June 1994 arXiv papers — page 6

A. Erdas, C. W. Kim, J. A. Lee

We calculate the generational mass splitting of neutrinos in high temperature $SU(2)_{\scriptscriptstyle{L}}\otimes U(1)$ gauge theory when the temperature is above $250$ GeV and the gauge symmetry is restored. We consider the case of neutrinos that are massless at tree level as well as the case of neutrinos with tree-level mass and large mixing.

F. Halzen, J. E. Jacobsen

High energy neutrinos are produced by the annihilation of dark matter particles in our galaxy. These are presently searched for with large area, deep underground neutrino telescopes. Cold dark matter particles, trapped inside the sun, are an abundant source of such neutrinos. Back-of-the-envelope calculations are sufficient to demonstrate how neutrino telesc

O. Philipsen

The dynamical generation of a transverse gauge field mass is studied by means of gap equations for pure gauge theory and the gauged non-linear sigma model in three dimensions. Non-trivial solutions to the gap equations are found indicating that this type of mass generation is a feature of the static sector of finite temperature field theory. In the case of t

Yue-Liang Wu

In this talk I will show that the two-Higgs doublet model with vacuum CP violation and approximate global $U(1)$ family symmetries may provide one of the simplest and most attractive models for understanding the origin and mechanisms of CP violation. It is shown that the mechanism of spontaneous symmetry breaking provides not only a mechanism for generating

J. Segura, J. Bernabéu, F. J. Botella, J. A. Peñarrocha

A novel method to look for neutrino oscillations is proposed based on the elastic scattering process $\barν_{i} e^{-}\rightarrow \barν_{i} e^{-}$, taking advantage of the dynamical zero present in the differential cross section for $\barν_{e} e^{-}\rightarrow \barν_{e} e^{-}$. An effective tunable experiment between the "appearance" and "disappea

Tomislav Prokopec

Baryon asymmetry can be generated at the first order electroweak phase transition, provided there is a CP violation on the bubble wall. In this report we discuss the role of leptons and quarks in the `non-local' baryogenesis mechanism.

J. L. Hewett

The radiative decay b to s gamma is examined in the Standard Model and in nine classes of models which contain physics beyond the Standard Model. The constraints which may be placed on these models from the recent results of the CLEO Collaboration on both inclusive and exclusive radiative $B$ decays is summarized. Reasonable bounds are found for the paramete

J. S. F. Chan, R. B. Mann

We investigate the phenomenon of mass inflation in two-dimensional dilaton theories of gravity. We consider two distinct black hole spacetimes and construct the mass-inflation solution for each. Our analysis is extended to include multi-horizon spacetimes. We find that the mass function diverges in a manner quantitatively similar to its four-dimensional coun

Takahiro TANAKA, Misao SASAKI

We extend our previous analysis of the quantum state during and after $O(4)$-symmetric bubble nucleation to the case including gravitational effects. We find that there exists a simple relationship between the case with and without gravitational effects. In a special case of a conformally coupled scalar field which is massless except on the bubble wall, the

A. Connes, C. Rovelli

We consider the cluster of problems raised by the relation between the notion of time, gravitational theory, quantum theory and thermodynamics; in particular, we address the problem of relating the "timelessness" of the hypothetical fundamental general covariant quantum field theory with the "evidence" of the flow of time. By using the algebr

Dirk Jan Bukman, Joel D. Shore

We examine the last unexplored regime of the asymmetric six-vertex model: the low-temperature phase of the so-called ferroelectric model. The original publication of the exact solution, by Sutherland, Yang, and Yang, and various derivations and reviews published afterwards, do not contain many details about this regime. We study the exact solution for this m

Z. N. C. Ha, F. D. M. Haldane

We identify exact excitation content of the intermediate states for the one-particle Green's functions, spin-spin and (charge) density-density correlation functions of the periodic one-dimensional $t$-$J$ model with inverse square exchange. The excitations consist of neutral $S=1/2$ spinons and spinless (charge $-e$) holons with semionic fractional stati

J. J. Palacios, L. Martin-Moreno, G. Chiappe, E. Louis

A theoretical study of single electron capacitance spectroscopy in quantum dots is presented. Exact diagonalizations and the unrestricted Hartree-Fock approximation have been used to shed light over some of the unresolved aspects. The addition spectra of up to 15 electrons is obtained and compared with the experiment. We show evidence for understanding the d

