November 1995 arXiv papers — page 4

Paul Seidel

We define a homomorphism from (a certain extension of) the fundamental group of the Hamiltonian automorphism group of a symplectic manifold to the group of invertibles in its quantum cohomology ring. The manifold must satify a technical condition similar to weak monotonicity. This revised version has been entirely rewritten. It is more general and contains n

Curtis G. Callan,, Igor R. Klebanov

We construct the open string boundary states corresponding to various time-dependent deformations of the D-brane and explore several ways in which they may be used to study stringy soliton collective coordinate quantum dynamics. Among other things, we find that D-strings have exact moduli corresponding to arbitrary chiral excitations of the basic soliton. Th

L. Bonora, C. P. Constantinidis, E. Vinteler

We present a new realization of scalar integrable hierarchies in terms of the Toda lattice hierarchy. In other words, we show on a large number of examples that an integrable hierarchy, defined by a pseudodifferential Lax operator, can be embedded in the Toda lattice hierarchy. Such a realization in terms the Toda lattice hierarchy seems to be as general as

Jacek Dziarmaga

We consider slow motion of a pointlike topological defect (vortex) in the nonlinear Schrodinger equation minimally coupled to Chern-Simons gauge field and subject to external uniform magnetic field. It turns out that a formal expansion of fields in powers of defect velocity yields only the trivial static solution. To obtain a nontrivial solution one has to t

J. Bartels, H. Lotter, M. Vogt

A computer study is performed to estimate the influence of the small-$k_T$ region in the BFKL evolution equation. We consider the small-x region of the deep inelastic structure function $F_2$ and show that the magnitude of the small-$k_T$ region depends on $Q^2$ and $x_B$. We suggest that the width of the $\log k_T^2$-distribution in the final state may serv

O. Babelon, D. Bernard

We consider the universal solution of the Gervais-Neveu-Felder equation in the ${\cal U}_q(sl_2)$ case. We show that it has a quasi-Hopf algebra interpretation. We also recall its relation to quantum 3-j and 6-j symbols. Finally, we use this solution to build a q-deformation of the trigonometric Lam\'e equation.

Sujay Datta, Shantilal Das, Deshdeep Sahdev, Ravi Mehrotra

We critically review the fast algorithms for the numerical study of two--dimensional Josephson junction arrays and develop the analogy of such systems with electrostatics. We extend these procedures to arrays with bus--bars and defects in the form of missing bonds. The role of boundaries and of the guage choice in determing the Green's function of the sy

Anton Deitmar

It is shown that in a tower of coverings the regularized determinant of a generalized Laplacian converges to the $L^2$-determinant. This shows generic nontriviality of analytic torsion or regularized determinants since the $L^2$-counterparts are easier to compute. We further have an "Euler product expansion" for regularized determinants in terms of e

Francisco Gallego, B. P. Purnaprajna

In this article we determine exactly which line bundles on elliptic ruled surface X are normally presented. In particular we see that numerical classes of normally presented divisors form a convex set. (recall that Num(X) is generated by the class of a minimal section C_0 and by the class of a fiber f and that C_0 is ample.) As a corollary of the above resul

E. Alfinito, G. Profilo, G. Soliani

We study a modified version of an equation of the continuous Toda type in 1+1 dimensions. This equation contains a friction-like term which can be switched off by annihilating a free parameter $\ep$. We apply the prolongation method, the symmetry and the approximate symmetry approach. This strategy allows us to get insight into both the equations for $\ep =0

John R. Klauder

The long-standing problem of finding coherent states for the (bound state portion of the) hydrogen atom is positively resolved. The states in question: (i) are normalized and are parameterized continuously, (ii) admit a resolution of unity with a positive measure, and (iii) enjoy the property that the temporal evolution of any coherent state by the hydrogen

D. Galetti, J. T. Lunardi, B. M. Pimentel, C. L. Lima

Starting from the Schwinger unitary operator bases formalism constructed out of a finite dimensional state space, the well-known q-deformed commutation relation is shown to emerge in a natural way, when the deformation parameter is a root of unity.

