September 1993 arXiv papers — page 3

Louis Crane, Louis H. Kauffman, David N. Yetter

Recent work of Roberts has shown that the first surgical 4-manifold invariant of Broda and (up to an unspecified normalization factor) the state-sum invariant arising from the TQFT of Crane-Yetter are equivalent to the signature of the 4-manifold. Subsequently Broda defined another surgical invariant in which the 1- and 2-handles are treated differently. We

H. Fujii, Y. Mimura, K. Sasaki, T. Sasaki

We examine the muonium ($μ^+e^-$)-antimuonium ($μ^-e^+$) system in the models which accomodate the dilepton gauge bosons, and study their contributions to the ground state hyperfine splitting in ``muonium''. We also consider the exotic muon decay $μ^+\to e^+ +\overline ν_e +ν_μ$ mediated by the dilepton gauge boson, and obtain a lower bound $(M_{X^{\

Anil K. Trivedi

Introducing a new and universally applicable discretizing technique, I construct a class of local and unitary lattice theories of Weyl neutrinos; this solves a longstanding and allegedly unsolvable problem in quantum field theory. En route, I also prove a general ``go'' theorem that all Lagrangian-density based continuum quantum field theories can be

Anil K. Trivedi

The Nielsen-Ninomiya no-go theorem asserts that chiral Weyl~(``neutrino'') fields cannot exist on lattices. However, the actual mathematical arguments advanced in the theorem fail to make that case. The theorem leaves the problem of lattice neutrinos completely open; it identifies no obstacle which would prevent us from discretizing chiral theories.

Pijush K. Ghosh

We consider a generalization of the abelian Higgs model with a Chern-Simons term by modifying two terms of the usual Lagrangian. We multiply a dielectric function with the Maxwell kinetic energy term and incorporate nonminimal interaction by considering generalized covariant derivative. We show that for a particular choice of the dielectric function this mod

E. Kiritsis

Duality symmetries for strings moving in non-trivial spacetime backgrounds are analysed. It is shown that, for backgrounds generated from compact WZW and coset models, such duality symmetries are exact to all orders in string perturbation theory. A global treatment of duality symmetries is given, by associating them to the known symmetries of affine current

D. Boulatov

The matrix model with a Bethe-tree embedding space (coinciding at large $N$ with the Kazakov-Migdal ``induced QCD'' model \cite{KM}) is investigated. We further elaborate the Riemann-Hilbert approach of \rf{Mig1} assuming certain holomorphic properties of the solution. The critical scaling (an edge singularity of the density) is found to be $γ_{str}

Zbigniew Hasiewicz, Przemysł{aw} Siemion, Walter Troost

The phase space of a particle on a group manifold can be split in left and right sectors, in close analogy with the chiral sectors in Wess Zumino Witten models. We perform a classical analysis of the sectors, and the geometric quantization in the case of $SU(2)$. The quadratic relation, classically identifying $SU(2)$ as the sphere $S^3$, is replaced quantum

Tadashi Kon, Toshihiko Nonaka

\def\nle{{\stackrel{<}{\sim}}} We examine a possibility for existence of a light supersymmetric partner of the top quark (stop) with mass 15 $\sim$ 20 GeV in the framework of the minimal supergravity GUT model. Such light stop could explain the slight excess of the high $p_{T}$ cross section of the $D^{*\pm}$-meson production in two-photon process at TRISTAN

Karl B. Fisher, Caleb A. Scharf, Ofer Lahav

We present a formalism for analysing redshift distortions based on a spherical harmonic expansion of the density field. We use a maximum likelihood estimator for the combination of density and bias parameters, $Ω^0.6/b$. We test the method with $N$-body simulations and apply it to the 1.2 Jy IRAS redshift survey.

