August 1995 arXiv papers — page 3

Jonathan M. Evans, Timothy J. Hollowood

An account is given of a technique for testing the equivalence between an exact factorizable S-matrix and an asymptotically-free Lagrangian field theory in two space-time dimensions. The method provides a way of resolving CDD ambiguities in the S-matrix and it also allows for an exact determination of the physical mass in terms of the Lambda parameter of per

C. Ford, I. Sachs

We define a weak-strong coupling transformation based on the Legendre transformation of the effective action. In the case of $N\es 2$ supersymmetric Yang-Mills theory, this coincides with the duality transform on the low energy effective action considered by Seiberg and Witten. This Legendre transform interpretation of duality generalizes directly to the ful

N. A. Saulina, E. M. Terentjev, M. V. Terentiev

"GRAMA" is a Mathematica package for doing symbolic tensor computations and complicated algebraic manipulations in 10-dimensional (D=10) simple (N=1) supergravity. The main new ingredients of this package inside the general Mathematica environment are the computation of complicated products of Dirac matrices and the treatment of covariant derivatives

A. Pasquinucci, K. Roland

We consider how to normalize the scattering amplitudes of 4D heterotic superstrings in a Minkowski background. We fix the normalization of the vacuum amplitude (the string partition function) at each genus, and of every vertex operator describing a physical external string state in a way consistent with unitarity of the $S$-matrix. We also provide an explici

U. A. Wiedemann, N. P. Landsman

Recently, it has been observed that a certain class of classical theories with constraints can be quantized by a mathematical procedure known as Rieffel induction. After a short exposition of this idea, we apply the new quantization theory to the Stueckelberg-Kibble model. We explicitly construct the physical state space ${\cal H}_{phys}$, which carries a ma

Yuji Yamada

We obtain the Bethe Ansatz equations for the broken ${\bf Z}_{N}$-symmetric model by constructing a functional relation of the transfer matrix of $L$-operators. This model is an elliptic off-critical extension of the Fateev-Zamolodchikov model. We calculate the free energy of this model on the basis of the string hypothesis.

J. Alam, P. Roy, S. Sarkar, S. Raha

Within the framework of a dynamical and physically transparent model developed earlier, we study the time evolution of various quark flavours in the baryon-free region in ultrarelativistic heavy ion collisions. We show that even under optimistic conditions, the quark-gluon system fails to achieve chemical equilibrium.

V. N. Pervushin, V. V. Papoyan, G. A. Gogilidze A. M. Khvedelidze, Yu. G. Palii

The role of the time surface term in the ADM Hamiltonian formulation of general relativity is investigated. We show that the variable contained in the time surface term (the scale factor) plays the role of a time-like variable. The conjugated variable represents the energy density in the reduced phase space, where the Schrödinger like equation for a wave fun

L. T. Handoko, T. Morozumi

We study the effect of the FCNC on rare $B$ decays in the beyond standard model with vector like singlet quarks. It has been shown that $b \rightarrow s γ$ does not receive sizable contribution compared with that of the standard model while $b \rightarrow d γ$, $b \rightarrow s(d) l^+ l^-$, can be changed from the predictions of the standard model.

Michael D. Sokoloff, Daniel M. Kaplan

We review the physics goals of an ultrahigh-statistics charm experiment and place them in the broader context of the community's efforts to study the Standard Model and to search for physics beyond the Standard Model, and we point out some of the experimental difficulties which must be overcome if these goals are to be met.

J M Pons, L C Shepley

We describe in detail how to eliminate nonphysical degrees of freedom in the Lagrangian and Hamiltonian formulations of a constrained system. Two important and distinct steps in our method are the fixing of ambiguities in the dynamics and the determination of inequivalent initial data. The Lagrangian discussion is novel, and a proof is given that the final n

Yongmin Yu, Gerhard Müller

For special coupling ratios, the one-dimensional (1D) s=1/2 Heisenberg model with antiferromagnetic nearest and next-nearest neighbor interactions has a pure dimer ground state, and the 1D s=1 Heisenberg model with antiferromagnetic bilinear and biquadratic interactions has an exact valence-bond-solid ground state. The recursion method is used to calculate t