Jorge M. Pacheco, Walter Ekardt, Wolf-Dieter Schoene

By combining the Self-Interaction Correction (SIC) with pseudopotential perturbation theory, the role of self-interaction errors inherent to the Local Density Approximation (LDA) to Density Functional Theory is estimated in the determination of ground state and low energy isomeric structures of small metallic clusters. Its application to neutral sodium clust

Walter Ekardt, Jorge M. Pacheco

Following Sham and Rice [L. J. Sham, T. M. Rice, Phys. Rev. 144 (1966) 708] the correlated motion of particle-hole pairs is studied, starting from the general two-particle Greens function. In this way we derive a matrix equation for eigenvalues and wave functions, respectively, of the general type of collective excitation of a N-particle system. The interpla

Arun Ram

The purpose of this paper is to describe a general procedure for computing analogues of Young's seminormal representations of the symmetric groups. The method is to generalize the Jucys-Murphy elements in the group algebras of the symmetric groups to arbitrary Weyl groups and Iwahori-Hecke algebras. The combinatorics of these elements allows one to compu

Arun Ram, Tom Halverson

Iwahori-Hecke algebras for the infinite series of complex reflection groups $G(r,p,n)$ were constructed recently in the work of Ariki and Koike, Broué and Malle, and Ariki. In this paper we give Murnaghan-Nakayama type formulas for computing the irreducible characters of these algebras. Our method is a generalization of that in our earlier paper in which we

Paul S. Aspinwall

We consider the general case of a type IIA string compactified on a Calabi-Yau manifold which has a heterotic dual description. It is shown that the nonabelian gauge symmetries which can appear nonperturbatively in the type II string but which are understood perturbatively in the heterotic string are purely a result of string-string duality in six dimensions

M. C. Diamantini, P. Sodano, C. A. Trugenberger

We show that the zero-temperature physics of planar Josephson junction arrays in the self-dual approximation is governed by an Abelian gauge theory with periodic mixed Chern-Simons term describing the charge-vortex coupling. The periodicity requires the existence of (Euclidean) topological excitations which determine the quantum phase structure of the model.

R. H. Rietdijk, J. W. van Holten

We present a theorem describing a dual relation between the local geometry of a space admitting a symmetric second-rank Killing tensor, and the local geometry of a space with a metric specified by this Killing tensor. The relation can be generalized to spinning spaces, but only at the expense of introducing torsion. This introduces new supersymmetries in the

B. E. Baaquie, R. Parwani

$ \hat {U}(1)$ Kac-Moody gauge fields have the infinite dimensional $ \hat{U}(1)$ Kac-Moody group as their gauge group. The pure gauge sector, unlike the usual $U(1)$ Maxwell lagrangian, is nonlinear and nonlocal; the Euclidean theory is defined on a $d+1$-dimensional manifold $ {\cal{R}}_d \times {\cal{S}}^1 $ and hence is also asymmetric. We quantize this

Hirosi Ooguri, Cumrun Vafa

We study the degenerating limits of superconformal theories for compactifications on singular K3 and Calabi-Yau threefolds. We find that in both cases the degeneration involves creating an Euclidean two-dimensional black hole coupled weakly to the rest of the system. Moreover we find that the conformal theory of A_n singularities of K3 are the same as that o

B. L. Ioffe

Contents: 1. The sum rules or $Γ_{p,n}$.Theoretical status. 2. Calculations of matrix elements over the polarized nucleon by the QCD sum rule approach. 3. Twist-4 corrections to $Γ_{p,n}$ from QCD sum rules. 4. Gerasimov, Drell-Hearn (GDH) sum rules. The estimate of higher twist corrections to $Γ_{p,n}$ using interpolation between $Γ_{p,n}$ and GDH sum rules

C. D. Froggatt

Different approaches to the fermion mass problem are reviewed. We illustrate these approaches by summarizing recent developments in models of quark and lepton mass matrices. Dynamical calculations of the top quark mass are discussed, based on (a) infrared quasi-fixed points of the renormalisation group equations, and (b) the multiple point criticality princi

N. Arteaga, C. Carimalo, P. Kessler, S. Ong

Using the general helicity formula for $γ^* γ^*$ collisions, we are showing that it should be possible to determine a number of independent ``structure functions'', i.e. linear combinations of elements of the two-photon helicity tensor, through azimuthal correlations in two-body or quasi two-body reactions induced by the photon-photon interaction, pr

J. Bijnens, G. Colangelo, G. Ecker, J. Gasser

We evaluate analytically the elastic $ππ$ scattering amplitude to two loops in chiral perturbation theory and give numerical values for the two $S$--wave scattering lengths and for the phase shift difference $δ_0^0-δ_1^1$.

