January 1997 arXiv papers — page 14

John H. Schwarz

A recent result concerning interacting theories of self-dual tensor gauge fields in six dimensions is generalized to include coupling to gravity. The formalism makes five of the six general coordinate invariances manifest, whereas the sixth one requires a non-trivial analysis. The result should be helpful in formulating the world-volume action of the M theor

Y. Kikukawa, R. Narayanan, H. Neuberger

An argument is presented for a certain universality of finite size corrections in two dimensional gauge theories. In the abelian case a direct calculation is carried out for a particular chiral model. The analytical result confirms the above universality and that the 't Hooft vertex previously measured using the overlap smoothly approaches the correct co

A. Ferrando, A. Jaramillo, S. Shabanov, .

Gluodynamics in 3D spacetime with one spatial direction compactified into a circle of length $L$ is studied. The confinement order parameters, such as the Polyakov loops, are analyzed in both the limits $L \to 0$ and $L \to \infty$. In the latter limit the behavior of the confinement order parameters is shown to be described by a 2D non-linear sigma-model on

C. J. Horowitz, J. Piekarewicz

Core collapse supernovae are dominated by weakly interacting neutrinos. This provides a unique opportunity for macroscopic parity violation. We speculate that parity violation in a strong magnetic field can lead to an asymmetry in the explosion and a recoil of the newly formed neutron star. We estimate the asymmetry from neutrino-polarized-neutron elastic sc

J. Gluza

The possibility of detecting heavy neutrinos (M_N>M_Z) in the NLC is examined.

Miguel A. Sanchis-Lozano, Beatriz Cano-Coloma

We firstly re-examine hadroproduction of prompt J/psi's at the Fermilab Tevatron finding that those colour-octet matrix elements presented in literature are systematically overestimated due to the overlooking of the effective primordial transverse momentum of partons (i.e. dynamically generated via initial-state radiation). We estimate the size of these

Andrzej Bialas, Wieslaw Czyz, Wojciech Florkowski

We calculate shadowing in the process of deep inelastic interactions of leptons with nuclei in the perturbative regime of QCD. We find appreciable shadowing for heavy nuclei (e.g. Pb) in the region of small Bjorken scaling variable $10^{-5}\leq x \leq 10^{-3}$. This shadowing depends weakly on $Q^2$, but it may be strongly influenced, especially at $x \geq 1

Tai An, Chao Wei Qin, Yao Xiao Xia

When the cross section of J/psi production is considered varying with the energy of the nucleon-nucleon interaction the production of J/psi in pA and AA collisions has been studied using FRITIOF Model. The calculation shows that the cross section of J/psi production "per nucleon-nucleon collision" decreases with increasing mass number and centrality

William A. Hiscock, Shane L. Larson, Paul R. Anderson

First-order semiclassical perturbations to the Schwarzschild black hole geometry are studied within the black hole interior. The source of the perturbations is taken to be the vacuum stress-energy of quantized scalar, spinor, and vector fields, evaluated using analytic approximations developed by Page and others (for massless fields) and the DeWitt-Schwinger

W. Metzner, C. Castellani, C. Di Castro

We review the theory of interacting Fermi systems whose low-energy physics is governed by forward scattering, i.e. scattering processes generated by effective interactions with small momentum transfers. These systems include Fermi liquids as well as several important non-Fermi liquid phases: one-dimensional Luttinger liquids, systems with long-range interact

R. Surman, J. Engel, J. R. Bennett, B. S. Meyer

We use network calculations of r-process nucleosynthesis to explore the origin of the peak in the solar r-process abundance distribution near nuclear mass number A = 160. The peak is due to a subtle interplay of nuclear deformation and beta decay, and forms not in the steady phase of the r-process, but only just prior to freezeout, as the free neutrons rapid

Jeremy Goodman, Siang Peng Oh

The turbulent viscosity of convection is believed to circularize the orbits of close binary stars. When the tidal period is shorter than the turnover time of the largest eddies, turbulent viscosity is believed to be suppressed. The degree of suppression is disputed. We re-examine these beliefs via direct perturbative calculations, linearizing the fluid equat

