arXiv papers from June 1992

Stanley Myint

Requirement that the vacuum expectation values of Higgs fields immediately after the phase transition be large enough imposes constraints upon the parameters of the minimal supersymmetric model. In particular, one obtains the upper bound on the lighter CP-even Higgs mass and the soft supersymmetry breaking scale for different values of the top quark mass.

Jeffrey E. Mandula

We report on a lattice QCD estimate of the quark spin fraction of the proton spin. The estimate is arrived at by means of a lattice QCD simulation of the polarized proton matrix element of the Adler-Bell-Jackiw anomaly. The preliminary result of the simulation is that this fraction is rather small. This is in accord with the interpretation of the EMC experim

Huazhong Zhang

We generalize our discussions and give more general physical applications of a new solution to the strong CP problem with magnetic monopoles as originally proposed by the author$^1$. Especially, we will discuss about the global topological structure in the relevant gauge orbit spaces to be clarified. As it is shown that in non-abelian gauge theories with a $

R. Shrock

We review some recent work on nonperturbative properties of fermions and connections with chiral gauge theories. In particular, we consider one of the ultimate goals of this program: the understanding of the actual fermion mass spectrum. It is pointed out that if quarks and leptons are composite, their masses may be set by the physics of the preons and their

G. Watts, R Weston

We present the results of a Monte--Carlo simulation of the $G_2^{(1)}$ Affine Toda field theory action in two dimensions. We measured the ratio of the masses of the two fundamental particles as a function of the coupling constant. Our results strongly support the conjectured duality with the $D_4^{(3)}$ theory, and are consistent with the mass formula of Del

Aleksandar Kocic, John Kogut, Simon Hands

Finite size scaling studies of monopole condensation in noncompact quenched lattice $QED$ indicate an authentic second order phase transition lying in the universality class of four dimensional percolation. Since the upper critical dimension of percolation is six, the measured critical indices are far from mean-field values. We propose a simple set of ratios

Swapna Mahapatra, Sudipta Mukherji, Anirvan M. Sengupta

We analyze the new states that have recently been discovered in 2D string theory by E. Witten and B. Zwiebach. Since the Liouville direction is uncompactified, we show that the deformations by the new ghost number two states generate equivalent classical solutions of the string fields. We argue that the new ghost number one states are responsible for generat

Toshiya Kawai, Taku Uchino, Sung-Kil Yang

In the first part of this paper we investigate the operator aspect of higher-rank supersymmetric model which is introduced as a Lie theoretic extension of the $N=2$ minimal model with the simplest case $su(2)$ corresponding to the $N=2$ minimal model. In particular we identify the analogs of chirality conditions and chiral ring. In the second part we constru

H. Zhang

A non-perturbative solution to strong CP problem is proposed. It is shown that the gauge orbit space with gauge potentials and gauge tranformations restricted on the space boundary in non-abelian gauge theories with a $\theta$ term has a magnetic monopole structure if there is a magnetic monopole in the ordinary space. The Dirac's quantization condition in t

Francois Gieres

We present explicit expressions for the Maurer-Cartan forms of the superdiffeomorphism group associated to a super Riemann surface. As an application to superconformal field theory, we use these forms to evaluate the effective action for the factorized superdiffeomorphism anomaly.

B. Grzadkowski, J. F. Gunion

We demonstrate that the ability to polarize the photons produced by back-scattering laser beams at a TeV scale linear $\epem$ collider could make it possible to determine whether or not a neutral Higgs boson produced in photon-photon collisions is a CP eigenstate. The relative utility of different types of polarization is discussed. Asymmetries that are only

E. Sezgin, K. S. Stelle

The nonlinear scalar-field realisation of $w_{1+\infty}$ symmetry in $d=2$ dimensions is studied in analogy to the nonlinear realisation of $d=4$ conformal symmetry $SO(4,2)$. The $w_{1+\infty}$ realisation is derived from a coset-space construction in which the divisor group is generated by the non-negative modes of the Virasoro algebra, with subsequent app

J. Bagger, S. Dawson, G. Valencia

We use chiral perturbation theory to show that pseudo-Goldstone boson scattering and gluon fusion probe different aspects of electroweak symmetry breaking at hadron colliders. In particular, the physics responsible for unitarizing the lowest-order pseudo-Goldstone boson scattering amplitudes need not significantly affect the gluon fusion process. We first sh