L. Frankfurt, l, G. A. Miller, M. Strikman

A QCD-based treatment of projectile size fluctuations is used to compute inelastic diffractive cross sections $σ_{diff}$ for coherent hadron-nuclear processes. We find that fluctuations near the average size give the major contribution to the cross section with $ \le few \%$ contribution from small size configurations. The computed values of $σ_{diff}$ are c

P. S. Aspinwall, B. R. Greene, D. R. Morrison

We analyze the moduli spaces of Calabi-Yau threefolds and their associated conformally invariant nonlinear sigma-models and show that they are described by an unexpectedly rich geometrical structure. Specifically, the Kahler sector of the moduli space of such Calabi-Yau conformal theories admits a decomposition into adjacent domains some of which correspond

M. Matone

Based on a recent paper by Takhtajan, we propose a formulation of 2D quantum gravity whose basic object is the Liouville action on the Riemann sphere $Σ_{0,m+n}$ with both parabolic and elliptic points. The identification of the classical limit of the conformal Ward identity with the Fuchsian projective connection on $Σ_{0,m+n}$ implies a relation between co

W. de Boer, T. Kussmaul, IEKP Karlsruhe

A determination of the hadronic fragmentation functions of the Z-boson is presented from a study of the inclusive hadron production wit the DELPHI detector at LEP. These fragmentation functions were compared with the ones at lower energies, thus covering data in a large kinematic range: 196 <= Q^2 <= 8312 GeV^2 and x(= p_h/E_beam) > 0.08 A large scaling viol

Minos Axenides, Andrei Johansen, Holger Bech Nielsen

We present a simple exactly solvable quantum mechanical example of the global anomaly in an $O(3)$ model with an odd number of fermionic triplets coupled to a gauge field on a circle. Because the fundamental group is non-trivial, $\pi_1 (O(3)) ={\bf Z}_2$, fermionic level crossing or circling occur in the eigenvalue spectrum of the 1-dim. Dirac \op under con

Sergei V. Zenkin

We study the phase structure of a $Z_2$ lattice Higgs-Yukawa system with different forms of chirally invariant lattice fermion actions: naive, two types of non-local actions, and a mirror fermion action. The calculations are performed in the variational mean field approximation with contribution of fermionic determinant being calculated in a ladder approxima

Bao, Engvik, Hjorth-Jensen, Osnes

We calculate the total mass, radius, moment of inertia and surface gravitational redshift for neutron stars using various equations of state. The latter are derived from recent meson-exchange potential models, employing both a relativistic and a non-relativistic Brueckner-Hartree-Fock approach.

D. R. Phillips, I. R. Afnan

This paper is the first in a series of three which attempt to resolve the difficulties that have plagued the $NN-πNN$ problem for the past ten years. Various theoretical inconsistencies in the current formulation have been pointed out and this work aims to eliminate these inconsistencies and so, we hope, produce agreement with experiment. This is to be done

A. P. de Almeida, F. T. Brandt, J. Frenkel

We study the one-loop contributions of matter and radiation to the gravitational polarization tensor at finite temperatures. Using the analytically continued imaginary-time formalism, the contribution of matter is explicitly given to next-to-leading ($T^2$) order. We obtain an exact form for the contribution of radiation fields, expressed in terms of general

Peter West

Recent progress on the physical states and scattering amplitudes of the $W_3$ string is reviewed with particular emphasis on the relation between this string theory and the Ising model.

Ken-ji Hamada

The nonlinear structures in 2D quantum gravity coupled to the $(q+1,q)$ minimal model are studied in the Liouville theory to clarify the factorization and the physical states. It is confirmed that the dressed primary states outside the minimal table are identified with the gravitational descendants. Using the discrete states of ghost number zero and one we c

David C. Dunbar, Keith G. Joshi

We present coset conformal field theories whose spectrum is not determined by the identification current method. In these ``maverick&#39;&#39; cosets there is a larger symmetry identifying primary fields than under the identification current. We find an A-D-E classification of these mavericks. }

A. Szczepaniak, C-R. Ji, S. R. Cotanch

We study the most general, relativistic, constituent $q{\overline q}$ meson wave function within a new covariant framework. We find that by including a tensor wave function component, a pure valence quark model is now capable of reproducing not only all static pion data ($f_π$, $\langle r_π^2 \rangle$) but also the distribution amplitude, form factor $(F_π(Q

Joao P. Silva, L. Wolfenstein

A major goal in B physics is measuring the CP-violating asymmetry in the decay $B^0 \rightarrow \pi^+ \pi^-$. In order to determine one of the phase angles in the CKM matrix from this decay it is necessary to determine the influence of the penguin amplitude. Here we show how, using $SU(3)$ symmetry, the penguin effect can be approximately determined from the