S. Aalto, Simon J. E. Radford, N. Z. Scoville, A. I. Sargent

High resolution observations of 12CO (2.''3), 13CO (3.''9), and HCN (5.''4) J=1--0 in the galaxy merger Arp 299 (IC 694 and NGC 3690) show the line ratios vary dramatically across the system. The 12CO/13CO ratio is unusually large, 60 +- 15, at the IC 694 nucleus, where 12CO emission is very strong, and much smaller, 10 +- 3, in the s

Gastao B. Lima Neto, Frank W. Baier

We have performed N-body simulations of poor clusters with enough particles to resolve the individual galaxies. The main cases of initial conditions are: (i) 50 equal mass galaxies; (ii) 60 galaxies with masses drawn from a Schechter distribution function, and (iii) the collision of two subclusters each one containing 25 galaxies. The evolution and kinematic

R. de la Fuente Marcos

This paper is the fourth one of a series whose chief objective is studying the influence of different mass spectra on the dynamical evolution of open star clusters. Results from several N-body calculations with primordial binaries and mass loss due to stellar evolution are presented. The models show significant differences with those for primordial binaries

Leo Radzihovsky, John Toner

We show that a smectic in a disordered medium (e.g., aerogel) exhibits anomalous elasticity, with the compression modulus B(k) vanishing and the bend modulus K(k) diverging as k --> 0. In addition, the effective disorder develops long ranged correlations. These divergences are much stronger than those driven by thermal fluctuations in pure smectics, and are

J. F. DiTusa, K. Friemelt, E. Bucher, G. Aeppli

We have observed the metal-insulator transition in the strongly correlated insulator FeSi with the chemical substitution of Al at the Si site. The magnetic susceptibility, heat capacity, and field dependent conductivity are measured for Al concentrations ranging from 0 to 0.08. For concentrations greater than 0.01 we find metallic properties quantitatively s

A. Leviatan, R. Bijker

We report on recent calculations of electromagnetic elastic form factors, helicity amplitudes and strong decay widths of N* resonances. The calculations are done in a collective constituent model for the nucleon, in which the resonances are interpreted as rotations and vibrations of an oblate top with a prescribed distribution of charges and magnetization.

A. H. Bougourzi, A. Sebbar

We consider the algebra isomorphism found by Frenkel and Ding between the RLL and the Drinfeld realizations of $U_q(\widehat{gl(2)})$. After we note that this is not a Hopf algebra isomorphism, we prove that there is a unique Hopf algebra structure for the Drinfeld realization so that this isomorphism becomes a Hopf algebra isomorphism. Though more complicat

A. H. Bougourzi

Using the spinon picture we derive an integral representation for the exact n-spinon dynamic structure factor of the spin-1/2 Heisenberg model.

R. M. Santilli

We identify a number of problematic aspects of current classical and quantum theories of antimatter; we introduce a new mathematical formalism which is an antiautomorphic image of that of matter equivalent to charge conjugation at the operator level, but applicable from Newton's equations to quantum mechanics; we show that the emerging new theory of anti

Yuhai Tu

A theoretical model for studying pattern formation in electroconvection is proposed in the form of a modified Swift-Hohenberg equation. A localized state is found in two dimension, in agreement with the experimentally observed ``worm" state. The corresponding one dimensional model is also studied, and a novel stationary localized state due to nonadiabati

Attila Csoto, G. M. Hale

We study the first excited state of He4 in a microscopic {H3+p,He3+n} cluster model, including H3 and He3 distortions. The phenomenological 1S0 H3+p scattering phase shift is well reproduced. We localize a complex pole of the S-matrix between the H3+p and He3+n thresholds. The corresponding resonance parameters are E_r=93 keV position relative to H3+p, and G

V. D. Efros, W. Leidemann, G. Orlandini

The longitudinal (e,e') response function of 4He is calculated precisely with full final state interaction. The explicit calculation of the four-body continuum states is avoided by the method of integral transforms. Precision tests of the response show the high level of accuracy. Non-relativistic nuclear dynamics are used. The agreement with experimental

W. E. Ormand

Coulomb energy differences between mirror nuclei with $A \le 70$ are calculated within the framework of the nuclear shell model using an effective Coulomb plus isovector and isotensor interaction. Absolute binding energies for proton-rich nuclei are predicted by adding the calculated Coulomb shifts to experimentally measured binding energies for the neutron-