Meinulf Göckeler, Hans A. Kastrup, Thomas Neuhaus, Frank Zimmermann

We study the $O(4)$-symmetric $ \Phi^4 $-theory in the scaling region of the broken phase using the standard and a Symanzik improved action with infinite bare self-coupling $\lambda$. A high precision Monte Carlo simulation is performed by applying the reflection cluster algorithm. Employing the histogram method we analytically continue to a sequence of valu

Shyamoli Chaudhuri, Joseph D. Lykken

We analyse in detail the $SL(2,R)$ black hole by extending standard techniques of Kac-Moody current algebra to the non-compact case. We construct the elements of the ground ring and exhibit W-infinity type structure in the fusion algebra of the discrete states. As a consequence, we can identify some of the exactly marginal deformations of the black hole. We

M. Dubois-Violette, M. Henneaux, M. Talon, CM. Viallet

We produce the general solution of the Wess-Zumino consistency condition for gauge theories of the Yang-mills type, for any ghost number and form degree. We resolve the problem of the cohomological independence of these solutions. In other words we fully describe the local version of the cohomology of the BRS operator, modulo the differential on space--time.

Robert H. Brandenberger, Anne-Christine Davis

If stable electroweak strings are copiously produced during the electroweak phase transition, they may contribute significantly to the presently observed baryon to entropy ratio of the universe. This analysis establishes the feasibility of implementing an electroweak baryogenesis scenario without a first order phase transition.

Simon Hands, Aleksandar Kocic, John Kogut

The Four Fermi model with discrete chiral symmetry is studied in three dimensions at non-zero chemical potential and temperature using the Hybrid Monte Carlo algorithm. The number of fermion flavors is chosen large $(N_f=12)$ to compare with analytic results. A first order chiral symmetry restoring transition is found at zero temperature with a critical chem

Andrei Linde

Recent progress in the theory of the electroweak phase transition is discussed. For the Higgs boson mass smaller than the masses of W and Z bosons, the phase transition is of the first order. However, its strength is approximately 2/3 times less than what follows from the one-loop approximation. This rules out baryogenesis in the minimal version of the elect

M. -P. Lombardo, G. Parisi, A. Vladikas

We study the hadronic spectrum in quenched lattice QCD using an improved Wilson fermion action (Hamber-Wu(1983),Eguchi-Kawamoto(1984)) at $\beta= 5.7$ and $\beta =6.0$. We find a systematic reduction of the finite spacing effects compared to the results obtained by using the standard Wilson action.

Stephen P. Braham

We investigate the embedding variable approach to geometrodynamics advocated in work by Isham, Kucha\v{r} and Unruh for a general class of coordinate conditions that mirror the Isham-Kucha\v{r} Gaussian condition but allow for arbitrary algebraic complexity. We find that the same essential structure present in the ultralocal Gaussian condition is repeated in

Damien Pierce, Aris Papadopoulos

We consider radiative corrections to the decay rate $\Gamma(H\rightarrow ZZ)$ of the heavy {\it CP}-even Higgs boson of the minimal supersymmetric model to two $Z$ bosons. We perform a one loop Feynman diagram calculation in the on-mass-shell renormalization scheme, and include the third generation of quarks and squarks. The tree level rate is suppressed by

D. Coffey, S. A. Trugman

The antiferromagnetic Heisenberg Hamiltonian is investigated on a truncated tetrahedron, which is a closed 12 site system. We find that the ground state has many similarities to that of $C_{60}$. We study 2- and 4-spin correlations in the classical ground state of the truncated tetrahedron and calculate the same correlations in the exact S=1/2 ground state.

