arXiv papers from March 1995

L. Roszkowski

I review some aspects of supersymmetric grand unification and emphasize a recent development in the area of gauge coupling unification.

A. LeClair, G. Mussardo, H. Saleur, S. Skorik

We study the ground state energy of integrable $1+1$ quantum field theories with boundaries (the genuine Casimir effect). In the scalar case, this is done by introducing a new, ``R-channel TBA'', where the boundary is represented by a boundary state, and the thermodynamics involves evaluating scalar products of boundary states with all the states of the theo

Daryl Scora, Nathan Isgur

We present the predictions of ISGW2, an update of the ISGW quark model for semileptonic meson decays. The updated model incorporates a number of features which should make it more reliable, including the constraints imposed by Heavy Quark Symmetry, hyperfine distortions of wavefunctions, and form factors with more realistic high recoil behaviors.

Doochul Kim

A perturbative method is developed to calculate the finite size corrections of the low lying energies of the asymmetric XXZ hamiltonian near the stochastic line. The crossover from isotropic to anisotropic, Kardar-Parisi-Zhang (KPZ) scaling of the mass gaps is determined in terms of universal crossover scaling functions. At the stochastic line, the asymmetri

Troy A. Schilling

A key aspect of a recent proposal for a {\em generalized loop representation} of quantum Yang-Mills theory and gravity is considered. Such a representation of the quantum theory has been expected to arise via consideration of a particular algebra of observables -- given by the traces of the holonomies of {\em generalized loops}. We notice, however, a technic

Alon Drory

This paper presents a general approach to linear stochastic processes driven by various random noises. Mathematically, such processes are described by linear stochastic differential equations of arbitrary order (the simplest non-trivial example is $\ddot x = R(t)$, where $R(t)$ is not a Gaussian white noise). The stochastic process is discretized into $n$ ti

Adam F. Falk

Theoretical aspects of rare $B$ decays are reviewed. The focus is on the relation between short-distance interactions and physical observables. It is argued that there remain significant uncertainties in the theoretical treatment of certain important quantities. (Talk presented at the International Symposium on Vector Boson Interactions, University of Califo

Orlando Alvarez, Chien-Hao Liu

It has been suggested that a possible classical remnant of the phenomenon of target-space duality (T-duality) would be the equivalence of the classical string Hamiltonian systems. Given a simple compact Lie group $G$ with a bi-invariant metric and a generating function $\Gamma$ suggested in the physics literature, we follow the above line of thought and work

J. S. Bagla, T. Padmanabhan

In an expanding universe, velocity field and gravitational force field are proportional to each other in the linear regime. Neither of these quantities evolve in time and these can be scaled suitably so that the constant of proportionality is unity and velocity and force field are equal. The Zeldovich approximation extends this feature beyond the linear regi

J. Machta, R. Greenlaw

In this paper we examine a number of models that generate random fractals. The models are studied using the tools of computational complexity theory from the perspective of parallel computation. Diffusion limited aggregation and several widely used algorithms for equilibrating the Ising model are shown to be highly sequential; it is unlikely they can be simu

Tim R. Morris

For all Poincar\'e invariant Lagrangians of the form ${\cal L}\equiv f(F_{\mu\nu})$, in three Euclidean dimensions, where $f$ is any invariant function of a non-compact $U(1)$ field strength $F_{\mu\nu}$, we find that the only continuum limit (described by just such a gauge field) is that of free field theory: First we approximate a gauge invariant version o

D. Kazhdan, Y. Soibelman

In this paper we define a quantum version of the ``fusion'' tensor product of two representations of an affine Kac-Moody algebra.It is replaced by what we call fusion action of the category of finite-dimensional representations of quantum affine algebra on its highest weight representations. We construct a quantum version of the associativity constraint. We

Afsar Abbas

It is shown, for the first time , that surprisingly the electric charge loses all physical meaning above the electro-weak phase transition temperature. Implications of this discovery in the context of the early universe within the framework of various unified models are discussed.

