December 1994 arXiv papers — page 5

T. Buchert

A complete family of statistical descriptors for the morphology of large--scale structure based on Minkowski--Functionals is presented. These robust and significant measures can be used to characterize the local and global morphology of spatial patterns formed by a coverage of point sets which represent galaxy samples. Basic properties of these measures are

Daniel Z. Freedman, Ramzi R. Khuri

We display continuous families of SU(2) vector potentials $A_i^a(x)$ in 3 space dimensions which generate the same magnetic field $B^{ai}(x)$ (with det $B\neq 0$). These Wu-Yang families are obtained from the Einstein equation $R_{ij}=-2G_{ij}$ derived recently via a local map of the gauge field system into a spatial geometry with $2$-tensor $G_{ij}=B^a{}_i

L. Hlavaty

Extension of the braid relations to the multiple braided tensor product of algebras that can be used for quantization of nonultralocal models is presented. The Yang--Baxter--type consistency conditions as well as conditions for the existence of the multiple coproduct (monodromy matrix), which can be used for construction of the commuting subalgebra, are give

G. G. Hartwell, P. S. Howe

A family of harmonic superspaces associated with four-dimensional spacetime is described. Some applications to supersymmetric field theories, including supergravity, are given.

A. Girlando, A. Painelli, M. Ardoino, C. Bellitto

The spectroscopic effects of electron-phonon coupling in mixed-valence chlorine-bridged Pt chains complexes are investigated through a parallel infrared and Raman study of three compounds with decreasing Pt-Pt distance along the chain. The e-ph interaction is analyzed in terms of the Herzberg-Teller coupling scheme. We take into account the quadratic term an

Ikuo Ichinose, Yuji Satoh

Thermodynamics of scalar fields is investigated in three dimensional black hole backgrounds in two approaches. One is mode expansion and direct computation of the partition sum, and the other is the Euclidean path integral approach. We obtain a number of exact results, for example, mode functions, Hartle-Hawking Green functions on the black holes, Green func

V. M. Manuilov

It is known that a continuous family of compact operators can be diagonalized pointwise. One can consider this fact as a possibility of diagonalization of the compact operators in Hilbert modules over a commutative W*-algebra. The aim of the present paper is to generalize this fact for a finite W*-algebra $A$ not necessarily commutative. We prove that for a

M. Buballa

Generalizing a recent convolution model of the nucleon which explicitly conserves charge and momentum we reexamine the influence of an enhanced pion field in nuclei on EMC and Drell-Yan ratios. Due to wave function renormalization constants the effect is more than 50% smaller than predicted by the standard pion excess model. In particular there is no discrep

B. G. Giraud, W-h. Ma, R. Peschanski

Linear rate equations are used to describe the cascading decay of an initial heavy cluster into fragments. This representation is based upon a triangular matrix of transition rates. We expand the state vector of mass multiplicities, which describes the process, into the biorthonormal basis of eigenmodes provided by the triangular matrix. When the transition

Tae-Sun Park, Dong-Pil Min, Mannque Rho

We calculate the cross-section for the thermal $n+p\rightarrow d+γ$ process in chiral perturbation theory to next-to-next-to-leading order using heavy-fermion formalism. The exchange current correction is found to be $(4.5\pm 0.3)~\%$ in amplitude and the chiral perturbation at one-loop order gives the cross section $σ_{th}^{np}=(334\pm 2)\ {\mbox mb}$ which

Ramzi R. Khuri

We present two-parameter solutions of the low-energy four-dimensional heterotic string which in the extremal limit reduce to supersymmetric monopole, string and domain wall solutions. The effective scalar coupling to the Maxwell field, $e^{-αϕ} F_{μν} F^{μν}$, gives rise to a new string black hole with $α= \sqrt{3}$, in contrast to the pure dilaton black hol

S. Kanemura, H. -T. Sato

We discuss a phase structure of chiral symmetry breaking in the Gross-Neveu model at finite temperature, density and constant curvature. The effective potential is evaluated in the leading order of the $1/N$-expansion and in a weak curvature approximation. The third order critical line is found on the critical surface in the parameter space of temperature, c