L. Frachebourg, P. L. Krapivsky

The kinetics of an irreversible catalytic reaction on substrate of arbitrary dimension is examined. In the limit of infinitesimal reaction rate (reaction-controlled limit), we solve the dimer-dimer surface reaction model (or voter model) exactly in arbitrary dimension $D$. The density of reactive interfaces is found to exhibit a power law decay for $D<2$ and

Claudio Castellano, Sharon C. Glotzer

We re-explore the kinetics of spinodal decomposition in off-critical polymer blends through numerical simulations of the Cahn-Hilliard equation with the Flory-Huggins-De Gennes free energy functional. Even in the absence of thermal noise, the solution of the discretized equation of motion shows coarsening in the late stages of spinodal decomposition without

W. Hübner, K. H. Bennemann

The spin-lattice relaxation time $τ_{SL}$ is a key quantity both for the dynamical response of ferromagnets excited by laser pulses and as the speed limit of magneto-optical recording. Extending the theory for the electron paramagnetic resonance of magnetic impurities to spin-lattice relaxation in ferromagnetic rare earths we calculate $τ_{SL}$ for Gd and fi

V. De Rubeis, R. Hallgass, V. Loreto, G. Paladin

A model for fault dynamics consisting of two rough and rigid brownian profiles that slide one over the other is introduced. An earthquake occurs when there is an intersection between the two profiles. The energy release is proportional to the overlap interval. Our model exhibits some specific features which follow from the fractal geometry of the fault: (1)

Dirk van der Marel, Jae H. Kim

We propose a theoretical expression for the $k$- and $ω$-dependent dielectric function of a stack of two-dimensional layers coupled along the direction perpendicular to the layers, and discuss some of its properties. We argue that the plasma frequencies at $k=0$ should correspond to those which are experimentally obtained from optical measurements on {\em e.

G. Sinha, R. Chatterjee, M. Uehara, A. K. Majumdar

The time decay of the thermoremanent magnetization(TRM) of the $\mbox{Fe}_{80-\mbox{x}}\mbox{Ni}_{\mbox{x}}\mbox{Cr}_{20}$ ($14\leq \mbox{x} \leq 30$) alloys has been measured for four different magnetic phases within the fcc $\mbox{$γ$}$-phase using a SQUID magnetometer. In the spin-glass phase(SG)(X=19) very distinct ageing effects are observed where M(t)

R. Eder, Y. Ohta

Based on exact results for small clusters of 2D t-J model we demonstrate the existence of several distinct `channels&#39; in its inverse photoemission (IPES) spectrum. Hole-like quasiparticles can either be annihilated completely, or leave behind a variable number of spin excitations, which formed the `dressing cloud&#39; of the annihilated hole. In the phys

F. F. Assaad, M. Imada

We present a numerically stable Quantum Monte Carlo algorithm to calculate zero-temperature imaginary-time Green functions $ G(\vec{r}, τ) $ for Hubbard type models. We illustrate the efficiency of the algorithm by calculating the on-site Green function $ G(\vec{r}=0, τ) $ on $4 \times 4$ to $12 \times 12$ lattices for the two-dimensional half-filled repulsi

Tomotoshi Nishino

The density matrix renormalization group (DMRG) method is applied to the interaction round a face (IRF) model. When the transfer matrix is asymmetric, singular-value decomposition of the density matrix is required. A trial numerical calculation is performed on the square lattice Ising model, which is a special case of the IRF model.

Satoshi Fujimoto, Norio Kawakami

The finite-size spectrum for the multi-channel Kondo model is derived analytically from the exact solution, by mapping the nontrivial Z$_{n}$ part of the Kondo scattering into that for the RSOS model coupled with the impurity. The analysis is performed for the case of $n-2S=1$, where $n$ is the number of channel and $S$ is the impurity spin. The result obtai

R. Podgornik, H. H. Strey, K. Gawrisch, D. C. Rau

By equilibrating condensed DNA arrays against reservoirs of known osmotic stress and examining them with several structural probes, it has been possible to achieve a detailed thermodynamic and structural characterization of the change between two distinct regions on the liquid crystalline phase digram: a higher-density hexagonally packed region with long-ran

Dragan Huterer, Dimitar D. Sasselov, Paul L. Schechter

The primary distance indicators are established in our Galaxy and the Local Group. There are at least four different methods which give good distances: methods using proper motions, RR Lyraes, Cepheid variables, and Type II supernovae. However the data on independent distances is very fragmentary, due partly to nature and partly to technological limits. As a

T. Padmanabhan

The constraints on the models for the structure formation arising from various cosmological observations at different length scales are reviewed. The status of different models for structure formation is examined critically in the light of these observations.