G. Kramer, B. Lampe, H. Spiesberger

We discuss some theoretical uncertainties in the calculation of the cross section for charm production in charged current deep inelastic neutrino scattering related to ambiguities in the treatment of terms which are singular in the limit of a vanishing charm mass. In particular we compare the so-called variable flavour scheme where these terms are absorbed i

Nobuhiro Maekawa, Joe Sato

Recently one of the authors proposed a dual theory of a Supersymmetric Standard Model (SSM), in which it is naturally understood that at least one quark (the top quark) should be heavy, i.e., almost the same order as the weak scale, and the supersymmetric Higgs mass parameter $μ$ can naturally be expected to be small. Unfortunately, the model cannot possess

Rafael D. Sorkin

I describe the history of my attempts to arrive at a discrete substratum underlying the spacetime manifold, culminating in the hypothesis that the basic structure has the form of a partial-order (i.e. that it is a causal set).

Vicente Muñoz

We prove that every suitable $4$-manifold with $b_1=0$ and with an embedded Riemann surface of genus $2$ is of simple type. We find a relationship between the basic classes of two of these $4$-manifolds and those of the connected sum along the Riemann surface.

Vicente Muñoz

We use rudiments of the Seiberg-Witten gluing theory for trivial circle bundles over a Riemann surface to relate de Seiberg-Witten basic classes of two $4$-manifolds containing Riemann surfaces of the same genus and self-intersection zero with those of the $4$-manifold resulting as a connected sum along the surface. We study examples in which this is enough

Akhil Ranjan, G. Santhanam

In a complete Riemannian manifold $(M, g)$ if the hessian of a real valued function satisfies some suitable conditions then it restricts the geometry of $(M, g)$. In this paper we characterize all compact rank-1 symmetric spaces, as those Riemannian manifolds $(M, g)$ admitting a real valued function $u$ such that the hessian of $u$ has atmost two eigenvalue

J H Samson

The Hartree-Fock ground state phase diagram of the one-dimensional Hubbard model is calculated, constrained to uniform phases, which have no charge density modulation. The allowed solutions are saturated ferromagnetism (FM), a spiral spin density wave (SSDW) and a double spin density wave} (DSDW). The DSDW phase comprises two canted interpenetrating antiferr

Rudolf A. Römer, B. Sriram Shastry, B. Sutherland

We study the conservation laws of both the classical and the quantum mechanical continuum $1/r^2$ type systems. For the classical case, we introduce new integrals of motion along the recent ideas of Shastry and Sutherland (SS), supplementing the usual integrals of motion constructed much earlier by Moser. We show by explicit construction that one set of inte

Sandro Sorella

The low energy photoemission spectra in quantum antiferromagnets are studied by using several approximation-free calculations and rigorous theorems. The important and measurable property found is that the hole eigenstates with momenta differing by the antiferromagnetic wavevector $Q$ are equivalent and degenerate in energy. However the corresponding eigensta

Claudius Gros

We study the possibility of controlling the finite size corrections in exact diagonalization studies quantitatively. We consider the one- and two dimensional Hubbard model. We show that the finite-size corrections can be be reduced systematically by a grand-canonical integration over boundary conditions. We find, in general, an improvement of one order of ma

John Cardy

We analyse the effect of quenched uncorrelated randomness coupling to the local energy density of a model consisting of N coupled two-dimensional Ising models. For N>2 the pure model exhibits a fluctuation-driven first order transition, characterised by runaway renormalisation group behaviour. We show that the addition of weak randomness acts to stabilise th

V. Gasparian, E. Louis, J. A. Vergés

It is shown that the peak structure observed in angle-resolved photoelectron spectra of metallic deposits can only be unambiguously associated to single electronic states if the deposit has a two dimensional character (finite along one spatial direction). In one and zero dimensions the density of states shows peaks related to bunches of single electron state

Madhavan Ramamoorthy, Sokrates T. Pantelides

Oxygen migration in silicon corresponds to an apparently simple jump between neighboring bridge sites. Yet, extensive theoretical calculations have so far produced conflicting results and have failed to provide a satisfactory account of the observed $2.5$ eV activation energy. We report a comprehensive set of first-principles calculations that demonstrate th

Michael Blank

We investigate generalized phase transitions of type localization - delocalization from one to several Sinai-Bowen-Ruelle invariant measures in finite networks of chaotic elements (coupled map lattices) with general graphs of connections in the limit of weak coupling.

