April 1995 arXiv papers — page 3

T. R. Marsh

We have found that the white dwarf PG 1101+364 is a double-lined white dwarf/white dwarf binary with an orbital period of 3.47 hours. PG 1101+364 is the shortest period detached double-degenerate yet found and gravitational radiation will cause it to merge in 2.5 X 10**9 years. PG 1101+364 has a mass ratio of 0.87 +/- 0.03. From the relative strengths of the

Yi Hu

We expose in detail the principle that the relative geometric invariant theory of equivariant morphisms is related to the GIT for linearizations near the boundary of the $G$-effective ample cone. We then apply this principle to construct and reconstruct various universal moduli spaces. In particular, we constructed the universal moduli space over $\overline{

C. Michael

We analyse the sum rules describing the action and energy in the colour fields around glueballs, torelons and static potentials.

Adrian L. Melott, B. S. Sathyaprakash, Varun Sahni

The potential is a constant to linear order in cosmological gravitational clustering. In this Letter we present results of testing the conjecture, proposed by Pauls and Melott (1995), that the effect of nonlinear evolution on the potential can be better described by smoothing it on the scale of nonlinearity. We show two-dimensional simulations consisting of

H. C. Rosu, M. Reyes, K. B. Wolf, O. Obregón

We present a supersymmetric analysis of the wave problem with a Demkov-Ostrovsky spherically symmetric class of focusing potentials at zero energy. Following a suggestion of Lévai, we work in the so-called R_0=0 sector in order to obtain the superpartner (fermionic) potentials within Witten's supersymmetric procedure. General solutions of the superpotent

Matias Zaldarriaga, Diego D. Harari

We develop an analytic method and approximations to compute the polarization induced in the cosmic microwave background radiation on a wide range of angular scales by anisotropic Thomson scattering in presence of adiabatic scalar {(energy-density)} linear fluctuations. The formalism is an extension to the polarized case of the analytic approach recently deve

Francesco Sylos Labini, Luca Amendola

A crucial issue in cosmology is the determination of the fluctuation power spectrum.The standard picture of the matter clustering, the Cold Dark Matter model (and its variant), assumes that,on scales smaller than a certain ``flattening scale'' $λ_f$, the power spectrum increases with the scale, while on much larger scales it decreases so to match the

Karthik A. Iyer, Michael P. Merrick, Thomas L. Beck

In the distributed nucleus approximation we represent the singular nucleus as smeared over a smallportion of a Cartesian grid. Delocalizing the nucleus allows us to solve the Poisson equation for theoverall electrostatic potential using a linear scaling multigrid algorithm.This work is done in the context of minimizing the Kohn-Sham energy functionaldirectly

A. Smilga

We consider pure $SU(2)$ Yang-Mills theory when the space is compactified to a 3-dimensional sphere with finite radius. The Euclidean classical self-dual solutions of the equations of motion (the instantons) and the static finite energy solutions (the sphalerons) which have been found earlier are rewritten in handy physical variables with the gauge condition

Katsuyuki Sugiyama

For a one-parameter family of Calabi-Yau d-fold M embedded in ${{CP}^{d+1}}$, we consider a new quasi-topological field theory ${A^{\ast}}$(M)-model compared with the $A$(M)-model. The two point correlators on the sigma model moduli space (the hermitian metrics) are analyzed by the $A{A^{\ast}}$-fusion on the world sheet sphere. A set of equations of these c

Katsuyuki Sugiyama

Using mirror symmetry in Calabi-Yau manifolds M, three point functions of A(M)-model operators on the genus $0$ Riemann surface in cases of one-parameter families of $d$-folds realized as Fermat type hypersurfaces embedded in weighted projective spaces and a two-parameter family of $d$-fold embedded in a weighted projective space ${\amb}$ are studied. These

R. F. Werner

For a quantum observable $A_\hbar$ depending on a parameter $\hbar$ we define the notion ``$A_\hbar$ converges in the classical limit''. The limit is a function on phase space. Convergence is in norm in the sense that $A_\hbar\to0$ is equivalent with $\Vert A_\hbar\Vert\to0$. The $\hbar$-wise product of convergent observables converges to the product

R. Chakrabarti, R. Jagannathan

A finite-dimensional matrix representation of the Jackson $q$-differential operator $D_q$, defined by $D_qf(x)$ $=$ $(f(qx)-f(x))/(x(q-1))$, is written down following Calogero. Such a representation of $D_q$ should have applications in $q$-analysis leading to the corresponding extensions of the numerous results of Calogero's work.