C. Emmrich, A. Weinstein

Although the WKB approximation for multicomponent systems has been intensively studied in the literature, its geometric and global aspects are much less well understood than in the scalar case. In this paper we give a completely geometric derivation of the transport equation, without using local sections and without assuming complete diagonalizability of the

J. P. Garrahan, L. M. Kruczenski, C. L. Schat, D. R. Bes

The Becchi-Rouet-Stora-Tyutin (BRST) method is applied to the quantization of the solitons of the non-linear $O(3)$ model in $2+1$ dimensions. We show that this method allows for a simple and systematic treatment of zero-modes with a non-commuting algebra. We obtain the expression of the BRST hamiltonian and show that the residual interaction can be perturba

Martin Lavelle, David McMullan

Gauge fixing and the observable fields for both abelian and non-abelian gauge theories with spontaneous breaking of gauge symmetry are studied. We explicitly show that it is possible to globally fix the gauge in the broken sector and hence construct physical fields even in the non-abelian theory. We predict that any high temperature restoration of gauge symm

F. Lenz, E. J. Moniz, M. Thies

A comparative dynamical study of axial gauge QED and QCD is presented. Elementary excitations associated with particular field configurations are investigated. Gluonic excitations analogous to linearly polarized photons are shown to acquire infinite energy. Suppression of this class of excitations in QCD results from quantization of the chromelectric flux an

Marc Henneaux

The antifield-BRST formalism and the various cohomologies associated with it are surveyed and illustrated in the context of Yang-Mills gauge theory. In particular, the central role played by the Koszul-Tate resolution and its relation to the characteristic cohomology are stressed.

L. L. Salcedo, E. Ruiz Arriola

We use the $ζ$-function regularization and an integral representation of the complex power of a pseudo differential operator, to give an unambiguous definition of the determinant of the Dirac operator. We bring this definition to a workable form by making use of an asymmetric Wigner representation. The expression so obtained is amenable to several treatments

Jin Bai-Qi, Ma Zhong-Qi

The quantum Clebsch-Gordan coefficients and the explicit form of the $\breve{R}_{q}$ matrix related with the minimal representation of the quantum enveloping algebra $U_{q}E_{7}$ are calculated in this paper.

Steven B. Giddings

These lectures give a pedagogical review of dilaton gravity, Hawking radiation, the black hole information problem, and black hole pair creation. (Lectures presented at the 1994 Trieste Summer School in High Energy Physics and Cosmology)

Chungsik Song, Su Houng Lee, Che Ming Ko

The pion electromagnetic form factor at finite temperature is studied using an effective chiral lagrangian that includes explicitly vector mesons. We find that in the time-like region around the rho meson resonance it decreases with increasing temperature and leads to a suppression of dilepton production from pion-pion annihilation in a hot hadronic matter.

Loyal Durand, Bernd A. Kniehl, Kurt Riesselmann

We calculate the dominant ${\rm O}\left(G_F^2M_H^4\right)$ two-loop electroweak corrections to the fermi\-onic decay widths of a heavy Higgs boson in the Standard Model. Use of the Goldstone-boson equivalence theorem reduces the problem to one involving only the physical Higgs boson $H$ and the Goldstone bosons $w^\pm$ and $z$ of the unbroken theory. The two

Y. Koike, K. Tanaka

We investigate the $Q^{2}$-evolution of the chiral-odd spin-dependent parton distribution $h_{L}(x, Q^{2})$ relevant for the polarized Drell-Yan processes. The results are obtained in the leading logarithmic order in the framework of the renormalization group and the standard QCD perturbation theory. We calculate the anomalous dimension matrix for the twist-

G. Schierholz

We investigate the dependence of the CP^3 model and of the SU(2) Yang-Mills theory on the vacuum angle theta. The CP^3 model exhibits a first order deconfining phase transition in theta. The critical value of theta runs from pi in the strong coupling limit towards zero as beta is taken to infinity. Qualitatively the same behavior is found in the SU(2) Yang-M

M, :, Plagge, D. Talkenberger

We report on our work on the SU(2)_L x SU(2)_R symmetric Higgs Yukawa Model with mirror fermion action. Our model describes a fermion Higgs system in the limit of vanishing gauge coupling. Setting the bare Yukawa coupling of the mirror fermions G_χto zero, we want to determine the triviality bounds on the renormalized Yukawa coupling of the fermions G_{Rψ} a

James Sexton, Donald Weingarten

We describe a systematic expansion for full QCD. The leading term in the expansion gives the valence approximation. The expansion reproduces full QCD if an infinite number of higher terms are included.

