November 1993 arXiv papers — page 7

Moti Gitik

A model with a sequence of indiscernibles depending on a particular precovering set is constructed.The initial assumption is as follows: for every n<omega the set {alpha | o(alpha)=alpha^+n } is unbounded in kappa.

Denise E. Freed

The dissipative Hofstadter model, which describes a particle in 2-D subject to a periodic potential, uniform magnetic field, and dissipation, is also related to open string boundary states. This model exhibits an SL(2,Z) duality symmetry and hidden reparametrization invariance symmetries. These symmetries are useful for finding exact solutions for correlatio

Djordje Šijački

We extend previous work on the IR regime approximation of QCD in which the dominant contribution comes from a dressed two-gluon effective metric-like field $G_{μν} = g_{ab} B^{a}_μ B^{b}_ν$ ($g_{ab}$ a color SU(3) metric). The ensuring effective theory is represented by a pseudo-diffeomorphisms gauge theory. The second -quantized $G_{μν}$ field, together wit

M. Blagojevic, T. Vukasinac

We consider a Hamiltonian analysis of the Liouville theory and construction of symmetry generators using Castellani&#39;s method. We then discuss the light-cone gauge fixed theory. In particular, we clarify the difference between Hamiltonian approaches based on different choices of time, $ξ^0$ and $ξ^+$. Our main result is the construction of SL(2,R) symmetr

M. Blagojevic

The Liouville action emerges as the effective action of 2-d gravity in the process of path integral quantization of the bosonic string. It yields a measure of the violation of classical symmetries of the theory at the quantum level. Certain aspects of the residual SL(2,R) invariance of the gauge-fixed Liouville theory are disscussed. ( Lectures presented at

Milan Mijic

There are several ways to establish and study thermal properties of black holes. I review here method of Fulling and Ruijsenaars, based on the analytic structure of Green functions on the complex plane. This method provides a clear distinction between zero and finite temperature field theories, and allows for quick evaluation of black hole temperature. (Lect

Mico Durdevic

A noncommutative-geometric generalization of the theory of principal bundles is sketched. A differential calculus over corresponding quantum principal bundles is analysed. The formalism of connections is presented. In particular, operators of covariant derivative and horizontal projection are described and analysed. Quantum counterparts for the Bianchi ident

O. V. Dodlov, S. E. Konstein, M. A. Vasiliev

Matrix generalizations of the N-particle quantum-mechanical Calogero model classifying according to representations of the symmetric group $S_N$ are considered. Symmetry properties of the eigen-wave functions in the matrix Calogero models are analyzed. Latex.

R. Sasaki

An algebraic approach to integrable quantum field theory with a boundary (a half line) is presented and interesting algebraic equations, Reflection equations (RE) and Reflection Bootstrap equations (RBE) are discussed. The Reflection equations are a consistent generalisation of Yang-Baxter equations for factorisable scatterings on a half line (or with a refl

Z. Bern, L. Dixon, D. A. Kosower

We discuss new results in QCD obtained with string-based methods. These methods were originally derived from superstring theory and are significantly more efficient than conventional Feynman rules. This technology was a key ingredient in the first calculation of the one-loop five-gluon amplitude. We also present a conjecture for a particular one-loop helicit

Samir D. Mathur

We argue that a basic modification must be made to the first quantised formalism of string theory if the physics of `particle creation&#39; is to be correctly described. The analogous quantisation of the relativistic particle is performed, and it is shown that the proper time along the world line must go both forwards and backwards (in the usual quantisation

Carl H. Albright, Satyanarayan Nandi

A new procedure is developed which enables one to start from the quark and lepton mass and mixing data at the low scale and construct mass matrices which exhibit simple SO(10) structure at the SUSY GUT scale. This approach is applied to the present data involving quark and charged lepton masses, the CKM mixing matrix and the MSW solar neutrino and atmospheri

C. -P. Yuan, L. Nodulman, H. Baer, V. Barger

The top group studied discovery issues as well as measurements to be made at the Tevatron, the LHC and the SSC.