R. M. Kashaev

The link invariant, arising from the cyclic quantum dilogarithm via the particular $R$-matrix construction, is proved to coincide with the invariant of triangulated links in $S^3$ introduced in R.M. Kashaev, Mod. Phys. Lett. A, Vol.9 No.40 (1994) 3757. The obtained invariant, like Alexander-Conway polynomial, vanishes on disjoint union of links. The $R$-matr

Yi-Zhi Huang

This is the third part of the revised versions of the notes of three consecutive expository lectures given by Chongying Dong, Haisheng Li and Yi-Zhi Huang in the conference on Monster and vertex operator algebras at the Research Institute of Mathematical Sciences, Kyoto, September 4-9, 1994. In this part, we discuss an $S_{3}$-symmetry of the Jacobi identity

Haisheng Li

This is the second part of the revised versions of the notes of three consecutive expository lectures given by Chongying Dong, Haisheng Li and Yi-Zhi Huang in the conference on Monster and vertex operator algebras at the Research Institute of Mathematical Sciences, Kyoto, September 4-9, 1994. In this part, we discuss the commutativity, the associativity, the

Chongying Dong

This is the first part of the revised versions of the notes of three consecutive expository lectures given by Chongying Dong, Haisheng Li and Yi-Zhi Huang in the conference on Monster and vertex operator algebras at the Research Institute of Mathematical Sciences, Kyoto, September 4-9, 1994. In this part we review the definitions of vertex operator algebras

G. Q. Li, C. M. Ko, G. E. Brown

Using a relativistic transport model for the expansion stage of S+Au collisions at 200 GeV/nucleon, we show that the recently observed enhancement of low-mass dileptons by the CERES collaboration can be explained by the decrease of vector meson masses in hot and dense hadronic matter.

Dietrich Bödeker, Larry McLerran, Andrei Smilga

It has been argued by Grigoriev and Rubakov that one can simulate real time processes involving baryon number non-conservation at high temperature using real time evolution of classical equations, and summing over initial conditions with a classical thermal weight. It is known that such a naive algorithm is plagued by ultraviolet divergences. In quantum theo

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

There are at present two known string theories in $(2,2)$ dimensions. One of them is the well known $N=2$ string, and the other one is a more recently constructed $N=1$ spacetime supersymmetric string. They are both based on certain twistings and/or truncations of the small $N=4$ superconformal algebra, realised in terms of $(2,2)$ superspace variables. In t

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

In this paper we construct a $(2,2)$ dimensional string theory with manifest $N=1$ spacetime supersymmetry. We use Berkovits' approach of augmenting the spacetime supercoordinates by the conjugate momenta for the fermionic variables. The worldsheet symmetry algebra is a twisted and truncated ``small'' $N=4$ superconformal algebra. The realisation

Ansar Fayyazuddin

We comment on some aspects of the semiclassical BPS saturated states close to the curve $Im a_{D}/a =0$

H. E. Boos

This work is a continuation of paper (hep-th/9407146) where the Boltzmann weights for the N-state integrable spin model on the cubic lattice has been obtained only numerically. In this paper we present the analytical formulae for this model in a particular case. Here the Boltzmann weights depend on six free parameters including the elliptic modulus. The obta

M. Requardt

Starting from the hypothesis that both physics, in particular space-time and the physical vacuum, and the corresponding mathematics are discrete on the Planck scale we develop a certain framework in form of a '{\it cellular network}' consisting of cells interacting with each other via bonds. Both the internal states of the cells and the "strength

Peter Levay, David McMullan, Izumi Tsutsui

In this paper we investigate the form of induced gauge fields that arises in two types of quantum systems. In the first we consider quantum mechanics on coset spaces G/H, and argue that G-invariance is central to the emergence of the H-connection as induced gauge fields in the different quantum sectors. We then demonstrate why the same connection, now giving