Alex Kamenev, Yuval Gefen

We study the conductance (g) distribution function of an ensemble of isolated conducting rings, with an Aharonov--Bohm flux. This is done in the discrete spectrum limit, i.e., when the inelastic rate, frequency and temperature are all smaller than the mean level spacing. Over a wide range of g the distribution function exhibits universal behavior P(g)\sim g^

Mark Srednicki

We briefly review the well known connection between classical chaos and classical statistical mechanics, and the recently discovered connection between quantum chaos and quantum statistical mechanics.

D. Z. Liu, H. A. Fertig, S. Das Sarma

We develop a method to compute shakeup effects on photoluminescence in a Wigner crystal from localized holes. Our method treats the lattice electrons and the tunneling electron on an equal footing, and uses a quantum-mechanical calculation of the collective modes that is realistic throughout the Brillouin zone. We find that shakeup produces a series of sideb

Fernando Sánchez León

This working paper describes the Spanish tagset to be used in the context of CRATER, a CEC funded project aiming at the creation of a multilingual (English, French, Spanish) aligned corpus using the International Telecommunications Union corpus. In this respect, each version of the corpus will be (or is currently) tagged. Xerox PARC tagger will be adapted to

A. Mezhlumian, A. Starobinsky

This is an old article which has never been posted for public use and which only appeard in a relatively hard-to-get Proceedings of the Sakharov Conference in Moscow (May, 1991). The subject of this article has received a lot of attention in last two years. Although we acknowledge that there has been a very big progress in the field of relating the spectrum

Chris Mihos, Lars Hernquist

We have incorporated star formation algorithms into a hybrid N-body/smoothed particle hydrodynamics code (TREESPH) in order to describe the star forming properties of disk galaxies over timescales of a few billion years. The models employ a Schmidt law of index $n\sim 1.5$ to calculate star formation rates, and explicitly include the energy and metallicity f

Gary A. Mamon

\def\spose#1{\hbox to 0pt{#1\hss}} \def\lta{\mathrel{\spose{\lower 3pt\hbox{$\mathchar"218$}} \raise 2.0pt\hbox{$\mathchar"13C$}}} Groups of galaxies are highly linked to cosmology: 1) groups are tidally destroyed by the tidal field of the cluster they fall into; 2) spherical infall leads to the young cosmo-dynamical state of loose groups, a fundamen

A. Ulmer, J. Goodman

Femtolensing is a gravitational lensing effect in which the magnification is a function not only of the positions and sizes of the source and lens, but also of the wavelength of light. Femtolensing is the only known effect of $(10^{-13}-10^{-16} M_{\sun})$ dark-matter objects and may possibly be detectable in cosmological gamma-ray burst spectra. We present

Marco Frasca

We discuss a possible approach to the problem of a gauge theory with a strong coupling constant. It is seen that, instead of plane waves, we have to consider the adiabatic eigenstates of the perturbation in order to get a meaningful perturbation approach.

Patrick Huet

Electroweak baryogenesis is addressed within the context of the standard model of particle physics. Although the minimal standard model has the means of fulfilling the three Sakharov's conditions, it falls short to explaining the making of the baryon asymmetry of the universe. In particular, it is demonstrated that the phase of the CKM mixing matrix is a

L. F. Cugliandolo, J. Kurchan, G. Parisi

We analyse the Langevin dynamics of the random walk, the scalar field, the X-Y model and the spinoidal decomposition. We study the deviations from the equilibrium dynamics theorems (FDT and homogeneity), the asymptotic behaviour of the systems and the aging phenomena. We compare the results with the dynamical behaviour of (random) spin-glass mean-field model

Freddy Christiansen, Hans Henrik Rugh, Svend Erik Rugh

We comment on an analysis by Contopoulos et al. which demonstrates that the governing six-dimensional Einstein equations for the mixmaster space-time metric pass the ARS or reduced Painlevé test. We note that this is the case irrespective of the value, $I$, of the generating Hamiltonian which is a constant of motion. For $I < 0$ we find numerous closed orbit

Helia Hollmann

The behaviour of magnetic monopole solutions of the Einstein-Yang-Mills-Higgs equations subject to linear spherically symmetric perturbations is studied. Using Jacobi&#39;s criterion some of the monopoles are shown to be unstable. Furthermore the numerical results and analytical considerations indicate the existence of a set of stable solutions.