B. W. Harris, J. Smith

We have completed the next-to-leading order perturbative QCD corrections to the virtual-photon exclusive differential cross sections for heavy quark production in deep-inelastic electron-proton scattering, i.e. $e + P \rightarrow Q + \overline{Q} + X$. Using these results, we have computed distributions which are sensitive to correlations among the heavy qua

J. Sirkka, I. Vilja

We study the subcritical bubble formation near the phase space domain wall. We take into account that the phase of the scalar field can vary using complex U(1) symmetric field and a phenomenological potential with cubic term responsible to symmetry breaking. We show that the presence of the domain wall induces subcritical bubbles so that their formation rate

A. J. Bray, C. L. Emmott

The coarsening dynamics of the Cahn-Hilliard equation with order-parameter dependent mobility, $\lambda(\phi) \propto (1-\phi^2)^\alpha$, is addressed at zero temperature in the Lifshitz-Slyozov limit where the minority phase occupies a vanishingly small volume fraction. Despite the absence of bulk diffusion for $\alpha>0$, the mean domain size is found to g

Joachim Ankerhold, Hermann Grabert, Gert-Ludwig Ingold

We study the real time dynamics of a quantum system with potential barrier coupled to a heat-bath environment. Employing the path integral approach an evolution equation for the time dependent density matrix is derived. The time evolution is evaluated explicitly near the barrier top in the temperature region where quantum effects become important. It is show

V. D. Ivashchuk, V. N. Melnikov

A cosmological model describing the evolution of n Ricci-flat spaces (n>1) in the presence of 1-component perfect-fluid and minimally coupled scalar field is considered. When the pressures in all spaces are proportional to the density, the Einstein and Wheeler-DeWitt equations are integrated for a large variety of parameters. Classical and quantum wormhole s

B. M. Pimentel, J. L. Tomazelli

In this letter we argue that there is no ambiguity between the Pauli-Villars and other methods of regularization in (2+1)-dimensional quantum electrodynamics with respect to dynamical mass generation, provided we properly choose the couplings for the regulators.

K. Rummukainen, Steven Gottlieb

Many low energy hadrons, such as the rho, can be observed as resonances in scattering experiments. A proposal by L\"uscher enables one to determine infinite volume elastic scattering phases from the two-particle energy spectrum measured from finite periodic lattices. In this work, we generalize the formalism to the case where the total momentum of the partic

S. Franz, G. Parisi

In this paper we develop a method introduced by one of us to study metastable states in spin glasses. We consider a `potential function' defined as the free energy of a system at a given temperature $T$ constrained to have a fixed overlap with a reference configuration of equilibrium at temperature $T'$. We apply the method to the spherical p-spin glass and

Masato JIMBO, Tadashi KON, Hidekazu TANAKA, Toshiaki KANEKO

We introduce a new method to treat Majorana fermions on the GRACE system, which has already been developed for the computation of the matrix elements for the processes of the standard model. In the standard model, we already have included such particles as Dirac fermions, gauge bosons and scalar bosons in the system. On the other hand, there are four Majoran

D. Arnaudon, C. Chryssomalakos, L. Frappat

We examine the two parameter deformed superalgebra $U_{qs}(sl(1|2))$ and use the results in the construction of quantum chain Hamiltonians. This study is done both in the framework of the Serre presentation and in the $R$-matrix scheme of Faddeev, Reshetikhin and Takhtajan (FRT). We show that there exists an infinite number of Casimir operators, indexed by i

Silvia Zane, Roberto Turolla, Luca Zampieri, Monica Colpi

The issue of the observability of Old Isolated Neutron Stars (ONSs) accreting from the interstellar gas, is reconsidered using the spectra presented in Zampieri {\it et al.\/} (1995). In particular, we focus our attention on the overall soft X--ray emission of ONSs, which may provide a substantial contribution to the X--ray background in the 0.5--2 keV band.

X de Hemptinne

The dynamics of irreversible relaxation of non-equilibrium macroscopic systems is discussed. Arguments are developed showing that the general process is supported by two independent successive mechanisms. One is mixing and it follows pure conservative dynamics. It does not lead to thermodynamic equilibrium. The second step involves dissipation to the outside

Enzo Marinari, Maria Luigia Paciello, Bruno Taglienti

A review article on string tension concept and their relevance as non-perturbative quantity on the study of quark confinement in lattice gauge theories. A detailed description of a variety of methods to measure the string tension on the lattice and an indication of the most promising developments is proposed.

