September 1994 arXiv papers — page 2

D. V. Khveshchenko

We discuss an approach to higher dimensional bosonization of interacting fermion s based on a picture of fluctuating Fermi surface. Compared with the linearized"constructive" approach developed in Refs.[9-11] this method allows an account of the Fermi surface curvature due to nongaussian terms in the bosonized Lagrangian. On the basis of this descrip

A. Klümper, S. I. Matveenko, J. Zittartz

New exactly solvable nineteen vertex models and related quantum spin-1 chains are solved. Partition functions, excitation energies, correlation lengths, and critical exponents are calculated. It is argued that one of the non-critical Hamiltonians is a realization of an integrable Haldane system. The finite-size spectra of the critical Hamiltonians deviate in

J. Diehl, H. Davideit, S. Klimm, S. Horn

Measurements of electrical resistivity and Hall effect as a function of magnetic field on the Heavy Fermion Systems YbNiAl and YbPtAl are presented. Both compounds order antiferro magnetically and show metamagnetic behavior in a magnetic field. Scaling behavior of the magnetoresistance above TN suggests that the paramagnetic regime for YbNiAl can be describe

Marc Dymetman, Julie Brousseau, George Foster, Pierre Isabelle

Professional translators often dictate their translations orally and have them typed afterwards. The TransTalk project aims at automating the second part of this process. Its originality as a dictation system lies in the fact that both the acoustic signal produced by the translator and the source text under translation are made available to the system. Proba

Henry C. Ferguson, Bruno Binggeli

Dwarf elliptical (dE) galaxies, with blue absolute magnitudes typically fainter than $M_B = -16$, are the most numerous type of galaxy in the nearby universe. Tremendous advances have been made over the past several years in delineating the properties of both Local Group satellite dE's and the large dE populations of nearby clusters. We review some of th

G. Vettolani, E. Zucca, A. Cappi, R. Merighi

We present the first results of a galaxy redshift survey, ESO Slice Project (ESP), we are accomplishing as an ESO Key-Project over about 30 square degrees in a region near the South Galactic Pole. The limiting magnitude is b_J = 19.4. Observations have been almost completed and about 90% of the data obtained so far has been reduced providing about 3000 galax

Guinevere Kauffmann

We use the semi-analytic models of galaxy formation developed by Kauffmann, White \& Guiderdoni to generate predictions for the observed properties of cluster and group galaxies at redshifts between 0 and 0.6. We examine four sets of cosmological initial conditions: low-density CDM models with and without cosmological constant, a flat CDM model and a mixed d

Dmitri Pogosyan, Alexei Starobinsky

The mixed cold-hot dark matter cosmological model (CHDM) with $Ω_{tot}=1$ and a falling power-law initial spectrum of Gaussian adiabatic perturbations ($n>1$) is tested using recent obserbational data. It is shown that its fit to the data becomes worse with the growth of $n-1$, and may be considered as unreasonable for $n>1.1$ for all possible values of the

Hyung Mok Lee

A star with main sequence mass greater than $25\sim 30\msun$ may collapse to a black hole of about 10 $\msun$ at the final stage of the evolution. About an order of 1\% of stellar mass is likely to be in form of such black holes in galaxies. We have examined the dynamics of two-component stellar systems composed of 0.7 $\msun$ main-sequence stars, representi

D. L. Stein, C. M. Newman

We study the nature and mechanisms of broken ergodicity (BE) in specific random walk models corresponding to diffusion on random potential surfaces, in both one and high dimension. Using both rigorous results and nonrigorous methods, we confirm several aspects of the standard BE picture and show that others apply in one dimension, but need to be modified in

M. R. Pennington, J. Portoles

The all--important consequence of Chiral Dynamics for $ππ$ scattering is the Adler zero, which forces $ππ$ amplitudes to grow asymptotically. The continuation of this subthreshold zero into the physical regions requires a $P$--wave resonance, to be identified with the $ρ$. It is a feature of $ππ$ scattering that convergent dispersive integrals for the $I=1$

S. Narison

Using the Laplace sum rule (LSR) approach, which is less affected by the contribution of the higher mass hadronic states than the Finite Energy Sum Rule (FESR), we test the reliability of the existing estimate of the $K^0$-$\overline {K}^0$ mixing parameter from the four-quark two-point correlator. We obtain, for the renormalization group invariant $B$-param

Joseph Polchinski

An infinite number of distinct $d=1$ matrix models reproduce the perturbation theory of $d=2$ string theory. Due to constraints of causality, however, we argue that none of the existing constructions gives a consistent nonperturbative definition of the $d=2$ string.