Eamonn J. Kerins

Four microlensing collaborations are presently searching for compact matter in the Galaxy and all have detected possible candidates. Using the detection efficiencies recently published by the MACHO and OGLE collaborations, we present Monte-Carlo calculations of the expected optical depth, rates and timescales, along the LMC and Galactic bulge lines of sight,

Clifford V. Johnson, Robert C. Myers

Starting with the Taub--NUT solution to Einstein&#39;s equations, together with a constant dilaton, a dyonic Taub--NUT solution of low energy heterotic string theory with non--trivial dilaton, axion and $U(1)$ gauge fields is constructed by employing $O(1,1)$ transformations. The electromagnetic dual of this solution is constructed, using $SL(2,\rline)$ tran

M. Asakawa, C. M. Ko

In a previous paper, we have shown that a double phi peak structure appears in the dilepton invariant mass spectrum if a first order QCD phase transition occurs in ultrarelativistic heavy ion collisions. Furthermore, the transition temperature can be determined from the transverse momentum distribution of the low mass phi peak. In this work, we extend the st

J. Ryckebusch, V. Van der Sluys, M. Waroquier, L. J. H. M. Kester

The contributions from $^{12}$C$(e,e&#39;pn)$ and $^{12}$C$(e,e&#39;pp)$ to the semi-exclusive $^{12}$C$(e,e&#39;p)$ cross section have been calculated in an unfactorized model for two-nucleon emission. We assume direct two-nucleon knockout after virtual photon coupling with the two-body pion-exchange currents in the target nucleus. Results are presented at

Josef Sollfrank, Ulrich Heinz

We investigate the thermal behaviour of gluon and chiral condensates within an effective Lagrangian of pseudoscalar mesons coupled to a scalar glueball. This Lagrangian mimics the scale and chiral symmetries of QCD. (Submitted to Z. Phys. C)

M. B. Halpern, N. Sochen

Following the paradigm on the sphere, we begin the study of irrational conformal field theory (ICFT) on the torus. In particular, we find that the affine-Virasoro characters of ICFT satisfy heat-like differential equations with flat connections. As a first example, we solve the system for the general $g/h$ coset construction, obtaining an integral representa

D. Minic, V. P. Nair

We analyze the renormalization of wave functionals and energy eigenvalues in field theory. A discussion of the structure of the renormalization group equation for a general Hamiltonian system is also given.

V. P. Nair

We consider the hard thermal loops of QCD for a moving quark-gluon plasma. Generalizing from this we suggest a candidate for the magnetic mass term. This term may also be useful in understanding the mass gap of three-dimensional non-Abelian gauge theories.

E. Ramos, J. Roca

We show that W_3 is the algebra of symmetries of the ``rigid-particle&#39;&#39;, whose action is given by the integrated extrinsic curvature of its world line. This is easily achived by showing that its equation of motion can be written in terms of the Boussinesq operator. We also show how to obtain the equations of motion of the standard relativistic partic

E. Ivanov, E. Sokatchev

We propose an action describing chiral fermions with an arbitrary gauge group and with manifest $(8,0)$ worldsheet supersymmetry. The form of the action is inspired by and adapted for completing the twistor-like formulation of the $D=10$ heterotic superstring.

S. J. Hyun, G. H. Lee, J. H. Yee

The (2+1)-dimensional Thirring model is studied by using the Gaussian approximation method in the functional Schrödinger picture. Although the dynamical symmetry breaking does not occur in the large N limit, it does occur in the Gaussian approximation which includes the higher order contributions in 1/N.

A. J. Niemi, K. Palo

We investigate an equivariant generalization of Morse theory for a general class of integrable models. In particular, we derive equivariant versions of the classical Poincaré-Hopf and Gauss-Bonnet-Chern theorems and present the corresponding path integral generalizations. Our approach is based on equivariant cohomology and localization techniques, and is clo

Patrick J. O&#39;Donnell, Q. P. Xu

We use the relativistic light--front quark model to show that both strong and radiative $D^\ast$ decays are in good agreement with the 1992 CLEO II results. In particular the coupling for $D^{\ast}\ra D π$ is consistent with the experimental upper limit. The key point is the relativistic treatment of the quark spin.