Bernd Dahmen

A recently proposed method for a strong coupling analysis of scattering phenomena in hamiltonian lattice field theories is applied to the $\SU2$ Yang-Mills model in $(2+1)$ dimensions. The calculation is performed up to second order in the hopping parameter. All relevant quantities that characterize the collision between the lightest glueballs in the elastic

M. Iwasaki

We have studied open charm production in $γγ$ collisions with the TOPAZ detector at the TRISTAN $e^{+}e^{-}$ collider. In this study, charm quarks were identified by electrons (and positrons) from semi-leptonic decays of charmed hadrons. The data corresponded to an integrated luminosity of 95.3 pb$^{-1}$ at a center-of-mass energy of 58 GeV. The results are

Fjodor V. ~Kusmartsev, Eckehard W. ~Mielke, Yuri N. ~Obukhov, Franz E. ~Schunck

Various scenarios of the initial inflation of the universe are distinguished by the choice of a scalar field {\em potential} $U(ϕ)$ which simulates a {\it temporarily} non--vanishing {\em cosmological term}. Our new method, which involves a reparametrization in terms of the Hubble expansion parameter $H$, provides a classification of allowed inflationary pot

A. López--Pinto, A. Tiemblo, R. Tresguerres

We present a general framework to include ordinary fermionic matter in the metric--affine gauge theories of gravity. It is based on a nonlinear gauge realization of the affine group, with the Lorentz group as the classification subgroup of the matter and gravitational fields.

Piotr T. Chrusciel, Nikolai S. Nadirashvili

We show that all Majumdar--Papapetrou electrovacuum space--times with a non--empty black hole region and with a non--singular domain of outer communications are the standard Majumdar--Papapetrou space--times.

Agha Afsar Ali, Deepak Dhar

We study the abelian sandpile model on decorated one dimensional chains. We determine the structure and the asymptotic form of distribution of avalanche-sizes in these models, and show that these differ qualitatively from the behavior on a simple linear chain. We find that the probability distribution of the total number of topplings $s$ on a finite system o

M. Jarrell, J. K. Freericks, Th. Pruschk

A Monte Carlo-maximum entropy calculation of the optical conductivity of the infinite-dimensional Hubbard model is presented. We show that the optical conductivity displays the anomalies found in the cuprate superconductors, including a Drude width which grows linearly with temperature, a Drude weight which grows linearly with doping, and a temperature and d

S. Franz, M. Ney-Nifle

We study the correlations between two equilibrium states of SK spin glasses at different temperatures or magnetic fields. The question, presiously investigated by Kondor and Kondor and Végsö, is approached here constraining two copies of the same system at different external parameters to have a fixed overlap. We find that imposing an overlap different from

R. Podgornik, S. Svetina, B. Žekš

The issue of different parameterizations of the axisymmetric vesicle shape addressed by Hu Jian-Guo and Ou-Yang Zhong-Can [ Phys.Rev. E {\bf 47} (1993) 461 ] is reassesed, especially as it transpires through the corresponding Euler - Lagrange equations of the associated elastic energy functional. It is argued that for regular, smooth contours of vesicles wit

Kenneth K. Young

The DUMAND-II detector will search for astronomical sources of high energy neutrinos. Successful deployment of the basic infrastructure, including the shore cable, the underwater junction box, and an environmental module was accomplished in December, 1993. One optical module string was also deployed and operated, logging data for about 10 hours. The underwat

R. J. Rivers, T. S. Evans

We shall show that the density of defects produced at a second-order phase transition is determined by the correlation length of the fields. This is true both for defects appearing in the Ginzburg regime and for defects produced at a quench, when the Ginzburg regime is irrelevant. (Invited lectures given by R.J.R. to the Nato Advanced Study Institute and Eur