Steven Carlip

In Hawking's Euclidean path integral approach to quantum gravity, the partition function is computed by summing contributions from all possible topologies. The behavior such a sum can be estimated in three spacetime dimensions in the limit of small cosmological constant. The sum over topologies diverges for either sign of $\Lambda$, but for dramatically diff

D. C. Kennedy

In the canonical up-quark seesaw, the ratios of light neutrino masses are more easily predicted than the masses themselves. Under explicitly enumerated neccesary but minimal assumptions, these ratios are obtained, including radiative corrections. The predictions remain uncertain only by the top quark mass and triviality mass limit, and the power law of the s

D. Coffey, S. A. Trugman

The Heisenberg antiferromagnet, which arises from the large $U$ Hubbard model, is investigated on the $C_{60}$ molecule and other fullerenes. The connectivity of $C_{60}$ leads to an exotic classical ground state with nontrivial topology. We argue that there is no phase transition in the Hubbard model as a function of $U/t$, and thus the large $U$ solution i

R. Sekhar Chivukula, Mitchell Golden, Dimitrios Kominis, M. V. Ramana

We calculate the production rate of gauge-boson pairs at the SSC in a model with a ``hidden'' electroweak symmetry breaking sector. We show that the signal of electroweak symmetry breaking is lower than the background and that we cannot necessarily rely on gauge boson pairs as a signal of the dynamics of symmetry breaking.

Vipul Periwal

The flow of the action induced by changing $N$ is computed in large $N$ matrix models. It is shown that the change in the action is non-analytic. This non-analyticity appears at the origin of the space of matrices if the action is even.

E. Bergshoeff, E. Sezgin

Starting from the new minimal multiplet of supergravity in $2+2$ dimensions, we construct two types of self-dual supergravity theories. One of them involves a self-duality condition on the Riemann curvature and implies the equations of motion following from the Hilbert-Einstein type supergravity action. The other one involves a self-duality condition on a {\

S. G. Naculich, C. -P. Yuan

In a recent paper, Chivukula and Golden claimed that the electroweak symmetry--breaking sector could be hidden if there were many inelastic channels in the longitudinal $WW$ scattering process. They presented a model in which the $W$'s couple to pseudo--Goldstone bosons, which may be difficult to detect experimentally. Because of these inelastic channels, th

T. G. Rizzo

Once it is discovered, the determination of the various couplings of a new neutral gauge boson at a hadron supercollider will not be an easy task. We review several recent studies that have begun to examine this issue for both the SSC and LHC.

D. M. McAvity, H. Osborn

A framework allowing for perturbative calculations to be carried out for quantum field theories with arbitrary smoothly curved boundaries is described. It is based on an expansion of the heat kernel derived earlier for arbitrary mixed Dirichlet and Neumann boundary conditions. The method is applied to a general renormalisable scalar field theory in four dime

C. S. Aulakh, V. Soni

We generalize our results${}^1$ on charged topological solitons (CTS) in $4+1$ dimensional $SU(3)$ Yang-Mills-Chern-Simons (YMCS) theory to $SU(N)$. The $SU(N)$ multiplet structure of two classes of solitons associated with the maximal embeddings $SU(2)\times U(1)^{N-2}\subset SU(N)$ and $SO(3)\times U(1)^{N-3}\subset SU(N)$ and the vital role of the $SU(N)$

Peter E. Haagensen, Jose I. Latorre

We develop a coordinate space renormalization of massless Quantum Electrodynamics using the powerful method of differential renormalization. Bare one-loop amplitudes are finite at non-coincident external points, but do not accept a Fourier transform into momentum space. The method provides a systematic procedure to obtain one-loop renormalized amplitudes wit

M. H. Friedman, Y. N. Srivastava, A. Widom

The constraint imposed by Gauss' law is used to show that the matrix elements of n-point Wightman Functions of gluon field and quark current operators at different space time points vanish when taken between physical states.

S. G. Naculich, C. -P. Yuan

It has been argued that if light Higgs bosons do not exist then the self--interactions of $W$'s become strong in the TeV region and can be observed in longitudinal $WW$ scattering. We present a model with many inelastic channels in the $WW$ scattering process, corresponding to the creation of heavy fermion pairs. The presence of these heavy fermions affects

B. A. Berg, U. Hansmann, T. Neuhaus

To investigate order-order interfaces, we perform multimagnetical Monte Carlo simulations of the $2D$ and $3D$ Ising model. Following Binder we extract the interfacial free energy from the infinite volume limit of the magnetic probability density. Stringent tests of the numerical methods are performed by reproducing with high precision exact $2D$ results. In

D. Asner, R. B. Mann, J. L. Murison, T. G. Steele

Higher-loop corrections to the pseudoscalar ($0^{-+}$) gluonium correlation function will be used to obtain the leading gluon condensate contributions to the subtraction-independent QCD sum-rules. The effect of these higher-loop corrections on the sum-rule estimates of the pseudoscalar gluonium mass will be investigated. The final results of this analysis co