K. G. Chetyrkin, J. H. Kühn

The influence of nonvanishing quark masses on the total cross section in electron positron collisions and on the $Z$ decay rate is calculated. The corrections are expanded in $m^2/s$ and $\as$. Methods similar to those applied for the quadratic mass terms allow to derive the corrections of order $\as m^4/s^2$ and $\as^2m^4/s^2$. Coefficients which depend log

P. F. Kelly, R. Kobes, G. Kunstatter

We examine the calculation of the critical temperature $T_c$ for the restoration of a spontaneously broken symmetry. Motivated by a set of recently developed gauge dependence identities, we give a gauge and parameterization independent definition of this temperature in terms of the physical mass of the scalar particle as determined by the propagator pole. As

R. J. Rivers

We use the closed time-path formalism to calculate fluctuations at phase transitions, both in and out of equilibrium. Specifically, we consider the creation of vortices by fluctuations, of relevance to the early universe and to $^{4}He$ superfluidity. (Invited talk to Nato Advanced Research Workshop on Electroweak Physics and the Early Universe, Sintra (Port

Jihn E. Kim, Hans Peter Nilles

We stress that a natural solution of the $μ$ problem requires two ingredients: a symmetry that would enforce $μ= 0$ as well as the occurence of a small breaking parameter that generates a nonzero $μ$. It is suggested that both the Peccei-Quinn symmetry and the spontaneously broken $R$ symmetry may be the sources of the needed $μ$ term in the minimal supersym

P. Colangelo, A. Deandrea, N. Di Bartolomeo, F. Feruglio

We compute the strong coupling constant $g_{P^* P π}$, with $P$ and $P^*$ respectively pseudoscalar and vector heavy mesons by using the QCD sum rules approach. Our computation is based on the evaluation of the time ordered product of currents between the vacuum and the soft pion state. The so-called parasitic terms are taken into account and give a contribu

Levan R. Surguladze

A short presentation of the results of the analytical evaluation of the O(α_s^2) QCD contributions in the fermionic decay rates of the neutral CP-odd minimal supersymmetric Higgs particle is made. The corrections due to the nonvanishing quark masses are included. The results are presented both in terms of running and pole quark masses.

Frithjof Karsch, Edwin Laermann

We study the quark mass dependence of various response functions, which contribute to chiral susceptibilities and the specific heat in the staggered fermion formulation of two-flavour QCD. This yields information about the critical exponents $α$, $β$ and $δ$. In the case of the chiral susceptibility, obtained as derivative of the chiral order parameter with

I. Vattulainen, T. Ala-Nissila, K. Kankaala

We propose three physical tests to measure correlations in random numbers used in Monte Carlo simulations. The first test uses autocorrelation times of certain physical quantities when the Ising model is simulated with the Wolff algorithm. The second test is based on random walks, and the third on blocks of n successive numbers. We apply the tests to show th

Karsten Flensberg, Ben Yu-Kuang Hu

We show theoretically that the Coulomb drag rate between two parallel quasi-two-dimensional electron gases is substantially enhanced by the coupled acoustic and optic plasmon modes of the system at temperatures $T \gtrsim 0.2T_F$ (where $T_F$ is the Fermi temperature) for experimentally relevant parameters. The acoustic mode causes a sharp upturn in the scal

A. Crisanti, H. -J. Sommers

In this letter we analyze the TAP approach to the spherical $p$-spin spin glass model in zero external field. The TAP free energy is derived by summing up all the relevant diagrams for $N\to\infty$ of a diagrammatic expansion of the free energy. We find that if the multiplicity of the TAP solutions is taken into account, then there is a first order transitio

T. Garel, L. Leibler, H. Orland

We study a single statistical amphiphilic copolymer chain AB in a selective solvent (e.g.water). Two situations are considered. In the annealed case, hydrophilic (A) and hydrophobic (B) monomers are at local chemical equilibrium and both the fraction of A monomers and their location along the chain can vary, whereas in the quenched case (which is relevant to