F. S. NAVARRA, M. NIELSEN, C. A. A. NUNES, M. TEIXEIRA

Using a $\overline D$ meson cloud model we calculate the squared charm radius of the nucleon . The ratio between this squared radius and the ordinary baryon squared radius is identified with the probability of ``seeing'' the intrinsic charm component of the nucleon. Our estimate is compatible with those used to successfully describe the charm product

Dennis Silverman

In the main part of the paper we project forward to having $B$ factory determinations of $\sin(2β)$ and $\sin(2α)$, for which we take several values. First, we use a joint $χ^2$ analysis of CKM experiments to constrain CKM matrix elements in the standard model, and experiments on the angles $α$, $β$, and $γ$, and on $x_s$ and null $CP$ asymmetries. Then we i

Joannis Papavassiliou

We report new results in the study of CP violation in semileptonic top decays, in the context of the Weinberg Model.

Alberto Sirlin

The phenomenological evidence for electroweak corrections in the Standard Model, both at very low energies and the $Z^0$ scale, is discussed. In particular, we review a simple but sharp argument for the presence of Electroweak Bosonic Corrections.

Joannis Papavassiliou

Some of the most important theoretical and phenomenological aspects of the pinch technique are presented, and several recent developments are briefly reviewed.

Kostas Philippides

We outline the pinch technique for constructing gauge invariant Green's functions in gauge theories and derive the Ward identities that must be satisfied by the gauge invariant three boson vertices of the standard model. They are generalizations of their tree level Ward identities and are shown to be crucial for the delicate gauge cancellations of the S-

Joannis Papavassiliou

Using the S--matrix pinch technique we obtain to one loop order gauge independent $γW^-W^+$ and $Z W^-W^+$ vertices in the context of the standard model, with all incoming momenta off--shell. We show that the vertices so constructed satisfy simple QED--like Ward identities. These gauge invariant vertices give rise to expressions for the magnetic dipole and e

Dan-di Wu

We use the natural $SU(3)\times U(1)$ global symmetry of the gauge-fermion interaction sector of the standard model to discuss the fermion mass hierarchy problem. The $SU(3)$ sixtet and triplet Higgs are introduced. The Yukawa sector is partially symmetric. The smaller the symmetry of a Yukawa term, the smaller its coupling constant. The mass hierarchy is a

Boris Kopeliovich, Bogdan Povh

A new scaling variable is introduced in terms of which nuclear shadowing in deep-inelastic scattering is universal, i.e. independent of $A$, $Q^2$ and $x$. This variable can be interpreted as a measure of the number of gluons probed by the hadronic fluctuations of a virtual photon during their lifetime. According to recent data from the H1 and ZEUS experimen

Joerg Huefner, Boris Kopeliovich

We calculate the nuclear suppression for $J/Ψ$ and $Ψ'$ production within a coupled channel approach in the subspace of the $J/Ψ$ and $Ψ'$ states. We are able to explain, why (i) the $J/Ψ$ and $Ψ'$ show the same suppression from $200\ GeV$ to $800\ GeV$ in proton-nucleus collisions and why (ii) the $Ψ'$ is absorbed more strongly than the $J/Ψ

M. Spira, A. Djouadi, D. Graudenz, P. M. Zerwas

Gluon fusion is the main production mechanism for Higgs particles at the LHC. We present the QCD corrections to the fusion cross sections for the Higgs boson in the Standard Model, and for the neutral Higgs bosons in the minimal supersymmetric extension of the Standard Model. The QCD corrections are in general large and they increase the cross sections signi

S. A. Kulagin, W. Melnitchouk, G. Piller, W. Weise

We study deep-inelastic scattering from polarized nuclei within a covariant framework. A clear connection is established between relativistic and non-relativistic limits, which enables a rigorous derivation of convolution formulae for the spin-dependent nuclear structure functions g_1^A and g_2^A in terms of off-mass-shell extrapolations of polarized nucleon

Yen-Chung Lin

We construct the effective anomaly lagrangian involving nucleons and photons by using current-current coupling method. The contribution of this lagrangian to the anomalous magnetic moment of nucleon is purely isovector. The anomalous magnetic moment of proton, $κ_P$, can be calculated from the this lagrangian and it is found to be $κ_P^{Theor.} = 1.77$, whic

