arXiv papers from July 1994

R. B. Laughlin

It is argued that recent Josephson junction and point-contact tunneling experiments, interpreted as intended by their authors, indicate that time-reversal symmetry breaking occurs at surfaces of cuprate superconductors. The variation among experiments and the failure of previous searches to find $T$-violation are ascribed to disorder and effects of 3-dimensi

Michael Luke, Aneesh V. Manohar, Martin J. Savage

We investigate the high-order behavior of perturbative matching conditions in effective field theories. These series are typically badly divergent, and are not Borel summable due to infrared and ultraviolet renormalons which introduce ambiguities in defining the sum of the series. We argue that, when treated consistently, there is no physical significance to

Peter Pflug, Wlodzimierz Zwonek

In the paper we give some necessary conditions for a mapping to be a $\kappa$-geodesic in non-convex complex ellipsoids. Using these results we calculate explicitly the Kobayashi metric in the ellipsoids $\{|z_1|^2+|z_2|^{2m}<1\}\subset\bold C^2$, where $m<\frac12$.

R. Aleksan, A. Le Yaouanc, L. Oliver, O. Pène

To help the difficult determination of the angle $\gamma$ of the unitarity triangle, Aleksan, Dunietz and Kayser have proposed the modes of the type $K^-D^+_s$, common to $B_s$ and $\bar{B}_s$. We point out that it is possible to gain in statistics by a sum over all modes with ground state mesons in the final state, i.e. $K^-D^+_s$, $K^{*-}D_+^s$, $K^-D^{*+}

Stefan Forste

We perform a marginal deformation of the SL(2,R) WZW model in a null direction. If we send the deformation parameter to infinity we obtain a linear dilaton background plus two free bosons. We show in addition that such a background can be obtained by a duality transformation of the undeformed WZW model. In the end we indicate how to generalize the given proc

H. García-Compeán, J. M. López-Romero, M. A. Rodríguez-Segura, M. Socolovsky

We review the elementary theory of gauge fields and the Becchi-Rouet-Stora- Tyutin symmetry in the context of differential geometry. We emphasize the topological nature of this symmetry and discuss a double Chevalley-Eilenberg complex for it.

G. M. D'Ariano, M. Fortunato, P. Tombesi

A new master equation performing isotropic phase-number squeezing is suggested. The phase properties of coherent superpositions are analyzed when the state evolves in presence of a bath with fluctuations squeezed in this isotropic way. We find that such a reservoir greatly improves persistence of coherence with respect to either a customary thermal bath, or

Arturo Trujillo

This paper describes an algorithm for the computation of FIRST and FOLLOW sets for use with feature-theoretic grammars in which the value of the sets consists of pairs of feature-theoretic categories. The algorithm preserves as much information from the grammars as possible, using negative restriction to define equivalence classes. Addition of a simple data

Walter Kob, Hans C. Andersen

We present the results of a large scale molecular dynamics computer simulation of a binary, supercooled Lennard-Jones fluid. At low temperatures and intermediate times the time dependence of the intermediate scattering function is well described by a von Schweidler law. The von Schweidler exponent is independent of temperature and depends only weakly on the

Guy Bonneau

We analyse with the algebraic, regularisation independent, cohomological B.R.S. methods, the renormalisability of torsionless N=2 supersymmetric non-linear $\si$ models built on compact K\"ahler spaces. Surprisingly enough with respect to the common wisdom, we obtain an anomaly candidate, when the Hodge number $h^{3,0}$ of the target space manifold is differ

Scott Chapman, Ulrich Heinz

We clarify the relationship between the current formalism developed by Gyulassy, Kaufmann and Wilson and the Wigner function formulation suggested by Pratt for the 2-particle correlator in Hanbury-Brown Twiss interferometry. When applied to a hydrodynamical description of the source with a sharp freeze-out hypersurface, our results remove a slight error in t

Adi Nusser, Marc Davis

We present a method for deriving a smoothed estimate of the peculiar velocity field of a set of galaxies with measured circular velocities $\eta\equiv {\rm log} \Delta v$ and apparent magnitudes $m$. The method is based on minimizing the scatter of a linear inverse Tully-Fisher relation $\eta= \eta(M)$ where the absolute magnitude of each galaxy is inferred

G. M. D&#39;Ariano, M. Fortunato, P. Tombesi

The evolution of a single mode of the electromagnetic field interacting with a squeezed bath in a Kerr medium is considered. The solution of the corresponding master equation is given numerically. It is argued that the creation of a superposition state (Schrödinger&#39;s cat) is better achieved in presence of a squeezed reservoir than of a thermal one.