Kim Binsted, Graeme Ritchie

In this paper, we discuss a model of simple question-answer punning, implemented in a program, JAPE, which generates riddles from humour-independent lexical entries. The model uses two main types of structure: schemata, which determine the relationships between key words in a joke, and templates, which produce the surface form of the joke. JAPE succeeds in g

Kim Binsted, Graeme Ritchie

Riddles based on simple puns can be classified according to the patterns of word, syllable or phrase similarity they depend upon. We have devised a formal model of the semantic and syntactic regularities underlying some of the simpler types of punning riddle. We have also implemented this preliminary theory in a computer program which can generate riddles fr

Renu Malhotra

Orbital resonances are ubiquitous in the Solar system. They play a decisive role in the long term dynamics, and in some cases the physical evolution, of the planets and of their natural satellites, as well as the evolution of small bodies (including dust) in the planetary system. The few-body gravitational problem of hierarchical planetary-type systems allow

G. Comer Duncan, Philip A. Hughes

We describe a method for the numerical solution of the relativistic Euler equations which we have found to be both robust and efficient, and which has enabled us to simulate relativistic jets. The technique employs a solver of the Godunov-type, with approximate solution of the local Riemann problems, applied to laboratory frame variables. Lorentz transformat

John N. Bahcall, Ami Glasner

Predicted rates for solar neutrino experiments that are obtained with a modified stellar evolution code originally developed to study the advanced stages of stellar evolution are shown to be in agreement with other recently-calculated precise solar models to about 2% (0.2 SNU for the chlorine experiment). Different scenarios for pre-main sequence evolution a

M. A. Strauss, R. Cen, J. P. Ostriker, T. R. Lauer

Lauer \& Postman (LP) observe that all Abell clusters with redshifts less than 15,000\kms\ appear to be participating in a bulk flow of 689 km s$^{-1}$ with respect to the Cosmic Microwave Background. We find this result difficult to reconcile with all popular models for large-scale structure formation that assume Gaussian initial conditions. This conclusion

G. Giovannini, L. Feretti, T. Venturi, L. Lara

We present here new VLBI observations of one FR-I radio galaxy (NGC2484) and two Broad Line FR-II radio galaxies (3C109 and 3C382). For 3C109 new VLA maps are also shown. These sources belong to a complete sample of radio galaxies under study for a better knowledge of their structures at parsec resolution. The parsec structure of these 3 objects is very simi

Xiang-Ping Wu

The mass derived from gravitational lensing reflects the total mass contained in the lensing system, independent of the specific matter contents and states. A comparison of the dynamical masses from hydrostatic equilibrium with the gravitational masses from arc-like images of background galaxies is made for four clusters of galaxies at intermediate redshits.

Andrei Tyurin

The paper is a colloquial-style discussion of invariants of algebraic surfaces analogous to the Donaldson polynomials, arising from moduli spaces of ``jumping&#39;&#39; Yang--Mills instantons, or moduli spaces of jumping vector bundles. The invariants have the following applications: (1) to the Van de Ven conjecture that the Kodaira dimension is a diffeomorp

Dan-di WU, Zhi-zhong XING

The unitarity triangles of the $3\times 3$ Cabibbo-Kobayashi-Maskawa (CKM) matrix are studied in a systematic way. We show that the phases of the nine CKM rephasing invariants are indeed the outer angles of the six unitarity triangles and measurable in the $CP$-violating decay modes of $B_{d}$ and $B_{s}$ mesons. An economical notation system is introduced f

Zhi-zhong Xing

Considering that the existing experimental limit for $CPT$ violation is still poor, we explore various possible ways to test $CPT$ symmetry in $CP$-violating $B$ decays at $e^{+}e^{-}$ $B$ factories and hadron machines. We find that it is difficult to distinguish between the effect of direct $CP$ violation and that of $CPT$ violation in the time-integrated m

Kenichiro Aoki, Santiago Peris

We compute the large-$m_t$ contributions to the $Zb\overline b$ vertex in the Standard Model non-perturbatively using both the $1/\nc$ and the $1/\nf$ expansions. Triviality and its consequences for the perturbative result are systematically analyzed. In particular, we point out that the effect of triviality is already important at the two-loop level for a h