Ana Campos, Tom Shanks

In this paper we analyse the deep number counts problem, taking account of new observational and theoretical developments. First we show that the new Bruzual and Charlot (1993) models allow a new class of spiral dominated luminosity evolution (LE) model where significant amounts of the luminosity evolution needed to fit faint count data are due to spiral rat

T. Guillot, A. Burrows, W. B. Hubbard, J. I. Lunine

Using Doppler spectroscopy to detect the reflex motion of the nearby star, 51 Pegasi, Mayor \& Queloz (1995) claim to have discovered a giant planet in a 0.05-A.U., 4.23-day orbit. They estimate its mass to be in the range 0.5 \mj to 2 \mj, but are not able to determine its nature or origin. Including the effects of the severe stellar insolation implied, we

Adam Burrows, John Hayes

New data imply that the average velocity of radio pulsars is large \cite{hla93}. Under the assumption that these data imply that a pulsar is born with an ``intrinsic'' kick, we investigate whether such kicks can be a consequence of asymmetrical stellar collapse and explosion. We calculate the gravitational wave (GW) signature of such asymmetries due

Francisco Gallego, B. P. Purnaprajna

A ribbon D over a variety C is a scheme such that D_{red} = C, the ideal I in O_D of Cis a line bundle on C and I^2 = 0. A two dimensional ribbon is called a carpet. In this article we show that if D is a K3 carpet, that is a ribbon associated to a rational normal scroll with numerical invariants that of a K3 surface,then it can be smoothed to a K3 surface.

Martin Ebeling, Walter Nadler

We present a new method for investigating first-order phase transitions using Monte Carlo simulations. It relies on the multiple-histogram method and uses solely histograms of individual phases. In addition, we extend the method to include histograms of subphases. The free energy difference between phases, necessary for attributing the correct statistical we

R. Kantowski, T. Vaughan, D. Branch

Analytic expressions for distance-redshift relations which have been corrected for the effects of some inhomogeneities in the Friedmann-Robertson-Walker (FRW) mass density are used to illustrate the significance of inhomogeneities on a determination of $q_0$ made by using Type Ia supernovae. The value of $q_0$ inferred from a given set of observations depend

Sidney A. Bludman, Dallas C. Kennedy

Precise numerical standard solar models (SSMs) now agree with one another and with helioseismological observations in the convective and outer radiative zones. Nevertheless these models obscure how luminosity, neutrino production and g-mode core helioseismology depend on such inputs as opacity and nuclear cross sections. Although the Sun is not homologous, i

L. Hlavaty

Complete solution, more precisely, all invertible $4\times 4$ matrices $R,Q$ that solve Yang--Baxter system related to quantised braided groups, quantum doubles and other systems are given.

Boguslaw Broda

The paper is a chapter of the above-mentioned book. It aims to give an expository presentation of author's version of the non-Abelian Stokes theorem in the framework of path-integral formalism.

Maria Girone, Matthias Neubert

The $τ$ decay rate into hadrons of invariant mass smaller than $\sqrt{s_0}\ggΛ_{\rm QCD}$ can be calculated in QCD assuming global quark--hadron duality. It is shown that this assumption holds for $s_0>0.7$~GeV$^2$. From measurements of the hadronic mass distribution, the running coupling constant $α_s(s_0)$ is extracted in the range 0.7~GeV$^2<s_0<m_τ^2$. A

Jnanadeva Maharana

Ten dimensional type IIA and IIB theories with p-branes are compactified to 8-dimensions. It is shown that resulting branes can be classified according to the representations of $\bf {SL(3,Z) \times SL(2,Z)}$. These p-branes can also be obtained by compactification of M theory on three torus and various wrappings of membrane and five brane of the eleven dime

The ZEUS Collaboration

A measurement of inclusive charged particle distributions in deep inelastic $ep$ scattering for $γ^* p$ centre-of-mass energies $75< W < 175$~GeV and momentum transfer squared $10< Q^2 < 160$~GeV$^2$ from the ZEUS detector at HERA is presented. The differential charged particle rates in the $γ^* p$ centre-of-mass system as a function of the scaled longitudin

H-T. Sato

We discuss a relation between two-loop bosonic worldline Green functions which are obtained by Schmidt and Schubert in two different parametrizations of a two-loop worldline. These Green functions are transformed into each other by some transformation rules based on reparametrizations of the proper time and worldline modular parameters.