A. Szczepaniak, C-R. Ji, S. R. Cotanch

We study the implications of Lorentz symmetry for hadronic structure by formulating a manifestly covariant constituent quark model and find full covariance for any Lorentz transformation requires utilizing a variable quantization surface. Even though time-reversal invariance mandates a unique orientation for the surface&#39;s direction, we investigated alter

M. Bastero-Gil, V. Manías, J. Pérez-Mercader

We discuss the effect of the renormalization procedure in the computation of the unification point for running coupling constants. We explore the effects of threshold--crossing on the $β$--functions. We compute the running of the coupling constants of the Standard Model, between $m_Z$ and $M_P$, using a mass dependent subtraction procedure, and then compare

A. Szczepaniak, C-R. Ji, S. R. Cotanch

Using heavy quark symmetry we construct an energy sum rule relating the form factor of a heavy flavored meson $ξ(w)$ to the light quark energy distribution. We find that the current available data for $ξ(w)$ is consistent with a broad energy distribution rather than with that of a pure quark/anti-quark bound state, indicating a large nonvalence content.

K. M. Bitar

We present results of a lattice simulation of quantum chromodynamics with two degenerate flavors of dynamic Wilson fermions at $6/g^2=5.3$ at each of two dynamical fermion hopping parameters, $κ=0.1670$ and 0.1675, corresponding to pion masses in lattice units of about 0.45 and 0.31. The simulations include three other values of valence quark mass, in additi

J. E. S. Socolar, M. E. Bleich

We introduce a simple one-dimensional sandpile model that undergoes relaxation oscillations. A single model can account for self-organized critical behavior and relaxation oscillations, depending on the manner in which it is driven, mirroring the experimental situation for real sandpiles. The relaxation oscillations are robust with respect to minor modificat

Terence Hwa, Daniel S. Fisher

Some of the properties of the low temperature vortex-glass phase of randomly-pinned flux lines in 1+1 dimensions are studied. The flux arrays are found to be sensitive to small changes in external parameters such as the magnetic field or temperature. These effects are captured by the variations in the magnetic response and noise, which have universal statist

Partha P. Mitra, Bertrand I. Halperin

Infrared transmission measurements on the $S=1$ antiferromagnetic chain compound NENP in applied magnetic fields show a sharp absorption line at the field-shifted Haldane gap. This violates a wave-vector selection rule of the Hamiltonian normally used for NENP, as the gap excitations occur at the Brillouin zone boundary. We argue that the crystal structure a

Michael A. Nowak

In this letter we explore the suggestion of Quashnock and Lamb (1993) that nearest neighbor correlations among gamma ray burst positions indicate the possibility of burst repetitions within various burst sub-classes. With the aid of Monte Carlo calculations we compare the observed nearest neighbor distributions with those expected from an isotropic source po

R. Manka, I. Bednarek

The model of the supersymmetrical ball in the supersymmetrical standard model with additional global U(1) fermion symmetry is presented. We show that the supersymmetry breaking scale ( R-parity ), the global U(1) fermion symmetry scale and the electroweak symmetry breaking scale are strictly connected to each other. The realistic ball with $M \sim 10^5 - 10^

Margarita Garcia Perez, Antonio Gonzalez-Arroyo, Jeroen Snippe, Pierre van Baal

Lattice artefacts are used, through modified lattice actions, as a tool to find the largest instantons in a toroidal geometry [0,L]^3X[0,T] for T to infinity. It is conjectured that the largest instanton is associated with tunnelling through a sphaleron. Existence of instantons with at least 8 parameters can be proven with the help of twisted boundary condit

Sanghyeon Chang, Jihn E. Kim

We suggest the fermion doubling for all quarks and leptons. It is a generalization of the neutrino doubling of the seesaw mechanism. The new quarks and leptons are $SU(2)$ singlets and carry the electromagnetic charges of their lighter counterparts. An $SU(3)$ {\it anomaly free global symmetry} or a discrete symmetry can be introduced to restrict the Yukawa

M. Hjorth-Jensen, H. Müther, A. Polls

In this work we evaluate the imaginary part of the isobar $Δ$ self-energy $Σ_Δ$ from the two-body absorption process $Δ+N\rightarrow 2N$. This contribution is calculated using a recently developed non-relativistic scheme, which allows for an evaluation of the self-energy with a basis of single-particle states appropriate for both bound hole states and for pa