B. Fields, K. Olive, D. Schramm

The observed B/Be ratio in extreme Pop II stars has been interpreted as evidence of Be and B synthesis by early galactic cosmic rays. However, a recent reanalysis of the boron abundance in the Pop II halo star HD140283 suggests that B/H may be larger than previously reported, by as much as a factor of 4. This would yield a B/Be ratio lying in the range $14 \

J M Figueroa-O'Farrill, S Stanciu

We summarize some results obtained on the problem of gauging the Wess--Zumino term of a d-dimensional bosonic sigma-model. We show that gauged WZ-like terms are in one-to-one correspondence with equivariant cocycles of the target space. By the same token, the obstructions to gauging a WZ term can be understood in terms of the equivariant cohomology of the ta

Kevin Knight, Steve K. Luk

Knowledge-based machine translation (KBMT) systems have achieved excellent results in constrained domains, but have not yet scaled up to newspaper text. The reason is that knowledge resources (lexicons, grammar rules, world models) must be painstakingly handcrafted from scratch. One of the hypotheses being tested in the PANGLOSS machine translation project i

Kevin Knight, Ishwar Chander

Large amounts of low- to medium-quality English texts are now being produced by machine translation (MT) systems, optical character readers (OCR), and non-native speakers of English. Most of this text must be postedited by hand before it sees the light of day. Improving text quality is tedious work, but its automation has not received much research attention

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

Simply on CP arguments, we argue against a Standard Model explanation of baryogenesis via the charge transport mechanism. A CP-asymmetry is found in the reflection coefficients of quarks hitting the electroweak phase boundary created during a first order phase transition. The problem is analyzed both in an academic zero temperature case and in the realistic

A. Patrascioiu, E. Seiler

This reply tries to rectify some misunderstandings that are in our opinion contained in the Comment by Campostrini and Rossi, <hep-lat 99407008> on our paper <hep-lat 9407003>.

M. Olechowski, S. Pokorski

We discuss radiative electroweak symmetry breaking with non-universal scalar masses at the GUT scale. Large $\tan\beta$ solutions are investigated in detail and it is shown that qualitatively new (as compared to the universal case) solutions exist, with much less correlation between soft terms. We identify two classes of non-universalities which give solutio

Detlef Lohse, Axel Müller-Groeling

Two parametrizations for second order velocity moments, the Batchelor parametrization for the r-space structure function and a common parametrization for the energy spectrum, $E(p)\propto p^{-5/3}\exp(-p/p_d)$, are examined and compared. In particular, we investigate corrections to the local scaling exponents induced by finite size effects. The behavior of l

B. Moussallam

The chiral expansion of the low energy processes $\pi^0\to\gamma\gamma$ and $\eta\to\gamma\gamma$ is reconsidered with particular emphasis on the question of the evaluation of the two low-energy parameters from ${\cal L}^{WZ}_{(6)}$ which are involved at chiral order six. It is shown how extensive use of sum-rules and saturation with resonances as well as co

Glennys R. Farrar

Gluinos in the mass range ~1 1/2 - 3 1/2 GeV are absolutely excluded. Lighter gluinos are allowed, except for certain ranges of lifetime. Only small parts of the mass-lifetime parameter space are excluded for larger masses unless the lifetime is shorter than ~ 2 10^{-11} (m_{gluino}/ GeV) sec. Refined mass and lifetime estimates for R-hadrons are given, pres

Gaetano Fiore

We construct the Euclidean Hopf algebra $U_q(e^N)$ dual of $Fun(\rn_q^N\lcross SO_{q^{-1}}(N))$ by realizing it as a subalgebra of the differential algebra $\DFR$ on the quantum Euclidean space $\rn_q^N$; in fact, we extend our previous realization \cite{fio4} of $U_{q^{-1}}(so(N))$ within $\DFR$ through the introduction of q-derivatives as generators of q-t

Jorg Imhoff

Recomi (REpeated COrrelation Matrix Inversion) is a polynomially fast algorithm for searching optimally stable solutions of the perceptron learning problem. For random unbiased and biased patterns it is shown that the algorithm is able to find optimal solutions, if any exist, in at worst O(N^4) floating point operations. Even beyond the critical storage capa