M. B. Gavela, P. Hernandez, J. Orloff, O. Pène

We consider the scattering of quasi-particles off the boundary created during a first order electroweak phase transition. Spatial coherence is lost due to the quasi-quark damping rate, and we show that reflection on the boundary is suppressed, even at tree-level. Simply on CP considerations, we argue against electroweak baryogenesis in the Standard Model via

H. Fritzsch, D. Wu, Z. Xing

Within the standard model we carry out an analysis of $CP$-violating observables in neutral $B$-meson decays at the $Υ(4S)$ resonance. Both time-dependent and time-integrated $CP$ asymmetries are calculated, without special approximations, to meet various possible measurements at symmetric and asymmetric $e^{+}e^{-}$ $B$ factories. We show two ways to distin

G. T. Horowitz, A. A. Tseytlin

We construct two new classes of exact solutions to string theory which are not of the standard plane wave or gauged WZW type. Many of these solutions have curvature singularities. The first class includes the fundamental string solution, for which the string coupling vanishes near the singularity. This suggests that the singularity may not be removed by quan

Yukari Ito

The purpose of this paper is to construct a crepant resolution of quotient singularities by finite subgroups of SL(3,C) of monomial type, and prove that the Euler number of the resolution is equal to the number of conjugacy classes. This result is a part of conjecture II in previous paper &#34;Crepant resolution of trihedral singularities&#34; (alg-geom 9404

Sandip K. Chakrabarti, Diego Molteni

We study the evolution of viscous, isothermal, rotating, thin, axisymmetric accretion disks around a compact object using Smoothed Particle Hydrodynamics. We emphasize the effects of different choices of viscosity prescriptions on the evolution of angular momentum as well as other physical quantities of the disk. We show that a flow with the Shakura-Sunyaev

Ron Perline

We describe a close connection between the localized induction equation hierarchy of integrable evolution equations on space curves, and surfaces of constant negative Gauss curvature.

M. B. Gavela, M. Lozano, J. Orloff, O. Pène

We consider quantum effects in a world with two coexisting symmetry phases, unbroken and spontaneously broken, as a result of a first order phase transition. The discrete symmetries of the problem are discussed in general. We compute the exact two-point Green function for a free fermion, when a thin wall separates the two phases. The Dirac propagator display

Yu-Qi Chen, Yu-Ping Kuang, Robert J. Oakes

A new formula for the heavy quark-antiquark spin dependent potential is given by using the techniques developed in the heavy quark effective theory. The leading logarithmic quark mass terms emerging from the loop contributions are explicitly extracted and summed up. There is no renormalization scale ambiguity in this new formula. The spin-dependent potential

H. Anlauf

We reinvestigate the leading QCD corrections to the radiative decay $b \to s γfor supersymmetric extensions of the Standard Model. Although the major contributions to the corrections originate from the running of the effective Lagrangian from the W scale down to the $b$ scale, additional corrections are expected from large mass splittings between the particl

S. C. Woon

Voronin&#39;s theorem on the `Universality&#39;&#39; of Riemann zeta function is shown to imply that Riemann zeta function is a fractal (in the sense that Mandelbrot set is a fractal) and a concrete ``representation&#39;&#39; of the ``giant book of theorems&#39;&#39; that Paul Halmos referred to.

August E. Evrard

The degree of complexity and, to a somewhat lesser degree, realism in simulations has advanced rapidly in the past few years. The simplest approach - modeling a cluster as collisionless dark matter and collisonal, non--radiative gas is now fairly well established. One of the most fruitful results of this approach is the {\sl morphology--cosmology connection}

Renu Malhotra

About two years ago, Wolszczan and Frail announced the detection of a possible planetary system consisting of two Earth-mass planets around a millisecond pulsar. It was pointed out shortly thereafter that the mutual gravitational interaction of the planets leads to predictable evolution of their orbits. Because millisecond pulsars are very stable ``clocks&#3

Ivan T. Ivanov, Byungbae Kim, Martin Rocek

We find the complex structure on the dual of a complex target space. For $N=(2,2)$ systems, we prove that the space orthogonal to the kernel of the commutator of the left and right complex structures is {\em always} integrable, and hence the kernel is parametrized by chiral and twisted chiral superfield coordinates. We then analyze the particular case of $SU