Z. K. Silagadze

The existence of the mirror world, with the same microphysics as our own one but with opposite P-asymmetry, not only restores an exact equivalence between left and right but also naturally explains, via a see-saw like mechanism, why the neutrino is ultralight.

CJ Isham, N Linden

We treat continuous histories within the histories approach to generalised quantum mechanics. The essential tool is the `history group': the analogue, within the generalised history scheme, of the canonical group of single-time quantum mechanics.

R. Monasson

The metastable states of a glass are counted by adding a weak pinning field which explicitly breaks the ergodicity. Their entropy, that is the logarithm of their number, is extensive in a range of temperatures $T_G < T < T_C$ only, where $T_G$ and $T_C$ correspond to the ideal calorimetric and kinetic glass transition temperatures respectively. An explicit s

P. Forgács, P. A. Horváthy, Z. Horváth, L. Palla

Some of the motivations for as well as the main points of the quantization of the Nappi Witten string in the light cone gauge are reviewed.

Michel Dubois-Violette, Peter W. Michor

We define and study the theory of derivation-based connections on a recently introduced class of bimodules over an algebra which reduces to the category of modules whenever the algebra is commutative. This theory contains, in particular, a noncommutative generalization of linear connections. We also discuss the different noncommutative versions of differenti

Alexei Iantchenko, Elliott H. Lieb, Heinz Siedentop

The strong Scott conjecture about the electron density at a distance 1/Z from an atomic nucleus of charge $Z$ and its generalization for molecules are proved. The density, suitably scaled, converges to an explicit limiting density as $Z \to \infty$. Both a weak convergence and a pointwise convergence on spheres holds.

Graciela Gelmini, Bruce Ritzi

Here we point out that the four-nucleon terms incorporate into lowest order non-linear chiral effective Lagrangians the same description of bulk nuclear matter contained in the Walecka model, that is generally considered satisfactory. We find this point worth noticing because, while the Walecka model is an entirely phenomenological renormalizable model, non-

D. Troltenier, C. Bahri, J. P. Draayer

An extended version of the pseudo-SU(3) model which includes both spin and proton-neutron degrees of freedom is used to study the influence of the pairing interaction on K-band mixing, B(E2) values and quadrupole moments. Using the asymmetric rotor model as a backdrop, specific consequences of a many-particle shell-model based description of these collective

N. J. Hitchin, N. S. Manton, M. K. Murray

We discuss $SU(2)$ Bogomolny monopoles of arbitrary charge $k$ invariant under various symmetry groups. The analysis is largely in terms of the spectral curves, the rational maps, and the Nahm equations associated with monopoles. We consider monopoles invariant under inversion in a plane, monopoles with cyclic symmetry, and monopoles having the symmetry of a

R. B. Palmer, J. C. Gallardo, R. C. Fernow, Y. Torun

Muon production requirements for a muon collider are presented. Production of muons from pion decay is studied. Lithium lenses and solenoids are considered for focussing pions from a target, and for matching the pions into a decay channel. Pion decay channels of alternating quadrupoles and long solenoids are compared. Monte Carlo simulations are presented fo

H. Baer, A. Bartl, C. H. Chen, H. Eberl

We summarize the current status and future prospects for low energy (weak scale) supersymmetry. In particular, we evaluate the capabilities of various $e^+e^-$, $p\bar p$ and $pp$ colliders to discover evidence for supersymmetric particles. Furthermore, assuming supersymmetry is discovered, we discuss capabilities of future facilities to dis-entangle the ant

A. A. Balinsky, Yu. M. Burman

The paper is devoted to the Poisson brackets compatible with multiplication in associative algebras. These brackets are shown to be quadratic and their relations with the classical Yang--Baxter equation are revealed. The paper also contains a description of Poisson Lie structures on Lie groups whose Lie algebras are adjacent to an associative structure.