V. Antonuccio-Delogu

We reconsider the problem of the origin of Low-Surface-Brightness (LSB) galaxies within the standard Cold Dark Matter (CDM) cosmological model ($Ω=1, h=0.5$). Taking into account the effect of substructure on the collapse times of low overdensity peaks, we show that the abundance of these peaks is larger than previously expected because of the dragging cause

M. Shaw, D. Axon, R. Probst, I. Gatley

Multicolour near IR photometry for a sample of 32 large barred spiral galaxies is presented. By applying ellipse fitting techniques, we identify significant isophote twists with respect to the primary bar axis in the nuclear regions of $\sim$70 \%\ of the sample. These twists are identified in galaxies as late as SBbc and are clearly distinguishable from spi

R. A. Battye, E. P. S. Shellard

We show that it is possible to evolve a network of global strings numerically including the effects of radiative backreaction, using the renormalised equations for the Kalb-Ramond action. We calculate radiative corrections to the equations of motion and deduce the effect on a network of global strings. We also discuss the implications of this work for the co

M. Kawasaki, T. Moroi

We investigate the electromagnetic cascade initiated by injection of very high energy photons in the early Universe and calculate the cascade spectrum by solving a set of Boltzmann equations numerically. In the calculation we take account of Compton scattering off the background electrons and pair creation off the background nucleons as well as photon-photon

Craig J. Hogan

Scale-invariant fluctuations and cold dark matter could originate from two different modes of a single scalar field, fluctuations from massless Goldstone oscillations and matter from massive Higgs modes. Matching the fluctuations and dark matter density observed requires a heavy scale ($ϕ_0\approx 10^{16}$GeV) for the potential minimum and an extremely small

A. Carlini, D. H. Coule, D. M. Solomons

We consider the quantum analogues of wormholes obtained by Carlini and Mijić (CM), who analytically continued closed universe models. To obtain wormholes when the strong energy condition ($γ>2/3$) is satisfied, we are able to simplify the Wheeler-DeWitt (WDW) equation by using an equivalent scalar potential which is a function of the scale factor. Such wormh

P. G. Grinevich, M. U. Schmidt

Flows on the moduli space of the algebraic Riemann surfaces, preserving the periods of the corresponding solutions of the soliton equations are studied. We show that these flows are gradient with respect to some indefinite symmetric flat metric arising in the Hamiltonian theory of the Whitham equations. The functions generating these flows are conserved quan

M. J. Vicente-Vacas, M. Kh. Khankhasayev, S. G. Mashnik

A cascade model has been developed to study pion induced multichannel reactions (quasielastic, SCX, DCX, absorption and pion production) at pion energies above 0.5 GeV. Special attention has been paid to pion double charge exchange. Pion production is a determinant feature in the high energy pion nucleus reactions, and the DCX signal not related to pion prod

Edwin Langmann, Jouko Mickelsson

An elementary derivation of the chiral gauge anomaly in all even dimensions is given in terms of noncommutative traces of pseudo-differential operators.

Eugene Kogan, Moshe Kaveh

In our previous publication [Kogan et al, Phys. Rev. {\bf 48}, 9404 (1993)] we considered the issue of statistics of radiation diffusively propagating in a disordered medium. The consideration was in the framework of diagrammatic techniques and a new representation for the intensity distribution function in terms of connected diagrams only was proposed. Here

Yuliy Baryshnikov

Retracted temporarily to fix some erratic things.

Rajan Gupta

This talk contains an analysis of quenched chiral perturbation theory and its consequences. The chiral behavior of a number of quantities such as the pion mass $m_π^2$, the Bernard-Golterman ratios $R$ and $χ$, the masses of nucleons, and the kaon B-parameter are examined to see if the singular terms induced by the additional Goldstone boson,$η'$, are vi

Kenji Kajiwara, Yasuhiro Ohta, Junkichi Satsuma

The discrete Painlevé III equation is investigated based on the bilinear formalism. It is shown that it admits the solutions expressed by the Casorati determinant whose entries are given by the discrete Bessel function. Moreover, based on the observation that these discrete Bessel functions are transformed to the $q$-Bessel functions by a simple variable tra

Shin-ichi Tadaki

Periodicity and relaxation are investigated for the trajectories of the states in cylindrical linear cellular automata. The time evolutions are described with matrices. The eigenvalue analysis is applied to obtain the maximum values of period and relaxation. The translational invariance suppresses the maximum period and relaxation.