E. Gabrielli, G. F. Giudice

We study the corrections to $\epsilon^\prime /\epsilon$ in the minimal supersymmetric model at the leading order in QCD and QED. Supersymmetry can increase the standard model prediction for $\epsilon^\prime /\epsilon$ by at most 40\% for $m_t=174$ GeV, an enhancement which is indistinguishable from the present theoretical uncertainties. The most conspicuous

P. H. Damgaard, J. Lacki

We study the pattern of zeros emerging from exact partition function evaluations of Ising spin glasses on conventional finite lattices of varying sizes. A large number of random bond configurations are probed in the framework of quenched averages. This study is motivated by the relationship between hierarchical lattice models whose partition function zeros f

G. M. de Divitiis, R. Frezzotti, M. Guagnelli, R. Petronzio

Through a finite size renormalization group technique we calculate the running coupling constant for quenched SU(2) with a few percent error over a range of energy varying by a factor thirty. The definition is based on ratio of correlations of Polyakov loops with twisted boundary conditions. The extrapolation to the continuum limit is governed by corrections

M. Gourdin, A. N. Kamal, Y. Y. Keum, X. Y. Pham

Using factorization we determine the allowed domains of the ratios of form factors, $x = A_2(0)/A_1(0)$ and $y = V(0)/A_1(0)$, from the experimentally measured ratio $R_h \equiv \Gamma(D_s^+ \ra \phi \rho^+)/\Gamma(D_s^+ \ra \phi \pi^+)$ assuming three different scenarios for the $q^2$-dependence of the form factors. We find that the allowed domains overlap

Dale Gerdemann

This paper presents a unified approach to parsing, in which top-down, bottom-up and left-corner parsers are related to preorder, postorder and inorder tree traversals. It is shown that the simplest bottom-up and left-corner parsers are left recursive and must be converted using an extended Greibach normal form. With further partial execution, the bottom-up a

E. Abdalla, M. C. B. Abdalla

We construct composite operators in two-dimensional bosonized QCD, which obey a $W_\infty$ algebra, and discuss their relation to analogous objects recently obtained in the fermionic language. A complex algebraic structure is unravelled, supporting the idea that the model is integrable. For singlets we find a mass spectrum obeying the Regge behavior.

V. A. Litvin, S. R. Slabospitsky

The $e^{+}\,e^{-}\,\rightarrow\,l^{+}\, \l^{-}\,\gamma\,\gamma$ anomalous events, regis\-te\-red at $L3$ de\-tec\-tor at $e^+ e^-$ $CERN-LEP$ collider have been analysed. It has been shown that the interpretation of such events as a manifestation of scalar (pseudoscalar) resonance with the mass of 60 GeV contradicts other experimental data.

Brian P. Schmidt, Robert P. Kirshner, Bruno Leibundgut, Lisa A. Wells

We have obtained photometry and spectra of SN~1991T which extend more than 1000 days past maximum light, by far the longest a SN~Ia has been followed. Although SN~1991T exhibited nearly normal photometric behavior in the first 400 days following maximum, by 600 days its decline had slowed, and by 950~days the supernova brightness was consistent with a consta

Walter Kob, Hans C. Andersen

We report the results of a molecular dynamics simulation of a supercooled binary Lennard-Jones mixture. By plotting the self intermediate scattering functions vs. rescaled time, we find a master curve in the $\beta$-relaxation regime. This master curve can be fitted well by a power-law for almost three decades in rescaled time and the scaling time, or relaxa

M. Diehl

We investigate the production of a quark-antiquark pair in diffractive photon- proton scattering, approximating soft pomeron exchange by the exchange of two nonperturbative gluons. In deep inelastic scattering at HERA, events with two jets and the scattered proton in the final state are predicted to be observa- ble, with an important contribution from charm

C. Alexandrou, A. Borrelli, S. Güsken, F. Jegerlehner

We perform a lattice study of heavy baryons, containing one ($\Lambda_b$) or two $b$-quarks ($\Xi_b$). Using the quenched approximation we obtain for the mass of $\Lambda_b$ $$ M_{\Lambda_b}= 5.728 \pm 0.144 \pm 0.018 {\rm GeV}.$$ The mass splitting between the $\Lambda_b$ and the B-meson is found to increase by about 20\% if the light quark mass is varied f