B. Ananthanarayan, Q. Shafi

We estimate the top quark, lightest sparticle (LSP) and scalar higgs masses within a supersymmetric grand unified framework in which $\tanβ\simeq m_t/m_b$ and the electroweak symmetry is radiatively broken. The requirement that the calculated $b$ quark mass lie close to its measured value, together with the cosmological constraint $Ω_{LSP} \approx 1$, fixes

A. C. Pearson

We show that in the real time formalism, the generating functional for thermal Green functions does not factorise. However for most calculations, the normal real time Feynman rules can still be used to give correct results.

Geert Jan van Oldenborgh

When computing the properties of reactions involving unstable charged particles care has to be taken to use a gauge invariant amplitude. In this talk we present methods to (automatically) obtain such an amplitude, both at the tree level and in one-loop calculations, using only a minimal number of diagrams. The numerical difference with gauge variant methods

M. Carena, M. Olechowski, S. Pokorski, C. E. M. Wagner

The infrared quasi fixed point solution for the top quark mass in the Minimal Supersymmetric Standard Model explains in a natural way large values of the top quark mass and appears as a prediction in many interesting theoretical schemes. Moreover, as has been recently pointed out, for moderate values of $\tanβ$, in order to achieve gauge and bottom-tau Yukaw

Jeffrey Grandy, Rajan Gupta

The topological susceptibility of the quenched QCD vacuum is measured on large lattices for three $β$ values from $6.0$ to $6.4$. Charges possibly induced by $O(a)$ dislocations are identified and shown to have little effect on the measured susceptibility. As $β$ increases, fewer such questionable charges are found. Scaling is checked by examining the ratios

Martin Luescher

Lattice QCD with an even number of degenerate quark flavours is shown to be a limit of a local bosonic field theory. The action of the bosonic theory is real and bounded from below so that standard simulation algorithms can be expected to apply. The feasibility of such calculations is discussed, but no practical tests have yet been made.

S. M. Catterall, F. R. Devlin, I. T. Drummond, R. R. Horgan

Following the Non-Relativistic QCD approach we use a gauge invariant smearing method with factorization to measure the excitation energies for a heavy $Q\bar{Q}$ system on a $24^3\times 48$ lattice at $β=6.2$. The results come from averaging over an ensemble of 60 QCD configurations. In order to enhance the signal from each configuration we use wall sources

Tamás G. Kovaács, E. T. Tomboulis

We rewrite the two-dimensional SU(2)$\times$ SU(2) chiral spin model in terms of SO(3) and {\bf Z}$_2$ degrees of freedom. The transformation, which is motivated by a similar representation of the corresponding lattice gauge theory in higher dimensions, exhibits the presence of dynamical SO(3) vortices and associated strings. We present arguments that (pairs

V. Khatsymovsky

In the (3+1)D Hamiltonian Regge calculus (one of the coordinates, $ t$, is continuous) conjugate variables are (defined on triangles of discrete 3D section $ t=const$) finite connections and antisymmetric area bivectors. The latter, however, are not independent, since triangles may have common edges. This circumstance can be taken into account with the help

R. Graham, H. Luckock

We solve the quantum constraints for homogeneous N=1 supergravity on 3-geometries with a Bianchi IX metric. Because these geometries admit Killing vectors with the same commutation relations as the angular momentum generators, there are two distinct definitions of homogeneity. The first of these is well-known and has been shown by D'Eath to give the wormhole

L. Bergomi, Th. Jolicoeur

We study the electronic states of isolated fullerene anions C$^{n-}_{60}$ ($1\le n \le 6$) taking into account the effective interaction between electrons due to exchange of intramolecular phonons. If the vibronic coupling is strong enough such an effect may overwhelm Hund&#39;s rule and lead to an ordering of levels that can be interpreted as on-ball pairin

Y. Xian

After a proper definition of the dimerization order parameter for a spin-$S$ system, I show that this order parameter in the $SU(n)$ ($n=2S+1$) antiferromagnetic chains (or equivalently the $SU(2)$ spin-$S$ chains with Hamiltonians which project out singlet states) is, in the thermodynamic limit, directly proportional to the staggered-magnetization in the co