Rabindra N. Mohapatra, Andrija Rasin

It is shown that the minimal supersymmetric left-right model can provide a natural solution to the strong {\it CP} problem without the need for an axion, nor any additional symmetries beyond supersymmetry and parity.

A. H. Hoang, J. H. Kühn, T. Teubner

Recent analytic calculations on the rate for the production of a pair of massive fermions in $e^+ e^-$ annihilation plus real or virtual radiation of a pair of massless fermions are discussed. The contributions for real and virtual radiation are displayed separately. The asymptotic behaviour close to threshold is given in a compact form and an application to

Adrian Kent

Recent work with Dowker on the scientific status of the consistent histories approach to quantum theory is reviewed and summarised. The approach is compared with formulations of quantum theory, such as Bohmian mechanics and the Copenhagen interpretation a la Landau-Lifshitz, in which classical variables are explicitly appended. I try to explain why the consi

B. Sathiapalan

It is shown that the idea of ``minimal&#39;&#39; coupling to gauge fields can be conveniently implemented in the proper time formalism by identifying the equivalent of a ``covariant derivative&#39;&#39;. This captures some of the geometric notion of the gauge field as a connection. The proper time equation is also generalized so that the gauge invariances as

Gary A. Mamon

The DENIS $IJK$ survey of the entire southern sky is beginning observations this year. It will return one million images, representing 4 Terabytes, among which nearly $10^8$ stars and up to one million galaxies. The main extragalactic applications of such a multi-band, digital, near-IR 2D survey are listed, and the importance and feasibility of a spectroscop

A. C. Avram, E. Derrick, D. Jancic

The periods of the three-form on a Calabi-Yau manifold are found as solutions of the Picard-Fuchs equations; however, the toric varietal method leads to a generalized hypergeometric system of equations which has more solutions than just the periods. This same extended set of equations can be derived from symmetry considerations. Semi-periods are solutions of

T. M. Aliev, D. A. Demir, E. Iltan, N. K. Pak

The resolved and direct photon contributions to the single leptoquark (L) production process $γp\rightarrow L e$ are analysed for both scalar (S) and vector (V) leptoquarks in detail. It is shown that resolved photon contribution dominates for $M_{L}\leq 300 GeV$. For $M_{V}\geq 1 TeV$ and $M_{S}\geq 0.5 TeV$ cross section is completely determined by the dir

Johan Bijnens, Elisabetta Pallante, Joaquim Prades

We calculate the hadronic light-by-light contributions to the muon $g-2$. We use both $1/N_c$ and chiral counting to organize the calculation. Then we calculate the leading and next-to-leading order in the $1/N_c$ expansion low energy contributions using the Extended Nambu--Jona-Lasinio model as hadronic model. We do that to all orders in the external moment

Shrawan Kumar, M. S. Narasimhan

We prove that the Picard group of the moduli space of semistable G-bundles on any irreducible smooth projective curve is isomorphic with the group of integers.

Steve Bracker, Krishnaswamy Gounder, Kevin Hendrix, Don Summers

Offline software using TCP/IP sockets to distribute particle physics events to multiple UNIX/RISC workstations is described. A modular, building block approach was taken, which allowed tailoring to solve specific tasks efficiently and simply as they arose. The modest, initial cost was having to learn about sockets for interprocess communication. This multipr

R. Cosgrove

Rovelli&#39;s `` quantum mechanics without time&#39;&#39; motivates an intrinsically time-slicing independent picture of reduced phase space quantum gravity, which may be described as ``quantization after evolution&#39;&#39;. Sufficient criteria for carrying out quantization after evolution are developed in terms of a general concept of the classical limit o

M. A. R. Osorio, M. A. Vazquez-Mozo

We study quantum corrections for a family of 24 non-supersymmetric heterotic strings in two dimensions. We compute their genus two cosmological constant using the hyperelliptic formalism and the genus one two-point functions for the massless states. From here we get the mass corrections to the states in the massless sector and discuss the role of the infrare

A. M. Gavrilik, N. Z. Iorgov

Generators of multiparameter deformations $U_{q;s_1,s_2,...,s_{n-1}}(gl_n)$ of the universal enveloping algebra $U(gl_n)$ are realized bilinearly by means of appropriately generalized form of anyonic oscillators (AOs). This modification takes into account the parameters $s_1,...,s_{n-1}$ and yields usual AOs when all the $s_i$ are set equal to unity.