Richard C. Fernow, Juan C. Gallardo

Transverse ionization cooling of muons is modeled as a Brownian motion of the muon beam as it traverses a Li or Be rod. A Langevin like equation is written for the free particle case (no external transverse magnetic field) and for the case of a harmonically bound beam in the presence of a focusing magnetic field. We demonstrate that the well known muon cooli

Jisuke Kubo, 11 pages, KANAZAWA-94-01

An evidence for nontriviality of asymptotically non-free (ANF) Yang-Mills theories is found on the basis of optimized perturbation theory. It is argued that these theories with matter couplings can be made nontrivial by means of the reduction of couplings, leading to the idea of dynamical unification of couplings (DUC) The second-order reduction of couplings

R. B. Palmer, J. C. Gallardo, R. C. Fernow, H. Kirk

We discuss the various beam dynamics problems in muon collider systems, starting from the proton accelerator needed to generate the muon beams and proceeding through the muon storage ring.

Alejandro Adem

In this paper we use families of finite subgroups to study Grothendieck rings associated to certain discrete groups, such as the arithmetic ones.

Aviezri S. Fraenkel

Aim: Present a systematic development of part of the theory of combinatorial games from the ground up. Approach: Computational complexity. Combinatorial games are completely determined; the questions of interest are efficiencies of strategies. Methodology: Divide and conquer. Ascend from Nim to chess in small strides at a gradient that's not too steep. Prese

Todd R. Hunter, Leonardo Testi, Greg B. Taylor, Marcello Felli

We present molecular line, H2O maser, radio continuum and near infrared maps of the bipolar outflow source AFGL5142. The high resolution of our molecular CO observations enables us to define the morphology of the large-scale bipolar outflow into a two lobe structure extending for 2&#39; on each side of the center. In the perpendicular direction, we find cons

James V. Steele, Ajay Subramanian, Ismail Zahed

The general correlations between massless fermions are calculated in the Schwinger model at arbitrary temperature. The zero temperature calculations on the plane are reviewed and clarified. Then the finite temperature fermionic Green's function is computed and the results on the torus are compared to those on the plane. It is concluded that a simpler way to

Kyungsik Kang, Sin Kyu Kang

We critically reexamine the precision tests of the standard model by coupling the current world average value of $M_W$ with the recent LEP electroweak data with the aid of a modified ZFITTER program to include the dominant two-loop and QCD-EW mixed terms. The results show a clear evidence of nonvanishing electroweak radiative corrections. The recent CDF $m_t

Stefan Lenz, Bernd Schreiber

The Poincare algebra of classical electrodynamics in one spatial dimension is studied using light-cone coordinates and ordinary Minkowski coordinates. We show that it is possible to quantize the theory by a canonical quantization procedure in a Poincare invariant manner on the light-cone. We also show that this is not possible when using ordinary coordinates

Armen Edigarian

In the paper we generalize the notion of problem (P) introduced by Poletsky. We introduce the notion of (P_m) extremals. For example, geodesics are (P_1) extremals. Using obtained results we present a description of (P_m) extremals in arbitrary complex ellipsoids. It is a generalization of the result obtained by Jarnicki-Pflug-Zeinstra. We also have a proof

M. G. Olsson, S. Veseli, K. Williams

We present a systematic algebraic and numerical investigation of the instantaneous Bethe-Salpeter equation. Emphasis is placed on confining interaction kernels of the Lorentz scalar, time component vector, and full vector types. We explore stability of the solutions and Regge behavior for each of these interactions, and conclude that only time component vect

E. Beggs, J. Gould, S. Majid

We compute the quantum double, braiding and other canonical Hopf algebra constructions for the bicrossproduct Hopf algebra $H$ associated to the factorization of a finite group into two subgroups. The representations of the quantum double are described by a notion of bicrossed bimodules, generalising the cross modules of Whitehead. We also show that self-dua

Gary T. Horowitz, Robert Myers

We point out that spacetime singularities play a useful role in gravitational theories by eliminating unphysical solutions. In particular, we argue that any modification of general relativity which is completely nonsingular cannot have a stable ground state. This argument applies both to classical extensions of general relativity, and to candidate quantum th