Herbert W. Hamber

Some first results are presented regarding the behavior of invariant correlations in simplicial gravity, with an action containing both a bare cosmological term and a lattice higher derivative term. The determination of invariant correlations as a function of geodesic distance by numerical methods is a difficult task, since the geodesic distance between any

UKQCD Collaboration

We calculate the leading-order matrix element for the decay $B \to K^* γ$ in the quenched approximation of lattice QCD on a $24^3 \times 48$ lattice at $β=6.2$, using an O(a)-improved fermion action. Extrapolating the quark masses to their physical values we obtain an on-shell form factor of $T_1(q^2=0)=0.15+12-14$, where the errors quoted are purely statist

Saleem Zaroubi, Yehuda Hoffman

The clustering in redshift space is studied here to first order within the framework of gravitational instability. The distortion introduced by the peculiar velocities of galaxies results in anisotropy in the galaxy distribution and mode-mode coupling when analyzed in Fourier space. An exact linear calculation of the full covariance matrix in both the real a

L. Koyrakh

Nonperturbative corrections up to $m_b^{-2}$ to the heavy lepton energy distributions are investigated in the inclusive semileptonic weak decays of heavy flavors in QCD. In the case of $B$-meson decays, for $b \ra uτ\bnu$ transitions they decrease the decay rate by 6\% of its perturbative value, while for $b \ra cτ\bnu$ they decrease it by 10\%.

B. Grammaticos, F. W. Nijhoff, V. Papageorgiou, A. Ramani

We present particular solutions of the discrete Painlevé III (d-P$\rm_{III}$) equation of rational and special function (Bessel) type. These solutions allow us to establish a close parallel between this discrete equation and its continuous counterpart. Moreover, we propose an alternate form for d-P$\rm_{III}$ and confirm its integrability by explicitly deriv

G. Chanfray, P. Schuck, G. Welke

The occurrence of poles in the $2π$ propagator in a hot pion medium is studied. The domain of non--trivial solutions to the corresponding bosonic gap equation is investigated as a function of the chemical potential and temperature of the gas.

R. J. Furnstahl

Apparent inconsistencies between different formulations of nucleon sum rules at finite density are resolved through a proper accounting of asymmetries in the spectral functions between positive- and negative-energy states.

I. Zahed

I discuss a comprehensive approach to the spacelike physics in high temperature QCD in three dimensions. The approach makes use of dimensional reduction. I suggest that this approach is useful for high temperature QCD in four dimensions.

Christopher M. O&#39;Neill

We study the classical theory of a non-Abelian gauge field (gauge group $SU(2)$) coupled to a massive dilaton, massive axion and Einstein gravity. The theory is inspired by the bosonic part of the low-energy heterotic string action for a general Yang-Mills field, which we consider to leading order after compactification to $(3+1)$ dimensions. We impose the c

S. -H. H. Tye

A brief review of the motivation and the present status of Fractional Superstring is presented. Talk at ``Strings 93&#39;&#39;, Berkeley, May 1993.

V. V. Mangazeev, S. M. Sergeev, Yu. G. Stroganov

In this paper we present a new series of 3-dimensional integrable lattice models with $N$ colors. The case $N=2$ generalizes the elliptic model of our previous paper. The weight functions of the models satisfy modified tetrahedron equations with $N$ states and give a commuting family of two-layer transfer-matrices. The dependence on the spectral parameters c

R. Brout, S. Massar, S. Popescu, R. Parentani

We show how to apply post selection in the context of weak measurement of Aharonov and collaborators to construct the quantum back reaction on a classical field. The particular case which we study in this paper is pair creation in an external electric field and the back reaction is the counter field produced by the pair \underline {as} it is made. The constr

Oliver Rudolph

A set of Green functions ${\cal G}_α(x-y), α\in [0, 2 π[$, for free scalar field theory is introduced, varying between the Hadamard Green function $Δ_1(x-y) \equiv \linebreak[2] \lsta{0} \hspace{-0.1cm} \{ φ(x), φ(y) \} \hspace{-0.1cm} \rsta{0}$ and the causal Green function ${\cal G}_π(x-y) = i Δ(x-y) \equiv [φ(x), φ(y)]$. For every $α\in [0, 2 π[$ a path-i