Edwin Langmann, Jouko Mickelsson

We discuss 2-cocycles of the Lie algebra $\Map(M^3;\g)$ of smooth, compactly supported maps on 3-dimensional manifolds $M^3$ with values in a compact, semi-simple Lie algebra $\g$. We show by explicit calculation that the Mickelsson-Faddeev-Shatashvili cocycle $\f{\ii}{24\pi^2}\int\trac{A\ccr{\dd X}{\dd Y}}$ is cohomologous to the one obtained from the cocyc

F. Farchioni, A. Papa

We study the role of small-size instantons in the determination of the topological susceptibility of the 2-d $O(3) \: \sigma $ model on the lattice. In particular, we analyze how they affect the non-perturbative determination, by Monte Carlo techniques, of the renormalizations on the lattice. As a result, we obtain a high-precision non-perturbative determina

Ewa Luiza Lokas, Roman Juszkiewicz, David Weinberg, Francois Bouchet

An attractive and simple hypothesis for the formation of large-scale structure is that it developed by gravitational instability from primordial fluctuations with an initially Gaussian probability distribution. Non-linear gravitational evolution drives the distribution away from the Gaussian form, generating measurable skewness and kurtosis even when the var

A. Klemm, B. H. Lian, S. S. Roan, S. -T. Yau

We give close formulas for the counting functions of rational curves on complete intersection Calabi-Yau manifolds in terms of special solutions of generalized hypergeometric differential systems. For the one modulus cases we derive a differential equation for the Mirror map, which can be viewed as a generalization of the Schwarzian equation. We also derive

M. Harada, Y. Kikukawa, T. Kugo, H. Nakano

In the leading order of a modified 1/Nc expansion, we show that a class of gauge-Higgs-Yukawa systems in four dimensions give non-trivial and well-defined theories in the continuum limit. The renormalized Yukawa coupling y and the quartic scalar coupling \lambda have to lie on a certain line in the (y,\lambda) plane and the line terminates at an upper bound.

C. Garcia-Recio, J. Nieves, E. Oset

A careful reanalysis is done of the contribution to $K^{+}$ nucleus scattering from the interaction of the kaon with the virtual pion cloud. The usual approximations made in the evaluation of the related kaon selfenergy are shown to fail badly. We also find new interaction mechanisms which provide appreciable corrections to the kaon selfenergy. Some of these

R. Lima, R. Vilela Mendes

Velocity increments over a distance r and turbulent energy dissipation on a box of size r are well described by the multifractal models of fully developed turbulence. These quantities and models however, do not involve time-correlations and therefore are not a detailed test of the dynamics of the turbulent cascade. If the time development of the turbulent ca

Max-Olivier Hongler, Ricardo Lima

We construct a coupled set of nonlinear reaction-diffusion equations which are exactly solvable. The model generalizes both the Burger equation and a Boltzman reaction equation recently introduced by Th. W. Ruijgrok and T. T. Wu.

Kemal Oflazer, Ilker Kuruoz

Automatic text tagging is an important component in higher level analysis of text corpora, and its output can be used in many natural language processing applications. In languages like Turkish or Finnish, with agglutinative morphology, morphological disambiguation is a very crucial process in tagging, as the structures of many lexical forms are morphologica

Kevin Krisciunas, Roger F. Griffin, Edward F. Guinan, Kenneth D. Luedeke

We present further photometric observations of the unusual F0 V star 9 Aurigae and present evidence that this star's radial velocity, spectroscopic line widths and line depths are also variable with the same frequencies as the photometric data ($f_1 \approx 0.795$ and $f_2 \approx 0.345$ d$^{-1}$). The phases of these sinusoids are stable over time scales of

Omar Foda, Yas-Hiro Quano

Presented are polynomial identities which imply generalizations of Euler and Rogers--Ramanujan identities. Both sides of the identities can be interpreted as generating functions of certain restricted partitions. We prove the identities by establishing a graphical one-to-one correspondence between those two kinds of restricted partitions.