Lutz V. Semig, Volker Mueller

Standard inflation with one scalar field produces primordial perturbations with a nearly flat (&#39;Harrison-Zeldovich&#39;) power spectrum. Here we consider first, a double inflation spectrum, and second, a massive scalar field with an interaction potential which mimics an early quartic interaction, but fading away at a characteristic scale. We solve numeri

J A Sellwood

I review the various mechanisms for creating bars in rotating stellar disks, and conclude that the swing-amplified feed-back loop, which produces rapidly tumbling bars, remains the most probable. The bar continues to evolve after its formation in a number of ways; here I discuss what appears to be inevitable thickening normal to the plane, continued spiral a

J. -P. Lasota, P. Haensel, M. A. Abramowicz

We show that for realistic equations of state of dense matter, the universal proportionality factor relating the maximum rotation rate of neutron stars due to mass-shedding limit to the mass and radius of maximum allowable mass configuration of non-rotating models results from a universal proportionality between masses and radii of static maximum-mass neutro

Pavel Kroupa

We investigate the hypothesis that stars form in aggregates of binary systems and that the dynamical evolution of these aggregates leads to the observed properties of binary stars in the Galactic field. We assume that the initial distribution of periods is flat in logP, where P is the orbital period in days, and 3<logP<7.5. We distribute 200 binaries in aggr

Ortwin Gerhard, James Binney

Axisymmetric density distributions are constructed which are invisible when viewed from a range of inclination angles $i$. By adding such distributions to a model galaxy, it can be made either disky or boxy without in any way affecting its projected image. As the inclination of a galaxy decreases from edge-on to face on, the range of `invisible&#39; densitie

James Binney, Ortwin Gerhard

An algorithm is developed and tested for the problem posed by photometric observations of the bulge of the Milky Way. The latter subtends a non-trivial solid angle on the sky, and we show that this permits inversion of the projected brightness distribution under the assumption that the bulge has three orthogonal mirror planes of specified orientation. A seri

Sean Keel, Shigefumi Mori

We show that if a flat group scheme acts properly, with finite stabilizers, on an algebraic space, then a quotient exists as a separated algebraic space. More generally we show any flat groupid for which the family of stabilizers is finite has a uniform geometric, uniform categorical quotient in the category of algebraic spaces. Our argument is elementary an

C. M. Newman, D. L. Stein

We provide rigorous proofs which show that the main features of the Parisi solution of the Sherrington-Kirkpatrick spin glass are not valid for more realistic spin glass models in any dimension and at any temperature.

Marco Frasca

We solve the higher order equations of the theory of the strong perturbations in quantum mechanics given in M. Frasca, Phys. Rev. A 45, 43 (1992), by assuming that, at the leading order, the wave function goes adiabatically. This is accomplished by deriving the unitary operator of adiabatic evolution for the leading order. In this way it is possible to show

Eric D&#39;Hoker, Darius Gagne

A systematic derivation is given of the worldline path integrals for the effective action of a multiplet of Dirac fermions interacting with general matrix-valued classical background scalar, pseudoscalar, and vector gauge fields. The first path integral involves worldline fermions with antiperiodic boundary conditions on the worldline loop and generates the

Alexander Kirillov

In this paper we study modular tensor categories (braided rigid balanced tensor categories with additional finiteness and non-degeneracy conditions), in particular, representations of quantum groups at roots of unity. We show that the action of modular group on certain spaces of morphisms in MTC is unitary with respect to the natural inner product on these s

V. L. Eletsky

Mass splitting between axial and vector $\bar{Q}q$ mesons is considered within the standard QCD sum rules. In agreement with the first experimental data on the $B_1$ meson ($J^P =1^{+}$) we find that the splitting for B is about the same as for D and show that $1/m_Q$ corrections to the meson masses are small.

M. Medina, J. A. Nieto

A relation between the MacDowell-Mansouri theory of gravity and the Pontrjagin toplogical invariant in $(3+1)$ dimensions is discussed. This relation may be of especial interest in the quest of finding a mechanism to go from non-dynamical to dynamical gravity.