Ovid C. Jacob

Recently, we have proposed a new front-form quantization which treated both the $x^{+}$ and the $x^{-}$ coordinates as front-form &#39;times.&#39; This quantization was found to preserve parity explicitly. In this paper we extend this construction to local Abelian gauge fields . We quantize this theory using a method proposed originally by Faddeev and Jackiw

Ovid C. Jacob

Recently, we proposed a new front-form quantization which treated both the $x^{+}$ and the $x^{-}$ coordinates as front-form &#39;times.&#39; This quantization was found to preserve parity explicitly. In this paper we extend this construction to fermion fields in the context of the Yukawa theory. We quantize this theory using a method proposed originally by

Georg G. Raffelt

The experimental and astrophysical status of neutrino masses is reviewed with an emphasis on the cosmologically interesting regime.

A. Kundu, T. De, B. Dutta-Roy

Some results are presented indicating the distinct advantages that accrue from choosing a real representation for the generators of SU(N) rather than the usual and more popular Gell-Mann type matrices. A few examples in the context of quantum chromodynamics are used to serve as illustrations.

R. Guida, K. Konishi, N. Magnoli

We report the "state of the art" of the problem of $B+L$ violation in high-energy electroweak scatterings. Results of various analyses point toward (though do not prove rigorously yet) the "half-suppression", i.e., that the $B+L$ violating cross section remains suppressed at least by the negative exponent of the single instanton action, at all energies. Most

I. I. Bigi

Theoretical descriptions for the nonleptonic decays of heavy flavour hadrons have emerged that incorporate non-perturbative corrections in a systematic way and are genuinely based on QCD. One can reproduce $τ(D^+)/τ(D^0)$, $BR_{SL}(D^+)$ and $BR_{SL}(D^0)$ as due mainly to destructive interference in $D^+$ decays; one predicts $τ(B^-)$ to exceed $τ(B_d)$ by

Ken Yee

We introduce a minimally interacting pure gauge compact U(1)xU(1) model consistent with abelian projection symmetries. This paradigm, whose interactions are entirely due to compactness, illustrates how compactness can contribute to interspecies interactions. Furthermore, it has a much richer phase structure(including a magnetically confining phase) than obta

Sutapa Mukherji, Somendra M. Bhattacharjee

The anomalous exponent, $η_{p}$, for the decay of the reunion probability of $p$ vicious walkers, each of length $N$, in $d$ $(=2-ε)$ dimensions, is shown to come from the multiplicative renormalization constant of a $p$ directed polymer partition function. Using renormalization group(RG) we evaluate $η_{p}$ to $O(ε^2)$. The survival probability exponent is

D. Poilblanc, W. Hanke, D. J. Scalapino

Scattering by a single impurity introduced in a strongly correlated electronic system is studied by exact diagonalization of small clusters. It is shown that an inert site which is spinless and unable to accomodate holes can give rise to strong resonant scattering. A calculation of the local density of state reveals that, for increasing antiferromagnetic exc

Michael Ma, Pornthep Nisamaneephong, Lizeng Zhang

After an introduction to the dirty bosons problem, we present a gaussian theory for the ground state and excitations. This approach is physically equivalent to the Bogoliubov approximation. We find that ODLRO can be destroyed with sufficient disorder. The density of states and localization of the elementary excitations are discussed. (To appear in JLTP Proce

J. I. Katz

Relativistic blast wave models predict the spectrum of the emitted synchrotron radiation. The electrons in the shocked region are heated to a Wien distribution whose ``temperature&#39;&#39; is $1/3$ of the mean electron energy. This energy scale determines a characteristic (break) frequency of synchrotron radiation. At much lower frequencies a spectrum $F_nu

Y. Hoffman

The large scale structure of the universe is reconstructed by means of the Wiener filter and constrained realizations of Gaussian fields. The density field constructed from optically selected galaxies (Hudson \cite{Hudson}) has been sampled out to a distance of $80\hmpc$. This data set is used for the reconstruction of the underlying primordial perturbation

Kin-Wang Ng

We consider the production of gravitons in an inflationary cosmology by approximating each epoch of change in the equation of state as sudden, from which a simple analytic graviton mode function has been derived. We use this mode function to compute the graviton spectral energy density and the tensor-induced cosmic microwave background anisotropy. The result

P. Berglund, S. Katz

By means of toric geometry we study hypersurfaces in weighted projective space of dimension four. In particular we compute for a given manifold its intrinsic topological coupling. We find that the result agrees with the calculation of the corresponding coupling on the mirror model in the large complex structure limit.