Leovigildo Alonso, Ana Jeremías, Joseph Lipman

We prove a sheaf-theoretic derived-category generalization of Greenlees-May duality (a far-reaching generalization of Grothendieck's local duality theorem): for a quasi-compact separated scheme X and a "proregular" subscheme Z---for example, any separated noetherian scheme and any closed subscheme---there is a sort of sheafified adjointness between local coh

E. V. Podivilov, D. A. Shapiro, M. G. Stepanov

The profile of a Bennett hole induced by laser field in ionic distribution in collisional plasma is calculated. Influence of Chandrasekhar's dependence of coefficients of velocity space transport on the profile is included into the calculation for the first time. It is found that the hole narrows down as the field detuning frequency increases. Physical cause

Sergey Merkulov, Henrik Pedersen

It is shown that moduli spaces of complete families of compact complex hypersurfaces in complex manifolds often come equipped canonically with projective structures satisfying some natural integrability conditions.

Claes Uggla, Robert T. Jantzen, Kjell Rosquist

A framework is introduced which explains the existence and similarities of most exact solutions of the Einstein equations with a wide range of sources for the class of hypersurface-homogeneous spacetimes which admit a Hamiltonian formulation. This class includes the spatially homogeneous cosmological models and the astrophysically interesting static spherica

K. Glazebrook, R. Ellis, M. Colless, T. Broadhurst

Using the multislit LDSS-2 spectrograph on the {\it William Herschel Telescope} we have completed a redshift survey in the magnitude range $22.5<B< 24$ which has produced 73 redshifts representing a 73\% complete sample uniformly-selected from four deep fields at high Galactic latitude. The survey extends out to $z>1$ and includes the highest redshift galaxy

C. Quitmann, B. Beschoten, R. J. Kelley, G. Guentherodt

Substitution of rare-earth ions for Ca in Bi2Sr2CaCu2O8+y is known to cause a metal-insulator transition. Using resonant photoemission we study how this chemical substitution affects the electronic structure of the material. For the partial Cu-density of states at E_F and in the region of the valence band we observe no significant difference between a pure s

Clement Sire, Satya N. Majumdar

We study the nonequilibrium dynamics of the $q$-state Potts model following a quench from the high temperature disordered phase to zero temperature. The time dependent two-point correlation functions of the order parameter field satisfy dynamic scaling with a length scale $L(t)\sim t^{1/2}$. In particular, the autocorrelation function decays as $L(t)^{-\lamb

Silvia Mollerach, Alejandro Gangui, Francesco Lucchin, Sabino Matarrese

We compute the contribution to the three--point temperature correlation function of the Cosmic Microwave Background coming from the non--linear evolution of Gaussian initial perturbations, as described by the Rees--Sciama (or integrated Sachs--Wolfe) effect. By expressing the collapsed three--point function in terms of multipole amplitudes, we are able to ca

O. Benhar, S. Liuti

We discuss how the virtuality of the struck particle may affect the final state interactions in electron-nucleus scattering. The extent to which short range correlations inhibit rescattering taking place within the range of the repulsive core of the NN interaction is quantitatively analyzed. The possible modifications of the nucleon-nucleon scattering amplit

Clement Sire

In this letter, I solve a model for the dynamics of vortices in a decaying two-dimensional turbulent fluid. The model describes their effective diffusion, and the merging of pairs of vortices of same vorticity sign, when they get too close. The merging process is characterized by the conservation of energy and of the quantity $Nr^n$, where $r$ is the mean vo

Sanjoy K. Sarker

The normal-state resistivity of the cuprate superconductors is metallic in the $ab$ plane but is characteristic of an insulator along the $c$ direction, leading to the possibility of the remarkable phenomenon of confinement. By continuity, such a behavior is not expected to occur in a Fermi liquid. We consider the anisotropic $t$-$J$ model with the c-axis pa

Boris Chibisov Ariel R. Zhitnitsky

We discuss some QCD constraints on light-cone $\pi$ meson wave function $\psi(\k, x)$ . The analysis is based on such general methods as dispersion relations, duality and PCAC. We calculate the asymptotical behavior of the wave function ($wf$) at the end-point region ($x\to 1$ and $\k\to\infty$) by analysing the corresponding large $n-$th moments in transver

S. Suresh Rao, Somendra M. Bhattacharjee

We explicitly show the connection between the protein folding problem and spin glass transition. This is then used to identify appropriate quantities that are required to describe the transition. A possible way of observing the spin glass transition is proposed.