H. Leutwyler

Lectures given at the Workshop &#34;Hadrons 1994&#34;, Gramado, RS, Brasil

S. Peigné, S. M. H. Wong

We study the non-abelian, gauge invariant, screening potential between two charges in a quark-gluon plasma. Using Braaten and Pisarski resummed perturbation theory in temporal axial gauge, we find a repulsive power screened potential which behaves as $\sim 1/r^6$ at large distance. This questions either the physical meaning of the Debye mass or the known pra

I. Peschel, V. Rittenberg, U. Schultze

We study one-dimensional reaction-diffusion models described by master equations and their associated two-state quantum Hamiltonians. By choosing appropriate rates, the equations of motion decouple into certain subsets. We solve the first subset which has a close relation to the problem of lattice electrons in an electric field. In this way we obtain $L (L -

Rolf Backofen, Gert Smolka

Various feature descriptions are being employed in logic programming languages and constrained-based grammar formalisms. The common notational primitive of these descriptions are functional attributes called features. The descriptions considered in this paper are the possibly quantified first-order formulae obtained from a signature of binary and unary predi

T. R. Werner, J. A. Sheikh, W. Nazarewicz, M. R. Strayer

Masses, deformations, radii, and single-particle properties of the very neutron-rich Sulfur isotopes are investigated in the framework of the selfconsistent mean-field theory. The stability of the N=28 magic gap around $^{44}$S is discussed.

W. Dieter Heiss, Rashid G. Nazmitdinov, Stefanel Radu

Classical and quantum mechanical results are reported for the single particle motion in a harmonic oscillator potential which is characterized by a quadrupole deformation and an additional octupole deformation. The chaotic character of the motion is srongly dependent on the quadrupole deformation in that for a prolate deformation virtually no chaos is discer

A. N. Mitra, K. -C. Yang

The momemtum dependence of the off-shell $ρ$-$ω$ mixing amplitude is calculated through a two-quark loop diagram, using non-perturbative meson-quark vertex functions for the $ρ$ and $ω$ mesons, as well as non-perturbative quark propagators. Both these quantities are generated self-consistently through an interlinked BSE-cum-SDE approach with a 3D support for

T. D. Palev

The algebraic structure of the Green&#39;s ansatz is analyzed in such a way that its generalization to the case of q-deformed para-Bose and para-Fermi operators is becoming evident. To this end the underlying Lie (super)algebraic properties of the parastatistics are essentially used.

Louis H. Kauffman, David E. Radford

This paper studies invariants of 3-manifolds derived from certain fin ite dimensional Hopf algebras. The invariants are based on right integrals for these algebras. It is shown that the resulting class of invariants is distinct from the class of Witten-Reshetikhin-Turaev invariants.

Marc de Montigny

We apply Kac&#39;s theory of elements of finite order (EFO) in Lie groups to the description of discrete gauge symmetries in various supersymmetric grand unified models. Taking into account the discrete anomaly cancellation conditions, we identify the EFO which generate certain matter parities in the context of the supersymmetric $SO(10)$ and $E_6$ models.

Byungbae Kim, Ulf Lindström, Martin Roček

Using a reformulation of the nonlinear multiplet as a gauge multiplet, we discuss its dynamics. We show that the nonlinear ``duality&#39;&#39; that appears to relate the model to a conventional $σ$-model introduces a new sector into the theory.

Brian P. Dolan

It is argued that renormalisation group flow can be interpreted as being a Hamiltonian vector flow on a phase space which consists of the couplings of the theory and their conjugate \lq\lq momenta&#34;, which are the vacuum expectation values of the corresponding composite operators. The Hamiltonian is linear in the conjugate variables and can be identified

Renata Kallosh, David Kastor, Tomas Ortin, Tibor Torma

New stationary solutions of $4$-dimensional dilaton-axion gravity are presented, which correspond to the charged Taub-NUT and Israel-Wilson-Perjes (IWP) solutions of Einstein-Maxwell theory. The charged axion-dilaton Taub-NUT solutions are shown to have a number of interesting properties: i) manifest $SL(2,R)$ symmetry, ii) an infinite throat in an extremal

