August 1993 arXiv papers — page 4

A. Brignole, L. E. Ibáñez, C. Muñoz

We perform a systematic analysis of the soft supersymmetry-breaking terms arising from four-dimensional strings. The analysis does not assume any specific supersymmetry-breaking mechanism but provides a means of parametrizing our ignorance in a way consistent with some known properties of four-dimensional strings. We introduce a {\it goldstino angle} paramet

Debashis Ghoshal, Porus Lakdawala, Sunil Mukhi

We discuss the effect of perturbations on the ground rings of $c=1$ string theory at the various compactification radii defining the $A_N$ points of the moduli space. We argue that perturbations by plus-type moduli define ground varieties which are equivalent to the unperturbed ones under redefinitions of the coordinates and hence cannot smoothen the singula

Nigel J. Kalton, Dirk Werner

Let $1<p,\,q<\infty$. It is shown for complex scalars that there are no nontrivial $M$-ideals in $L(L_p[0,1])$ if $p\neq 2$, and $K(\ell_p(\ell_q^n)$ is the only nontrivial $M$-ideal in $L(\ell_p(\ell_q^n)$. This proves a conjecture of C.-M. Cho and W. B. Johnson.

E. E. Donets, D. V. Gal&#39;tsov, M. S. Volkov

An infinite family of cornucopions is found within the $SU(2)\times U(1)$ sector of the 4--d heterotic string low-energy theory, the extremal $U(1)$ magnetic dilatonic black hole being the lowest energy state. Non-abelian cornucopions are interpreted as sphalerons associated with potential barriers separating topologically distinct Yang-Mills vacua on the $U

A. Dettki, I. Sachs, A. Wipf

We analyse the interacting theory of charged fermions, scalars, pseuso-scalars and photons propagating in 2-dimensional curved spacetime in detail. For certain values of the coupling constants the theory reduces to the gauged Thirring model and for others the Schwinger model incurved spacetime. It is shown that the interaction of the fermions with the pseudo

Gabriel Lopes Cardoso, Burt A. Ovrut

We present a manifestly supersymmetric procedure for calculating the contributions from matter loops to the mixed Kähler-gauge and to the mixed Kähler- Lorentz anomalies in $N=1, D=4$ supergravity-matter systems. We show how this procedure leads to the well-known result for the mixed Kähler-gauge anomaly. For general supergravity-matter systems the mixed Käh

Hisashi Yamamoto

We study the long-distance relevance of vortices (instantons) in an $N$-component axially U(1)-gauged four-Fermi theory in $1+1$ dimensions, in which a naive use of $1/N$ expansion predicts the dynamical Higgs phenomenon. Its general effective lagrangian is found to be a frozen U(1) Higgs model with the gauge-field mass term proportional to an anomaly parame

R. Endo

By introducing two kinds of gaugeon fields, we extend Yokoyama&#39;s Type I gaugeon formalism for quantum electrodynamics. The theory admits a q-number gauge transformation by which we can shift the gauge parameter into arbitrary numerical value; whereas in the original theory we cannot change the sign of the parameter. The relation to the Type II theory is

D. J. Broadhurst, A. L. Kataev

We have discovered 7 intimate connections between the published results for the radiative corrections, $\Ck$, to the Gross--Llewellyn Smith (GLS) sum rule, in deep-inelastic lepton scattering, and the radiative corrections, $\Cr$, to the Adler function of the flavour-singlet vector current, in $\ee$ annihilation. These include a surprising relation between t

J. Baacke, V. Kiselev

We present an evaluation of the 1-loop prefactor in the lifetime of a metastable state which decays at finite temperature by bubble nucleation. Such a state is considered in one-component phi^4 model in three space dimensions. The calculation serves as a prototype application of a fast numerical method for evaluating the functional determinants that appear i

G. Buchalla, A. J. Buras

We analyze the branching ratio for the FCNC mode $K^+\toπ^+ν\barν$\ in the standard model with QCD effects taken into account consistently to next-to-leading order. This involves a two-loop renormalization group analysis for the charm contribution, presented in this paper, and the calculation of $O(α_s)$ corrections to all orders in $m_t/M_W$ for the top-qua

K. Enqvist, P. Olesen

We consider Vachaspati&#39;s primordial magnetic field which is generated at the electroweak phase transition. Assuming that either the gradients of the Higgs field or, alternatively, the magnetic field itself are stochastic variables with a normal distribution, we find that the resulting magnetic field has an {\em rms} value in the present-day universe whic