M. Sander, C. Beck, B. C. Schroeder, H. -B. Pyo

NN and Pi-N partial wave radial potentials have been generated using the latest SM94-VPI(NN) and FA93-VPI(Pi-N) phase shifts. The potentials are used to determine the deuteron properties and to compute the 3H and 3He binding energies. The e_1 mixing angles of SM94-VPI and NY93-Nijmegen differ significantly and inversion potentials yield a P_d of 6.37% and 5.

H. Nachbagauer, A. K. Rebhan, D. J. Schwarz

The exact solutions for linear cosmological perturbations which have been obtained for collisionless relativistic matter within thermal field theory are extended to a self-interacting case. The two-loop contributions of scalar $\lambda\phi^4$ theory to the thermal graviton self-energy are evaluated, which give the $O(\lambda)$ corrections in the perturbation

S. Meljanac, M. Milekovic, A. Perica

The deformed algebra $\cal{A(R)}$, depending upon a Yang-Baxter R- matrix, is considered. The conditions under which the algebra is associative are discussed for a general number of oscillators. Four types of solutions satisfying these conditions are constructed and two of them can be represented by generalized Jordan-Wigner transformations.Our analysis is i

Ch. Devchand, V. Ogievetsky

Reconsidering the harmonic space description of the self-dual Einstein equations, we streamline the proof that all self-dual pure gravitational fields allow a local description in terms of an unconstrained analytic prepotential in harmonic space. Our formulation yields a simple recipe for constructing self-dual metrics starting from any explicit choice of su

Atish Dabholkar

The one-loop contribution to the entropy of a black hole from field modes near the horizon is computed in string theory. It is modular invariant and ultraviolet finite. There is an infrared divergence that signifies an instability near the event horizon of the black hole. It is due to the exponential growth of the density of states and the associated Hagedor

Y. Meurice, G. Ordaz

We present a differential formulation of the recursion formula of the hierarchical model which provides a recursive method of calculation for the high-temperature expansion. We calculate the first 30 coefficients of the high temperature expansion of the magnetic susceptibility of the Ising hierarchical model with 12 significant digits. We study the departure

Percy Deift, Thomas Kriecherbauer, Stephanos Venakides

We begin with a description of recent numerical and analytical results that are closely related to the results of this paper.

Subir Ghosh

The Lagrangian model for anyon, presented in [6], is extended to include interactions with external, homogeneous electromagnetic field. Explicit electric and magnetic moment terms for the anyon are introduced in the Lagrangian. The 2+1-dimensional BMT equation as well as the correct value (2) of the gyromagnetic ratio is rederived, in the Hamiltonian framewo

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

We provide, with proofs, a complete description of the authors' construction of state-sum invariants announced in [CY], and its generalization to an arbitrary (artinian) semisimple tortile category. We also discuss the relationship of these invariants to generalizations of Broda's surgery invariants [Br1,Br2] using techniques developed in the case of

Michele Bourdeau

We study the topological-antitopological fusion equations for supersymmetric sigma models on Grassmannian manifolds G(k,N). We find a basis in which the metric becomes diagonal and the $tt^*$ equations become tractable. The solution for the metric of G(k,N) can then be described in terms of the metric for the $CP^{N-1}$ models. The IR expansion helps clarify

K. -H. Rehren, Ya. S. Stanev, I. T. Todorov

Pairs $å\subset \bb$ of local quantum field theories are studied, where $å$ is a chiral conformal \qft and $\bb$ is a local extension, either chiral or two-dimensional. The local correlation functions of fields from $\bb$ have an expansion with respect to $å$ into \cfb s, which are non-local in general. Two methods of computing characteristic invariant ratio

Shin'ichi Nojiri, Masako Kawamura, Akio Sugamoto

In two dimensional fluid, there are only two classes of swimming ways of micro-organisms, {\it i.e.}, ciliated and flagellated motions. Towards understanding of this fact, we analyze the swimming problem by using $w_{1+\infty}$ and/or $W_{1+\infty}$ algebras. In the study of the relationship between these two algebras, there appear the wave functions express

Alice Rogers

A theory of integration for anticommuting paths is described. This is combined with standard Itô calculus to give a geometric theory of Brownian paths on curved supermanifolds. (Invited lecture given at meeting on `Espaces de Lacets', Institut de Recherche Mathématique Advancée, Université Louis Pasteur, Strasbourg, June 1994.)