R. B. Mann

A classical two dimensional theory of gravity which has a number of interesting features (including a Newtonian limit, black holes and gravitational collapse) is quantized using conformal field theoretic techniques. The critical dimension depends upon Newton's constant, permitting models with $d=4$. The constraint algebra and scaling properties of the model

Zheng Huang, K. S. Viswanathan, D. D. Wu

We study the QCD vacuum orientation angles in correlation with the strong CP phases. A vacuum alignment equation of the dynamical chiral symmetry breaking is derived based on the anomalous Ward identity. It is emphasized that a chiral rotation of the quark field causes a change of the vacuum orientation and a change in the definition of the light pseudoscala

Zheng Huang, K. S. Viswanathan

We examine dynamical mass generation in QCD with large current mass quarks. A renormalization group analysis is performed to separate fermion self-mass into a dynamical and a kinematical part. It is shown that the energy scale og the Schwinger-Dyson (SD) equation and the effective gauge coupling are fixed by the current mass. The dynamical self-mass satisfie

J. Alfaro, P. H. Damgaard

We compute the critical exponents of $d = 1$ string theory to leading order, using the renormalization group approach recently suggested by Br\'{e}zin and Zinn-Justin.

Jan de Boer, Jacob Goeree

In this paper we study arbitrary $W$ algebras related to embeddings of $sl_2$ in a Lie algebra $g$. We give a simple formula for all $W$ transformations, which will enable us to construct the covariant action for general $W$ gravity. It turns out that this covariant action is nothing but a Fourier transform of the WZW action. The same general formula provide

F. De Jonghe, R. Siebelink, W. Troost, S. Vandoren

The Jacobian for infinitesimal BRST transformations of path integrals for pure Yang-Mills theory, viewed as a matrix $\unity +\Delta J$ in the space of Yang-Mills fields and (anti)ghosts, contains off-diagonal terms. Naively, the trace of $\Delta J$ vanishes, being proportional to the trace of the structure constants. However, the consistent regulator $\cR$,

G. Mikhalkin

The subject of this paper is the problem of arrangement of real algebraic curves on real algebraic surfaces. In this paper we extend Rokhlin, Kharlamov-Gudkov-Krakhnov and Kharlamov-Marin congruences for curves on surfaces and give some applications of this extension. For some pairs consisting of a surface and a curve on this surface (in particular for M-pai

Simon M. Catterall, John B. Kogut, Ray L. Renken

We present the results of a numerical simulation aimed at understanding the nature of the `c = 1 barrier' in two dimensional quantum gravity. We study multiple Ising models living on dynamical $\phi^3$ graphs and analyse the behaviour of moments of the graph loop distribution. We notice a universality at work as the average properties of typical graphs from

H. Aratyn, L. A. Ferreira, J. F. Gomes, A. H. Zimerman

A simple description of the KP hierarchy and its multi-hamiltonian structure is given in terms of two Bose currents. A deformation scheme connecting various W-infinity algebras and relation between two fundamental nonlinear structures are discussed. Properties of Fa\'a di Bruno polynomials are extensively explored in this construction. Applications of our me

Ian I Kogan, Gordon W Semenoff, Nathan Weiss

We show that a lattice model for induced lattice QCD which was recently proposed by Kazakov and Migdal has a $Z_N$ gauge symmetry which, in the strong coupling phase, results in a local confinement where only color singlets are allowed to propagate along links and all Wilson loops for non-singlets average to zero. We argue that, if this model is to give QCD

Terence Hwa

We study the nonequilibrium dynamics of line liquids as realized in the nonlinear motion of flux lines of a superconductor driven by an applied electric current. Our analysis suggests a transition in the dynamics of the lines from a smooth, laminar phase at small driving forces, to a rough, turbulent phase when the drive is increased. We explore the nature o

Stanley Deser, Roman Jackiw

To travel into the past, to observe it, perhaps to influence it and correct mistakes of one's youth, has been an abiding fantasy of mankind for as long as we have been aware of a past. Here are described some recent scientific investigations on this topic.