P. F. Kelly, Q. Liu, C. Lucchesi, C. Manuel

Classical transport theory for colored particles is investigated and employed to derive the hard thermal loops of QCD. A formal construction of phase-space for color degrees of freedom is presented. The gauge invariance of the non-Abelian Vlasov equations is verified and used as a guiding principle in our approximation scheme.We then derive the generating fu

M. I. Gorenstein, H. G. Miller, R. M. Quick, R. A. Ritchie

We study the energy-momentum and baryonic number conservation laws for quark-gluon plasma discontinuity transitions into hadron matter states. We find that the time-like shock hadronization of a supercooled quark-gluon plasma (when the normal vector to the discontinuity hypersurface is time-like) should take place. We consider some properties of this process

R. Sekhar Chivukula, Michael J. Dugan, Mitchell Golden

We show that it is possible to construct models in which the width of the Higgs boson is arbitrary - either smaller or larger than a standard model Higgs boson of the same mass. There are no new fields into which the Higgs boson decays. Instead, the coupling of the Higgs boson to the gauge bosons is adjusted. We construct and analyze weakly--coupled models w

Marco Aurelio Diaz

Minimal $N=1$ supergravity with a radiatively broken electroweak symmetry group is studied in the light gluino scenario. Constraints from the $b\rightarrow sγ$ decay and from the masses of the light CP-even neutral Higgs $m_h$, the lightest chargino $m_{χ^{\pm}_1}$, and the second lightest neutralino $m_{χ^0_2}$ are analyzed. We consider models in which the

Junegone CHAY, Soo-Jong REY

We study instanton effects on $B \rightarrow X_sγ$ decay using the heavy quark effective field theory and the operator product expansion. In the dilute gas approximation the effect is negligibly small. This is in contrast to the result of the instanton effect in inclusive semileptonic $b\rightarrow u$ decay but similar to the inclusive hadronic $τ$ decay. We

Stephen Godfrey

I review some outstanding issues in meson spectroscopy. The most important qualitative issue is whether hadrons with explicit gluonic degrees of freedom exist. To answer this question requires a much better understanding of conventional $q\bar{q}$ mesons. I therefore begin by examining the status of conventional meson spectroscopy and how the situation can b

Edmond Iancu

Because of the long range of the gauge interactions, the collective behaviour of quarks and gluons plays a decisive role in the transport processes. Collective effects, like Debye screening and Landau damping, remove the unphysical infrared divergences of the transport cross-sections and provide finite relaxation rates. I review here a theory of the plasma c

E. V. Prokhvatilov, H. W. L. Naus, H. --J. Pirner

We introduce a new method to include condensates in the light-cone Hamiltonian. By using a Gaussian approximation to the ordinary vacuum in a theory close to the light front, we derive an effective Hamiltonian on the light cone, which has new terms reflecting the nontriviality of the vacuum. We demonstrate our method for scalar $ϕ^4$-theory and the massive S

Dirk Graudenz

The one-particle inclusive cross section in deeply inelastic lepton--nucleon scattering, expressed in terms of parton densities and fragmentation functions being differential in the invariant mass of the observed hadron and of the incoming nucleon, diverges if this invariant mass vanishes. This divergence can be traced back to the kinematical configuration w

D. Bardin, A. Leike, T. Riemann

The cross-section for the reaction $e^+e^- \rightarrow b\bar{b}μ^+μ^-$ is calculated with a semi-analytical integration of the phase space. Compact formulae are obtained for the total cross section and for invariant mass distributions of the $μ^+μ^-$ and $b\bar{b}$ pairs. The background diagrams to $ZH$ production yield analytically cumbersome but numericall

A. J. Buras

We review the present status of CP violation in the standard model. Subsequently we make an excursion in the future in order to see what we could expect in this field in this and the next decade. We present various strategies for the determination of the CKM parameters and divide the decays into four classes with respect to theoretical uncertainties. We emph

Shoji Hashimoto, Jiro Kodaira, Yoshiaki Yasui, Ken Sasaki

We show that the background field method (BFM) is a simple way of deriving the same gauge-invariant results which are obtained by the pinch technique (PT). For illustration we construct gauge-invariant self-energy and three-point vertices for gluons at one-loop level by BFM and demonstrate that we get the same results which were derived via PT. We also calcu