R. Chakrabarti, R. Jagannathan

Using the technique developed by Fronsdal and Galindo (Lett. Math. Phys. 27 (1993) 57) for studying the Hopf duality between the quantum algebras $Fun_{p,q}(GL(2))$ and $U_{p,q}(gl(2))$, the Hopf structure of $U_{p,q}(gl(1|1))$, dual to $Fun_{p,q}(GL(1|1))$, is derived and the corresponding universal ${\cal T}$-matrix of $Fun_{p,q}(GL(1|1))$, embodying the s

G. Sardanashvily

The multimomentum Hamiltonian formalism is applied to field systems represented by sections of composite manifolds $Y\to\Si\to X$ where sections of $\Si\to X$ are parameter fields, e.g., Higgs fields and gravitational fields. Their values play the role of coordinate parameters, besides the world coordinates.

S. Higuchi, C. Itoi, S. Nishigaki, N. Sakai

We summarize our recent results on the large N renormalization group (RG) approach to matrix models for discretized two-dimensional quantum gravity. We derive exact RG equations by solving the reparametrization identities, which reduce infinitely many induced interactions to a finite number of them. We find a nonlinear RG equation and an algorithm to obtain

Stephan Narison

We summarize the recent developments on the extraction of the dynamical properties of the heavy quarks from QCD spectral sum rules.

Paula J. Franzini

Proceedings of invited lecture at the Zuoz summer school on hadronic aspects of collider physics, August 23-31, 1994, Zuoz, Switzerland. Describes the PHI factory DAPHNE being built at Frascati, Italy, and the physics that can be done there, with emphasis on its potential for studying CP violation.

F. E. Close, G. J. Gounaris

$DAΦNE$ should be useful for testing the nature of the vector mesons directly produced in $e^-e^+$ annihilation, as well as the nature of the $C=+$ states produced in the radiative decays of these vector mesons. In the $DAΦNE$ energy range, these latter states may have spin up to two and any parity. Provided the background can be handled and the spin of the

H. Leutwyler

The aim of this introductory lecture is to review the arguments, according to which the symmetry properties of the strong interaction reveal themselves at low energies. I first discuss the symmetries of QCD, then sketch the method used to work out their implications and finally take up a few specific issues, where new experimental results are of particular i

H. Leutwyler

The paper concerns the effective field theory methods used to study the low energy structure of systems with a spontaneously broken symmetry. I first explain how the method works in the context of quantum chromodynamics and then discuss a few general aspects, related to the universality of effective theories. In particular, I compare some of the effective fi

Yue-Liang Wu, Lincoln Wolfenstein

Assuming CP violation arises solely through the Higgs potential, we develop the most general two-Higgs doublet model. There is no discrete symmetry that distinguishes the two Higgs bosons. It is assumed that an approximate global family symmetry sufficiently suppresses flavor-changing neutral scalar interactions. In addition to a CKM phase, neutral boson mix

Jihn E. Kim

In supergravity models, the quantum correction to the vacuum energy can be of order $M_I^4$, if the cutoff is of order the Planck mass $M^2_{P}$ and $Str\ {\cal M}^2\ne 0$. Therefore, the tree level cosmological constant must be nonzero (probably negative). Since the current practice of calculating soft parameters in supergravity models assumes the vanishing

J. L. Houser, J. M. Centrella, S. C. Smith

We present the first calculations of the gravitational radiation produced by nonaxisymmetric dynamical instability in a rapidly rotating compact star. The star deforms into a bar shape, shedding $\sim 4\%$ of its mass and $\sim 17\%$ of its angular momentum. The gravitational radiation is calculated in the quadrupole approximation. For a mass $M \sim 1.4$ M$

Nathalie Deruelle, Dalia S. Goldwirth

Using a long wavelength iteration scheme to solve Einstein's equations near the Big-Bang singularity of a universe driven by a massive scalar field, we find how big initial quasi-isotropic inhomogeneities can be before they can prevent inflation to set in.