Roman Jackiw

Professor M. C. Polivanov and I met only a few times, during my infrequent visits to the-then Soviet Union in the 1970's and 1980's. His hospitality at the Moscow Steclov Institute made the trips a pleasure, while the scientific environment that he provided made them professionally valuable. But it is the human contact that I remember most vividly and shall

Roman Jackiw, So-Young Pi

These days, Franco Iachello is {\it the\/} eminent practitioner applying classical and finite groups to physics. In this he is following a tradition at Yale, established by the late Feza Gursey, and succeeding Gursey in the Gibbs chair; Gursey in turn, had Pauli as a mentor. Iachello's striking achievement has been to find an actual realization of arcane sup

H. Itoyama

The hierarchical nonlinear super-differential equations are identified which describe universal behavior of the discretized model of $2d$ supergravity recently proposed. This is done by first taking a double scaling limit of the super Virasoro constraints ( at finite $N$) of the model and by rederiving it from the $\tilde{G}_{-1/2}$ constraint and the two re

Gyan Bhanot, Michael Creutz, Jan Lacki

We compute the weak coupling expansion for the energy of the three dimensional Ising model through 48 excited bonds. We also compute the magnetization through 40 excited bonds. This was achieved via a recursive enumeration of states of fixed energy on a set of finite lattices. We use a linear combination of lattices with a generalization of helical boundary

P. Di Francesco, C. Itzykson, J. -B. Zuber

We obtain in closed form averages of polynomials, taken over hermitian matrices with the Gaussian measure involved in the Kontsevich integral, and prove a conjecture of Witten enabling one to express analogous averages with the full (cubic potential) measure, as derivatives of the partition function with respect to traces of inverse odd powers of the externa

G. P. Korchemsky

Macroscopic loop correlators are investigated in the hermitian one matrix model with the potential perturbed by the higher order curvature term. In the phase of smooth surfaces the model is equivalent to the minimal conformal matter coupled to gravity. The properties of the model in the intermediate phase are similar to that of the discretized bosonic string

R. Brandenberger, V. Mukhanov, T. Prokopec

We propose a general definition of nonequilibrium entropy of a classical stochastic field. As an example of particular interest in cosmology we apply this definition to compute the entropy of density perturbations in an inflationary Universe. On the scales of structures in the Universe, the entropy of density perturbations dominates over the statistical fluc

Kiwoon Choi

After discussing the intrinsic ambiguity in determining the light quark mass ratio $m_u/m_d$, we reexamine the recent proposal that this ambiguity can be resolved by applying the QCD multipole expansion for the heavy quarkonium decays. It is observed that, due to instanton effects, some matrix elements which have been ignored in previous works can give a sig

Shin'ichi Nojiri, Ichiro Oda

We consider Callan, Giddings, Harvey and Strominger's (CGHS) two dimensional dilatonic gravity with electromagnetic interactions. This model can be also solved classically. Among the solutions describing static black holes, there exist extremal solutions which have zero temperatures. In the extremal solutions, the space-time metric is not singular. We also o

Shin'ichi Nojiri

We propose random matrix models which have $N=\half$ supersymmetry in zero dimension. The supersymmetry breaks down spontaneously. It is shown that the double scaling limit can be defined in these models and the breakdown of the supersymmetry remains in the continuum limit. The exact non-trivial partition functions of the string theories corresponding to the

M. Srednicki

The free energy of the Penner model is shown to be closely related to the integral over the two diagonalizing unitary matrices of a complex rectangular matrix.

T. Han, G. Valencia, S. Willenbrock

We discuss weak-vector-boson scattering, at next-to-leading order in QCD, within the framework of hadronic structure functions. We use this approach to calculate the Higgs-boson production cross section via vector-boson fusion at the LHC/SSC; we find a modest increase over the leading-order prediction. We also give expressions for the distribution of vector

Jean-Pierre Ader, Francois Gieres, Yves Noirot

Starting from the Wess-Zumino action associated to the super Weyl anomaly, we determine the local counterterm which allows to pass from this anomaly to the chirally split superdiffeomorphism anomaly (as defined on a compact super Riemann surface without boundary). The counterterm involves the graded extension of the Verlinde functional and the results can be