Jiří Witzany

If $S,T$ are stationary subsets of a regular uncountable cardinal $κ$, we say that $S$ reflects fully in $T$, $S<T$, if for almost all $α\in T$ (except a nonstationary set) $S \cap α$ is stationary in $α.$ This relation is known to be a well founded partial ordering. We say that a given poset $P$ is realized by the reflection ordering if there is a maximal a

Andreas Blass

A category used by de Paiva to model linear logic also occurs in Vojtas&#39;s analysis of cardinal characteristics of the continuum. Its morphisms have been used in describing reductions between search problems in complexity theory. We describe this category and how it arises in these various contexts. We also show how these contexts suggest certain new mult

P V Landshoff

Canonical quantisation gives a new and convenient finite-temperature perturbation theory in covariant gauges, and solves the problem of the zero-frequency mode in the temporal gauge. [Talk at Workshop on Thermal Field Theories and their Applications, Banff, August 1993]

J. O. Madsen, M. Sakamoto

Closed bosonic string theory on toroidal orbifolds is studied in a Lagrangian path integral formulation. It is shown that a level one twisted WZW action whose field value is restricted to Cartan subgroups of simply-laced Lie groups on a Riemann surface is a natural and nontrivial extension of a first quantized action of string theory on orbifolds with an ant

H. Arodz, A. L. Larsen

Dynamics of cylindrical and spherical relativistic domain walls is investigated with the help of a new method based on Taylor expansion of the scalar field in a vicinity of the core of the wall. Internal oscillatory modes for the domain walls are found. These modes are non-analytic in the &#34;width&#34; of the domain wall. Rather non-trivial transformation

Dennis Bonatsos, C. Daskaloyannis, K. Kokkotas

Quantum superintegrable systems in two dimensions are obtained from their classical counterparts, the quantum integrals of motion being obtained from the corresponding classical integrals by a symmetrization procedure. For each quantum superintegrable systema deformed oscillator algebra, characterized by a structure function specific for each system, is cons

M. B. Halpern

In this talk, I will review the foundations of irrational conformal field theory (ICFT), which includes rational conformal field theory as a small subspace. Highlights of the review include the Virasoro master equation, the Ward identities for the correlators of ICFT and solutions of the Ward identities. In particular, I will discuss the solutions for the co

R. Arnowitt, Pran Nath

A survey is given of supersymmetry and supergravity and their phenomenology. Some of the topics discussed are the basic ideas of global supersymmetry, the minimal supersymmetric Standard Model (MSSM) and its phenomenology, the basic ideas of local supersymmetry (supergravity), grand unification, supersymmetry breaking in supergravity grand unified models, ra

A. Szczepaniak, A. G. Williams

We study the pion electromagnetic and $\gamma^* + \pi^0 \to \gamma$ transition form factors at intermediate momentum transfer. We calculate soft, nonperturbative corrections to the leading perturbative amplitudes which arise from the $q\bar q$-component of the pion wave function. We work in Minkowski space and use a Lorentz covariant, gauge-invariant general

M. Carena, B. Lampe, C. E. M. Wagner

A Majorana mass term for the $τ$ neutrino would induce neutrino - antineutrino mixing and thereby a process which violates fermion number by two units. We study the possibility of distinguishing between a massive Majorana and a Dirac $τ$ neutrino, by measuring fermion number violating processes in a deep inelastic scattering experiment $νp \rightarrow τX$. W

Sanghyeon Chang, Jihn E. Kim

We show that heavy quark axion is not necessarily a hadronic axion, which manifests in the quark and lepton seesaw mechanism. We introduce a heavy $SU(2)$ singlet fermion for each known fermion in order to unify the axion scale and the seesaw scale. The light quarks and leptons gain their masses by the seesaw mechanism. Even though our axion model gives a ki

Victor M. Villalba

In the present article we solve, via separation of variables, the massless Dirac equation in a nonstationary rotating, causal Gödel-type cosmological universe, having a constant rotational speed in all the points of the space. We compute the frequency spectrum. We show that the spectrum of massless Dirac particles is discrete and unbounded.