Masaru Shibata, Misao Sasaki, Hideyuki Tagoshi, Takahiro Tanaka

Using the Teukolsky and Sasaki-Nakamura equations for the gravitational perturbation of the Kerr spacetime, we calculate the post-Newtonian expansion of the energy and angular momentum luminosities of gravitational waves from a test particle orbiting around a rotating black hole up through ${\rm P^{5/2}N}$ order beyond the quadrupole formula. We apply a meth

B. L. Hu

Concepts of quantum open systems and ideas of correlation dynamics in nonequilibrium statistical mechanics, as well as methods of closed-time-path effective action and influence functional in quantum field theory can be usefully applied for the analysis of quantum statistical processes in gravitation and cosmology. We raise a few conceptual questions and sug

Alexander Kumjian, Iain Raeburn, Dana P. Williams

If $X$ is a locally compact space which admits commuting free and proper actions of locally compact groups $G$ and $H$, then the Brauer groups $\Br_H(G/X)$ and $\Br_G(X/H)$ are naturally isomorphic.

Andrey V. Chubukov, David M. Frenkel

We propose a theory of two-magnon {\it resonant\/} Raman scattering from antiferromagnetic insulators, which contains information both on the magnetism and the carrier properties in the lighly doped phases. We argue that the conventional theory does not work in the resonant regime, in which the energy of the incident photon is close to the gap between the co

Yi-Peng Jing, Li-Zhi Fang

We show that a good fitting to the first two years of {\it COBE}-DMR observations of the two-point angular correlation function of CBR temperature is given by models with a non-zero infrared cutoff $k_{min}$ in the spectrum of the primordial density perturbations. If this cutoff comes from the finiteness of the universe, say, a topological T3 model, we find

Henry C. Ferguson, Stacy S. McGaugh

Low Surface-Brightness (LSB) galaxies are severely underrepresented in surveys used to define the local luminosity function (LF), but could it in principle be detected in deep surveys. To explore the possible contribution of such objects to faint galaxy counts, we construct catalogs of simulated non-evolving galaxies drawn from a multivariate distribution of

Toshiyuki Fukushige, Junichiro Makino

We give an estimate of the relative error in the angular measurement of observations for high redshift objects induced by gravitational scatterings (lensing). Gunn (1967) concluded that the gravitational scatterings by galaxies induce the relative error of a few percent in the observations for objects at $z=1$. This estimate has been considered as a fundamen

Toshiyuki Fukushige, Junichiro Makino, Toshikazu Ebisuzaki

The homogeneity of the cosmic microwave background radiation (CBR) is one of the most severe constraint for theories of the structure formation in the universe. We investigated the effect of the gravitational scattering (lensing) of galaxies, clusters of galaxies, and superclusters on the anisotropy of the CBR by numerical simulations. Although this effect w

M. Cappi, A. Comastri, S. Molendi, G. G. C. Palumbo

The BL Lac object 0716+714 is a powerful flat spectrum radio source detected by CGRO-EGRET at $γ$-ray energies. It has been observed for about 21000 s over two days by the X-ray telescope onboard the ROSAT satellite and strong flux and spectral variations have been detected. In the time scale of two days the source varied by a factor of $\sim 7$; during a su

A. Comastri, G. Setti, G. Zamorani, G. Hasinger

We report the results of a detailed analysis of the contribution of various classes of AGNs to the extragalactic X-ray background (XRB). The model is based on the unification schemes of AGNs and on their related X-ray spectral properties in the light of recent observational results. The integrated emission from AGNs, when folded with an appropriate cosmologi

E. Molinari, A. Buzzoni, G. Chincarini

We present deep CCD surface photometry in the Gunn g, r, i system and spectroscopy of the cD galaxy at the centre of the cluster A3284 at z = 0.15. The brightness profile of the galaxy has been tracked up to 40 arcsec (142 kpc) from the centre, and down to 26 mag/arcsec^2. The core and halo components in the galaxy have been singled out deriving geometrical

A. L. Gorodentsev

In this paper we consider orthogonal geometry of the free $\protect\ZZ$-module $K_0(\protect\PP_n)$ with respect to the non-symmetric unimodular bilinear form $$χ(E,F)=\sum (-1)^ν\dim\ext^ν(E,F). $$ We calculate the isometry group of this form and describe invariants of its natural action on $K_0(\protect\PP_n)$. Also we consider some general constructions w