D. A. Morris, A. Ringwald

We explore the discovery potential of cosmic ray physics experiments for Standard Model processes involving the nonperturbative production of O(30) weak gauge bosons. We demonstrate an experimental insensitivity to proton-induced processes and emphasize the importance of neutrino-induced processes. The Fly&#39;s Eye currently constrains the largest region of

M. Faber, O. Borisenko, S. Mashkevich, G. Zinovjev

Investigating the $Z_3$ symmetry in Quantum Chromodynamics (QCD) we show that full QCD with a vacuum of vanishing baryonic number does not lead to metastable phases. Rather in QCD with dynamical fermions, the degeneracy of $Z_3$ phases manifests itself in observables without open triality.

Lu YU, Zhao-bin SU, Yan-min LI

A brief review is presented on the studies of the hole motion in a two--dimensional quantum antiferromagnet. An extended introduction is given to cover the background of the problem. The quantum Bogoliubov--de Gennes formalism which treats the local distortion of the spin configuration and the quantum renormalization process on an equal footing, is outlined.

Gongwen Peng, Hans Herrmann

We study numerically the avalanches in a two--dimensional critical height sandpile model with sand grains added at the center of the system. Smaller avalanches near the center of the system are isotropic. Larger avalanches are, however, affected by the boundary of the system, to a degree that increases with the avalanche size. Up to linear system size $L=100

Ping Ao

We present a dynamical theory which incorporates the electron-electron correlations and the effects of external magnetic fields for an electron escaping from a helium surface. Analytical expressions for the escape rate can be obtained in various limits. In particular, the tunneling rate with a parallel magnetic field is presented explicitly.

M. S. Turner

NASA&#39;s Cosmic Background Explorer (COBE) Satellite has recently made the most accurate measurement of the temperature of the Universe determining it to be $2.726\pm 0.01\,$K. In trying to understand why the temperature has this value, one is led to discover the most fundamental features of the Universe---an early, radiation-dominated epoch, enormous entr

Anthony J. Bracken, Mark D. Gould, Yao-Zhong Zhang

The recently obtained results in \cite{ZG2} are used to compute the explicitly spectral-dependent $R$-matrix (or the intertwiners) on $V_{(6)}(x)\otimes V_{(6)}(y)$ and $V_{(3)}(x)\otimes V_{(6)}(y)$, where $V_{(6)}$ and $V_{(3)}$ are the 6-dimensional and fundamental representations of $U_q(A_2)$, respectively. It appears that the $R$-matrix on $V_{(3)}(x)\

Scott Hayward, Martin Sevior, Nathan Weiss, Dennis Wright

The proposed KAON factory at the Triumf Laboratory in Vancouver, Canada provides a unique opportunity for high statistics long baseline neutrino oscillation experiments. Several possibilities are under active consideration. In this paper we describe the theoretical expectations for a {\it very} long baseline experiment in which the neutrinos are directed tow

Tim R. Morris

We investigate the structure of Polchinski&#39;s formulation of the flow equations for the continuum Wilson effective action. Reinterpretations in terms of I.R. cutoff greens functions are given. A promising non-perturbative approximation scheme is derived by carefully taking the sharp cutoff limit and expanding in `irrelevancy&#39; of operators. We illustra

Jakub Rembielinski, Waclaw Tybor

Quantum Poincaré-Weyl group in two dimensional quantum Minkowski space-time is considered and an appriopriate relativistic kinematics is investigated. It is claimed that a consistent approach to the above questions demands a kind of a ``quantum geometry&#39;&#39; in the $q$-deformed space-time.

M. V. Sadovskii

We present a review of theoretical and experimental works on the problem of mutual interplay of Anderson localization and superconductivity in strongly disordered systems. We start with brief discussion of modern aspects of localization theory including the basic concept of scaling, self-consistent theory and interaction effects. After that we analyze disord

Xiangdong Ji, Peter Unrau

We study the $Q^2$ variation of the first moment of the nucleon&#39;s spin-dependent structure function $G_1$. As $Q^2 \rightarrow 0$ the moment is determined by the low energy theorem for Compton scattering. In the deep-inelastic region the moment is calculated using twist expansion to order $1/Q^2$. Based on these limits, we construct a formula which smoot

G. Q. Li, R. Machleidt, R. Fritz, H. Müther

We study elastic proton-nucleus scattering at intermediate energies. The nucleon-nucleus optical potential is derived from the Bonn nucleon-nucleon potential and the Dirac-Brueckner approach for nuclear matter. Our calculations, which do not contain any adjustable parameters, yield good agreement with experiment.