Heinrich Röder, Joachim Stolze, Richard N. Silver, Gerhard Müller

The decay of (disorder-averaged) static spin correlation functions at T=0 for the one-dimensional spin-1/2 XXZ antiferromagnet with uniform longitudinal coupling $JΔ$ and random transverse coupling $Jλ_i$ is investigated by numerical calculations for ensembles of finite chains. At $Δ=0$ (XX model) the calculation is based on the Jordan-Wigner mapping to free

Martin Cederwall, Gabriele Ferretti, Bengt E. W. Nilsson, Per Salomonson

We derive, for $N\is2$ super-Yang--Mills with gauge group $SU(2)$ and massless matter, the supersymmetric quantum mechanical models describing the time evolution of multi-monopole configurations in the low energy approximation. This is a first step towards identifying the solitonic states mapped to fundamental excitations by duality in the model with four hy

S. Sitotaw, R. A. Serota

We extend our study of thermodynamics of a Kubo particle to temperatures smaller than the interlevel spacing. We obtain the distribution functions of spin susceptibility and heat capacity for Poisson and Wigner-Dyson level statistics. We evaluate the line shape of the Knight shift due to spin effects both in a single particle and for the ensemble average and

M. Yu. Konstantinov

The problem of topology change description in gravitation theory is analized in detailes. It is pointed out that in standard four-dimensional theories the topology of space may be considered as a particular case of boundary conditions (or constraints). Therefore, the possible changes of space topology in (3+1)-dimensions do not admit dynamical description no

D. A. Johnston, Ranasinghe P. K. C. Malmini

We investigate a generalized Ising action containing nearest neighbour, next to nearest neighbour and plaquette terms that has been suggested as a potential string worldsheet discretization on cubic lattices by Savvidy and Wegner. We use both mean field techniques and Monte-Carlo simulations to sketch out the phase diagram. The Gonihedric (Savvidy-Wegner) mo

C H Oh, K Singh

We consider the conditions under which the $q$-oscillator algebra becomes a Hopf $*$-algebra. In particular, we show that there are at least two real forms associated with the algebra. Furthermore, through the representations, it is shown that they are related to ${\text {su}}_{q^{1/2}}(2)$ with different conjugations.

Yoshiaki SOFUE

Analyzing the (l, b, Vlsr) data cube of 13CO(J=1-0) line emission obtained by Bally et al, we have investigated the molecular gas distribution and kinematics in the central +/-1 deg (150 pc) region of the Galaxy. We have applied the pressing method to remove the local- and foreground-gas components at low velocities in order to estimate the intensity more qu

Yukinori Yasui, Waichi Ogura

Symplectic geometry of the vortex filament in a curved three-manifold is investigated. There appears an infinite sequence of constants of motion in involution in the case of constant curvature. The Duistermaat-Heckman formula is examined perturbatively for the classical partition function in our model and verified up to the 3-loop order.

A. S. Hassan, M, Imachi, N

The two dimensional $CP^1$ model with $θ$ term is simulated. We compute the topological charge distribution $P(Q)$ by employing the ``set method&#34; and ``trial function method&#34;, which are effective in the calculations for very wide range of $Q$ and large volume. The distribution $P(Q)$ shows the Gaussian behavior in the small $β$ (inverse coupling cons

T. E. Browder, S. Pakvasa

We discuss the implications of CP violation as well as final state interaction phases in the experimental search for $D^0-\bar{D}^0$ mixing. At the present level of sensitivity, these are not yet a significant systematic experimental limitation.

Takaji Inamuro, Masato Yoshino, Fumimaru Ogino

A non-slip boundary condition at a wall for the lattice Boltzmann method is presented. In the present method unknown distribution functions at the wall are assumed to be an equilibrium distribution function with a counter slip velocity which is determined so that fluid velocity at the wall is equal to the wall velocity. Poiseuille flow and Couette flow are c

Steven Spencer, Henrik Jeldoft Jensen

The threshold for creep in the Bean critical state is investigated. We perturb the Bean state by an energy $Δε$. We find that no matter how small $Δε$ is it will always be able to induce creep somewhere on the Bean profile. This finding has important consequences for the interpretation of low temperature creep phenomena in terms of quantum creep.