Yu. A. Simonov

The background field formalism is used to implement nonperturbative QCD contributions into diagrammatic technic at $T>0$. The leading terms both in the confining and nonconfining phase are identified at large $N_c$ and the transition temperature is calculated in this limit, which appears to be in good agreement with the Monte Carlo calculations.

Yu. A. Simonov

The structure of the hadron spectrum is discussed in connection with the main phenomena of nonperturbative QCD: confinement and chiral symmetry breaking (CSB). For the higher part of the spectrum ($M \ge 2 GeV$) spin and chiral effects are unimportant; spectrum of $q\bar{q}$ system is described by an effective Hamiltonian deduced from QCD. The Hamiltonian re

John David Crawford

Bifurcation problems in which periodic boundary conditions (PBC) or Neumann boundary conditions (NBC) are imposed often involve partial differential equations that have Euclidean symmetry. In this case posing the bifurcation problem with either PBC or NBC on a finite domain can lead to a symmetric bifurcation problem for which the manifest symmetries of the

Peter A. Henning

Transport coefficients are obtained by incorporating a gauge principle into thermo field dynamics of inhomogeneous systems. In contrast to previous derivations, neither imaginary time arguments nor perturbation theory in powers of a coupling constant are used in the calculation. Numerical values are calculated for the pion component in hot nuclear matter.

Robert H. Gilman

A study of triangulations of cycles in the Cayley diagrams of finitely generated groups leads to a new geometric characterization of hyperbolic groups.

Krešimir Demeterfi, Igor R. Klebanov, Gyan Bhanot

We consider (1+1)-dimensional QCD coupled to scalars in the adjoint representation of the gauge group SU($N$). This model results from dimensional reduction of the (2+1)-dimensional pure glue theory. In the large-N limit we study the spectrum of glueballs numerically, using the discretized \lcq. We find a discrete spectrum of bound states, with the density o

D. Bernard, V. Pasquier, D. Serban

We describe a few properties of the XXX spin chain with long range interaction. The plan of these notes is: 1. The Hamiltonian 2. Symmetry of the model 3. The irreducible multiplets 4. The spectrum 5. Wave functions and statistics 6. The spinon description 7. The thermodynamics

C. Klimcik, A. A. Tseytlin

We consider a class of $2+D$ - dimensional string backgrounds with a target space metric having a covariantly constant null Killing vector and flat `transverse&#39; part. The corresponding sigma models are invariant under $D$ abelian isometries and are transformed by $O(D,D)$ duality into models belonging to the same class. The leading-order solutions of the

D. T. Barclay, Avinash Khare, U. Sukhatme

It has previously been proved that the lowest order supersymmetric WKB approximation reproduces the exact bound state spectrum of shape invariant potentials. We show that this is not true for a new, recently discovered class of shape invariant potentials and analyse the reasons underlying this breakdown of the usual proof.

Naoya Hata, Paul Langacker

Various theoretical uncertainties in the standard solar model and in the Mikheyev-Smirnov-Wolfenstein (MSW) analysis are discussed. It is shown that two methods of estimating the solar neutrino flux uncertainties are equivalent: (a) a simple parametrization of the uncertainties using the core temperature and the nuclear production cross sections; (b) the Mon

Gregory Mahlon

We use the solutions to the recursion relations for double-off-shell fermion currents to compute helicity amplitudes for $n$-photon scattering and electron-positron annihilation to photons in the massless limit of QED. The form of these solutions is simple enough to allow {\it all}\ of the integrations to be performed explicitly. For $n$-photon scattering, w

Mark B. Wise

An introduction to the heavy quark effective theory and its symmetries is given. Some implications of the heavy quark spin and flavor symmetries are discussed. Recent results on fragmentation to quarkonium states are reviewed.