T. Nakatsukasa, K. Matsuyanagi, I. Hamamoto, W. Nazarewicz

Low-energy intrinsic $K^π$=1$^+$, $0^-$, $1^-$, $2^-$, and $3^-$ states in the even-even proton-rich Sr, Kr, and Zr nuclei are investigated using the quasiparticle random phase approximation. In the Z$\simeq$N nuclei the lowest-lying 1$^+$ states are found to carry unusually large $B(M1)$ strength. It is demonstrated that, unlike in the heavier nuclei, the o

W. G. Unruh

Using a simple version of the model for the quantum measurement of a two level system, the contention of Aharonov, Anandan, and Vaidman that one must in certain circumstances give the wavefunction an ontological as well as an epistemological significance is examined. I decide that their argument that the wave function of a system can be measured on a single

E. K. Sklyanin

For the integrable $N$-particle Calogero-Moser system with elliptic potential it is shown that the Lax operator found by Krichever possesses a classical $r$-matrix structure. The $r$-matrix is a natural generalisation of the matrix found recently by Avan and Talon (hep-th/9210128) for the trigonometric potential. The $r$-matrix depends on the spectral parame

Kordian Andrzej Smolinski

An example of a toy model of $D=2$ Minkowski space and Poincaré group with real deformation parameter $q$ is considered. A notion of free motion is defined. The kinematics and phase-space are constructed and the ``uncertainity&#39;&#39; ralations are found.

G. Mussardo, P. Simonetti

The short distance behaviour of massive integrable quantum field theories is analyzed in terms of the form factor approach. We show that the on-shell dynamics is compatible with different definitions of the stress-energy tensor $T_{μν}(x)$ of the theory. In terms of form factors, this is equivalent to having a possible non-zero matrix element $F_1$ of the tr

Sun Myong Kim, Thomas F. Walsh

The photon structure function is a useful testing ground for QCD. It is perturbatively computable apart from a contribution from what is usually called the hadronic component of the photon. There have been many proposals for this nonperturbative part of the real photon structure function. By studying moments of the virtual photon structure function, we explo

J. Lopez, D. Nanopoulos, G. Park, A. Zichichi

We consider a class of well motivated string-inspired flipped $SU(5)$ supergravity models which include four supersymmetry breaking scenarios: no-scale, strict no-scale, dilaton, and special dilaton, such that only three parameters are needed to describe all new phenomena $(m_t,\tanβ,m_{\tilde g})$. We show that the LEP precise measurements of the electrowea

P. Colangelo, C. A. Dominguez, G. Nardulli, N. Paver

We evaluate the branching ratios of the radiative decays $B \to K^* γ$, and $B \to K_1 γ$ in the framework of three-point function QCD sum rules. We find: $ Γ(B \to K^* γ) / Γ(b \to s γ) = 0.17 \pm 0.05$ and $ Γ(B \to K_1 γ) / Γ(b \to s γ) = 0.30 \pm 0.15$. We also study, in the infinite quark mass limit, the connection between the form factor of the radiati

G. Oliveira-Neto

A calculation of the no-boundary wave-function of the universe is put forward for a spacetime with negative curvature. A semi-classical Robertson-Walker approximation is attempted and two solutions to the field equations, one Lorentzian and the other a tunneling one are found. The regularity of those solutions are analysed explicitly, both in 2+1 and 3+1 dim

A. Carlini, J. Greensite

We expand on the idea that spacetime signature should be treated as a dynamical degree of freedom in quantum field theory. It has been argued that the probability distribution for signature, induced by massless free fields, is peaked at the Lorentzian value uniquely in D=4 dimensions. This argument is reviewed, and certain consistency constraints on the gene

C. C. A. Guenther, Per Arne Rikvold, M. A. Novotny

We apply a generalized numerical transfer-matrix method to the 2-d Ising ferro- magnet in a nonzero field to obtain complex constrained free energies. Below $T_c$ certain eigenstates of the transfer matrix are identified as representing a metastable phase. The imaginary parts of the metastable constrained free energies are found to agree with a field-theoret