F. Navarra, U. Ornik

The equation of state of the linear sigma model in the mean field approximation is used as input in a relativistic hydrodynamical numerical routine. Longitudinal and transverse energy distributions are calculated and compared with those obtained from the QHD-I equation of state.

V. V. Flambaum, O. K. Vorov

Manifestations of P-,T-odd weak interaction between nucleons in nucleus are considered. Renormalization of this interaction due to residual strong interaction is studied. Mean squared matrix elements of P-,T-odd weak interaction between compound states are calculated. Correlators between P-,T-odd and P-odd, T-even weak interaction matrix elements between com

Dinghui Lu, Shashikant C. Phatak, Rubin H. Landau

We apply the chiral color dielectric model to low- and medium-energy scattering within the coupled $π$N and $πΔ$ system. Dynamic baryon states in which quarks are confined by the scalar color-dielectric field are constructed in Fock space. Spurious motion of the center of mass is eliminated by constructing momentum eigenstates via a Peierls-Yoccoz projection

Shmuel Lifsches, Saharon Shelah

The monadic second-order theory of trees allows quantification over elements and over arbitrary subsets. We classify the class of trees with respect to the question: does a tree T have definable Skolem functions (by a monadic formula with parameters)? This continues [LiSh539] where the question was asked only with respect to choice functions. Here we define

Saharon Shelah, Simon Thomas

A group G that is not finitely generated can be written as the union of a chain of proper subgroups. The cofinality spectrum of G, written CF(S), is the set of regular cardinals lambda such that G can be expressed as the union of a chain of lambda proper subgroups. The cofinality of G, written c(G), is the least element of CF(G). We show that it is consisten

Saharon Shelah

We deal with consistency results for the existence of universal models in natural classes of models (more exactly--a somewhat weaker version). We apply a result on quite general family to T_feq and to the class of triangle-free graphs.

Mikhail S. Plyushchay, Alexander V. Razumov

The relationship between the Dirac and reduced phase space quantizations is investigated for spin models belonging to the class of Hamiltonian systems having no gauge conditions. It is traced out that the two quantization methods may give similar, or essentially different physical results, and, moreover, it is shown that there is a class of constrained syste

Zhong Tang, David Finkelstein

We construct a relativistically covariant symmetry of QED. Previous local and nonlocal symmetries are special cases. This generalized symmetry need not be nilpotent, but nilpotency can be arranged with an auxiliary field and a certain condition. The Noether charge generating the symmetry transformation is obtained, and it imposes a constraint on the physical

Michele Bourdeau

N=2 supersymmetric field theories in two dimensions have been extensively studied in the last few years. Many of their properties can be determined along the whole renormalization group flow, like their coupling dependence and soliton spectra. We discuss here several models which can be solved completely, when the number of superfields is taken to be large,

Khazret S. Nirov

For a wide class of mechanical systems, invariant under gauge transformations with higher (arbitrary) order time derivatives of gauge parameters, the equivalence of Lagrangian and Hamiltonian BRST formalisms is proved. It is shown that the Ostrogradsky formalism establishes the natural rules to relate the BFV ghost canonical pairs with the ghosts and antigho

Noureddine Mohammedi

A Symmetry between bosonic coordinates and some Grassmannian-type coordinates is presented. Commuting two of these Grassmannian-type variables results in an arbitrary phase (not just a minus sign). This symmetry is also realised at the level of the field theory.