R. Ugoccioni, A. Giovannini, S. Lupia

We explore the consequences of considering clans real physical objects in the framework of a generalized version of the Simplified Parton Shower model for a single jet. We predict that the average number of clans at fixed energy grows linearly in rapidity and slowly decreases with energy in a fixed rapidity interval.

Agustin Nieto

Perturbative calculations in field theory at finite temperature involve sums over the Matsubara frequencies. Besides the usual difficulties that appear in perturbative computations, these sums give rise to some new obstacles that are carefully analized here. I present a fast and realible recipe to work out sums over the Matsubara frequencies. As this algorit

D. Morgan

A high priority in light spectroscopy is to seek out and characterize various types of non-$(Q\bar{Q}$) meson. The large quantity of new data now appearing will present a great opportunity. To identify the non-$(Q\bar{Q}$) intruders one needs to know the regular $(Q\bar{Q}$) pattern well; whole meson families thus become a target for close investigation. A p

P. Kroll

Recent improvements of the hard scattering picture for exclusive reactions, namely the inclusion of both Sudakov corrections and the intrinsic transverse momentum dependence of the hadronic wave function, are reviewed. On account of these improvements the perturbative contribution to the pion&#39;s form factor can be calculated in a theoretically self-consis

Gye T. Park

We perform a combined analysis of two stringent constraints on the 2 Higgs doublet model, one coming from the recently announced CLEO II bound on $B(b \rightarrow s γ)$ and the other from the recent LEP data on $ε_b$. We have included one-loop vertex corrections to $Z \rightarrow b \overline b$ through $ε_b$ in the model. We find that the new $ε_b$ constrain

S. Antonelli, M. Bellacci, A. Donini, R. Sarno

We present the first tests and results from a study of QCD with two flavours of dynamical Wilson fermions using the Hybrid Monte Carlo Algorithm (HMCA) on APE100 machines.

S. Tertychniy

The new method of invariant definition of the measurable angle of light deflection in the static central symmetric gravitational field is suggested. The predicted pure gravitational contribution to the deflection angle slightly differs from its classical estimate and one may hope that this discrepancy could be experimentally detected in the near future. (uue

L. Biferale, M. Blank, U. Frisch

We define a (chaotic) deterministic variant of random multiplicative cascade models of turbulence. It preserves the hierarchical tree structure, thanks to the addition of infinitesimal noise. The zero-noise limit can be handled by Perron-Frobenius theory, just as the zero-diffusivity limit for the fast dynamo problem. Random multiplicative models do not poss

Robert Ferrell, Edmund Bertschinger

We describe an efficient Particle-Mesh algorithm for the Connection Machine CM-5. Our particular method parallelizes well and the computation time per time step decreases as the particles become more clustered. We achieve floating-point computation rates of 4--5 MFlops/sec/processing node and total operations (the sum of floating-point and integer arithmetic

Takashi Chiba, Naoshi Sugiyama, Yasushi Suto

We have performed the most comprehensive predictions of the temperature fluctuations \dtt in the primeval isocurvature baryon models to see whether or not the models are consistent with the recent data on the cosmic microwave background anisotropies. More specifically, we computed the \dtt corresponding to the experimental set-up by the South-Pole and the Ow

R. Kormann, P. Schneider, M. Bartelmann

We construct a simple elliptical gravitational lens model for the quadruple lens B1422+231 and show that the details of the configuration cannot be easily understood in terms of this model; in particular, the flux ratios of the images are hard to reproduce. This qualitatively verifies the results from a different lens model constructed for the same object by

Sandip K. Chakrabarti, Sydney D&#39;Silva

We study the dynamics of toroidal magnetic flux tubes, symmetric about the rotation axis, inside non-magnetic thick accretion disks around black holes. We present model equations which include effects of gravity, centrifugal force, pressure gradient force, Coriolis force, drag, magnetic tension and magnetic buoyancy. We solve them assuming the disk to be adi