T. Jungwirth, L. Smrcka

The capacitance of a double-heterojunction structure with a wide GaAs undoped layer embedded between two selectively doped AlGaAs barriers is calculated self-consistently as a function of intensity of the in-plane magnetic field. With increasing field intensity the capacitance initially increases and after reaching a maximum decreases toward a high field lim

Per Dahlqvist

We consider the spectrum of the evolution operator for bound chaotic systems by evaluating its trace. This trace is known to approach unity as $t \rightarrow \infty$ for bound systems. It is written as the Fourier transform of the logaritmic derivative of a zeta function whose zeros are identified with the eigenvalues of the operator. Zeta functions are expe

Y. P. Jing, H. J. Mo, G. Boerner, L. Z. Fang

Using numerical simulations, we investigate the large-scale gravitational clustering in a flat universe dominated by cold plus hot dark matter (i.e., $Ω_0=\ocdm+\ohdm+\obaryon=1$). Primordial density fluctuation spectrum is taken to have the Zel&#39;dovich-Harrison form. Three models are studied, with Model I having $\ocdm=0.69$, $\obaryon=0.01$, and $\ohdm=

E. T. Vishniac

Recent work on the transport of angular momentum in accretion disks suggests that the Velikhov-Chandrasekhar instability, in which a large scale magnetic field generates small scale eddys in a shearing environment, may be ultimately responsible for this process. Although there is considerable controversy about the origin and maintenance of this field in accr

M. Temple-Raston

On an oriented, compact, connected, real four-dimensional manifold, $M$, we introduce a topological Lagrangian gauge field theory with a Bogomol&#39;nyi structure that leads to non-singular, finite-Action, stable solutions to the variational field equations. These soliton-like solutions are analogous to the instanton in Yang-Mills theory. Unlike Yang-Mills i

B. L. Hu, Yuhong Zhang

We use the quantum Brownian model to derive the uncertainty relation for a quantum open system in an arbitrarily-squeezed initial state interacting with an environment at finite temperature. We examine the relative importance of the quantum and thermal fluctuations in the evolution of the system towards equilibrium with the aim of clarifying the meaning of q

Ulrich Ellwanger

We discuss the exact renormalization group or flow equation for the effective action and its decomposition into one particle irreducible N point functions. With the help of a truncated flow equation for the four point function we study the bound state problem for scalar fields. A combination of analytic and numerical methods is proposed, which is applied to

Thomas Mannel

Inclusive semileptonic decays are discussed in the framework of heavy quark effective field theory by employing the short distance expansion in the effective theory. The lowest order term turns out to be the parton model; the higher order terms may be regarded as correction terms to the parton model result. The first nonvanishing corrections to the parton mo

T-Y. Saito, I. R. Afnan

By calculating the contribution of the $π-π$ three-body force to the three-nucleon binding energy in terms of the $πN$ amplitude using perturbation theory, we are able to determine the contribution of the different $πN$ partial waves to the three-nucleon force. The division of the $πN$ amplitude into a pole and nonpole gives a unique procedure for the determ

C. Besliu, V. Popa, L. Popa, V. Topor Pop

Some odd characteristics are observed in the single particle distributions obtained from $ He + Li $ interactions at $ 4.5 AGeV/c $ momenta which are explained as the manifestation of a new mechanism of strangeness production via dibaryonic de-excitations. A signature of the formation of hadronic and baryonic clusters is also reported. The di-pionic signals

Erick J. Weinberg

Eigenfunctions of total angular momentum for a charged vector field interacting with a magnetic monopole are constructed and their properties studied. In general, these eigenfunctions can be obtained by applying vector operators to the monopole spherical harmonics in a manner similar to that often used for the construction of the ordinary vector spherical ha

Yas-Hiro Quano

We show that correlation functions of the $\bz _n $-Baxter model in the principal regime satisfy a system of difference equations. We obtain the spontaneous polarization of the $\bz _n $-Baxter model as a solution of the simplest difference equation.

Gregory Moore

This is a summary of a talk based on hep-th/9305139 and presented at the SUSY-93 International Workshop. We study infinite dimensional unbroken gauge symmetries which arise when time is toroidally compactified in string theory.