E. Krausmann, W. Balogh, H. Oberhummer, T. Rauscher

In neutron capture for magic--shell nuclei the direct reaction mechanism can be important and may even dominate. As an example we investigated the reaction $^{48}$Ca(n,$γ)^{49}$Ca for projectile energies below 250\,keV in a direct capture model using the folding procedure for optical and bound state potentials. The obtained theoretical cross sections are in

Max Petersen, Steffen Wilke, Paolo Ruggerone, Bernd Kohler

Recent measurements of the scattering of He and Ne atoms at Rh(110) suggest that these two rare-gas atoms measure a qualitatively different surface corrugation: While Ne atom scattering seemingly reflects the electron-density undulation of the substrate surface, the scattering potential of He atoms appears to be anticorrugated. An understanding of this perpl

Dieter Hennig, Maria Veronica Ganduglia-Pirovano, Matthias Scheffler

Using density-functional-theory we study the electronic and structural properties of a monolayer of Cu on the fcc (100) and (111) surfaces of the late 4d transition metals, as well as a monolayer of Pd on Mo bcc(110). We calculate the ground states of these systems, as well as the difference of the ionization energies of an adlayer core electron and a core e

Nora Breton, Tonatiuh Matos, Alberto Garcia

Within the metric structure endowed with two orthogonal space-like Killing vectors a class of solutions of the Einstein-Maxwell-Dilaton field equations is presented. Two explicitly given sub-classes of solutions bear an interpretation as colliding plane waves in the low-energy limit of the heterotic string theory.

M. J. Duff, H. Lu, C. N. Pope, E. Sezgin

The usual supermembrane solution of $D=11$ supergravity interpolates between $R^{11}$ and $AdS_4 \times round~S^7$, has symmetry $P_3 \times SO(8)$ and preserves $1/2$ of the spacetime supersymmetries for either orientation of the round $S^7$. Here we show that more general supermembrane solutions may be obtained by replacing the round $S^7$ by any seven-dim

Z. Khviengia, H. Lu, C. N. Pope, E. Sezgin

We study some low-lying physical states in a superstring theory based on the quadratically non-linear $SO(N)$--extended superconformal algebra. In the realisation of the algebra that we use, all the physical states are discrete, analogous to the situation in a one-scalar bosonic string. The BRST operator for the $N=3$ case needs to be treated separately, and

David M. Pierce

An extended free fermionic construction of the internal N=1 world sheet supercurrent for four-dimensional superstring theory is given. We show how it can describe theories with massless fermions, and we discuss the corresponding N=2 superconformal algebra. As an intermediate step, we show that an internal N=2 global superconformal invariance occurs in any su

Joseph Polchinski

This is a talk given at YKIS &#39;95, primarily to non-string theorists. I review the evidence for string duality, the principle that any string theory at strong coupling looks like another string theory at weak coupling. A postscript summarizes developments since the conference.

Carlo M. Becchi, Camillo Imbimbo

We present a very simplified analysis of how one can overcome the Gribov problem in a non-abelian gauge theory. Our formulae, albeit quite simplified, show that possible breakdowns of the Slavnov-Taylor identity could in principle come from singularities in space of gauge orbits. To test these ideas we exhibit the calculation of a very simple correlation fun

Hans-Peter Thienel

In the Bargmann-Fock representation the coordinates $z^i$ act as bosonic creation operators while the partial derivatives $\partial_{z^j}$ act as annihilation operators on holomorphic $0$-forms as states of a $D$-dimensional bosonic oscillator. Considering also $p$-forms and further geometrical objects as the exterior derivative and Lie derivatives on a holo