Greg Anderson, Diego Castano

Fine-tuning criteria are frequently used to place upper limits on the masses of superpartners in supersymmetric extensions of the standard model. However, commonly used prescriptions for quantifying naturalness have some important shortcomings. Motivated by this, we propose new criteria for quantifying fine tuning that can be used to place upper limits on su

Yuval Grossman, Zoltan Ligeti

We calculate, in the framework of multi Higgs doublet models, the $CP$ violating transverse tau polarization, $P_\perp$, in inclusive semileptonic $B$ meson decays. We find that $P_\perp$ diverges at ${\cal O}(1/m_b^2)$ of the heavy quark expansion. We discuss the physical reasons for this divergence and show how to regularize it. We find large $1/m_b^2$ cor

Y. Y. Keum

We point out that polarization measurements such as the longitudinal fraction and the transverse left-right asymmetry in the Bauer-Stech-Wirbel (BSW) class III processes involving two final vector mesons, $B^- \ra ρ^- {D^*}^o$ taken as an example, are useful in determining the relative sign as well as the relative magnitudes of the coefficients $a_1$ and $a_

Stefano Forte

We review the theory of polarized structure functions measured in deep-inelastic lepton-nucleon scattering, focusing on the most recent developments. We concentrate on the structure function $g_1$, emphasizing the phenomenological problems related to the extraction of the proton and neutron $g_1(x,Q^2)$ from the data, and to the determination of its moments,

Hai-Yang Cheng, B. Tseng

Based on the factorization approach, we show that the CLEO data for the ratio $Γ(B\toψK^*)/Γ(B\to ψK)$ and the CDF measurement of the fraction of longitudinal polarization in $B\toψK^*$ can be accounted for by the heavy-flavor-symmetry approach for heavy-light form factors provided that the form factor $F_0$ behaves as a constant, while the $q^2$ dependence

C. J. Fewster, C. G. Wells

Interacting quantum fields on spacetimes containing regions of closed timelike curves (CTCs) are subject to a non-unitary evolution $X$. Recently, a prescription has been proposed, which restores unitarity of the evolution by modifying the inner product on the final Hilbert space. We give a rigorous description of this proposal and note an operational proble

T. Inagaki, T. Kouno, T. Muta

The phase structure of four-fermion theories is thoroughly investigated with varying temperature and chemical potential for arbitrary space-time dimensions $(2 \leq D < 4)$ by using the 1/N expansion method. It is shown that the chiral symmetry is restored in the theory under consideration for sufficiently high temperature and/or chemical potential. The crit

D. V. Juriev

The classical and quantum dynamics of noncanonically coupled os- cillators is investigated in its relation to Lie superalgebras. It is shown that the quantum dynamics admits a hidden (super)hamiltonian formulation and, hence, preserves the initial operator relations.

E. Dudas

This paper explores a recent idea of Nambu to generate hierarchies among Yukawa couplings in the context of effective supergravity and superstrings models. The Yukawa couplings are homogeneous functions of the moduli and a geometrical constraint between them with a crucial role in the Nambu mechanism is found in a class of models of no-scale type. The Yukawa

Y. Morita, Y. Hatsugai, M. Kohmoto

We study the correlations between eigenvalues of the large random matrices by a renormalization group approach. The results strongly support the universality of the correlations proposed by Brézin and Zee. Then we apply the results to the ground state of the 1D particles with long range interactions in a confinement potential. We obtain the exact ground stat

V. B. Belyaev, O. I. Kartavtsev, V. I. Kochkin, E. A. Kolganova

The method of hyperspherical &#34;surface&#34; functions has been applied to the calculation of eigenvalues and eigenfunctions of muonic molecular ions $^{3,4}\! H\! edμ$. Binding energies and nonradiative decay rates for the states of the total angular momentum $L=0,~1,~2$ have been obtained.

V. R. Manfredi, L. Salasnich

The transition from order to chaos in atomic nuclei has been studied analytically and numerically using a quadrupole--quadrupole residual interaction. This interaction leads to chaotic behaviour, but the critical energy $E_C\simeq 12.6$ MeV, corresponding to the onset of chaos, is higher than that of the experimental one.