W. E. Ormand, P. F. Bortignon, R. A. Broglia

Procedures for projecting angular momentum in a model describing a hot nucleus that takes into account large-amplitude quadrupole fluctuations are discussed. Particular attention is paid to the effect angular-momentum projection has on the observables associated with the $γ$-decay of the giant-dipole resonance (GDR). We also elaborate on which of the differe

Robert Coleman, Adrian Iovita

In this paper, we give explicit descriptions of Hyodo and Kato's Frobenius and Monodromy operators on the first $p$-adic de Rham cohomology groups of curves and Abelian varieties with semi-stable reduction over local fields of mixed characteristic. This paper was motivated by the first author's paper "A $p$-adic Shimura isomorphism and periods of

Christos A. Athanasiadis

Monotone path polytopes arise as a special case of the construction of fiber polytopes, introduced by Billera and Sturmfels. A simple example is provided by the permutahedron, which is a monotone path polytope of the standard unit cube. The permutahedron is the zonotope polar to the braid arrangement. We show how the zonotopes polar to the cones of certain d

John M. Cornwall

We study the factorial divergences of Euclidean $ϕ^3_5$, a problem with connections both to high-energy multiparticle scattering in d=4 and to d=3 (or high-temperature) gauge theory, which like $ϕ^3_5$ is infrared-unstable and superrenormalizable. At large external momentum p (or small mass M) and large order N one might expect perturbative bare skeleton gra

Jules Beckers

Supersymmetric and parasupersymmetric quantum mechanics are now recognized as two further parts of quantum mechanics containing a lot of new informations enlightening (solvable) physical applications. Both contents are here analysed in connection with generalized quantum deformations. In fact, the parasupersymmetric context is visited when the order of paraq

M. Zyskin

We consider d-dimensional Riemanian manifolds which admit d-2 commuting space-like Killing vector fields, orthogonal to a surface, containing two one-parametric families of light-like curves. The condition of the Ricci tensor to be zero gives Ernst equations for the metric. We write explicitly a family of local solutions of this equations corresponding to ar

J. D. Vergados, T. S. Kosmas

We calculate LSP-nucleus elastic scattering cross sections using some representative input in the restricted SUSY parameter space. The coherent matrix elements are computed throughout the periodic table while the spin matrix elements for the proposed $^{207}Pb$ target which has a rather simple nuclear structure. The results are compared to those given from o

T. S. Kosmas, J. D. Vergados

The momentum transfer dependence of the total cross section for elastic scattering of cold dark matter candidates, i.e. lightest supersymmetric particle (LSP), with nuclei is examined. The presented calculations of the event rates refer to a number of representative nuclear targets throughout the periodic table and have been obtained in a relatively wide phe

J. D. Vergados, T. S. Kosmas

The momentum transfer dependence of the LSP-nucleus elastic scattering cross sections is studied. New imput SUSY parameters obtained in a phenomenologically allowed parameter space are used to calculate the coherent rate for various nuclear systems and the spin matrix elements for the proposed $^{207}Pb$ target. The results are compared to those obtained fro

Fred Cooper

We review the assumptions and domain of applicability of Landau's Hydrodynamical Model. By considering two models of particle production, pair production from strong electric fields and particle production in the linear sigma model, we demonstrate that many of Landau's ideas are verified in explicit field theory calculations.

A. Riotto

At the end of inflation the Universe is frozen in a near zero-entropy state with energy density in a coherent scalar field and must be "defrosted" to produce the observed entropy and baryon number. Baryon asymmetry may be generated by the decay of supermassive Grand Unified Theory (GUT) bosons produced non-thermally in a preheating phase after inflat

S. M. Troshin, N. E. Tyurin

We note that it is premature to make a conclusion on the multiplicity of the Pomerons on the basis of the available experimental data since the interactions have a preasymptotic nature

A. G. Galstyan, M. E. Raikh

We consider the network model of the integer quantum Hall effect transition. By generalizing the real--space renormalization group procedure for the classical percolation to the case of quantum percolation, we derive a closed renormalization group (RG) equation for the universal distribution of conductance of the quantum Hall sample at the transition. We fin

E. Nogueira, S. Coutinho, F. D. Nobre, E. M. F. Curado

The multifractal properties of the Edwards-Anderson order parameter of the short-range Ising spin glass model on d=3 diamond hierarchical lattices is studied via an exact recursion procedure. The profiles of the local order parameter are calculated and analysed within a range of temperatures close to the critical point with four symmetric distributions of th