E. L. Berger, K. Sridhar

We compute the J/psi+gamma invariant-mass distributions from the QCD subprocess g + g --> J/psi+gamma. At large masses, this subprocess is the dominant mechanism for J/psi+gamma production, and data could provide a good test of QCD. The mass distribution peaks at relatively small masses (3.4 - 4.0 GeV) and the subprocess could, therefore, represent a signifi

P. H. Damgaard, H. B. Nielsen, R. Sollacher

We present a general scheme for extracting effective degrees of freedom from an underlying fundamental Lagrangian, through a series of well-defined transformations in the functional integral of the cut-off theory. This is done by introducing collective fields in a gauge-symmetric manner. Through appropriate gauge fixings of this symmetry one can remove long-

Apostolos Pilaftsis

The general Lagrangian containing the couplings of the Higgs scalars to Majorana neutrinos is presented in the context of singlet Majoron models with intergenerational mixings. The analytical expressions for the coupling of the Majoron field to fermions are derived within these models. Astrophysical considerations imply severe restrictions on the parameters

Markus H. Thoma

The transport interaction rates of elastic scattering processes of thermal partons in the quark-gluon plasma are calculated beyond the leading logarithm approximation using the effective perturbation theory for QCD at finite temperatures developed by Braaten and Pisarski. The results for the ordinary and transport interaction rates obtained from the effectiv

Y. Levin, R. R. Volkas

A discrete symmetry between quarks and (generalized) leptons can exist in nature, and its spontaneous symmetry breaking scale can be as low as a few TeV. Such a discrete symmetry also has interesting implications for how electroweak symmetry is spontaneously broken, because the simplest version of the theory requires two electroweak Higgs doublets rather tha

M. --C. Chu, Marcello Lissia, J. W. Negele

The Skyrme effective field theory is tested by evaluating nucleon ground state matrix elements of the correlation functions for two flavor density operators and two pseudoscalar density operators in the Skyrme model and comparing them with results in quenched lattice QCD. The possiblility of using quenched lattice QCD to study higher-order terms in effective

Rajamani Narayanan, Herbert Neuberger

An expression for the lattice effective action induced by chiral fermions in any even dimensions in terms of an overlap of two states is shown to have promising properties in two dimensions: The correct abelian anomaly is reproduced and instantons are suppressed.

H. Chen, J. Sexton, A. Vaccarino, D. Weingarten

We evaluate the infinite volume, continuum limit of glueball masses in the valence (quenched) approximation to lattice QCD. For the lightest states with $J^{PC}$ of $0^{++}$ and $2^{++}$, we obtain $m_0 = 1340 \pm 160$ MeV and $m_2 = 1900 \pm 320$ MeV.

Richard Easther

We present a number of new, exact scalar field cosmologies where the potential consists of two or more exponential terms. Such potentials are motivated by supergravity or superstring models formulated in higher dimensional spacetimes that have been compactified to (3+1)-dimensions. We have found solutions in both curved and flat Robertson Walker spacetimes.

A. L. Cabrera, Erie Morales, L. Altamirano, P. Espinoza

Description of TDS system, easy to implement-low budget (5 fig. on request). System might be useful to determine oxygen in High Tc superconductors. Paper accepted in Revista Mexicana de Fisica.

H. Y. Kee, P. Fazekas

We study the ground state phase diagram of the pseudospin model introduced by Doniach to describe the essential physics of Kondo lattices. We use variational trial states which augment the usual mean field solution by incorporating various intersite correlations. A composite spin correlation describing the antiparallel alignment of fluctuating triplets is fo

G. Giuricin, F. Mardirossian, M. Mezzetti, M. Persic

We present an observational mass function ranging from galaxies to massive galaxy clusters, derived from direct dynamical mass estimates. Our mass function shows, in the low-mass range of galaxies and groups, a behaviour in agreement with that of standard CDM (n=-2), while in the high-mass range (clusters) our mass function is shallower (and thus contains mo

Javier Elizondo

Let X be an algebraic projective variety in {\bf P}^n. Denote by {\cal C}_λ the space of all effective cycles on X whose homology class is λ\in H_{2p} (X,{\bf Z}). It is easy to show that {\cal C}_λ is an algebraic projective variety. Let χ({\cal C}_λ be its Euler characteristic. Define the Euler series of X by E_{p} = \sum_{λ\in{C}} \, χ({\cal C}_λ λ \in \,

Edward Odell, Thomas Schlumprecht

We give examples of two Banach spaces. One Banach space has no spreading model which contains $\ell_p$ ($1\le p<\infty$) or $c_0$. The other space has an unconditional basis for which $\ell_p$ ($1\le p<\infty$) and $c_0$ are block finitely represented in all block bases.