Barton Zwiebach

The complete quantum theory of covariant closed strings is constructed in detail. The action is defined by elementary vertices satisfying recursion relations that give rise to Jacobi-like identities for an infinite chain of string field products. The genus zero string field algebra is the homotopy Lie algebra $L_\infty$, and the higher genus algebraic struct

Vandana Singh, Richard W. Haymaker, Dana A. Browne

We explore the analogy between quark confinement and the Meissner effect in superconductors. We measure the response of color-magnetic "supercurrents" from Dirac magnetic monopoles to the presence of a static quark-antiquark pair in four dimensional U(1) lattice gauge theory. Our results indicate that in the confined phase these currents screen the color-ele

J. A. Casas, F. Gómez, C. Muñoz

The capability of string theories to reproduce at low energy the observed pattern of quark and lepton masses and mixing angles is examined, focusing the attention on orbifold constructions, where the magnitude of Yukawa couplings depends on the values of the deformation parameters which describe the size and shape of the compactified space. A systematic expl

Greg W. Anderson

In the standard scenario, the electroweak phase transition is a first order phase transition which completes by the nucleation of critical bubbles. Recently, there has been speculation that the standard picture of the electroweak phase transition is incorrect. Instead, it has been proposed that throughout the phase transition appreciable amounts of both brok

Jyoti Agrawal, Paul H. Frampton, Daniel Ng

In an $e^- p$ collider, a striking signature for a dilepton gauge boson is \ep \ ; this cross-section is calculated by using the helicity amplitude technique. At HERA, with center-of-mass energy $\sqrt s = 314 GeV$, a dilepton mass above $150 GeV$ is inaccessible but at LEPII-LHC, with a center-of-mass energy $\sqrt s = 1790 GeV $, masses up to 650 GeV can b

Philippe Fischer, Douglas L. Welch, Mario Mateo

In this paper we investigate the internal dynamics of the LMC cluster NGC 1978 through the use of Photometric (CCD images) and kinematic (stellar radial velocities) data. We apply a variety of dynamical models to this data, including multi-mass King-Michie models and rotating and non-rotating oblate spheroid models. We discuss the cluster mass-to-light ratio

David E. Brahm

The Higgs contribution to the effective potential appears to be complex. How do we interpret this, and how should we modify the calculation to calculate physical quantities such as the critical bubble free energy?

A. Kocic, J. B. Kogut, M. -P. Lombardo, K. C. Wang

The interplay of spectroscopy, scaling laws and critical indices is studied in strongly coupled quenched QED. Interpreted as a model of technicolor having strong interactions at short distances, we predict the techni-meson mass spectrum in a simplified model of a dynamically generated top quark mass $M_f$. Our results support the strict inequality that the t

F. Pisano, V. Pleitez

We consider a gauge model based on $SU(3)\otimes U(1)$ symmetry in which the lepton number is violated explicitly by charged scalar and gauge bosons, including a vector field with double electric charge. Although there exist in the literature several models based on a $SU(3)\otimes U(1)$ gauge symmetry, our model has a different representation content and a

J. A. Dixon

Canonical forms are given for the nilpotent BRS operator $\d$ and the covariant `loop space' derivative ${\cal D}_{\m}$ for the p-brane fields for all odd p. The defining characteristic of ${\cal D}_{\m}$ is that it is a functional derivative operator which generalizes the ordinary functional derivative and also commutes with $\d$. Methods of construction fo

Jing-Dong Wang, Carleton DeTar

The three-dimensional, three-state Potts model is studied as a paradigm for high temperature quantum chromodynamics. In a high statistics numerical simulation using a Swendson-Wang algorithm, we study cubic lattices of dimension as large as $64^3$ and measure correlation functions on long lattices of dimension $20^2\times 120$ and $30^2\times 120$. These cor

Adam F. Falk, Michael Luke

We construct an effective Lagrangian describing the interaction of soft pions and kaons with mesons containing a heavy quark and light degrees of freedom in an orbital $p$ wave. The formalism is easily extended to heavy mesons and baryons in arbitrary excited states. We calculate the leading contributions to the strong decays $\dtwo\to\d\pi$, $\dtwo\to\dstar

Per Elmfors

A self-consistent renormalization scheme at finite temperature and zero momentum is used together with the finite temperature renormalization group to study the temperature dependence of the mass and the coupling to one-loop order in the $(\phi^3)_6$- and $(\phi^4)_4$-models. It is found that the critical temperature is shifted relative to the naive one-loop