Yang XIAN

Quantum spin-lattice systems in low dimensions exhibit a variety of interesting zero-temperature phases, some of which show non-classical (i.e., non-magnetic) long-range orders, such as dimer or trimer valence-bond order. These symmetry-breaking systems with localized valence bonds are referred to as valence-bond lattices (VBL) in this article. A review of o

Brian P. Schmidt Robert P. Kirshner, Ronald G. Eastman, Mark M. Phillips, Nicholas B. Suntzeff

We have used observations gathered at CTIO to measure distances by the Expanding Photosphere Method (EPM) to 5 Type II supernovae. These supernovae lie at redshifts from cz = 1100 km/s to z = 5500 km/s, and increase to 18 the number of distances measured using EPM. We compare distances derived to 11 Type II supernovae with distances to their host galaxies me

Bohdan Paczynski

The microlensing of background stars by compact objects in globular clusters is analyzed. The main strength of the proposed search is the direct relationship between the lens mass and the time scale of the microlensing event. The main problem is the low overall rate of expected events which implies that a ground based search should last for about a decade to

A. D. Dolgov, K. Kainulainen, I. Z. Rothstein

We derive new bounds on the Dirac mass of the tau and muonic neutrinos. By solving the kinetic equation for the rate of energy deposition due to helicity flipping processes and imposing the constraint that the number of effective species contributing to the energy density at the time of nucleosynthesis be $\Delta k_\nu<~0.3$, we find the bounds $m_{\nu_\mu}

Carolyn Penstein Rose', Alex Waibel

We describe an implementation of a hybrid statistical/symbolic approach to repairing parser failures in a speech-to-speech translation system. We describe a module which takes as input a fragmented parse and returns a repaired meaning representation. It negotiates with the speaker about what the complete meaning of the utterance is by generating hypotheses a

A. Duncan, E. Eichten, J. Flynn, B. Hill

The results of an extensive study of B-meson properties in quenched lattice QCD are presented. The studies are carried out in the static quark limit where the b-quark is taken to be infinitely massive. Our computations rely on a multistate smearing method introduced previously, with smearing functions generated from a relativistic lattice quark model. System

R. W. Nunes, David Vanderbilt

We present a generalization of the Li, Nunes and Vanderbilt density-matrix method to the case of a non-orthogonal set of basis functions. A representation of the real-space density matrix is chosen in such a way that only the overlap matrix, and not its inverse, appears in the energy functional. The generalized energy functional is shown to be variational wi

Nathan Berkovits, Cumrun Vafa

We show how to make a topological string theory starting from an $N=4$ superconformal theory. The critical dimension for this theory is $\hat c= 2$ ($c=6$). It is shown that superstrings (in both the RNS and GS formulations) and critical $N=2$ strings are special cases of this topological theory. Applications for this new topological theory include: 1) Provi

E. Brézin, A. Zee

We study a new class of matrix models, formulated on a lattice. On each site are $N$ states with random energies governed by a Gaussian random matrix Hamiltonian. The states on different sites are coupled randomly. We calculate the density of and correlation between the eigenvalues of the total Hamiltonian in the large $N$ limit. We find that this correlatio

Sonia Stanciu

This thesis is roughly organized into two parts. The first one (the first three chapters), expository in nature, attempts to place the current work in context: at first historically, but then focusing on the Lax formalism and the Adler--Gel'fand--Dickey scheme for hierarchies of the KdV type. The second part (the last four chapters) comprises the main body o

C. F. Baillie, D. A. Johnston, J-P. Kownacki

The Ising model on ``thin'' graphs (standard Feynman diagrams) displays several interesting properties. For ferromagnetic couplings there is a mean field phase transition at the corresponding Bethe lattice transition point. For antiferromagnetic couplings the replica trick gives some evidence for a spin glass phase. In this paper we investigate both the ferr

George Jikia

We study the signals and backgrounds for a heavy Higgs boson in the processes $\gamma\gamma\to WWWW$, $\gamma\gamma\to WWZZ$ at the photon linear collider. The results are based on the complete tree level SM calculation for these reactions. We show that the invariant mass spectrum of central $WW$, $ZZ$ pairs is sensitive to the signal from Higgs boson with a

Wayne Hu, Naoshi Sugiyama

We introduce a simple yet powerful {\it analytic} method which obtains the structure of cosmic microwave background anisotropies to better than 5-10\% in temperature fluctuations on {\it all} scales. It is applicable to {\it any} model in which the potential fluctuations at recombination are both linear and known. Moreover, it recovers and explains the prese

Matthias Neubert, Chris T. Sachrajda

Recently, it has been shown that the concept of the pole mass of a heavy quark becomes ambiguous beyond perturbation theory, because of the presence of infrared renormalons. We argue that the predictions of heavy quark effective theory, whose construction is based on the pole mass, are free of such ambiguities. In the $1/m_Q$ expansion of physical quantities

Yutaka Hosotani

In a class of three-dimensional abelian gauge theory the Lorentz invariance is spontaneously broken by dynamical generation of a magnetic field. An originally topologically massive photon becomes gapless, i.e. p_0=0 at {\vec p}=0. Indeed, the photon is the Nambu-Goldstone boson associated with the spontaneous breaking of the Lorentz invariance. Although symm

C. Kuebert, A. Muramatsu

A quantitative description of the transition to a quantum disordered phase in a doped antiferromagnet is obtained with a U(1) gauge-theory, where the gap in the spin-wave spectrum determines the strength of the gauge-fields. They mediate an attractive long-range interaction whose possible bound-states correspond to charge-spin separation and pairing.