E. Granato, M. A. Continentino

The effects of the charging energy in the superconducting transition of granular materials or Josephson junction arrays is investigated using a pseudospin one model. Within a mean-field renormalization-group approach, we obtain the phase diagram as a function of temperature and charging energy. In contrast to early treatments, we find no sign of a reentrant

Christopher Mudry, Eduardo Fradkin

In this paper we reexamine the problem of the separation of spin and charge degrees of freedom in two dimensional strongly correlated systems. We establish a set of sufficient conditions for the occurence of spin and charge separation. Specifically, we discuss this issue in the context of the Heisenberg model for spin-1/2 on a square lattice with nearest ($J

Achille Giacometti, Hisao Nakanishi

We present a new finite-size scaling method for the random walks (RW) superseeding a previously widely used renormalization group approach, which is shown here to be inconsistent. The method is valid in any dimension and is based on the exact solution for the two-point correlation function and on finite size scaling. As an application, the phase diagram is d

Achille Giacometti, Amos Maritan

The statistics of equally weighted random paths (ideal polymer) is studied in $2$ and $3$ dimensional percolating clusters. This is equivalent to diffusion in the presence of a trapping environment. The number of $N$ step walks follows a log-normal distribution with a variance growing asymptotically faster than the mean which leads to a weak non self-averagi

Werner Ebeling, Thorsten Pöschel

Recently long range correlations were detected in nucleotide sequences and in human writings by several authors. We undertake here a systematic investigation of two books, Moby Dick by H. Melville and Grimm&#39;s tales, with respect to the existence of long range correlations. The analysis is based on the calculation of entropy like quantities as the mutual

Edmund Bertschinger

This paper reviews the essential physics of gravitational instability in a Robertson-Walker background spacetime. Three approaches are presented in a pedagogical manner, based on (1) the Eulerian fluid equations, (2) the Lagrangian description of trajectories, and (3) the Lagrangian fluid equations. Linear and nonlinear limits are discussed for each case. Sh

Leandros Perivolaropoulos

We propose a new test for distinguishing observationally cosmological models based on seed-like primordial perturbations (like cosmic strings or textures), from models based on Gaussian fluctuations. We investigate analytically the {\it Fourier space} statistical properties of temperature or density fluctuation patterns generated by seed-like objects and com

James F. Lynch

A random boolean cellular automaton is a network of boolean gates where the inputs, the boolean function, and the initial state of each gate are chosen randomly. In this article, each gate has two inputs. Let $a$ (respectively $c$) be the probability the the gate is assigned a constant function (respectively a non-canalyzing function, i.e., {\sc equivalence}

D. Louis- Martinez, J. Gegenberg, G. Kunstatter

The most general dilaton gravity theory in 2 spacetime dimensions is considered. A Hamiltonian analysis is performed and the reduced phase space, which is two dimensional, is explicitly constructed in a suitable parametrization of the fields. The theory is then quantized via the Dirac method in a functional Schrodinger representation. The quantum constraints

Miriam Leurer

We make a comprehensive study of indirect bounds on scalar leptoquarks that couple chirally and diagonally to the first generation by examining available data from low energy experiments as well as from high energy e+ e- and p pbar accelerators. The strongest bounds turn out to arise from low energy data: For leptoquarks that couple to right--handed quarks,

Damiano Anselmi

We consider the problem of removing the divergences in an arbitrary gauge-field theory (possibly nonrenormalizable). We show that this can be achieved by performing, order by order in the loop expansion, a redefinition of some parameters (possibly infinitely many) and a canonical transformation (in the sense of Batalin and Vilkovisky) of fields and BRS sourc

P. Bonche, E. Chabanat, B. Q. Chen, J. Dobaczewski

An overview of a microscopic framework based on the Hartree-Fock description of the mean field is presented which, starting from an effective interaction allows a description of collective motions. A study of the isotope shifts in the Pb region illustrates the importance of the effective interactions and points to their limitations. Such forces should be imp

Helmut Hofmann, Gert-Ludwig Ingold, Markus H. Thoma

The decay of a metastable system is described by extending Kramers&#39; method to the quantal regime. For temperatures above twice the crossover value we recover the result known from applying Euclidean path integrals to solvable models. Our derivation is not restricted to a linearly coupled heat bath of oscillators, and thus applicable to nuclear systems.