C. H. Jin, E. A. Paschos

A field theoretic description for inclusive semileptonic B meson decays is formulated. We argue that large regions of the phase spaces for the decays are dominated by distances near the light cone. The light-cone dominance allows to incorporate nonperturbative QCD effects in a distribution function. A one-to-one correspondence with the heavy quark effective

W. Buchmuller, A. Hebecker

We demonstrate that the global properties of the ``rapidity gap'' events, observed at HERA, can be understood based on electron-gluon scattering as the underlying partonic process. Using the measured inclusive structure function $F_2$ to determine the parameters of the parton model, the diffractive structure function $F_2^D$ is predicted. The ratio o

Riccardo Barbieri, Lawrence Hall, Alessandro Strumia

The flavor changing and CP violating phenomena predicted in supersymmetric unified theories as a consequence of the large top quark Yukawa coupling, are investigated in the quark sector and compared with related phenomena in the lepton sector, considered previously. In particular we study $\varepsilon_K$, $\varepsilon_K'/\varepsilon_K$, $Δm_B$, $b\to sγ$

Nils A. Törnqvist

It is shown that one can fit the available data on the a0(980), f0(980), f0(1300) and K*0(1430) mesons as a distorted 0++ qq bar nonet using very few (5-6) parameters and an improved version of the unitarized quark model. This includes all light two-pseudoscalar thresholds, constraints from Adler zeroes, flavour symmetric couplings, unitarity and physically

T. Kobayashi

We study nonrenormalizable coupling terms in $Z_N$ orbifold models. Nontrivial selection rules of couplings are provided and cannot be understood in terms of a simple symmetry of effective field theories. We also discuss phenomenological implications of theses selection rules for the quark mass matrices.

K. Kobayakawa, Y. Sato, S. Tanaka

We would like to point out the possibility to detect the low-energy signals of moduli in the superstring theory in the neutrino oscillation. The idea is based on the characteristics that the couplings of moduli are different in matter. We estimate the oscillation probability both in the long baseline and in the solar neutrino oscillations and examine the det

Gye T. Park

Concentrating on the impact of the very recent top quark discovery, we perform a combined analysis of two strongest constraints on the 2 Higgs doublet model, one coming from the recent measurement by CLEO on the inclusive branching ratio of b->s γdecay and the other from the recent LEP data on Z->b b-bar decay. We have included the model predictions for one-

Naoyuki HABA, Chuichiro HATTORI, Masahisa MATSUDA, Takeo MATSUOKA

In the underlying Planck scale theory we introduce a certain type of discrete symmetry, which potentially brings the stability of the weak-scale hierarchy under control. Under the discrete symmetry the $μ$-problem and the tadpole problem can be solved simultaneously without relying on some fine-tuning of parameters. Instead, it is required that doublet Higgs

Jemal Guven, Niall Ó Murchadha

We continue our examination of the constraints in spherically symmetric general relativity begun in I (gr-qc/9411009) and II (gr-qc/9411010). We extend to general configurations with $J\ne 0$ the analysis of II which treated a moment of time symmetry. We exploit the one parameter family of foliations introduced in I which are linear and homogeneous in the ex

Louis Crane

We investigate the possibility that the quantum theory of gravity could be constructed discretely using algebraic methods. The algebraic tools are similar to ones used in constructing topological quantum field theories.The algebraic tools are related to ideas about the reinterpretation of quantum mechanics in a general relativistic context.

D. Z. Liu, K. Levin, Y. Zha

We analyze neutron experiments on $\ybco$ at various stoichiometries in the superconducting state, within the context of a bi-layer theory which yields good agreement with the normal state Cu-NMR and neutron data as a function of ω, q and T. A d-wave superconducting state exhibits peaks at q = ( π, π, π) and sharp maxima as a function of ω, at twice the gap

P. B. Wiegmann

We outline the basic ideas of the topological mechanisms of superconductivity. A gauged model of correlated electronic system where a topological fluid is formed as a result of a strong interaction is discussed.