G. L. Israel, S. Mereghetti, L. Stella

We discovered a periodicity at about 8.7s from the X--ray sources 4U0142+61, previously considered a possible black hole candidate on the basis of its ultrasoft spectrum. The pulsations are visible only in the 1--4 keV energy range, during an observation obtained with the EXOSAT satellite in August 1984. A search for delays in the pulse arrival times caused

A. Chamorro, K. S. Virbhadra

It is known that certain properties of charged dilaton black holes depend on a free parameter $\beta$ which controls the strength of the coupling of the dilaton to the Maxwell field. We obtain the energy associated with static spherically symmetric charged dilaton black holes for arbitrary value of the coupling parameter and find that the energy distribution

I. Ya. Korenblit

We employ the Schwinger boson mean-field approach to study the effects of arbitrary frustrated bonds and plaquettes (formed from four frustrated bonds) in two-dimensional ferro- and antiferromagnets on the spin-wave spectrum and the correlation length at finite temperatures. We distinguish between strongly frustrated bonds (plaquettes), when the frustrated c

E. N. Rodionov

We build a model which is based on the assumption that the {\bf c} and {\bf s,b} quarks are excited states of {\bf u} and {\bf d} quarks. This model predicts the non-existence of the {\bf top} quark and estimates the size of the quarks to be of order $10^{-7}$ fm.

B. de Carlos, M. Moretti

We study the structure of soft breaking terms in the context of a gaugino condensation scenario. Assuming that the Supergravity Lagrangian is the correct quantum field theory limit, at some momentum scale $\mu_{UV}$, of a more fundamental one, we demonstrate that the correct result is obtained simply by substituting, in the tree level Supergravity Lagrangian

M. R. Gaberdiel

It is shown how a chiral Wess-Zumino-Witten theory with globally defined vertex operators and a one-to-one correspondence between fields and states can be constructed. The Hilbert space of this theory is the direct sum of tensor products of representations of the chiral algebra and finite dimensional internal parameter spaces. On this enlarged space there ex

T. Christodoulakis, E. Korfiatis, E. C. Vagenas

We consider the quantization of a general spatially homogeneous space-time belonging to an arbitrary but fixed Class A Bianchi type. Exploiting the information furnished by the quantum version of the momentum constraints, we use as variables the two simplest contractions of $C^{\alpha}_{\beta \gamma}$ and $\gamma_{\alpha \beta}$ as well as the determinant of

H. Arisue, K. Tabata

We extend low-temperature series for the second moment of the correlation function in $d=3$ simple-cubic Ising model from $u^{15}$ to $u^{26}$ using finite-lattice method, and combining with the series for the susceptibility we obtain the low-temperature series for the second-moment correlation length to $u^{23}$. An analysis of the obtained series by inhomo

Robert S. Maier, Daniel L. Stein

Consider a two-dimensional continuous-time dynamical system, with an attracting fixed point $S$. If the deterministic dynamics are perturbed by white noise (random perturbations) of strength $\epsilon$, the system state will eventually leave the domain of attraction $\Omega$ of $S$. We analyse the case when, as $\epsilon\to0$, the exit location on the bounda

R. G. Mints, I. B. Snapiro

We consider a one-dimensional Josephson junction in a superconducting film with the thickness that is much less than the London penetration depth. We treat an electromagnetic wave propagating along this tunnel contact. We show that the electrodynamics of a Josephson junction in a thin film is nonlocal if the wave length is less than the Pearl penetration dep

Shinji Ejiri, Shun-ichi Kitahara, Yoshimi Matsubara, Tsuneo Suzuki

Monopole and photon contributions to abelian Wilson loops are calculated using Monte-Carlo simulations of finite-temperature $SU(2)$ QCD in the maximally abelian gauge. Long monopole loops alone are responsible for the behavior of the string tension in the confinement phase up to the critical $\beta_c$. Short monopole loops and photons do not contribute to t