Paul Benioff

It was recently shown that a generalization of quantum Turing machines (QTMs), in which potentials are associated with elementary steps or transitions of the computation, generates potential distributions along computation paths of states in some basis B. The distributions are computable and are thus periodic or have deterministic disorder. These generalized

Cristian F. Moukarzel

The equilibrium conditions impose nontrivial geometrical constraints on the configurations that a two-dimensional foam can attain. In the first place, the three centers of the films that converge to a vertex have to be on a line, i.e. all vertices are aligned. Moreover an equilibrated foam must admit a reciprocal figure. This means that it must be possible t

L. P. Pitaevskii

A phenomenological theory of mode collapse-revival for a system with a weak nonlinearity is presented. The theory takes into account fluctuations of the number n of quanta of oscillations. The collapse time $τ_c ^{-1}$ for a mode of frequency $ω_0$ turns out to be $ω_0(\sqrt{n/2}\hbar ω_0 \mid ν\mid)$, where νis a coefficient in a nonlinear correction to the

S. N. Artemenko, A. G. Kobelkov

Simple and physically transparent equations for the linear response of layered superconductors with d-wave symmetry of the order parameter are derived by means of the quasiclassic kinetic theory of superconductivity. Responses to solenoidal and potential electric fields have different frequency dependencies. The conductivity describing the response to the so

Manny Rayner, David Carter

The paper presents an overview of the Spoken Language Translator (SLT) system's hybrid language-processing architecture, focussing on the way in which rule-based and statistical methods are combined to achieve robust and efficient performance within a linguistically motivated framework. In general, we argue that rules are desirable in order to encode dom

Chengxiang Zhai

Interpretation of natural language is inherently context-sensitive. Most words in natural language are ambiguous and their meanings are heavily dependent on the linguistic context in which they are used. The study of lexical semantics can not be separated from the notion of context. This paper takes a contextual approach to lexical semantics and studies the

Michele Bezzi, Franco Celada, Stefano Ruffo, Philip E. Seiden

In this paper we extend the Celada-Seiden (CS) model of the humoral immune response to include infectious virus and cytotoxic T lymphocytes (cellular response). The response of the system to virus involves a competition between the ability of the virus to kill the host cells and the host's ability to eliminate the virus. We find two basins of attraction

Gabor Etesi

A global uniqueness theorem for stationary black holes is proved as a direct consequence of the Topological Censorship Theorem and the topological classification of compact, simply connected four-manifolds.

Masaru Siino

The topologies of event horizons are investigated. Considering the existence of the endpoint of the event horizon, it cannot be differentiable. Then there are the new possibilities of the topology of the event horizon though they are excluded in smooth event horizons. The relation between the topology of the event horizon and the endpoint of it is revealed.

L. K. Balázs, J. Balog, P. Forgács, N. Mohammedi

Coupling constant renormalization is investigated in 2 dimensional sigma models related by non Abelian duality transformations. In this respect it is shown that in the one loop order of perturbation theory the duals of a one parameter family of models, interpolating between the SU(2) principal model and the O(3) sigma model, exhibit the same behaviour as the

Osamu Tsuchiya

Using the method introduced by Grisaru et al., boundary S matrices for the physical excitations of the open Hubbard chain with boundary fields are studied. In contrast to the open supersymmetric t-J model, the boundary S matrix for the charge excitations depend on the boundary fields though the boundary fields do not break the spin-SU(2) symmetry.

David R. Nelson, Ady Stern

The winding of a single polymer in thermal equilibrium around a repulsive cylindrical obstacle is perhaps the simplest example of statistical mechanics in a multiply connected geometry. As shown by S.F. Edwards, this problem is closely related to the quantum mechanics of a charged particle interacting with a Aharonov-Bohm flux. In another development, Polloc

S. Majid

We introduce a quantum double quasitriangular quasi-Hopf algebra $D(H)$ associated to any quasi-Hopf algebra $H$. The algebra structure is a cocycle double cross product. We use categorical reconstruction methods. As an example, we recover the quasi-Hopf algebra of Dijkgraaf, Pasquier and Roche as the quantum double $D^ϕ(G)$ associated to a finite group $G$