Jindřich Zapletal

Using elementary pcf, we show that there is no $j:V\to M,$ $M$ transitive, $jλ=λ>crit(j),$ $j^{\prime \prime}λ\in M.$

J. A. Gracey

The critical exponent corresponding to the renormalization of the composite operator $\barψψ$ is computed in quantum electrodynamics at $O(1/\Nf^2)$ in arbitrary dimensions and covariant gauge at the non-trivial zero of the $β$-function in the large $\Nf$ expansion and the exponent corresponding to the anomalous dimension of the electron mass which is a gaug

A. L. Larsen

We consider a macroscopic charge-current carrying (cosmic) string in the background of a Schwarzschild black hole. The string is taken to be circular and is allowed to oscillate and to propagate in the direction perpendicular to its plane (that is parallel to the equatorial plane of the black hole). Nurmerical investigations indicate that the system is non-i

Frank De Jonghe

We present a new collective field formalism with two rather than one collective field to derive the antifield formalism for extended BRST invariant quantisation. This gives a direct and physical proof of the scheme of Batalin, Lavrov and Tyutin, derived on algebraic grounds. The importance of the collective field in the quantisation of open algebras in both

Michael Flohr, Raimund Varnhagen

We have generalized recent results of Cappelli, Trugenberger and Zemba on the integer quantum Hall effect constructing explicitly a ${\cal W}_{1+\infty}$ for the fractional quantum Hall effect such that the negative modes annihilate the Laughlin wave functions. This generalization has a nice interpretation in Jain&#39;s composite fermion theory. Furthermore,

Gustavo Burdman, Zoltan Ligeti, Matthias Neubert, Yosef Nir

We present a systematic analysis of the $B^{(*)}\toπ\,\ell\,ν$ weak decay form factors to order $1/m_b$ in the heavy quark effective theory, including a discussion of renormalization group effects. These processes are described by a set of ten universal functions (two at leading order, and eight at order $1/m_b$), which are defined in terms of matrix element

M. Cvetic, F. del Aguila, P. Langacker

We present recent developments in the diagnostic study of heavy gauge bosons at future colliders with the emphasis on the determination of gauge couplings of $Z&#39;$ to quarks and leptons. Proposed diagnostic probes at future hadron colliders are discussed. The study of statistical uncertainties expected for the above probes at the LHC and $M_{Z&#39;}\simeq

James F. Amundson

I present a very simple model, based on the model of Isgur, Scora, Grinstein and Wise \cite{ISGW}, which can be used to calculate the effects which appear at subleading order in heavy quark effective theory. I include both general formalism and specific results. The formalism transparently reproduces the results of heavy quark effective theory, while giving

X. Zhang, B. -L. Young

A natural solution to the hierachy problem of the standard model is to assume new physics to appear at the TeV scale. We parametrize the effects of this new physics in terms of an effective lagrangian and examine its impacts on electroweak baryogenesis. We point out that with such an effective lagrangian successful electroweak baryogenesis implies: i) Higgs

G. Ecker

The hadronic sector of the standard model at low energies is described by a non--decoupling effective field theory, chiral perturbation theory. An introduction is given to the construction of effective chiral Lagrangians, both in the purely mesonic sector and with inclusion of baryons. The connection between the relativistic formulation and the heavy baryon

Taco Nieuwenhuis, J. A. Tjon, Yu. A. Simonov

In this work the Feynman-Schwinger representation for the two-body Greens function is studied. After having given a brief introduction to the formalism, we report on the first calculations based on this formalism. In order to demonstrate the validity of the method, we consider the static case where the mass of one of the particles becomes very large. We show

P. Zenczykowski

Quark and pole models of nonleptonic decays of charmed baryons are analysed from the point of view of their symmetry properties. The symmetry structure of the parity conserving amplitudes that corresponds to the contribution of the ground-state intermediate baryons is shown to differ from the one hitherto employed in the symmetry approach. It is pointed out

N. G. Antoniou, F. K. Diakonos, I. S. Mistakidis, C. G. Papadopoulos

Assuming a second-order phase transition for the hadronization process, we attempt to associate intermittency patterns in high-energy hadronic collisions to fractal structures in configuration space and corresponding intermittency indices to the isothermal critical exponent at the transition temperature. In this approach, the most general multidimensional in

W. Beirl, H. Markum, J. Riedler

We study quantum gravity in the path-integral formulation using the Regge calculus. In spite of the unbounded gravitational action the existence of an entropy-dominated phase is confirmed. The influence of various types of measures on this phase structure is investigated and our results are compared with those obtained by dynamical triangulation.