D. Uglov

The representations of the degenerate affine Hecke algebra in which the analogues of the Dunkl operators are given by finite-difference operators are introduced. The non-selfadjoint lattice analogues of the spin Calogero-Sutherland hamiltonians are analysed by Bethe-Ansatz. The $ sl(m)$-Yangian representations arising from the finite-difference representatio

Atsushi Nakayashiki

We diagonalize the transfer matrix of the inhomogeneous vertex models of the 6-vertex type in the anti-ferroelectric regime intoducing new types of q-vertex operators. The special cases of those models were used to diagonalize the s-d exchange model\cite{W,A,FW1}. New vertex operators are constructed from the level one vertex operators by the fusion procedur

T. Horiguchi, K. Maeda, M. Sakmaoto

We solve the Wheeler-DeWitt equation for {\it four}-dimensional Einstein gravity as an expansion in powers of the Planck mass by means of a heat kernel regularization. Our results suggest that in the universe with a very small radius or with a very large curvature beyond a Planck scale expectation values of operators are reduced to calculations in a path int

S. Chaudhuri, S. -W. Chung, G. Hockney, J. Lykken

Phenomenologically viable string vacua may require incorporating Kac-Moody algebras at level $\geq 2$. We exploit the free fermionic formulation to construct N=(0,2) world-sheet supersymmetric string models with specific phenomenological input: N=1 spacetime supersymmetry, three generations of chiral fermions in gauge groups $SO(10)$ or $SU(5)$, adjoint Higg

Daniel I. Fivel

Completely entangled quantum states are shown to factorize into tensor products of entangled states whose dimensions are powers of prime numbers. The entangled states of each prime-power dimension transform among themselves under a finite Heisenberg group. We are thus led to examine processes in which factors are exchanged between entangled states and so con

D. Tadić, S. Žganec

There exist relativistic quark models (potential or MIT-bag) which satisfy the heavy quark symmetry (HQS) relations among meson decay constants and form factors. Covariant construction of the momentum eigenstates, developed here, can correct for spurious center-of-mass motion contributions.Proton form factor and M1 transitions in quarkonia are calculated. Ex

G. K. Leontaris, N. D. Tracas

We discuss low energy threshold effects and calculate the sparticle masses in the context of the Minimal Supersymmetric Standard Model. We pay particular attention to the top squark and the Higgs mass parameters, and calculate the top Yukawa corrections, taking into account the successive decoupling of each particle at its threshold. We discuss the phenomeno

AD Martin, WJ Stirling, RG Roberts

We extend the MRS(A) set of parton distributions, which provides an up-to-date description of the structure of the proton probed by hard interactions, into the region of $Q^2$ below $5\ {\rm GeV}^2$. After physically-motivated modifications, we obtain a smooth description of the data on the structure function $F_2(x,Q^2)$ all the way from $Q^2 = 10^{-1}$ to

P. A. Henning, Ch. Hoelbling

Within a field theoretical formalism suited to treat inhomogeneous hot quantum systems, we derive the two-particle correlation function for particles having a spectral width gamma in the region of their emission. We find, that this correlation function measures the radius R0 of the thermal source only in case gamma*R0 > 1.

G. Schierholz

One may argue that QCD solves the strong CP problem by itself, without having to introduce new symmetries and particles. To test this idea, a lattice simulation is performed. The problem is investigated in the CP$^3$ model first. It is found that the model has a first order phase transition in $θ$ from a confining phase at small $θ$ to a deconfining phase at

S. Carlip

The presence of a horizon breaks the gauge invariance of (2+1)-dimensional general relativity, leading to the appearance of new physical states at the horizon. I show that the entropy of the (2+1)-dimensional black hole can be obtained as the logarithm of the number of these microscopic states.