C. Micheletti, F. Seno, J. M. Yeomans

We present analytic evidence for the occurrence of an upsilon point, an infinite checkerboard structure of modulated phases, in the ground state of a spin model. The structure of the upsilon point is studied by calculating interface--interface interactions using an expansion in inverse spin anisotropy.

Karsten Flensberg, Ben Yu-Kuang Hu, Antti-Pekka Jauho, Jari M. Kinaret

We report a fully microscopic theory for transconductivity, or, equivalently, momentum transfer rate, of Coulomb coupled electron systems. We use the Kubo linear response formalism, and our main formal result expresses the transconductivity in terms of two fluctuation diagrams, which are topologically related, but not equivalent to, the Aslamazov-Larkin diag

M. Kolesik, M. Suzuki

The antiferromagnetic three-state Potts model on the simple-cubic lattice is studied using Monte Carlo simulations. The ordering in a medium temperature range below the critical point is investigated in detail. Two different regimes have been observed: The so-called broken sublattice-symmetry phase dominates at sufficiently low temperatures, while the phase

M. Fannes, R. F. Werner

For classical lattice systems, the Dobrushin-Lanford-Ruelle theory of boundary conditions states that the restriction of a global equilibrium state to a subsystem can be obtained as an integral over equilibrium states of the subsystem alone. The Hamiltonians for the subsystem are obtained by fixing a configuration for the variables in the complement of the s

Harald Baayen, Richard Sproat

Given a previously unseen form that is morphologically n-ways ambiguous, what is the best estimator for the lexical prior probabilities for the various functions of the form? We argue that the best estimator is provided by computing the relative frequencies of the various functions among the hapax legomena --- the forms that occur exactly once in a corpus. T

Esther Koenig

We present the LexGram system, an amalgam of (Lambek) categorial grammar and Head Driven Phrase Structure Grammar (HPSG), and show that the grammar formalism it implements is a well-structured and useful tool for actual grammar development.

Matthias Bartelmann, Ramesh Narayan

We propose a new technique, which we call the lens parallax method, to determine simultaneously the redshift distribution of the faint blue galaxies and the mass distributions of foreground clusters of galaxies. The method is based on gravitational lensing and makes use of the following: (1) the amplitude of lensing-induced distortions of background galaxies

Arnon Dar, Nir J. Shaviv

Blazar emission of gamma rays and cosmic ray production of gamma rays in gas-rich clusters have been proposed recently as alternative sources of the high energy extragalactic diffuse gamma ray background radiation. We show that these sources also produce a very different high energy extragalactic diffuse neutrino background radiation. This neutrino backgroun

Arnon Dar

The recently observed Deuterium abundance in a low- metallicity high-redshift hydrogen cloud, which is about ten times larger than that observed in the near interstellar medium, is that expected from the Standard Big Bang Nucleosynthesis theory and the observed abundances of $^4$He and $^7$Li extrapolated to their primordial values. The inferred cosmic baryo

Glennys R. Farrar, Edward W. Kolb

There are good reasons to consider models of low-energy supersymmetry with very light photinos and gluinos. In a wide class of models the lightest $R$-odd, color-singlet state containing a gluino, the $\r0$, has a mass in the 1-2 GeV range and the slightly lighter photino, $\pho$, would survive as the relic $R$-odd species. For the light photino masses consi

F. De Paolis, G. Ingrosso, Ph. Jetzer, M. Roncadelli

Recent observations of microlensing events in the Large Magellanic Cloud suggest that a sizeable fraction of the galactic halo is in form of MACHOs with mass less than abou 0.1 M_{\odot}. Here we argue that molecular clouds (mainly H_2) located in the galactic halo can contribute substantially to its total mass. We outline a scenario in which dark clusters o

David R. Morrison

Given two Calabi--Yau threefolds which are believed to constitute a mirror pair, there are very precise predictions about the enumerative geometry of rational curves on one of the manifolds which can be made by performing calculations on the other. We review the mechanics of making these predictions, including a discussion of two conjectures which specify ho

O. Aharony, J. Sonnenschein, S. Yankielowicz

We present more examples of dual N=1 SUSY gauge theories. This set of theories is connected by flows to both Seiberg's and Kutasov's dual theories. This provides a unifying picture of the various dual theories. We investigate the dual theories, their flat directions and mass perturbations.