P. C. Argyres, M. R. Plesser, N. Seiberg, E. Witten

New examples of N=2 supersymmetric conformal field theories are found as fixed points of SU(2) N=2 supersymmetric QCD. Relations among the scaling dimensions of their relevant chiral operators, global symmetries, and Higgs branches are understood in terms of the general structure of relevant deformations of non-trivial N=2 conformal field theories. The spect

Alan Carey, Jouko Mickelsson, Michael Murray

We give an Atiyah-Patodi-Singer index theory construction of the bundle of fermionic Fock spaces parametrized by vector potentials in odd space dimensions and prove that this leads in a simple manner to the known Schwinger terms (Faddeev-Mickelsson cocycle) for the gauge group action. We relate the APS construction to the bundle gerbe approach discussed rece

Saleev V. A

A study of the $\J$-meson photoproduction at large transverse momentum at HERA energies via the charm quark excitation in the photon is presented. Based on perturbative QCD, nonrelativistic quark model and photon structure function formalism, our calculation demonstrates that the charm content of the photon may be very important for the $\J$ photoproduction

Zheng Huang, Ina Sarcevic, Robert Thews, Xin-Nian Wang

We present a novel method for studying the formation of a disoriented chiral condensate (DCC) in high-energy hadronic and heavy-ion collisions utilizing a discrete wavelet transformation. Due to its salient feature of space-scale locality, the discrete wavelet proves to be very effective in probing physics simultaneously at different locations in phase space

Piotr Bialas

We study the correlation functions in the branched polymer model. Although there are no correlations in the grand canonical ensemble, when looking at the canonical ensemble we find negative long range power like correlations. We propose that a similar mechanism explains the shape of recently measured correlation functions in the elongated phase of 4d simplic

Fintan D. Ryan

The effect of gravitational radiation reaction on orbits around a spinning black hole is analyzed. Such orbits possess three constants of motion: $ι$, $e$, and $a$, which correspond, in the Newtonian limit of the orbit being an ellipse, to the inclination angle of the orbital plane to the hole&#39;s equatorial plane, the eccentricity, and the semi-major axis

Donald E. Neville

The metric for plane gravitational waves is quantized using the Ashtekar field variables. The z axis (direction of travel of the waves) is taken to be the entire real line. Solutions to the constraints are proposed; they involve open-ended flux lines running along the entire z axis. These solutions are annihilated by the constraints except at the two boundar

Richard J. Epp

In the (2+2) formulation of general relativity spacetime is foliated by a two-parameter family of spacelike 2-surfaces (instead of the more usual one-parameter family of spacelike 3-surfaces). In a partially gauge-fixed setting (double-null gauge), I write down the symplectic structure of general relativity in terms of intrinsic and extrinsic quantities asso

Andrei Linde, Arthur Mezhlumian

We show that there exists a large class of regularization schemes for probabilistic predictions in the theory of a self-reproducing inflationary univere, all of which eliminate the apparent dependence on the time reparametrization. However, all these schemes lead to different answers for relative probabilities of finding various types of post-inflationary un

Johannes Richter, Andreas Voigt, Sven E. Krüger, Claudius Gros

We investigate the spin 1/2 Heisenberg star introduced in J. Richter and A. Voigt, J. Phys. A: Math. Gen. {\bf 27}, 1139 (1994). The model is defined by $H=J_1 \sum_{i=1}^{N}{{\bf s}_0{\bf s}_i} + J_2 H_{R}\{{\bf s}_i\}$ ; $J_1,J_2 \ge 0$ , $i=1,...,N$. In extension to the Ref. we consider a more general $H_{R}\{{\bf s}_i\}$ describing the properties of the

Tohru Kawarabayashi, Tomi Ohtsuki

Diffusion of electrons in two-dimensional disordered systems with spin-orbit interactions is investigated numerically. Asymptotic behaviors of the second moment of the wave packet and of the temporal auto-correlation function are examined. At the critical point, the auto-correlation function exhibits the power-law decay with a non-conventional exponent $α$ w

M. E. Zhitomirsky, I. A. Zaliznyak

We calculate the effect of zero-point fluctuations on the magnetostatic properties of a quasi one-dimensional antiferromagnetic helimagnet with and without in-plane anisotropy. We find substantial reduction of the uniform susceptibility and the sublattice magnetization from their classical values and appreciable renormalization of the spin-flop field at $T=0