Markus Finkemeier, Erwin Mirkes

Predictions for semi-leptonic decay rates of the tau lepton into two and three meson final states with one or two kaons are derived, including a discussion of K_S pi- K_S, K_L pi- K_L and K_S pi- K_L. The hadronic matrix elements are expressed in terms of form factors, which can be predicted by chiral Lagrangians supplemented by informations about all possib

Youngman Kim, Hyun Kyu Lee, Mannque Rho

We calculate the finite-temperature corrections in the dilated chiral quark model using the effective potential formalism. Assuming that the dilaton limit is applicable at some short length scale, we interpret the results to represent the behavior of hadrons in dense {\it and} hot matter. We obtain the scaling law, $\frac{f_{\pi}(T)}{f_{\pi}} = \frac{m_Q (T)

V. Anisovich, D. Melikhov, V. Nikonov

We consider the pion structure in the region of low and moderately high momentum transfers: at low $Q^2$, the pion is treated as a composite system of constituent quarks; at moderately high momentum transfers, $Q^2=10\div25\;GeV^2$, the pion \ff is calculated within perturbative QCD taking into account one--gluon hard exchange. Using the data on pion \ff at

J. L. Goity, Marc Sher

The most general supersymmetric model contains baryon number violating terms of the form $\lm_{ijk}\ \ov{D}_i\ \ov{D}_j\ \ov{U}_k$ in the superpotential. We reconsider the bounds on these couplings, assuming that lepton number conservation ensures proton stability. These operators can mediate $n-\ov{n}$ oscillations and double nucleon decay. We show that neu

M. Shmatikov

Width of molecular-type $Q\bar{Q}q\bar{q}$ hadronic states is discussed. It depends on the quantum numbers of the state and on the details of the long-range mechanism ensuring the bindedness of a molecule. Specific cases when the width is large are considered in detail.

M. Goeckeler, R. Horsley, P. E. L. Rakow, G. Schierholz

We investigate effective Yukawa couplings of mesons to the elementary fermions in noncompact lattice QED. The couplings are extracted from suitable fermion-antifermion-meson three-point functions calculated by Monte Carlo simulations with dynamical staggered fermions. The scaling behaviour is compatible with expectations from perturbation theory, thus indica

B. Linet

We consider a point charge fixed in the Rindler coordinates which describe a uniformly accelerated frame. We determine an integral expression of the induced charge density due to the vacuum polarization at the first order in the fine structure constant. In the case where the acceleration is weak, we give explicitly the induced electrostatic potential.

Laszlo Feher, Ian Marshall

The $p\times p$ matrix version of the $r$-KdV hierarchy has been recently treated as the reduced system arising in a Drinfeld-Sokolov type Hamiltonian symmetry reduction applied to a Poisson submanifold in the dual of the Lie algebra $\widehat{gl}_{pr}\otimes {\Complex}[\lambda, \lambda^{-1}]$. Here a series of extensions of this matrix Gelfand-Dickey system

J. Marklof

Asymptotic laws for mean multiplicities of lengths of closed geodesics in arithmetic hyperbolic three-orbifolds are derived. The sharpest results are obtained for non-compact orbifolds associated with the Bianchi groups SL(2,o) and some congruence subgroups. Similar results hold for cocompact arithmetic quaternion groups, if a conjecture on the number of gap

M. Yu. Kalmykov, P. I. Pronin

The ambiguity in the calculations of one-loop counterterms by the background field method in nonrenormalizable theories of gravity is discussed. Some examples of such ambiguous calculations are given. The non-equivalence of the first and second order formalism in the quantum gravity is shown.