J. Alfaro

We derive the loop equations for the one Hermitian matrix model in any dimension. These are a consequence of the Schwinger-Dyson equations of the model. Moreover we show that in leading order of large $N$ the loop equations form a closed set.

Branko Urošević

This is the second in a series of papers devoted to open string field theory in two dimensions. In this paper we aim to clarify the origin and the role of discrete physical states in the theory. To this end, we study interactions of discrete states and generic tachyons. In particular, we discuss at length four point amplitudes. We show that behavior of the c

N. Aizawa, H. -T. Sato

We discuss quantum deformation of the affine transformation group and its Lie algebra. It is shown that the quantum algebra has a non-cocommutative Hopf algebra structure, simple realizations and quantum tensor operators. The deformation of the group is achieved by using the adjoint representation. The elements of quantum matrix form a Hopf algebra. Furtherm

E. Elizalde

The vacuum energy density (Casimir energy) corresponding to a massless scalar quantum field living in different universes (mainly no-boundary ones), in several dimensions, is calculated. Hawking&#39;s zeta function regularization procedure supplemented with a very simple binomial expansion is shown to be a rigorous and well suited method for performing the a

Tatsuo Kobayashi

We study differential calculus on h-deformed bosonic and fermionic quantum space. It is shown that the fermionic quantum space involves a parafermionic variable as well as a classical fermionic one. Further we construct the classical $su(2)$ algebra on the fermionic quantum space and discuss a mapping between the classical $su(2)$ and the h-deformed $su(2)$

Prem P. Srivastava

Self-consistent Hamiltonian formulation of scalar theory on the null plane is constructed following Dirac method. The theory contains also {\it constraint equations}. They would give, if solved, to a nonlinear and nonlocal Hamiltonian. The constraints lead us in the continuum to a different description of spontaneous symmetry breaking since, the symmetry gen

A. Bochkarev

We find a relation between the semiclassical approximation of the temperature (Matsubara) 2-point correlator and the corresponding classical Green function in real time at finite temperature. The anharmonic oscillator at finite temperature is used to illustrate our statement, which is however of rather general origin.

Naoya Hata, Paul Langacker

We update the analysis of the MSW and general astrophysical solutions to the combined solar neutrino observations by including the GALLEX II result. We also show that our parametrized flux uncertainties are equivalent to the Monte-Carlo results of Bahcall and Ulrich.

Mirjam Cvetiič, Paul Langacker, Jiang Liu

We show that the associated production $pp\to W^{\prime}W$, and the rare decay $pp\to W&#39;\to \bar\ell\ell W$ are useful tests of $W&#39;$ couplings to fermions at future hadron colliders. For $M_{W&#39;}\sim (1 - 3)$ TeV they would allow a clean determination on whether the $W&#39;$ couples to $V-A$ or $V+A$ currents. As an illustration a model in which t

Wolfgang Bock, Jan Smit, Jeroen C. Vink

We investigate a proposal for the construction of models with chiral fermions on the lattice using staggered fermions. In this approach the gauge invariance is broken by the coupling of the staggered fermions to the gauge fields. Motivated by previous results in the non-gauge invariant massive Yang-Mills theory and certain gauge-fermion models we aim at a dy

N. Ishizuka, Y. Shizawa

Renormalization factors for bilinear and four-quark operators with the Kogut-Susskind fermion action are perturbatively calculated to one-loop order in the general covariant gauge. Results are presented both for gauge invariant and non-invariant operators. For four-quark operators the full renormalization matrix for a complete set of operators with two types

Dalia S. Goldwirth, Malcolm J. Perry, Tsvi Piran, Kip S. Thorne

We study the propagator of a non-relativistic, non-interacting particle in any non-relativistic ``time-machine&#39;&#39; spacetime of the type shown in Fig.~1: an external, flat spacetime in which two spatial regions, $V_-$ at time $t_-$ and $V_+$ at time $t_+$, are connected by two temporal wormholes, one leading from the past side of $V_-$ to t the future