Alec Maassen van den Brink, H. Dekker

The calculation of the Kapitza boundary resistance between dissimilar harmonic solids has since long (Little [Can. J. Phys. 37, 334 (1959)]) suffered from a paradox: this resistance erroneously tends to a finite value in the limit of identical solids. We resolve this paradox by calculating temperature differences in the final heat-transporting state, rather

Michal Kurzynski

The theory of biochemical processes needs simple but realistic models of phenomena underlying microscopic dynamics of proteins. Many experiments performed in the 1980s have demonstrated that within the protein native state, apart from usual vibrational dynamics, a rich interconformational (activated) dynamics exists. The slowness of this dynamics makes any c

Matthias Bartelmann

The angular two-point correlation function between background QSOs and foreground galaxies induced by gravitational lensing is derived. It is shown that the shape of this correlation function depends sensitively on the spectrum of the density fluctuations in the Universe, thus providing a possibility to distinguish between different models for the spectrum.

Erich Poppitz, Lisa Randall

We derive the supersymmetric low-energy effective theory of the D-flat directions of a supersymmetric gauge theory. The Kahler potential of Affleck, Dine and Seiberg is derived by applying holomorphic constraints which manifestly maintain supersymmetry. We also present a simple procedure for calculating all derivatives of the Kahler potential at points on th

S. Flach, K. Kladko, C. R. Willis

We analyze the origin and features of localized excitations in a discrete two-dimensional Hamiltonian lattice. The lattice obeys discrete translational symmetry, and the localized excitations exist because of the presence of nonlinearities. We connect the presence of these excitations with the existence of local integrability of the original N degree of free

Aleksandar Kocic, John Kogut

Large-N expansions and computer simulations indicate that the universality class of the finite temperature chiral symmetry restoration transition in the 3D Gross-Neveu model is mean field theory. This is a counterexample to the standard 'sigma model' scenario which predicts the 2D Ising model universality class. We trace the breakdown of the standard scenari

Dekang Lin

We present an efficient, broad-coverage, principle-based parser for English. The parser has been implemented in C++ and runs on SUN Sparcstations with X-windows. It contains a lexicon with over 90,000 entries, constructed automatically by applying a set of extraction and conversion rules to entries from machine readable dictionaries.

Adam Doliwa, Paolo Maria Santini

We show that the following elementary geometric properties of the motion of a discrete (i.e. piecewise linear) curve select the integrable dynamics of the Ablowitz-Ladik hierarchy of evolution equations: i) the set of points describing the discrete curve lie on the sphere S^3, ii) the distance between any two subsequant points does not vary in time, iii) the

Franz E. Schunck, Eckehard W. Mielke

The mechanism of the initial inflation of the universe is based on gravitationally coupled scalar fields $\phi$. Various scenarios are distinguished by the choice of an {\it effective self--interaction potential} $U(\phi)$ which simulates a {\it temporarily} non--vanishing {\em cosmological term}. Using the Hubble expansion parameter $H$ as a new ``time" coo

M. Stoilov, R. Zaikov

The central extension of a new infinite dimensional algebra which has both $W_\infty$ and affine $sl(2,R)$ as subalgebras is found. The critical dimension of the corresponding string model is $D=5$.

Helen Au-Yang, Jacques H. H. Perk

In honor of Onsager's ninetieth birthday, we like to review some exact results obtained so far in the chiral Potts models and to translate these results into language more transparent to physicists, so that experts in Monte Carlo calculations, high and low temperature expansions, and various other methods, can use them. We shall pay special attention to the

R. N. Mohapatra, S. Nussinov

We point out the following astrophysical consequences of a tau neutrino with mass in the MeV range: (i) if it has a small electric charge which will allow it to become a cold dark matter of the universe, then present limits on the 511 KeV gamma ray line rule out the possibility that it contributes an $\Omega_{\nu_{\tau}}$ between .1 to 1 making it unsuitable

L. A. Ford, D. L. Band, J. L. Matteson, M. S. Briggs

We investigate spectral evolution in 37 bright, long gamma-ray bursts observed with the BATSE Spectroscopy Detectors. High resolution spectra are characterized by the energy of the peak of \nfn~and the evolution of this quantity is examined relative to the emission intensity. In most cases it is found that this peak energy either rises with or slightly prece