M. Dubinin

We consider three jet production at high $p_T$ in the $γγ\to q \bar q g$ process and calculate quark and gluon jet spectra. The possibility of quark-gluon jet separation is discussed and compared with the $e^+ e^- \to q \bar q g$ case.

Zhi-zhong Xing

Within the standard electroweak model we point out that the $3\times 3$ matrix of quark mixing is characterized by three universal (rephasing-invariant) quantities: one of them for $CP$ violation and the other two for off-diagonal asymmetries. Unitarity of the quark mixing matrix can in principle be tested through a variety of measurements which are irreleva

Ehud Reiter

One of the most important questions in applied NLG is what benefits (or `value-added', in business-speak) NLG technology offers over template-based approaches. Despite the importance of this question to the applied NLG community, however, it has not been discussed much in the research NLG community, which I think is a pity. In this paper, I try to summar

A. UDALSKI, M. SZYMANSKI, J. KALUZNY, M. KUBIAK

We present the second part of the OGLE Catalog of Periodic Variable Stars in the Galactic bulge. 800 variable stars found in four Baade's Window fields BW1, BW2, BW3 and BW4 are presented. Among them 71 are classified as pulsating, 465 as eclipsing and 264 as miscellaneous type. The Catalog and individual observations are available in digital form from t

D. Kotschick

We show that minimal symplectic 4--manifolds with $b_2^+ >1$ and with residually finite fundamental groups are irreducible. We also give examples of irreducible orientable four--manifolds with indefinite intersection forms which are not almost complex with respect to either orientation.

Pradip Kumar Sahu

The highlights and main results of this work can be summarized as follows : (1) The energy per nucleon of cold nuclear matter, derived by us using chiral sigma model, is in good agreement with the preliminary estimates inferred from heavy-ion collision data in the density range between one to four times the nuclear saturation density. (2) For a system of hig

Cheongho Han, Andrew Gould

The mass function of 51 Massive Compact Objects (MACHOs) detected toward the Galactic bulge is statistically estimated from Einstein ring crossing times $t_{\rm e}$. For a Gaussian mass function, the best fitting parameters are $\langle \log (m/M_{\odot}) \rangle = -1.12$ and $σ_{\log (m/M_{\odot})} = 0.57$. If the mass function follows a power-law distribut

Hyun-Chul Kim, Andree Blotz, Maxim V. Polyakov, Klaus Goeke

The electromagnetic form factors of the SU(3) octet baryons are investigated in the semibosonized SU(3) Nambu--Jona-Lasinio model (chiral quark-soliton model). The rotational $1/N_c$ and strange quark mass corrections in linear order are taken into account. The electromagnetic charge radii of the nucleon and magnetic moments are also evaluated. It turns out

L. Rozansky

We establish a relation between the coefficients of asymptotic expansion of trivial connection contribution to Witten's invariant of rational homology spheres and the invariants that T.~Ohtsuki extracted from Witten's invariant at prime values of $K$. We also rederive the properties of prime $K$ invariants discovered by H.~Murakami and T.~Ohtsuki. We

M. Chaichian, A. P. Demichev

We construct path integral representations for the evolution operator of q-oscillators with root of unity values of q-parameter using Bargmann-Fock representations with commuting and non-commuting variables, the differential calculi being q-deformed in both cases. For $q^2=-1$ we obtain a new form of Grassmann-like path integral.

Paolo M. Gensini

We present in this contribution the basic formulæ for the analysis of low--momentum charged-- and neutral--kaon interactions in hydrogen, including as well a (brief) description of the problems left open by past experiments, and of the improvements DA$Φ$NE can be expected to offer over them. Interactions in deuterium and other light nuclei will be only brief

Tomas Blazek, Stuart Raby, Stefan Pokorski

We evaluate the finite 1-loop threshold corrections, proportional to $tanβ$, to the down quark mass matrix. These result in corrections to down quark masses and to Cabibbo-Kobayashi-Maskawa [CKM] matrix elements. The corrections to CKM matrix elements are the novel feature of this paper. For grand unified theories with large $\tanβ$ these corrections may sig