Hikaru Kawai, Yoshihisa Kitazawa, Masao Ninomiya

We formulate quantum gravity in $2+\epsilon$ dimensions in such a way that the conformal mode is explicitly separated. The dynamics of the conformal mode is understood in terms of the oversubtraction due to the one loop counter term. The renormalization of the gravitational dressed operators is studied and their anomalous dimensions are computed. The exact s

R. Baier, G. Kunstatter, D. Schiff

The gauge dependence of the hot gluon self energy is examined in the context of Pisarski's method for resumming hard thermal loops. Braaten and Pisarski have used the Ward identities satisfied by the hard corrections to the n-point functions to argue the gauge fixing independence of the leading order resummed QCD plasma damping rate in covariant and strict C

Debashis Ghoshal, Dileep P. Jatkar, Sunil Mukhi

We investigate the nature of the ground ring of c=1 string theory at the special A-D-E points in the c=1 moduli space associated to discrete subgroups of SU(2). The chiral ground rings at these points are shown to define the A-D-E series of singular varieties introduced by Klein. The non-chiral ground rings relevant to closed-string theory are 3 real dimensi

Alon E. Faraggi, Benjamin Grinstein, Sydney Meshkov

Barbieri and Hall have argued that threshold effects at the scale of grand-unification wipe out predictions on the SUSY scale, M_S. Using triviality arguments we give upper bounds on ultraheavy particles, while proton stability gives lower bounds on the mass of the higgs color-triplet. We find no useful lower bound on the $\Sigma$ supermultiplet, but if the

J. R. Cudell, B. Margolis

We study the interface between soft and hard QCD at high energy and small momentum transfer. At LHC and SSC energies, we find that a cutoff BFKL equation leads one to expect a measurable perturbative component in traditionally soft processes. We show that the total cross section could become as large as 175 mb (122 mb) and the rho parameter 0.40 (0.25) at th

Nemanja Kaloper

The static stationary axially symmetric background ("infinite cosmic string") of the $D=4$ string theory provided with an axion charge is studied in the effective theory approach. The most general exact solution is constructed. It is found that the Kalb-Ramond axion charge, present in the string topology $R^{3} \times S^{1}$, produces nontrivial gravitationa

Jane H. MacGibbon, Robert H. Brandenberger

We calculate the flux of ultra high energy photons from individual ordinary (i.e. non-superconducting) cosmic strings and compare the results with the sensitivity of current and proposed TeV and EeV telescopes. Our calculations give only upper limits for the gamma ray flux, since the source of the photons, jets from particle production at cusps, may be weake

Chiara R. Nappi, Edward Witten

We present a conformal field theory -- obtained from a gauged WZW model -- that describes a closed, inhomogeneous expanding and recollapsing universe in $3+1$ dimensions. A possible violation of cosmic censorship is avoided because the universe recollapses just when a naked singularity was about to form. The model has been chosen to have $c=4$ (or $\widehat

A. M. Tsvelik

A novel approach to S =1/2 antiferromagnets with strong fluctuations based on the representation of spin-1/2 operators as bylinear forms of real (Majorana) fermions is suggested. This representation has the advantage of being irreducible without any constraints on the fermionic Hilbert space. This property allows to derive an effective Hamiltonian for low-ly

John Ellis, N. E. Mavromatos, D. V. Nanopoulos

We interpret Minkowski black holes as world-sheet {\it spikes } which are related by world-sheet { \it duality} to {\it vortices } that correspond to Euclidean black holes. These world-sheet defects induce defects in the gauge fields of the corresponding coset Wess-Zumino descriptions of spherically-symmetric black holes. The low-temperature target space-tim

Z. Bajnok, L. Palla, G. Takacs

Using the reduced WZNW formulation we analyse the classical $W$ orbit content of the space of classical solutions of the $A_2$ Toda theory. We define the quantized Toda field as a periodic primary field of the $W$ algebra satisfying the quantized equations of motion. We show that this local operator can be constructed consistently only in a Hilbert space con

Alexander Moroz

Thesis includes review on the large order behaviour of perturbation theory in quantum mechanical and field theory models; generalization of the Borel summability and strong asymptotic conditions to various (including horn-shaped) regions; discussion of analytic aspects of perturbation theory; examples which demonstrate differences between the Borel summabili

A. Das, E. Sezgin, Z. Khviengia

We consider two types of generalized self-duality conditions for Yang-Mills fields on paracomplex manifolds of arbitrary dimension. We then specialize to $3+3$ dimensions and show how one can obtain the KP equation from these self-duality conditions on $SL(2,R)$ valued gauge fields.