Robert Bluhm, Alan Kostelecky

It is known that, after formation, a Rydberg wave packet undergoes a series of collapses and revivals within a time period called the revival time, $t_{\rm rev}$, at the end of which it is close to its original shape. We study the behavior of Rydberg wave packets on time scales much greater than $t_{\rm rev}$. We show that after a few revival cycles the wave

Todd A. Brun

Quantum chaos---the study of quantized nonintegrable Hamiltonian systems---is an extremely well-developed and sophisticated field. By contrast, very little work has been done in looking at quantum versions of systems which classically exhibit {\it dissipative} chaos. Using the decoherence formalism of Gell-Mann and Hartle, I find a quantum mechanical analog

I. C. Percival

Nondifferentiable fluctuations in space-time on a Planck scale introduce stochastic terms into the equations for quantum states, resulting in a proposed new foundation for an existing alternative quantum theory, primary state diffusion (PSD). Planck-scale stochastic space-time structure results in quantum fluctuations, whilst larger-scale curvature is respon

H. Garland, I. Grojnowski

In this paper we give a geometric construction of Cherednik&#39;s double affine Hecke algebra. We construct the algebra as the equivariant $K$-theory of the Lagrangian subvariety of the cotangent variety of the square of the flag variety of $G$, the variety being given by the union of the conormal bundles to the $G$-orbits on $\flag\times\flag$. This is a ge

Chongying Dong, Haisheng Li, Geoffrey Mason

A regular vertex operator algebra is a vertex operator algebra such that any weak module (without grading) is a direct sum of ordinary irreducible modules. In this paper we give several sufficient conditions under which a rational vertex operator algebra is regular. We prove that the moonshine module vertex operator algebra $V^{\natural},$ the vertex operato

M. Scheunert

The universal R-matrices and, dually, the coquasitriangular structures of the group Hopf algebra of a finite Abelian group (resp. of an arbitrary Abelian group) are determined. This is used to formulate graded multilinear algebra in terms of triangular or cotriangular Hopf algebras. For the convenience of the reader, in a separate section the definitions and

Mathias Pillin

Based on the vanishing of the second Hochschild cohomology group of the enveloping algebra of the Heisenberg algebra it is shown that differential algebras coming from quantum groups do not provide a non-trivial deformation of quantum mechanics. For the case of a q-oscillator there exists a deforming map to the classical algebra. It is shown that the differe

R. D. Amado, F. Cannata, J-P. Dedonder, M. P. Locher

We discuss pion multiplicities and single pion momentum spectra from proton antiproton annihilation at rest. Both the scaled phase space model and the Skyrme-coherent state approach describe these observables well. In the coherent state approach the puzzling size of the scale parameter relating the phase space integrals for different multiplicities is replac

C. J. Benesh, T. Goldman, G. J. Stephenson

Using a quark model, we calculate symmetry breaking effects in the valence quark distributions of the nucleon. In particular, we examine the breaking of the quark model SU(4) symmetry by color magnetic effects, and find that color magnetism provides an explanation for deviation of the ratio $d_V(x)/u_V(x)$ from $1/2$. Additionally, we calculate the effect of

Urs Achim Wiedemann, Pierre Scotto, Ulrich Heinz

The transverse momentum dependence of Hanbury-Brown/Twiss (HBT) interferometry radii for 2-body correlation functions provides experimental access to the collective dynamics in heavy-ion collisions. We present an analytical approximation scheme for these HBT radii which combines the recently derived model-independent expressions with an approximate determina

J. Goniakowski, J. M. Holender, L. N. Kantorovich, M. J. Gillan

First-principles calculations based on density functional theory and the pseudo\-potential method have been used to investigate the influence of gradient corrections to the standard LDA technique on the equilibrium structure and energetics of rutile TiO$_2$ and SnO$_2$ perfect crystals and their (110) surfaces. We find that gradient corrections increase the

J. Goniakowski, M. J. Gillan

First-principles calculations based on density functional theory and the pseudopotential method have been used to investigate the energetics of H$_2$O adsorption on the (110) surface of TiO$_2$ and SnO$_2$. Full relaxation of all atomic positions is performed on slab systems with periodic boundary conditions, and the cases of full and half coverage are studi

A. Valleriani

We show that the problem of Random Walk with boundary attractive potential may be mapped onto the free massive bosonic Quantum Field Theory with a line of defect. This mapping permits to recover the statistical properties of the Random Walks by using boundary $S$--matrix and Form Factor techniques.