Hume A. Feldman, Richard Watkins

We follow a formalism presented by Kaiser to calculate the variance of bulk flows in large scale surveys. We apply the formalism to a mock survey of Abell clusters á la Lauer \& Postman and find the variance in the expected bulk velocities in a universe with CDM, MDM and IRAS--QDOT power spectra. We calculate the velocity variance as a function of the 1--D v

Arnaud Beauville, Yves Laszlo

Let M(r) be the moduli space of rank r vector bundles with trivial determinant on a Riemann surface X . This space carries a natural line bundle, the determinant line bundle L . We describe a canonical isomorphism of the space of global sections of L^k with a space known in conformal field theory as the ``space of conformal blocks&#34;, which is defined in t

Frederick T. Hawes, Craig D. Roberts, Anthony G. Williams

We study a model Dyson-Schwinger equation for the quark propagator closed using an {\it Ansatz} for the gluon propagator of the form \mbox{$D(q) \sim q^2/[(q^2)^2 + b^4]$} and two {\it Ans\"{a}tze} for the quark-gluon vertex: the minimal Ball-Chiu and the modified form suggested by Curtis and Pennington. Using the quark condensate as an order parameter, we f

P. D. Coddington

Revisions are almost entirely in the introduction and conclusion. Results are unchanged, however the comments and recommendations on different generators were changed, and more references were added.

Ray Carlberg

Velocity bias is a reduction of the velocity dispersion of tracer galaxies in comparison to the velocity dispersion of the underlying mass field. There are two distinct forms of velocity bias. The single particle velocity reduction, $b_v(1)$, is the result of energy loss of a tracer population, and in virialized regions, such as galaxy clusters, is intimatel

Kuo-Cheng Lee, Su-Long Nyeo

A non-principal value prescription is used to define the spurious singularities of Yang-Mills theory in the temporal gauge. Typical one-loop dimensionally-regularized temporal-gauge integrals in the prescription are explicitly calculated, and a regularization for the spurious gauge divergences is introduced. The divergent part of the one-loop self-energy is

Yi-Zhi Huang, James Lepowsky

This is the first part in a series of papers developing a tensor product theory for modules for a vertex operator algebra. The goal of this theory is to construct a ``vertex tensor category&#39;&#39; structure on the category of modules for a suitable vertex operator algebra. The notion of vertex tensor category is essentially a ``complex analogue&#39;&#39;

Fay Dowker, Jerome P. Gauntlett, David A. Kastor, Jennie Traschen

We consider dilaton gravity theories in four spacetime dimensions parametrised by a constant $a$, which controls the dilaton coupling, and construct new exact solutions. We first generalise the C-metric of Einstein-Maxwell theory ($a=0$) to solutions corresponding to oppositely charged dilaton black holes undergoing uniform acceleration for general $a$. We n

N. Cerf

We present a new combinatorial method for the calculation of the nuclear level density. It is based on a Monte Carlo technique, in order to avoid a direct counting procedure which is generally impracticable for high-A nuclei. The Monte Carlo simulation, making use of the Metropolis sampling scheme, allows a computationally fast estimate of the level density

R. Jackiw

Here is summarized the gauge theoretical formulation and quantization of two popular gravity theories in (1+1)-dimensional time.