Edouard Gorbar, Stefan Mashkevich, Sergei Sharapov

We consider particles in three-dimensional space, which have a certain probability to find themselves in a thin layer (``plane''), where they are assumed to be well described by a planar Hamiltonian and are subject to Aharonov-Bohm-type interaction. We demonstrate that their planar motion is then anyonlike, with the ``effective statistical parameter'' propor

J. A. Nieminen

Surface reconstructions of Au film on Pd(110) substrate are studied using a local Einstein approximation to quasiharmonic theory with the Sutton-Chen interatomic potential. Temperature dependent surface free energies for different coverages and surface structures are calculated. Experimentally observed transformations from $(1\times1)$ to $(1 \times 2)$ and

Subir Sachdev, Antoine Georges

We study the quantum transition from a strongly correlated metal, with heavy fermionic quasiparticles, to a metal with commensurate charge or spin density wave order. To this end, we introduce and numerically analyze a large dimensionality model of Ising spins in a transverse field, coupled to two species of fermions; the analysis borrows heavily from recent

A. A. Penin, A. A. Pivovarov

We consider a two-point correlator in massless $\phi^3$ model within the ladder approximation . The spectral density of the correlator is known explicitly and does not contain any resonances. Meanwhile making use of the standard sum rules technique with a simple "resonance + continuum" model of the spectrum allows to predict parameters of the "resonance" ver

V. A. Soroka

Some applications of the odd Poisson bracket to the description of the classical and quantum dynamics are represented.

R. Hilfer, N. B. Wilding

Critical finite-size scaling functions for the order parameter distribution of the two and three dimensional Ising model are investigated. Within a recently introduced classification theory of phase transitions, the universal part of the critical finite-size scaling functions has been derived by employing a scaling limit that differs from the traditional fin

G. K. Savvidy, K. G. Savvidy, F. J. Wegner

We are able to perform the duality transformation of the spin system which was found before as a lattice realization of the string with linear action. In four and higher dimensions this spin system can be described in terms of a two-plaquette gauge Hamiltonian. The duality transformation is constructed in geometrical and algebraic language. The dual Hamilton

P. Crehan, T. G. Ho

Phase-space realisations of an infinite parameter family of quantum deformations of the boson algebra in which the $q$-- and the $qp$--deformed algebras arise as special cases are studied. Quantum and classical models for the corresponding deformed oscillators are provided. The deformation parameters are identified with coefficients of non-linear terms in th

C. Hamzaoui, M. E. Pospelov

We show that the existence of a possible fourth heavy generation of quarks gives rise to a significant enhancement to the neutron electric dipole moment in comparison with the Standard Model prediction. The smaller degree of suppression in this case is linked to the presence of the operators of dimension $\leq$ 6 which enter into the effective Lagrangian wit

Metin Gurses, Emre Sermutlu

Collision of plane waves in dilaton gravity theories and low energy limit of string theory is considered. The formulation of the the problem and some exact solutions are presented.

Eva Silverstein, Edward Witten

It is argued that many linear (0,2) models flow in the infrared to conformally invariant solutions of string theory. The strategy in the argument is to show that the effective space-time superpotential must vanish because there is no place where it can have a pole. This conclusion comes from either of two different analyses, in which the Kahler class or the

L. Guzzo, K. B. Fisher, M. S. Strauss, R. Giovanelli

We present some new results from an ongoing investigation of the anisotropy of the two--point correlation function for optically selected galaxies. We have estimated xi(r_p,pi) from the Perseus-Pisces redshift survey, which is now virtually 100\% complete for all morphological types to m_B = 15.5. We detect strong distortions of the iso-correlation contours

Jim Friar

The impact of chiral symmetry on nuclear physics is discussed in the context of recent advances in the few-nucleon systems and of dimensional power counting. The tractability of few-nucleon calculations, illustrated by very recent solutions for $A = 2-6$, is shown to follow from power counting based on chiral Lagrangians. The latter predicts the suppression

Swapna Mahapatra, Karmadeva Maharana, Lambodar P. Singh

We investigate the tachyon-dilaton-metric system to study the "graceful exit" problem in string theoretic inflation, where tachyon plays the role of the scalar field. From the phase space analysis, we find that the inflationary phase does not smoothly connect to a Friedmann-Robertson-Walker (FRW) expanding universe, thereby providing a simple tachyonic exten