T. A. Ivanova, A. D. Popov

Using the symmetry reductions of the self-dual Yang-Mills (SDYM) equations in (2+2) dimensions, we introduce new integrable equations which are nonautonomous versions of the chiral model in (2+1) dimensions, generalized nonlinear Schrodinger, Korteweg-de Vries, Toda lattice, Garnier and Euler-Arnold equations. The Lax pairs for all of these equations are der

Mauri Miettinen

Different regularizations are studied in localization of path integrals. We discuss the effect of the choice of regularization by evaluating the partition functions for the harmonic oscillator and the Weyl character for SU(2). In particular, we solve the Weyl shift problem that arises in path integral evaluation of the Weyl character by using the Atiyah-Pato

Chuan-Jie

The complete structure of the $WG_2$ algebra is obtained from an explicit realization by an abstract Virasoro algebra and a free boson field. We then construct its BRST operator and find a seven-parameter family of nilpotnt BRST operators. These free parameters are related to the canonical transformations of the ghost, antighost fields which leave the total

Chuan-Jie Zhu

By explicit calculation, I determine the structure of the ground ring of the critical $W_3$ gravity and show that there is an $su(3)$ invariant quadratic relation among the six basic elements. By using this result, I also construct some discrete physical states of the critical $W_3$ gravity.

L. Burakovsky, L. P. Horwitz, W. C. Schieve

We consider a relativistic strongly interacting Bose gas. The interaction is manifested in the off-shellness of the equilibrium distribution. The equation of state that we obtain for such a gas has the properties of a realistic equation of state of strongly interacting matter, i.e., at low temperature it agrees with the one suggested by Shuryak for hadronic

L. Burakovsky, L. P. Horwitz

We consider the relativistic statistical mechanics of an ensemble of $N$ events with motion in space-time parametrized by an invariant ``historical time&#39;&#39; $τ.$ We generalize the approach of Yang and Yao, based on the Wigner distribution functions and the Bogoliubov hypotheses, to find the approximate dynamical equation for the kinetic state of any no

L. Burakovsky, L. P. Horwitz, W. C. Schieve

We discuss the properties of an ideal relativistic gas of events possessing Bose-Einstein statistics. We find that the mass spectrum of such a system is bounded by $μ\leq m\leq 2M/μ_K,$ where $μ$ is the usual chemical potential, $M$ is an intrinsic dimensional scale parameter for the motion of an event in space-time, and $μ_K$ is an additional mass potential

L. Burakovsky, L. P. Horwitz

We consider 5D Kaluza-Klein type cosmological model with the fifth coordinate being a generalization of the invariant ``historical&#39;&#39; time $τ$ of the covariant theory of Horwitz and Piron. We distinguish between vacuum-, off-shell matter-, and on-shell matter-dominated eras as the solutions of the corresponding 5D gravitational field equations, and bu

L. Burakovsky, L. P. Horwitz

We discuss a cosmological Friedmann model modified by inclusion of off-shell matter which has an equation of state $p,ρ\propto T^5,$ $p=1/4ρ.$ Such matter is shown to have energy density comparable with that of non-interacting radiation at temperatures of the order of the Hagedorn temperature, $\sim 10^{12}$ K, indicating the possibility of a phase transitio

S. Sethi, M. Stern, E. Zaslow

We study the existence of monopole bound states saturating the BPS bound in N=2 supersymmetric Yang-Mills theories. We describe how the existence of such bound states relates to the topology of index bundles over the moduli space of BPS solutions. Using an $L^2$ index theorem, we prove the existence of certain BPS states predicted by Seiberg and Witten based

Sunao. Sakai

The nature of finite temperature transition in QCD is studied on a lattice with Wilson fermion. For massless quarks, the transition is smooth for two flavors, while it is of first order for three and six flavors. Form the study of transition in the case of non-degenerate as well as degenerate massive quark case,it is suggest that the finite temperature trans

Zheng Huang, Mahiko Suzuki

We obtain the general analytic solutions of the nonlinear $σ$-model in $3+1$ dimensions as the candidates for the disoriented chiral condensate (DCC). The nonuniformly isospin-orientated solutions are shown to be related to the uniformly oriented ones through the chiral (axial) rotations. We discuss the pion charge distribution arising from these solutions.