Johan Bijnens, Christophe Bruno, Eduardo de Rafael

We present a derivation of the low energy effective action of an extended Nambu Jona-Lasinio (ENJL) model to $O(p^4)$ in the chiral counting. Two alternative scenarios are considered on how the ENJL model could originate as a low energy approximation to QCD. The low energy effective Lagrangian we derive includes the usual pseudoscalar Goldstone modes, as wel

C. G. Boyd, D. E. Brahm, S. D. H. Hsu

We calculate contributions to the finite temperature effective action for the electroweak phase transition (EWPT) at $\O(g^4)$, {\it i.e.} at second order in $(g^2 T/\M)$ and all orders in $(g^2 T^2/\M^2)$. This requires plasma-mass corrections in the calculation of the effective potential, inclusion of the ``lollipop'' diagram, and an estimate of derivative

Sun Hong Rhie, David P. Bennett

A Hopf texture is a vacuum field configuration of isovector fields which is an onto map from the space as a large three sphere to the vacuum manifold $S^2$. We construct a Hopf texture with spherically symmetric energy density and discuss the topological charge. A Hopf texture collapses, and we study the collapse process numerically. In our simulations, it i

David P. Bennett, Albert Stebbins, Francois R. Bouchet

We compare the anisotropies in the cosmic microwave background radiation measured by the COBE experiment to the predictions of cosmic strings. We use an analytic model for the $\Delta T/T$ power spectrum that is based on our previous numerical simulations to show that the COBE results imply a value for the string mass per unit length, $\mu$ under the assumpt

Theodore J. Allen, Andrew J. Bordner

We write a Ginzburg-Landau Hamiltonian for a charged order parameter interacting with a background electromagnetic field in 2+1 dimensions. Using the method of Lund we derive a collective coordinate action for vortex defects in the order parameter and demonstrate that the vortices are charged. We examine the classical dynamics of the vortices and then quanti

J. R. Anglin, R. C. Myers

Revisions: reference added to: G. Gilbert, {\sl Nucl.Phys.} {\bf B328}, 159 (1989)

Randall D. Kamien, David R. Nelson

The statistical mechanics of directed line-like objects, such as directed polymers in an external field, strands of dipoles in both ferro- and electrorheological fluids, and flux lines in high-$T_{\tiny C}$ superconductors bears a close resemblance to the quantum mechanics of bosons in $2+1$ dimensions. We show that single component and binary mixture critic

David Thomas, David N. Schramm, Keith A. Olive, Brian D. Fields

The ability to now make measurements of Be and B as well as put constraints on \lisix\ abundances in metal-poor stars has led to a detailed reexamination of Big Bang Nucleosynthesis in the $A\groughly6$ regime. The nuclear reaction network has been significantly expanded with many new rates added. It is demonstrated that although a number of $A>7$ reaction r

Alexander Moroz

A generalized flux problem with Abelian and non-Abelian fluxes is considered. In the Abelian case we shall show that the generalized flux problem for tight-binding models of noninteracting electrons on either $2n$ or $2n+1$ dimensional lattice can always be reduced to a $n$ dimensional hopping problem. A residual freedom in this reduction enables to identify

K. Hamada

We discuss the quantum theory of 1+1 dimensional dilaton gravity, which is an interesting model with analogous features to the spherically symmetric gravitational systems in 3+1 dimensions. The functional measures over the metrics and the dilaton field are explicitly evaluated and the diffeomorphism invariance is completely fixed in conformal gauge by using

Robert H. Brandenberger, Anne-Christine Davis, Andrew M. Matheson, Mark Trodden

We consider grand unified theories with superconducting cosmic strings and which admit the mechanism for generating primordial magnetic fields recently discussed by Vachaspati. We show that these models are severely constrained by cosmological arguments. Quite generically, either stable springs or vortons will form. Provided the mass per unit length of the s