J. -G. Demers

The symmetries of the topological Yang-Mills theory are studied in the Hamiltonian formalism and the generators of the twisted N=2 superPoincaré algebra are explicitly constructed. Noting that the twisted Lorentz generators do not generate the Lorentz symmetry of the theory, we relate the two by extracting from the latter the twisted version of the internal

F. Vanderseypen

We introduce a noncommutative calculus on the odd-symplectic superspace $\scri$ of fields and antifields. To this end we have to extend $\scri$ to $\exscri$ by including an extra anticommuting field $η$. As a consequence we show that the commutator induced on $\exnice\times T^\star(\exnice)$ is proportional to the antibracket. The $Δ$-operator is an element

H. Dorn, V. Preuss

Starting from the well-known expression for the trace anomaly we derive the $T\cdot T$ operator product expansion of the energy-momentum tensor in 2D conformal theories defined in the upper halfplane $without$ making use of the additional condition of no energy-momentum flux across the boundary. The OPE turns out to be the same as in the absence of the bound

A. Toon

The partition function of 2+1 Chern-Simons Witten topological gravity has an attractive interpretation in terms of the unbroken and broken phases of gravity. We make this physical interpretation manifest using the background field method.

Apoorva Patel

Feynman&#39;s path integrals provide a hidden variable description of quantum mechanics (and quantum field theories). The expectation values defined through path integrals obey Bell&#39;s inequalities in Euclidean time, but not in Minkowski time. This observation allows us to pinpoint the origin of violation of Bell&#39;s inequalities in quantum mechanics. %

L. Lavoura, Ling-Fong Li

We compute the oblique parameters, including the three new parameters $ V $, $ W $ and $ X $ introduced recently by the Montreal group, for the case of one scalar multiplet of arbitrary weak isospin $ J $ and weak hypercharge $ Y $. We show that, when the masses of the heaviest and lightest components of the multiplet remain constant, but $ J $ increases, th

Leandros Perivolaropoulos

We show analytically and numerically the existence of double vortex solutions in two-Higgs systems. These solutions are generalizations of the \no vortices and exist for all values of the parameters in the Lagrangians considered. We derive analytically the asymptotic behavior of the solutions and confirm it numerically by solving the field equations. Finally

C. A. Dominguez

An update is given of the determination of leptonic decay constants of charm and beauty mesons in the framework of relativistic Hilbert moments and Laplace transform QCD sum rules.

D. A. Morris, A. Ringwald

We report on a study of the potential of various cosmic ray physics experiments to search for Standard Model processes involving the nonperturbative production of O(30) weak gauge bosons. Whereas present and near-future experiments are insensitive to proton-induced processes, neutrino-induced processes give rise to promising signatures and rates in AMANDA, D

B. Grossman, Sourendu Gupta, U. M. Heller, F. Karsch

We investigate the finite-temperature excitation spectrum in the gluon sector of $SU(3)$ pure gauge theory through measurements of screening masses in correlations of loop operators. We develop the classification of such operators under the symmetry group of the `$z$-slice&#39;. In the confined phase of the theory, we find that the spectrum dynamically reali

T. Poeschel, V. Buchholtz

The static as well as the dynamic behaviour of granular material are determined by dynamic {\it and} static friction. There are well known methods to include static friction in molecular dynamics simulations using scarcely understood forces. We propose an Ansatz based on the geometrical shape of nonspherical particles which does not involve an explicit expre

Ian Redmount, Wai-Mo Suen

A simple spacetime wormhole, which evolves classically from zero throat radius to a maximum value and recontracts, can be regarded as one possible mode of fluctuation in the microscopic ``spacetime foam&#39;&#39; first suggested by Wheeler. The dynamics of a particularly simple version of such a wormhole can be reduced to that of a single quantity, its throa

Peter Anninos, David Hobill, Edward Seidel, Larry Smarr

We study the head-on collision of two equal mass, nonrotating black holes. We consider a range of cases from holes surrounded by a common horizon to holes initially separated by about $20M$, where $M$ is the mass of each hole. We determine the waveforms and energies radiated for both the $\ell = 2$ and $\ell=4$ waves resulting from the collision. In all case

Edward Seidel, Wai-Mo Suen

We studied the formation of compact bosonic objects through a dissipationless cooling mechanism. Implications of the existence of this mechanism are discussed, including the abundance of bosonic stars in the universe, and the possibility of ruling out the axion as a dark matter candidate.

J. M. Aguirregabiria, A. Feinstein, J. Ibanez

We obtain exact solutions for the Einstein equations with an exponential-potential scalar field (\(V=Λe^{kϕ}\)) which represent simple inhomogeneous generalizations of Bianchi I cosmologies. Studying these equations numerically we find that in most of the cases there is a certain period of inflationary behaviour for \(k^2<2\). We as well find that for \(k^2>