Charles A. Nelson, Minseob Kim, Daryl P. Nazareth, Hui-Chun Yang

The most general Lorentz invariant spin-correlation functions for $τ^{-}\rightarrow ρ^{-}ν,a_1^{-}ν,K^{*-}ν, π^{-}ν,K^{-}ν$ are expressed in terms of eight semi-leptonic parameters. They are physically defined in terms of tau-decay partial-width-intensities for polarized-final-states. The parameters are also expressed in terms of a ``$(V-A)\ +\ $additional c

Charles A. Nelson

The Lorentz structure of the tau lepton&#39;s charged-current can almost be completely determined by use of stage-two spin-correlation functions for the $\{ρ^{-},ρ^{+}\}$and $\{a_1^{-},a_1^{+}\}$ decay modes. It is possible to test for a ``$(V-A)$ $ + $ something&#39;&#39; structure in the ${J^{Charged}}_{Lepton}$ current, so as to bound the scales $Λ$ for `

Manuel Masip, Andrija Rasin

We consider supersymmetric extensions of the standard model with two pairs of Higgs doublets. We study the possibility of spontaneous $CP$ violation in these scenarios and present a model where the origin of $CP$ violation is soft, with all the complex phases in the Lagrangian derived from complex masses and vacuum expectation values (VEVs) of the Higgs fiel

Zhenjun Xiao, Xuelei Wang

In this report we present a review of recent developments in the TC/ETC theories, concentrating on the theoretical estimations and the phenomenological analysis about the Non-Oblique corrections on the $Zb\overline{b}$ vertex from ETC dynamics and Pseudo-Goldstone Bosons. The relevant studies about the vertex corrections on other processes from the PGBs were

Hung Jung Lu

We study the production of jet events containing large rapidity gaps in particle colliders due to the resolved photon mechanism. In particular, we analize these events at DESY HERA and future $e^+e^-$ linear colliders, including the possibility of $γγ$ laser backscattering beams. These events allow the study of the perturbative pomeron in environments comple

M. Asakawa, T. Hatsuda

Due to a rapid change of the entropy density $s(T)$ across the critical temperature $T_c$ of the QCD phase transition, the pressure $P(T)$ and the energy density $e(T)$ above $T_c$ generally deviate from their Stefan-Boltzmann values. We shall demonstrate this both analytically and numerically for a general class of $s(T)$ consistent with thermodynamical con

C. J. Fewster, A. Higuchi

We study real linear scalar field theory on two simple non-globally hyperbolic spacetimes containing closed timelike curves within the framework proposed by Kay for algebraic quantum field theory on non-globally hyperbolic spacetimes. In this context, a spacetime (M,g) is said to be `F-quantum compatible&#39; with a field theory if it admits a *-algebra of l

Oron Zachar, S. A. Kivelson, V. J. Emery

We find a solvable limit to the problem of the 1D electron gas interacting with a lattice of Kondo scattering centers. In this limit, we present exact results for the problems of incommensurate filling, commensurate filling, impurity vacancy states, and the commensurate-incommensurate transition.

H. -T. S. Lihn, E. -J. Choi, S. Kaplan, H. D. Drew

Spectral features induced by 45$^{\circ }$ in-plane misoriented grains have been observed in the far infrared magneto-transmission of YBa$_2$Cu$_3$O$% _{7-δ}$ thin films. Two strong dispersive features are found at 80 and 160 $cm^{-1}$ and a weaker one at 116 $cm^{-1}$. The data can be well represented by Lorentzian oscillator contributions to the conductivi

Ross H. McKenzie

The problem of deriving from microscopic theory a Ginzburg-Landau free energy functional to describe the Peierls or charge-density-wave transition in quasi-one-dimensional materials is considered. Particular attention is given to how the thermal lattice motion affects the electronic states. Near the transition temperature the thermal lattice motion produces

Franco Bagnoli

We study the damage spreading transition in a generic one-dimensional stochastic cellular automata with two inputs (Domany-Kinzel model) Using an original formalism for the description of the microscopic dynamics of the model, we are able to show analitically that the evolution of the damage between two systems driven by the same noise has the same structure

Tota Nakamura, Kenn Kubo

We clarify elementary excitations in the $Δ$-chain. They are found to be `kink&#39;-`antikink&#39; type domain wall excitations to the dimer singlet ground state. The characters of a kink and an antikink are quite different in this system: a kink has no excitation energy and is localized, while an antikink has a finite excitation energy and propagates. The e