Charles H. Bennett, Ethan Bernstein, Gilles Brassard, Umesh Vazirani

Recently a great deal of attention has focused on quantum computation following a sequence of results suggesting that quantum computers are more powerful than classical probabilistic computers. Following Shor's result that factoring and the extraction of discrete logarithms are both solvable in quantum polynomial time, it is natural to ask whether all of

S. Majid

We consider some general aspects of the new noncommutative or quantum geometry coming out of the theory of quantum groups, in connection with Planck scale physics. A generalisation of Fourier or wave-particle duality on curved spaces emerges. Another feature is the need for particles with fractional or braid statistics. The conformal group also has a special

D. Zilbersher, M. Gedalin

We study the pickup ion dynamics and mechanism of multiple reflection and acceleration at the structured quasi-perpendicular supercritical shock. The motion of the pickup ions in the shock is studied analytically and numerically using the test particle analysis in the model shock front. The analysis shows that slow pickup ions may be accelerated at the shock

Gábor Etesi

A systematical description of possible symmetry breakings in the SO(3) gauge theory and an algorithmical method to construct SU(2) or SO(3) invariant Higgs potentials in an arbitrary irreducible representation is given. We close our paper with the explicit construction of the Lagrangian of the simplest SO(3) theory violated to its subgroup A_4.

J. Balog, L. Fehér, L. Palla

The classification of the coadjoint orbits of the Virasoro algebra is reviewed and is then applied to analyze the so-called global Liouville equation. The review is self-contained, elementary and is tailor-made for the application. It is well-known that the Liouville equation for a smooth, real field $ϕ$ under periodic boundary condition is a reduction of th

Z. Bajnok

Defining the $WBC_n$ algebras as the commutant of certain screening charges a special form for the classical generators is obtained which does not change under quantisation. This enables us to give explicitly the first few generators in a compact form for arbitrary $WBC_n$ algebras.

Stefan Mashkevich

The claim put forward in [hep-th/9512051, hep-th/9612244] that the energies of the ``missing'' states of three anyons in a harmonic potential depend linearly on the statistics parameter, is incorrect because the wave functions proposed do not satisfy the anyonic interchange conditions.

T. P. Singh, Louis Witten

We study the spherical gravitational collapse of a compact object under the approximation that the radial pressure is identically zero, and the tangential pressure is related to the density by a linear equation of state. It turns out that the Einstein equations can be reduced to the solution of an integral for the evolution of the area radius. We show that f

Motoyuki Saijo, Hisa-aki Shinkai, Kei-ichi Maeda

Analyzing test particles falling into a Kerr black hole, we study gravitational waves in Brans-Dicke theory of gravity. First we consider a test particle plunging with a constant azimuthal angle into a rotating black hole and calculate the waveform and emitted energy of both scalar and tensor modes of gravitational radiation. We find that the waveform as wel

S. Wermter, V. Weber

Previous approaches of analyzing spontaneously spoken language often have been based on encoding syntactic and semantic knowledge manually and symbolically. While there has been some progress using statistical or connectionist language models, many current spoken- language systems still use a relatively brittle, hand-coded symbolic grammar or symbolic semant

D. R. Wilson, T. R. Martinez

Instance-based learning techniques typically handle continuous and linear input values well, but often do not handle nominal input attributes appropriately. The Value Difference Metric (VDM) was designed to find reasonable distance values between nominal attribute values, but it largely ignores continuous attributes, requiring discretization to map continuou

C. De Dominicis, I. Kondor, T. Temesvari

The state of art in spin glass field theory is reviewed.

Re'em Sari, Tsvi Piran

We show that external shocks cannot produce a variable GRB, unless they are produced by an extremely narrow jets (angular opening of < ~10^{-4}) or if only a small fraction of the shell emits the radiation and the process is very inefficient. Internal shocks can produce the observed complex temporal structure provided that the source itself is variable. In t

Stefanie Komossa, Hartmut Schulz

We present multi-component photoionization models allowing for local density inhomogeneities in the NLR to interpret the emission line spectra of Seyfert 2 galaxies. This approach leads to a successful match of a large set of line intensities from the UV to the NIR. In particular, the hitherto elusive NIR features [SIII]9062+9531 as well as high-ionization l