C. Adami, C. T. Brown, M. Haggerty

Using an artificial system of self-replicating strings, we show a correlation between the age of a genotype and its abundance that reflects a punctuated rather than gradual picture of evolution, as suggested long ago by Willis. In support of this correlation, we measure genotype abundance distributions and find universal coefficients. Finally, we propose a s

H. Aratyn

Some new developments in constrained Lax integrable systems and their applications to physics are reviewed. After summarizing the tau function construction of the KP hierarchy and the basic concepts of the symmetry of nonlinear equations, more recent ideas dealing with constrained KP models are described. A unifying approach to constrained KP hierarchy based

Neta A. Bahcall

The Sloan Digital Sky Survey (SDSS) will provide a complete imaging and spectroscopic survey of the high-latitude northern sky. The 2D survey will image the sky in five colors and will contain nearly 5 x 107 galaxies to g ~ 23m. The spectroscopic survey will obtain spectra of the brightest 106 galaxies, 105 quasars, and 103.5 rich clusters of galaxies (to g~

Neta A. Bahcall

Rich clusters of galaxies, the largest virialized systems known, provide a powerful tool for the study of cosmology. Some of the fundamental questions that can be addressed with clusters of galaxies include: how did galaxies and large-scale structure form and evolve? What is the amount, composition and distribution of matter in the universe? I review some of

Michael J. Love, Henri J. F. Jansen

The evaluation of Coulomb forces is a difficult task. The summations that are involved converge only conditionally and care has to be taken in selecting the appropriate procedure to define the limits. The Ewald method is a standard method for obtaining Coulomb forces, but this method is rather slow, since it depends on the square of the number of atoms in a

Cayetano Di Bartolo, Rodolfo Gambini, Jorge Griego, Jorge Pullin

This article reviews the status of several solutions to all the constraints of quantum gravity that have been proposed in terms of loops and extended loops. We discuss pitfalls of several of the results and in particular discuss the issues of covariance and regularization of the constraints in terms of extended loops. We also propose a formalism for ``thicke

Afsar Abbas

A lot of theoretical ideas have been floated to explain the so called cold fusion phenomenon. I look at a large subset of these and study further physical implications of the concepts involved. I suggest that these can be tested by other independent physical means. Because of the significance of these the experimentalists are urged to look for these signatur

Eyal Maoz

There is now dynamical evidence for massive dark objects at the center of several galaxies, but suggestions that these are supermassive black holes are based only on indirect astrophysical arguments. The recent unprecedented measurement of the rotation curve of maser emission sources at the center of NGC 4258, and the remarkable discovery that it is Kepleria

L. Dolan, S. Horvath

For the closed superstring, spin fields and bi-spinor states are defined directly in four spacetime dimensions. Explicit operator product expansions are given, including those for the internal superconformal field theory, which are consistent with locality and BRST invariance for the string vertices. The most general BRST picture changing for these fields is

E. V. Shuryak

We discuss available information about the instanton size distribution $d(\rho)$, which comes from lattice simulations and the interacting instanton liquid model. Not only they are remarkably consistent, but one can also reproduce $d(\rho)$ with an alternative idea, based on the infrared fixed point. We show, that lattice non-perturbative beta-function (for

Adel Bilal, Ian. I. Kogan

After giving a pedagogical review of the chiral gauge approach to 2D gravity, with particular emphasis on the derivation of the gravitational Ward identities, we discuss in some detail the interpretation of matter correlation functions coupled to gravity in chiral gauge. We argue that in chiral gauge no {\it explicit} gravitational dressing factor, analogue

R. De Propris, C. J. Pritchet, W. E. Harris, R. D. McClure

Luminosity Functions have been obtained for very faint dwarf galaxies in the cores of four rich clusters of galaxies (Abell 2052, 2107, 2199 and 2666). It is found that the luminosity function of dwarf galaxies rises very steeply in these clusters, with a power-law slope of \alpha -2.2 (down to absolute limiting magnitudes M_I = -13 and M_B = -11 for H_0 = 7