Robert J. Scherrer, Robert K. Schaefer

The Sachs-Wolfe temperature fluctuations produced by primordial density perturbations are proportional to the potential field \phi, which is a weighted integral over the density field \delta. Because of the central limit theorem, \phi can be approximately Gaussian even when \delta is non-Gaussian. Using the Wold representation for non-Gaussian density fields

D. P. Roy, K. Sridhar

We study the process $\bar p p \rightarrow J/\psi + \gamma +X$ at the Tevatron energy ($\sqrt{s} = 1.8$~TeV). The perturbative QCD contributions to this process from the gluon-fusion and the fragmentation mechanisms are computed. For the entire range of $p_T$ that can be probed at the Tevatron, the fusion contribution is found to be dominant. Consequently th

J. J. Halliwell

I review the decoherent (or consistent) histories approach to quantum mechanics, due to Griffiths, to Gell-Mann and Hartle, and to Omnes. This is an approach to standard quantum theory specifically designed to apply to genuinely closed systems, up to and including the entire universe. It does not depend on an assumed separation of classical and quantum domai

D. L. Welch

The advantages of a near-infrared variant of the Barnes-Evans method for estimating distances to Cepheid variables are described and quantified. A surface brightness-color relation for $K$ photometry and the $(V-K)_0$ color index is established using modern, high-precision angular diameters from optical interferometers. Applied to data for the galactic (clus

H. C. Eggers, P. Lipa

Higher order correlation measurements involve multiple event averages which must run over unequal events to avoid statistical bias. We derive correction formulas for small event samples, where the bias is largest, and utilize the results to achieve savings in CPU time consumption for the star integral. Results from a simple model of correlations illustrate t

S. J. Wallace, Franz Gross, J. A. Tjon

Scalar and vector interactions, with the scalar interaction coupled to a composite spin-1/2 system so as to cause a shift of its mass, are shown to obey a low-energy theorem which guarantees that the second order interaction due to z-graphs is the same as for a point Dirac particle. Off-shell and contact interactions appropriate to the composite system cance

J. A. Casas, J. R. Espinosa, M. Quirós, A. Riotto

We compute the upper bound on the mass of the lightest Higgs boson in the Minimal Supersymmetric Standard Model in a model-independent way, including leading (one-loop) and next-to-leading order (two-loop) radiative corrections. We find that (contrary to some recent claims) the two-loop corrections are negative with respect to the one-loop result and relativ

P. S. Howe, G. Papadopoulos, P. C. West

A class of algebras is constructed using free fermions and the invariant antisymmetric tensors associated with irreducible holonomy groups. (This version contains minor typographical corrections and some additional references. )

B. Bajc, S. Fajfer, R. J. Oakes

Combining heavy quark effective theory and the chiral Lagrangian approach we investigate radiative decays of pseudoscalar $D$ mesons. We first reanalyse $D^{*} \rightarrow D \gamma$ decays within the effective Lagrangian approach using heavy quark spin symmetry, chiral symmetry Lagrangian, but including also the light vector mesons. We then investigate $D \r

O. Coussaert, M. Henneaux

All the causally regular geometries obtained from (2+1)-anti-de Sitter space by identifications by isometries of the form $P \rightarrow (\exp \pi\xi) P$, where $\xi$ is a self-dual Killing vector of $so(2,2)$, are explicitely constructed. Their remarkable properties (Killing vectors, Killing spinors) are listed. These solutions of Einstein gravity with nega

V A Khoze

In the events of the type $e^+e^- \rightarrow W^+W^- \rightarrow$ 4 jets, $e^+e^- \rightarrow t\bar{t} \rightarrow bW^+\bar{b}W^-$, particle production could depend in a non-trivial way on the kinematics of the process. It is shown that QCD interference effects are negligible for energetic perturbative emission, but soft perturbative gluons and non-perturbat

Gabriele Migliorini, Felix Ritort

We have investigated the nature of the dynamical behaviour in low autocorrelation binary sequences. These models do have a glass transition $T_G$ of a purely dynamical nature. Above the glass transition the dynamics is not fully ergodic and relaxation times diverge like a power law $\tau\sim (T-T_G)^{-\gamma}$ with $\gamma$ close to $2$. Approaching the glas

Oleg Andreev

The $\beta\gamma$ system is generalized by complex(rational) powers of the fields, which leads to a corresponding extension on the Fock space. Two different approaches to compute the Green functions of the physical operators are proposed. First the complex(rational) powers are defined via an integral representation,that allows to compute the conformal blocks