dimensional numerical relativity codes and providing outer boundary conditions. Our approach matches the solution of a Cauchy evolution of Einstein&#39;s equations to a set of one-dimensional linear wave equations on a curved background. We illustrate the mathematical properties of our

Robert Paternoga, Robert Graham

The Bianchi IX mixmaster model is quantized in its non-diagonal form, imposing spatial diffeomorphism, time reparametrization and Lorentz invariance as constraints on physical state vectors before gauge-fixing. The result turns out to be different from quantizing the diagonal model obtained by gauge-fixing already on the classical level. For the non-diagonal

B. Boisseau, B. Linet

We determine in closed form the general static solution with cylindrical symmetry to the Brans-Dicke equations for an energy-momentum tensor corresponding to the one of the straight U(1) global string outside the core radius assuming that the Goldstone boson field takes its asymptotic value

John Baker, Raymond Stanley Puzio

This work consists of two distinct parts. In the first part we present a new method for solving the initial value problem of general relativity. Given any spatial metric with a surface orthogonal Killing field and two freely specified components of the extrinsic curvature we solve for extrinsic curvature&#39;s remaining components. For the second part, after

G. F. R. Ellis, D. M. Solomons

We consider compensated spherical lens models and the caustic surfaces they create in the past light cone. Examination of cusp and crossover angles associated with particular source and lens redshifts gives explicit lensing models that confirm previous claims that area distances can differ by substantial factors from angular diameter distances even when aver

Jean-Luc Brylinski

We introduce the beta function of a knot in euclidean three-space. This is a meromorphic function of a complex variable which we prove admits a Bernstein type functional equation. We determine the first residues.

J. M. Tranquada

Neutron and X-ray scattering studies have provided strong evidence for coupled spatial modulations of charge and spin densities in layered nickelates and cuprates. The accumulated results for La(2-x)Sr(x)NiO(4+d) are consistent with the strongly-modulated topological-stripe concept. Clues from Nd-doped La(2-x)Sr(x)CuO(4) suggest similar behavior for the cupr

Mucio A. Continentino

A previous scaling analysis of pressure experiments in heavy fermion is reviewed and enlarged. We show that the critical exponents obtained from this analysis indicate that a one-parameter scaling describes these experiments. We obtain explicitly the enhancemente factors showing that these systems are indeed near criticality and that the scaling approach is

J. Dziarmaga, W. Zakrzewski

We study the diffusion and deformation of classical solitons coupled to thermal noise. The diffusion coefficient for kinks in the $ϕ^4$ theory is predicted up to the second order in $kT$. The prediction is verified by numerical simulations. Multiskyrmions in the vector O(3) sigma model are studied within the same formalism. Thermal noise results in a diffusi

Taeseung Choi, Chang-Mo Ryu, A. M. Jayannavar

We have calculated the persistent spin current of an open ring induced by the Aharonov-Casher phase. For unpolarized electrons there exist no persistent charge currents, but persistent spin currents. We show that, in general, the magnitude of the persistent spin current in a ring depends on the direction of the direct current flow from one reservoir to anoth

Mario Castro, Rodolfo Cuerno, Angel S\anchez, Francisco Domínguez-Adame

We study the interface dynamics of a discrete model to quantitatively describe electrochemical deposition experiments. Extensive numerical simulations indicate that the interface dynamics is unstable at early times, but asymptotically displays the scaling of the Kardar-Parisi-Zhang universality class. During the time interval in which the surface is unstable

M. Benakli, E. Granato, S. R. Shenoy, M. Gabay

The effects of random dilution of junctions on a two-dimensional Josephson-junction array in a magnetic field are considered. For rational values of the average flux quantum per plaquette $f$, the superconducting transition temperature vanishes, for increasing dilution, at a critical value $x_S(f)$, while the vortex ordering remains stable up to $x_{VL}>x_S$