Jan Brinckmann

A new type of perturbation expansion in the mixing $V$ of localized orbitals with a conduction-electron band in the $U\to\infty$ Anderson model is presented. It is built on Feynman diagrams obeying standard rules. The local correlations of the unperturbed system (the atomic limit) are included exactly, no auxiliary particles are introduced. As a test, an inf

Shiwei Zhang, N. Kawashima, J. Carlson, J. E. Gubernatis

We introduce two novel quantum Monte Carlo methods and employ them to study the superfluid-insulator transition in a two-dimensional system of hard-core bosons. One of the methods is appropriate for zero temperature and is based upon Green&#39;s function Monte Carlo; the other is a finite-temperature world-line cluster algorithm. In each case we find that th

David P. DiVincenzo, John Smolin

We present numerical results which show how two-bit logic gates can be used in the design of a quantum computer. We show that the Toffoli gate, which is a universal gate for all classical reversible computation, can be implemented using a particular sequence of exactly five two-bit gates. An arbitrary three-bit unitary gate, which can be used to build up any

K. Ishikawa, N. Maeda, K. Tadaki

A deep connection between the Hall conductance in realistic situation and a topological invariant is pointed out based on von-Neumann lattice representation in which Landau level electrons have minimum spatial extensions. We show that the Hall conductance has no finite size correction in quantum Hall regime, but a coefficient of induced Chern-Simons term in

Andrew Gould

I propose a radical revision in the search strategy for Massive Compact Objects (Machos) toward the Galactic bulge: monitor the entire $\sim 300$ square deg of the bulge and tune the search primarily to microlensing events of bright $M_V\lsim 2$ stars. By employing a small second telescope to follow up the events detected with low dimensionless impact parame

Dan Kiselman, Mats Carlsson

We discuss the nature of non-LTE effects affecting abundance analysis of cool stars. The departures from LTE of importance for the B I lines in solar-type stars are described and some new results are presented. Boron abundances derived under the LTE assumption have significant systematic errors, especially for metal-poor stars. For beryllium, current results

Daniel I. Fivel

It is shown that the algebraic structure of finite Heisenberg groups associated with the tensor product of two Hilbert spaces leads to a simple demonstration valid in all Hilbert space dimensions of the impossibility of non-contextual hidden variables.

Daniel I. Fivel

(Presented at conference on Fundamental Problems in Physics - UMBC - June 1994) It is shown that among the orthogonal sets of EPR (completely entangled) states there is a unique basis (up to equivalence) that is a also a perfectly resolved set of coherent states with respect to a pair of complementary observables. This basis defines a lattice phase space in

Hideo Suganuma, Shoichi Sasaki, Hiroshi Toki

We study nonperturbative features of QCD using the dual Ginzburg-Landau theory. The color confinement is realized through the dual Higgs mechanism, which is brought by QCD-monopole condensation. We investigate the infrared screening effect on the color confinement due to the light-quark pair creation. By solving the Schwinger-Dyson equation, we find that the

Shoichi Sasaki, Hideo Suganuma, Hiroshi Toki

We study the effect of QCD-monopole condensation on the dynamical chiral-symmetry breaking by using the dual Ginzburg-Landau theory of QCD. We formulate the Schwinger-Dyson equation and solve it numerically. The large enhancement is found for the chiral-symmetry breaking due to QCD-monopole condensation, which suggests the close relation between the color co

J. Rosiek, A. Sopczak

New mass regions unexcluded by direct searches are revealed by an analysis of experimental results from LEP1 using full 1-loop diagrammatic calculations of radiative corrections in the MSSM. Simulations of experimental signal efficiencies and background rejection factors, and full 1-loop calculations are combined to study the sensitivity for neutral Higgs bo

A. P. Kobushkin, A. I. Syamtomov

Experimental observables of the elastic eD-scattering in the region of intermediate energies are discussed. We offer the analysis of the available experimental data, which reproduces the results of the calculations with popular $NN$-potentials at low energies ($Q^2\ll 1(GeV/c)^2$), but, at the same time, provides the right asymptotic behavior of the deuteron

B. W. Harris, J. Smith

We present new one loop calculations that confirm the theorems of Joglekar and Lee on the renormalization of composite operators. We do this by considering physical matrix elements with the operators inserted at non-zero momentum. The resulting IR singularities are regulated dimensionally. We show that the physical matrix element of the BRST exact gauge vari

Alan Chodos, Alan Kostelecky, IUHET 280

Recently, a type of null experiment for spacelike neutrinos has been proposed. We examine in detail a class of null tests involving nuclear beta decay or capture in atoms and ions. The most promising candidate systems are identified.