Sydney D&#39;Silva, Sandip K. Chakrabarti

In paper I, we have studied the conditions under which flux tubes are expelled from adiabatic thick accretion disks. In the present paper, we explore a few other models of thick disks, where flux tubes could be stored. We show that flux tubes with sufficiently weak fields are not expelled out if they move adiabatically inside an isothermal disk; they continu

M. Bartelmann, P. Schneider

We demonstrate that high-redshift 1-Jansky radio sources are correlated with foreground IRAS galaxies on angular scales of several 10 arc minutes on a statistical significance level of up to 99.8\%. Based on a theoretical analysis published earlier, we propose to interpret these correlations in terms of gravitational lensing by large- scale structures.

Konstadinos Sfetsos

We consider gauged WZW models based on a four dimensional non-semi-simple group. We obtain conformal $\s$-models in $D=3$ spacetime dimensions (with exact central charge $c=3$) by axially and vectorially gauging a one-dimensional subgroup. The model obtained in the axial gauging is related to the $3D$ black string after a correlated limit is taken in the lat

Larry McLerran, Raju Venugopalan

We show that the gluon distribution function for very large nuclei may be computed for small transverse momentum as correlation functions of an ultraviolet finite two dimensional Euclidean field theory. This computation is valid to all orders in the density of partons per unit area, but to lowest order in $α_s$. The gluon distribution function is proportiona

S. T. Petcov, A. Yu. Smirnov

The MSW or vacuum oscillation solution of the solar neutrino problem can be reconciled with possible existence of the $(ββ)_{0ν}$ decay with a half-life corresponding to an effective Majorana mass of the electron neutrino $|m_{ee}| \cong (0.1 - 1.0)~$eV. The phenomenological consequences of such a possibility are analyzed and the implications for the mechani

C. Blecken, Y. Chen, K. A. Muttalib

We present long range statistical properties of a recently introduced unitary random matrix ensemble, whose short range correlations were found to describe a transition from Wigner to Poisson type as a function of a single parameter.

A. C. Davis, A. P. Martin

When a fermion interacts with a global vortex or cosmic string a solenoidal &#34;gauge&#34; field is induced. This results in a non-trivial scattering cross-section. For scalars and non-relativistic fermions the cross-section is similar to that of Aharonov and Bohm, but with corrections. A cosmological example is compared to one in liquid He$^{3}$-A and impo

A. C. Davis, A. P. Martin, N. Ganoulis

The scattering of a charged fermion from an electroweak or semi-local string is investigated and a full solution obtained for both massive and massless cases. For the former, with fractional string flux, there is a helicity conserving and helicity-flip cross-section, of equal magnitude and of a modified Aharonov-Bohm form: for integer flux the strong interac

Christian Grosche

In this paper path integration in two- and three-dimensional spaces of constant curvature is discussed: i.e.\ the flat spaces $\bbbr^2$ and $\bbbr^3$, the two- and three-dimensional sphere and the two- and three dimensional pseudosphere. The Laplace operator in these spaces admits separation of variables in various coordinate systems. In all these coordinate

Mourad E. H. Ismail, Mizan Rahman

By splitting the real line into intervals of unit length a doubly infinite integral of the form $\Int F(q^x)\,dx,\; 0<q<1$, can clearly be expressed as $\Integ \Sum F(q^{x+n})\,dx$, provided $F$ satisfies the appropriate conditions. This simple idea is used to prove Ramanujan&#39;s integral analogues of his \ph{1}{1} sum and give a new proof of Askey and Roy

Ashoke Sen, Barton Zwiebach

We prove local background independence of the complete quantum closed string field theory using the recursion relations for string vertices and the existence of connections in CFT theory space. Indeed, with this data we construct an antibracket preserving map between the state spaces of two nearby conformal theories taking the corresponding string field meas

F. P. Devecchi, H. O. Girotti

We argue that a consistent quantization of the Floreanini-Jackiw model, as a constrained system, should start by recognizing the improper nature of the constraints. Then each boundary conditon defines a problem which must be treated sparately. The model is settled on a compact domain which allows for a discrete formulation of the dynamics; thus, avoiding the