Nir J. Shaviv

Most cosmological models for gamma-ray bursts invoke the production of a ``fireball'' in a compact region, as indicated by the short time variability of the observed GRBs. The high density of $e^+e^-$ pairs in such fireballs inevitably makes them opaque to gamma-rays and requires the gamma-ray emission to take place only after the fireball has expand

John C. Baez

A spin network is a generalization of a knot or link: a graph embedded in space, with edges labelled by representations of a Lie group, and vertices labelled by intertwining operators. Such objects play an important role in 3-dimensional topological quantum field theory, functional integration on the space A/G of connections modulo gauge transformations, and

V. N. Prigodin, N. Taniguchi, A. Kudrolli, V. Kidambi

The correlation between the values of wavefunctions at two different spatial points is examined for chaotic systems with time-reversal symmetry. Employing a supermatrix method, we find that there exist long-range Friedel oscillations of the wave function density for a given eigenstate, although the background wavefunction density fluctuates strongly. We show

Martin Cederwall, Alexander von Gussich, Per Sundell

We study deformations of closed string theory by primary fields of conformal weight $(1,1)$, using conformal techniques on the complex plane. A canonical surface integral formalism for computing commutators in a non-holomorphic theory is constructed, and explicit formulæfor deformations of operators are given. We identify the unique regularization of the ari

S. Typel, G. Baur

We study the corrections of first order electromagnetic excitation due to higher order electromagnetic interactions. An effective operator is introduced which takes these effects into account in the sudden approximation. Evaluating the matrix-elements of this operator between the relevant states corrections to the first order result are obtained in a simple

Andreas Giesekus

Dynamical correlation functions for temperature T=0 are calculated for a Hubbard chain with infinite on-site repulsion. This chain contains three sites per unit cell and has a known resonating-valence-bond ground state for a filling of 2 particles per unit cell. A finite system of 24 sites is studied numerically. The recursion method is applied and results f

P. M. Nadolsky, S. M. Troshin, N. E. Tyurin

We emphasize that recently observed regularities in hadron interactions and deep-inelastic scattering are of preasymptotic nature and it is impossible to make conclusions on the true asymptotic behavior of observables without unitarization procedure. Unitarization is important and changes scattering picture drastically.

F. Seno, A. L. Stella, C. Vanderzande

By a new type of finite size scaling analysis on the square lattice, and by renormalization group calculations on hierarchical lattices we investigate the effects of dilution on optimal undirected self-avoiding paths in a random environment. The behaviour of the optimal paths remains the same as for directed paths in undiluted medium, as long as forbidden bo

Malte Henkel, Enzo Orlandini, Gunter M. Schütz

Time-dependent correlation functions of (unstable) particles undergoing biased or unbiased diffusion, coagulation and annihilation are calculated. This is achieved by similarity transformations between different stochastic models and between stochastic and soluble {\em non-stochastic} models. The results agree with experiments on one-dimensional annihilation

Arnd Leike

Analytical formulae for triple differential distributions ${\rm d}^3σ/({\rm d}\cosθ{\rm d}s_1{\rm d}s_2)$ in the neutral current process $e^+e^-\rightarrow f_1\bar f_1 f_2\bar f_2$ are given. They allow to obtain angular distributions, rapidity distributions and transversal momentum distributions of one fermion pair by only two numerical integrations. Cuts c

P. Coleman, A. J. Schofield

We adapt strong-coupling methods first used in the one-channel Kondo model to develop a simple description of the spin-$1\over 2$ two-channel Kondo model with channel anisotropy. Our method exploits spin-charge decoupling to develop a compactified Hamiltonian that describes the spin excitations. The structure of the fixed-point Hamiltonian and quasiparticle

Yu-kui Zhou

The restricted SOS model of Andrews, Baxter and Forrester has been studied. The finite size corrections to the eigenvalue spectra of the transfer matrix of the model with a more general crossing parameter have been calculated. Therefore the conformal weights and the central charges of the non-unitary or unitary minimal conformal field have been extracted fro

Steven Carlip

I investigate the relationship between the phase space path integral in (2+1)-dimensional gravity and the canonical quantization of the corresponding reduced phase space in the York time slicing. I demonstrate the equivalence of these two approaches, and discuss some subtleties in the definition of the path integral necessary to prove this equivalence.