Albert-Laszlo Barabasi

A number of recent experiments have showed that surfactants can modify the growth mode of an epitaxial film, suppressing islanding and promoting layer-by-layer growth. Here a set of coupled equations are introduced to describe the coupling between a growing interface and a thin surfactant layer deposited on the top of the nonequilibrium surface . The equatio

Mark A. Gunderson, Lars Gerhard Jensen

Boson stars consist of a system of self-gravitating scalar fields which form a macroscopic quantum state and are a possible dark matter candidate. In this paper, we address the existence of boson stars in Brans-Dicke gravity. We show that solutions to the equations of motion of a boson star in Brans-Dicke gravity exist for different values of the coupling co

Martin B. Einhorn

We comment on the theoretical uncertainties involved in estimating the hadronic effects on the light-by-light scattering contribution to the anomalous magnetic moment of the muon, especially based on the analysis and results of T. Kinoshita, B. Ni\v zić, and Y. Okamoto, Phys.\ Rev.\ D31, 2108 (1985). From the point of view of an effective field theory and ch

S. Dawson, G. Valencia

We consider the possibility of observing a parity violating but $CP$ conserving interaction in the symmetry breaking sector of the electroweak theory. We find that the best probe for such an interaction is a forward-backward asymmetry in $W^+W^-$ production from polarized $e^-_R e^+_L$ collisions. An observable asymmetry would be strong evidence against a cu

D. V. Ahluwalia

This essay argues that when measurement processes involve energies of the order of the Planck scale, the fundamental assumption of locality may no longer be a good approximation. Idealized position measurements of two distinguishable spin-$0$ particles are considered. The measurements alter the space-time metric in a fundamental manner governed by the commut

As. Abada, C. R. Allton, Ph. Boucaud, D. B. Carpenter

We present the results of a numerical calculation of semi-leptonic form factors relevant for heavy flavour meson decays into light mesons, at $\beta=6.4$ on a $24^3 \times 60$ lattice, using the Wilson action in the quenched approximation. We obtain $f^+_K(0)=0.65\pm 0.18$, $V(0)=0.95\pm 0.34$, $A_1(0)=0.63\pm 0.14 $ and $A_2(0)=0.45\pm 0.33 $. We also obtai

A. A. Tseytlin

String backgrounds associated with gauged $G/H$ WZNW models in general depend non-trivially on $\alpha'$. We note, however, that there exists a local covariant $\a'$-dependent field redefinition that relates the exact metric-dilaton background corresponding to the $SL(2,R)/U(1)$ model to its leading-order form ($D=2$ black hole). As a consequence, there exis

Kelly Jay Davis

In this article we formulate a `topological&#39; field theory by employing a generalization of the Duistermaat-Heckman Theorem to localize the path-integral of the `topological action&#39; C^2 , where C is a slight modification of the Zamolodchikov C-Function, over the space of all two-dimensional field theories to the fixed points of the renormalization gro

Gilles Pisier

In this paper, we study {\it operator spaces\/} in the sense of the theory developed recently by Blecher-Paulsen [BP] and Effros-Ruan [ER1]. By an operator space, we mean a closed subspace $E\subset B(H)$, with $H$ Hilbert. We will be mainly concerned here with the ``geometry&#39;&#39; of {\it finite dimensional\/} operator spaces. In the Banach space catego

Yutaka Hosotani

In a wide class of three-dimensional Abelian gauge theories with a bare Chern-Simons term, the Lorentz invariance is spontaneously broken by dynamical generation of a non-vanishing magnetic field. A detailed computation of an energy density of the true vacuum is given. The originally massive photon becomes massless, fulfilling the role of a Nambu-Goldstone b

Hoi-Kwong Lo, Kai-Ming Lee, John Preskill

The electric charge of a wormhole mouth and the magnetic flux ``linked&#39;&#39; by the wormhole are non-commuting observables, and so cannot be simultaneously diagonalized. We use this observation to resolve some puzzles in wormhole electrodynamics and chromodynamics. Specifically, we analyze the color electric field that results when a colored object trave

Bergfinnur Durhuus, Thordur Jonsson

We prove that unitary two-dimensional topological field theories are uniquely characterized by $n$ positive real numbers $λ_1,\ldots λ_n$ which can be regarded as the eigenvalues of a hermitean handle creation operator. The number $n$ is the dimension of the Hilbert space associated with the circle and the partition functions for closed surfaces have the for

Fiorenzo Bastianelli

I describe a new method for computing trace anomalies in quantum field theories which makes use of path-integrals for particles moving in curved spaces. After presenting the main ideas of the method, I discuss how it is connected to the first quantized approach of particle theory and to heat kernel techniques. (Talk given at Journees Relativistes &#39;93).