Tze-Dan Chung, Herman Verlinde

A simple quantum mechanical model of $N$ free scalar fields interacting with a dynamical moving mirror is formulated and shown to be equivalent to two-dimensional dilaton gravity. We derive the semi-classical dynamics of this system, by including the back reaction due to the quantum radiation. We develop a hamiltonian formalism that describes the time evolut

H. Nishino

We show that the super-Lax operator for $~N=1$~ supersymmetric Kadomtsev-Petviashvili equation of Manin and Radul in three-dimensions can be embedded into recently developed self-dual supersymmetric Yang-Mills theory in $~2+2\-$dimensions, based on general features of its underlying super-Lax equation. The differential geometrical relationship in superspace

Alan Kostelecky, Malcolm Perry

Using a combination of analytical and numerical methods, we obtain a two-dimensional spacetime describing a black hole with tachyon hair. The physical ADM mass of the black hole is finite. The presence of tachyon hair increases the Hawking temperature.

Andre LeClair

We present a new application of affine Lie algebras to massive quantum field theory in 2 dimensions, by investigating the $q\to 1$ limit of the q-deformed affine $\hat{sl(2)}$ symmetry of the sine-Gordon theory, this limit occurring at the free fermion point. Working in radial quantization leads to a quasi-chiral factorization of the space of fields. The con

J. R. Reyes Martínez

We apply the theory of superselection sectors in the same way as done by G.Mack and V.Schomerus for the Ising model to generalizations of this model described by J.Fröhlich and T.Kerler.

M. Arik, V. Gabay

We consider a Kaluza-Klein theory whose ground state is ${\bf R}^4 \times {\bf M } \times {\bf K}$ where ${\bf M}$ and ${\bf K}$ are compact, irreducible, homogenous internal mani folds. This is the simplest ground state compatible with the existence of the graviton, gauge fields, massless scalar fields and the absence of the cosmological constan t. The requ

I. I. Bigi

Second-generation theoretical technologies -- heavy quark expansions, QCD sum rules and QCD simulations on the lattice -- are arriving on the scene, allowing a treatment of charm decays that is genuinely based on QCD. The availability of those theoretical tools strengthens the case for the need for comprehensive precision measurements of charm decays. It is

P V Landshoff

I discuss (i) hadron-hadron and photon-hadron total cross-sections, (ii) elastic scattering, (iii) the rôle of minijets in total cross-sections and the need to include them in Monte-Carlos for small-$x$ structure functions, (iv) how the two pomerons affect small-$x$ behaviour, and (v) rapidity-gap physics.

Takemi Hayashi, Masahisa Matsuda, Morimitsu Tanimoto

We give the detailed analyses for the gluonic-penguin effect on the $\kp$ and $\pp$ decays of the $B$ meson. In the standard model, it is shown that the ratio $BR(B\A\kp)/BR(B\A\pp)$ takes the value $0.5\sim 3.0$ with the strongly depending on the CP violating phase $ϕ$ and the KM matrix element $|V_{ub}|$. We obtain the constraint on the form factor by usin

Roger Dashen, Elizabeth Jenkins, Aneesh V. Manohar

A systematic expansion in 1/N is constructed for baryons in QCD. Predictions of the 1/N expansion at leading and subleading order for baryon axial current coupling constant ratios such as F/D, baryon masses and magnetic moments are derived. The baryon sector of QCD has a light quark spin-flavor symmetry at leading order in 1/N. The formalism of induced repre

Stefan Kappler, Paul Rakow

We consider a particular case of the two dimensional Blume-Emery-Griffiths model to study the finite-size scaling for a field driven first-order phase transition with two coexisting phases not related by a symmetry. For low temperatures we verify the asymptotic (large volume) predictions of the rigorous theory of Borgs and Kotecky, including the predictions

V. Khatsymovsky

In quantum Regge calculus areas of timelike triangles possess discrete spectrum. This is because bivectors of these triangles are variables canonically conjugate to orthogonal connection matrices varying in the compact group. (The scale of quantum of this spectrum is nothing but Plankian one). This is checked in simple exactly solvable model - dimensionally