Dean Lee

The light quark-antiquark scattering Green&#39;s function is considered near a meson resonance peak. The Bethe-Salpeter equation is used to write formal expressions for the resonance width/mass ratio. Arguments are made concerning to what extent this ratio can be calculated perturbatively, and an upper bound is placed on the growth of this ratio as a functio

Xiaoyuan Li, Yi Liao

The applicability of the background field method in spontaneously broken gauge theories is examined with new features emphasized. An explicit one loop analysis in the electroweak theory shows that the method can be consistently implemented in the on-shell renormalization scheme, and that the choice of the background gauge cannot be arbitrary and must be fixe

Chuck Yeung, Madan Rao, Rashmi Desai

We obtain bounds on the decay exponent lambda of the autocorrelation function in phase ordering dynamics. For non-conserved order parameter, we recover the Fisher and Huse inequality, lambda > = d/2. If the order parameter is conserved we also find lambda >= d/2 if the initial time t1 = 0. However, for t1 in the scaling regime, we obtain lambda >= d/2 + 2 fo

Peter Schneider

The reconstruction of the density profile in clusters of galaxies from the distortion of the images of faint background galaxies is reconsidered. The inversion formula of Kaiser \& Squires is known to provide a quantitative way to perform this reconstruction; however, the practical application of this formula faces two problems of principle (besides problems

E. V. Shuryak, J. J. M. Verbaarschot

Screening of the topological charge due to he fermion-induced interactions is an important phenomenon, closely related with the resolution of the strong CP and U(1) problems. We study the mechanism of such screening in a &#39;correlated instanton vacuum&#39;, as opposed to the &#39;random&#39; one. Both scalar and pseudoscalar gluonic correlators are analyze

E. Gaztanaga, C. M. Baugh

We present a comparison of the predictions of perturbation theory for the hierarchical J-order correlation amplitudes $S_J=\xibar_J/\xibar_2^{J-1}$, $J=3-10$, with the results of large numerical simulations of gravitational clustering. We consider two different initial power spectra of density fluctuations, one being flatter than the other. The clustering am

Scott C. Smith, Joan M. Centrella, Sean P. Clancy

We have developed a 3-D Eulerian hydrodynamics code to model sources of gravitational radiation. The code is written in cylindrical coordinates $(\varpi,z,φ)$ and has moving grids in the $\varpi$ and $z$-directions. We use Newtonian gravity and calculate the gravitational radiation in the quadrupole approximation. This code has been tested on a variety of pr

Denis V. Juriev

Classical dynamical equations describing a certain version of the nonHamiltonian interaction of two rotators (Euler tops with completely degenerate inertia tensors) are considered. The simplest case is integrated. It is shown that the dynamics is almost periodic with periods depending on the initial data.

A. Nersessian

We construct the odd symplectic structure and the equivariant even (pre)symplectic one from it on the space of differential forms on the Riemann manifold. The Poincare -- Cartan like invariants of the second structure define the equivariant generalizations of the Euler classes on the surfaces.

Leon Balents, Steven H. Simon

Two types of commensurability effects are possible in a large Josephson junction patterned with columnar defects. The first occurs for a periodic array of pins when the mean fluxon spacing (tuned by the magnitude of the applied in--plane magnetic field) is a rational fraction of the defect spacing. We show that this effect leads, under fairly general conditi

Z. Bern, L. Dixon, D. A. Kosower

We present the one-loop QCD amplitudes for two external massless quarks and three external gluons ($\bar{q}qggg$). This completes the set of one-loop amplitudes needed for the next-to-leading-order corrections to three-jet production at hadron colliders. We also discuss how to use group theory and supersymmetry to minimize the amount of calculation required

Peter A. Clarkson, Elizabeth L. Mansfield

In this paper we study symmetry reductions and exact solutions of the shallow water wave (SWW) equation $$u_{xxxt} + αu_x u_{xt} + βu_t u_{xx} - u_{xt} - u_{xx} = 0,\eqno(1)$$ where $α$ and $β$ are arbitrary, nonzero, constants, which is derivable using the so-called Boussinesq approximation. Two special cases of this equation, or the equivalent nonlocal equ

Martin Treiber, Lorenz Kramer

The common description of the electrical behavior of a nematic liquid crystal as an anisotropic dielectric medium with (weak) ohmic conductivity is extended to an electrodiffusion model with two active ionic species. Under appropriate, but rather general conditions the additional effects can lead to a distinctive change of the threshold behavior of the elect