Rodolfo Cuerno

The eigenvalues of the Corner Transfer Matrix Hamiltonian associated to the elliptic $R$ matrix of the eight vertex free fermion model are computed in the anisotropic case for magnetic field smaller than the critical value. An argument based on generating functions is given, and the results are checked numerically. The spectrum consists of equally spaced lev

R. D. Peccei

After briefly remarking on alternatives for breaking the electroweak symmetry, I discuss the implication that recent precision experiments at LEP have for the symmetry breaking sector. The difficulties associated with generating fermion masses when the electroweak symmetry is broken dynamically are exposed and an alternative to the walking technicolor - exte

H. Arthur Weldon

As a preliminary step, the radiation produced by a classical charged current coupled to a quantized $A_μ$ is solved. To each order in $α$, all infrared divergences cancel between the virtual $γ$&#39;s and the real $γ$&#39;s absorbed from the plasma or emitted into the plasma. When all orders of perturbation theory are summed, the finite answer predicts a sup

Jan Govaerts

Hyperfine spectroscopy of positronium formed in the presence of a static magnetic field is considered. Generalising the situation hitherto developed in the literature, the magnetic field is not assumed to be parallel to the momentum of incoming polarised positrons, while the possibility of electron polarisation is also included in the analysis. The results a

Domenico Giulini

In canonical quantum gravity certain topological properties of 3-manifolds are of interest. This article gives an account of those properties which have so far received sufficient attention, especially those concerning the diffeomorphism groups of 3-manifolds. We give a summary of these properties and list some old and new results concerning them. The append

C. J. Isham

An extended analysis is made of the Gell-Mann and Hartle axioms for a generalised `histories&#39; approach to quantum theory. Emphasis is placed on finding equivalents of the lattice structure that is employed in standard quantum logic. Particular attention is given to `quasi-temporal&#39; theories in which the notion of time-evolution is less rigid than in

D. Guido, T. Isola, S. Scarlatti

The theory of non symmetric Dirichlet forms is generalized to the non abelian setting, also establishing the natural correspondences among Dirichlet forms, sub-Markovian semigroups and sub-Markovian resolvents within this context. Examples of non symmetric Dirichlet forms given by derivations on Hilbert algebras are studied.

S. Albeverio, D. Guido, A. Ponosov, S. Scarlatti

We give a necessary and sufficient condition on a positive compact operator $T$ for the existence of a singular trace (i.e. a trace vanishing on the finite rank operators) which takes a finite non-zero value on $T$. This generalizes previous results by Dixmier and Varga. We also give an explicit description of these traces and associated ergodic states on $\

E. Z. Kuchinskii, M. V. Sadovskii, M. A. Erkabaev

We consider the model of superconducting pairing with the energy gap function which is odd over $k-k_{F}$.\ In this case superconductivity is possible even in the presence of an arbitrarily large point-like repulsion between electrons,\ which is attractive for the theory of high-temperature superconductors.\ We discuss mainly a model pairing interaction for

S. Das Sarma, Dongzi Liu

We propose a scaling model for the universal longitudinal conductivity near the mobility edge for the integer quantum Hall liquid. We fit our model with available experimental data on exponentially activated conductance near the Landau level tails in the integer quantum Hall regime. We obtain quantitative agreement between our scaling model and the experimen

Dongzi Liu, S. Das Sarma

We study the Landau level localization and scaling properties of a disordered two-dimensional electron gas in the presence of a strong external magnetic field. The impurities are treated as random distributed scattering centers with parameterized potentials. Using a transfer matrix for a finite-width strip geometry, we calculate the localization length as a

R Mannella, P Grigolini, BJ West

Herein we develop a dynamical foundation for fractional Brownian Motion. A clear relation is established between the asymptotic behaviour of the correlation function and diffusion in a dynamical system. Then, assuming that scaling is applicable, we establish a connection between diffusion (either standard or anomalous) and the dynamical indicator known as th