T. Jacobs, S. Sridhar, C. T. Rieck, K. Scharnberg

We present measurements of the microwave surface resistance Rs and the penetration depth lambda of YBCO:123 crystals. At low T obeys lambda(T) a polynomial behavior, while Rs displays a characteristic non-monotonic T-dependence. A detailed comparison of the experimental data is made to a model of d-wave superconductivity which includes both elastic and inela

T. Jacobs, Balam A. Willemsen, S. Sridhar, R. Nagarajan

We report measurements of the microwave surface impedance of the borocarbide family of superconductors LnNi2B2C (Ln=Y, Er, Tm, Ho). The experiments enable direct measurements of the superfluid density, and are particularly sensitive to the influence of magnetic pairbreaking. In HoNi2B2C the antiferromagnetic transition is clearly observed at zero field, and

Chongying Dong, Haisheng Li, Geoffrey Mason

For the moonshine module $V^{\natural},$ whose automorphism is the Monster ${\Bbb M},$ We show how to give a uniform existence proof for irreducible $g$-twisted modules for elements of type $2A,$ $2B$ and $4A$ in ${\Bbb M}.$ The most interesting of these is the twisted sector $V^{\natural}(2A),$ whose automorphism group is essentially the centralizer of $2A$

Eugene Stern

The level 1 highest weight modules of the quantum affine algebra $U_q(\widehat{\frak{sl}}_n)$ can be described as spaces of certain semi-infinite wedges. Using a $q$-antisymmetrization procedure, these semi-infinite wedges can be realized inside an infinite tensor product of evaluation modules. This realization gives rise to simple descriptions of vertex ope

Jan F. van Diejen

We discuss the simultaneous diagonalization of a family of commuting difference operators by Koornwinder's multivariable generalization of the Askey-Wilson polynomials. The operators constitute a complete set of quantum integrals for a difference version of the $n$-particle quantum Calogero-Sutherland system related to the root system $BC_n$.

A. W. Schreiber, R. Rosenfelder, C. Alexandrou

We extend the polaron variational treatment previously developed for the propagator to the case where one nucleon and $n$ external mesons are present. Using the particle representation of the scalar Wick-Cutkosky model this is done in lowest order of an expansion of the exact action around a retarded quadratic trial action. In particular, we evaluate the for

L. Faddeev

It is shown that the generators of two discrete Heisenberg-Weyl groups with irrational rotation numbers $θ$ and $-1/ θ$ generate the whole algebra $\cal B$ of bounded operators on $L_2(\bf R)$. The natural action of the modular group in $\cal B$ is implied. Applications to dynamical algebras appearing in lattice regularization and some duality principles are

Malgorzata Klimek, Jerzy Lukierski

We describe the generators of kappa-conformal transformations, leaving invariant the kappa-deformed d'Alembert equation. In such a way one obtains the conformal extension of the off-shell spin zero realization of kappa-deformed Poincare algebra. Finally the algebraic structure of kappa-deformed conformal algebra is discussed.

Hyeon-Min Johng, Hak-Soo Shin, Kwang-Sup Soh

Two-dimensional dilaton gravity coupled to a Klein-Gordon matter field with a quartic interaction term is considered. The theory has a classical solution which exhibits black hole formation by a soliton. The geometry of black hole induced by a soliton is investigated.

Michael B. Green

A D-instanton is a space-time event associated with world-sheet boundaries that contributes non-perturbative effects of order $e^{-const/κ}$ to closed-string amplitudes. Some properties of a gas of D-instantons are discussed in this paper.

Yang Lu, R. D. Amado

We use classical or large Nc QCD to describe the mesons (pion, rho, omega) coming from proton-antiproton annihilation at rest as classical fields, which we then quantize as coherent states. This treatment gives a nearly parameter free account of the pion branching ratios in annihilation.

V. V. Vereshagin, A. N. Manashov, S. G. Sherman, U. Bohnert

This is the first of a series of papers on a consistent model independent analysis of the complete experimental information on the reaction $πN \rightarrow ππN$ at pion momenta up to 500 MeV/c. The paper summarizes the theoretical approach and details of the computational procedure. The complete database on total cross sections in 5 $ππN$ channels is given t