Janet Cahn

Expectations about the correlation of cue phrases, the duration of unfilled pauses and the structuring of spoken discourse are framed in light of Grosz and Sidner&#39;s theory of discourse and are tested for a directions-giving dialogue. The results suggest that cue phrase and discourse structuring tasks may align, and show a correlation for pause length and

Francois R. Molino, J. M. Barthez, A. Ayral, C. Guizard

We report here on experimental and numerical studies of the influence of surfactants on mineral gel synthesis. The modification of the gel structure when the ratios water-precursor and water-surfactant vary is brought to the fore by fractal dimension measures. A property of {\em polydispersity of the initial hydrolysis} is proposed to explain these results,

Andreas Reisenegger

The X-ray emission by hot gas around the central galaxies of galaxy clusters is commonly modeled assuming the existence of steady-state, multiphase cooling flows. The inflowing gas will be chemically enriched by type Ia supernovae and stellar mass loss occurring in the outer parts of the central galaxy. This may give rise to a substantial metallicity enhance

J. Perez, J-J Aly

The so-called ``symplectic method&#39;&#39; is used for studying the linear stability of a self-gravitating collisionless stellar system, in which the particles are also submitted to an external potential. The system is steady and spherically symmetric, and its distribution function $f_0$ thus depends only on the energy $E$ and the squarred angular momentum

J. S. Bagla, T. Padmanabhan, J. V. Narlikar

Thanks to new technology of observations and fresh inputs from particle physics, cosmology has advanced on both observational and theoretical fronts. It is therefore opportune that we take stock of the cosmological situation today and examine the observational and theoretical constraints as they are now. The bottom line in this review is that despite the ava

J. Huston, E. Kovacs, S. Kuhlmann, H. L. Lai

The CDF experiment has reported an excess of high-$p_t$ jets compared to previous next-to-leading order QCD expectations. Before attributing this to new physics effects, we investigate whether these high-$p_t$ jets can be explained by a modified gluon distribution inside the proton. We find enough flexibility in a global QCD analysis including the CDF inclus

A. Bartl, H. Eberl, K. Hidaka, T. Kon

We present a complete calculation of the QCD corrections (of the order $α_s$) to the width of the decay $H^+ \to t \bar{b}$ within the Minimal Supersymmetric Standard Model. We find that the QCD corrections are quite important, and that the supersymmetric QCD corrections (due to gluino, stop and sbottom exchange) can be comparable to or even larger than the

Suzhou Huang, Marcello Lissia

We show that QCD undergoes dimensional reduction at high temperatures also in the quark sector. In the kinematic region relevant to screening physics, where the lowest Matsubara modes are close to their ``mass-shells&#39;&#39;, all static Green&#39;s functions involving both quarks and gluons, are reproducible in the high-$T$ limit by a renormalizable three

Gary A. Mamon

The links between the internal structure of galaxy groups and clusters and cosmological parameters are reviewed here. The mass density profiles of clusters, inferred from both optical analyses of the galaxy surface number density profile coupled with internal kinematics, and from weak gravitational lensing, appear cuspy with inner density profiles at least a

Manoelito M. de Souza

The problems of Classical Electrodynamics with the electron equation of motion and with non-integrable singularity of its self-field stress tensor are well known. They are consequences, we show, of neglecting terms that are null off the charge world line but that gives a non null contribution on its world line. The self-field stress tensor of a point classic

S. M. Sergeev, V. V. Bazhanov, V. V. Mangazeev

This paper has been temporarily withdrawn for corrections.

Henric Rhedin

We consider the supersymmetric WZNW model gauged in a manifestly supersymmetric way. We find the BRST charge and the necessary condition for nilpotency. In the BRST framework the model proves to be a Lagrangian formulation of the supersymmetric coset construction, known as the N=1 Kazama-Suzuki coset construction.

Mirjam Cvetic, Paul Langacker

Within a class of superstring vacua which have an additional non-anomalous $U(1)&#39;$ gauge factor, we address the scale of the $U(1)&#39;$ symmetry breaking and constraints on the exotic particle content and their masses. We also show that an extra gauge $U(1)&#39;$ provides a new mechanism for generating a naturally small effective $μ$ term. In general, e