Lam Hui, Edmund Bertschinger

We investigate three different local approximations for nonlinear gravitational instability in the framework of cosmological Lagrangian fluid dynamics of cold dust. They include the Zel&#39;dovich approximation (ZA), the ``non-magnetic&#39;&#39; approximation of Bertschinger \& Jain (1994, NMA), and a new ``local tidal&#39;&#39; approximation (LTA). The LTA

K. Bernlöhr

While atmospheric Cherenkov telescopes have a small field of view and a small duty fraction, arrays of particle detectors on ground have a 1\,sr field of view and a 100% duty fraction. On the other hand, particle detector arrays have a much higher energy threshold and an inferior hadron rejection as compared to Cherenkov telescopes. Low threshold particle de

S. V. H. Haugan

In gravitational lens systems with 3 or more resolved images of a quasar, the intrinsic variability may be unambiguously separated from the microlensing variability through parallax measurements from 3 observers when there is no relative motion of the lens masses (Refsdal 1993). In systems with fewer than 3 resolved images, however, this separation is not st

Yoshiaki Sofue

We investigate the three-dimensional structure of the so-called ``200-pc expanding molecular ring&#34; in the Galactic Center by analyzing (b, Vlsr) diagrams of the 13CO(J=1-0) line emission from the Bell-Telephone Laboratory survey. We show that the b-v features can be fitted by a spheroidal shell pinched at the equator (dumbbell-shaped shell), which we cal

S. V. H. Haugan

The contouring methods described by Lewis et al. (1993) and Witt (1993) are very efficient and elegant for obtaining the magnification of a point source moving along a straight track in the source plane. The method is, however, not very efficient for extended sources, because the amplification needs to be computed for numerous parallel tracks and then convol

J. Hwang

Fundamental formulae representing the density perturbation spectrums generated in inflationary scenarios are rigorously proved. Quantum fluctuations as initial conditions for structure generation in some inflationary era can be calculated in general scale. Thus, we could avoid the matching of the large and the small scale results at the horizon crossing epoc

T. S. Axelrod, R. A. Allsman, P. J. Quinn, D. P. Bennett

The MACHO experiment is searching for dark matter in the halo of the Galaxy by monitoring more than 20 million stars in the LMC and Galactic bulge for gravitational microlensing events. The hardware consists of a 50 inch telescope, a two-color 32 megapixel ccd camera, and a network of computers. On clear nights the system generates up to 8 GB of raw data and

Ziv Ran

We describe a method for counting maps of curves of given genus (and variable moduli) to $\Bbb P^2$, essentially by splitting the $\Bbb P^2$ in two; then specialising to the case of genus 0 we show that the method of quantum cohomology may be viewed as the &#39;mirror&#39; of the former method where one splits the $\Bbb P^1$ rather than the $\Bbb P^2$, and w

Peter Forgacs, Jozsef Gyurusi

A numerical study of static spherically symmetric monople solutions of a spontaneously broken SU(2) gauge theory coupled to a dilaton field is presented. Regular solutions seem to exist only up to a maximal value of the dilaton coupling. In addition to the generalization of the &#39;t Hooft-Polyakov monopole a discrete family of regular solutions is found, c

George Sterman

I discuss some of the basic techniques and results of soft gluon resummation, and their applications to scattering at collider energies.

B. Borasoy, Ulf-G. Meißner

We analyze the octet baryon masses and the pion--nucleon $σ$--term in the framework of heavy baryon chiral perturbation theory. In contrast to previous investigations, we include {\it all} terms up-to-and-including quadratic order in the light quark masses. The pertinent low--energy constants are fixed from resonance exchange. This leaves as the only free pa

Bastian Bergerhoff, Christof Wetterich

We discuss the electroweak phase-transition in the early universe, using non-perturbative flow equations for a computation of the free energy. For a scalar mass above $\sim 70$ GeV, high-temperature perturbation theory cannot describe this transition reliably. This is due to the dominance of three-dimensional physics at high temperatures which implies that t

Seungho Choe, Myung Ki Cheoun, Su Houng Lee

$g_{K N Λ}$ and $g_{K N Σ}$ are calculated using a QCD sum rule motivated method used by Reinders, Rubinstein and Yazaki to extract Hadron couplings to goldstone bosons. The SU(3) symmetry breaking effects are taken into account by including the contributions from the strange quark mass and assuming different values for the strange and the up down quark cond