I. L. Buchbinder, V. A. Krykhtin, V. D. Pershin

We consider the theory of open bosonic string in massive background fields. The general structure of renormalization is investigated. A general covariant action for a string in background fields of the first massive level is suggested and its symmetries are described. Equations of motion for the background fields are obtained by demanding that the renormaliz

Thomas Banks

Trieste Spring School Lectures describing the author's opinions about black hole evaporation and information loss. The remnant, or cornucopion scenario for the endpoint of Hawking evaporation is described in detail. In this picture information can be lost to the original asymptotic observer without violating the rules of quantum mechanics, because a blac

Bernd Kuckert

We give an algebraic proof of the spin-statistics connection for the parabosonic and parafermionic quantum topological charges of a theory of local observables with a modular PCT-symmetry. The argument avoids the use of the spinor calculus and also works in 1+2 dimensions. It is expected to be a progress towards a general spin-statistics theorem including al

Sergei Lukyanov, Yaroslav Pugai

These lectures were prepared to be presented at A.A. Belavin seminar on CFT at Landau Institute for Theoretical Physics. We review bosonization of CFT and show how it can be applied to the studying of representations of Zamolodchikov-Faddeev (ZF) algebras. In the bosonic construction we obtain explicit realization of chiral vertex operators interpolating bet

L. A. Ferreira, J. L. Miramontes, J. Sanchez Guillen

We consider the Hamiltonian reduction of the two-loop Wess-Zumino-Novikov-Witten model (WZNW) based on an untwisted affine Kac-Moody algebra $\cgh$. The resulting reduced models, called {\em Generalized Non-Abelian Conformal Affine Toda (G-CAT)}, are conformally invariant and a wide class of them possesses soliton solutions; these models constitute non-abeli

M. Block

Both the light hypernucleus ${}_Λ{\rm H}^4$ and the nucleus ${\rm He}^4$ have spin 0. The ratio $R$ of the electron to muon rates for the pure Fermi transitions \begin{equation} R=\frac{Γ\left({}_Λ{\rm H}^4\rightarrow {\rm e}^- + \bar ν+{\rm He}^4\right)} {Γ\left({}_Λ{\rm H}^4\rightarrow μ^- + \bar ν+{\rm He}^4\right)} \end{equation} is a sensitive measure o

R. Arnowitt, Pran Nath

The $b\rightarrow s+ γ$ decay is a powerful tool for testing models of new physics because the new physics diagrams enter in the same loop order as the Standard Model ones. The current experimental and theoretical status of this decay is reviewed. Predictions based on the minimal supergravity model (MSGM) in the leading order (LO) are discussed. It is shown

M. M. Block, F. Halzen, B. Margolis, A. R. White

Utilizing the most recent experimental data, we reanalyze high energy \pbar p and pp data, using two distinct (and {\em dissimilar}) analysis techniques: (1) asymptotic amplitude analysis, under the assumption that we have reached `asymptopia', and (2) an eikonal model whose amplitudes are designed to mimic real QCD amplitudes. The former gives strong ev

Andrei L. Kataev, Valery V. Starshenko

We present the estimates of the five-loop QED corrections to the muon anomaly using the scheme-invariant approaches and demonstrate that they are in good agreement with the results of exact calculations of the corresponding tenth-order diagrams supplemented by the additional guess about the values of the non-calculated contributions.

V. Pleitez

We study two 3-3-1 models with i) five (four) charge 2/3 ($-1/3$) quarks and, ii) four (five) charge 2/3 ($-1/3$) quarks and a vector-like third generation. Possibilities beyond these models are also briefly considered.

C. Bertulani, L. Mornas, U. Ornik

We present a model of coherent Bremsstrahlung emission from the compression phase of relativistic heavy ion collisions based on a hydrodynamical description of the collision process. The decceleration of the matter through a shock front, calculated in 1-D relativistic dissipative hydrodynamics, is at the origin of a copious Bremsstrahlung emission. The inter

Dong-Pil Min, Yongseok Oh, Byung-Yoon Park, Mannque Rho

We review recent development on combining heavy-quark symmetry and chiral symmetry in the skyrmion structure of the baryons containing one or more heavy quarks, c (charmed) and b (bottom). We describe two approaches: One going from the chiral symmetry regime of light quarks to the heavy-quark symmetry regime which will be referred to as ``bottom-up" appr

F. E. Close, P. R. Page

Decay widths, branching ratios and production dynamics of some recently discovered $J^{PC} = 1^{-+}, 0^{-+}$,$1^{--}$ and $2^{-+}$ mesons are found to be in remarkable agreement with the predicted properties of hybrid mesons. We propose tests for this new dynamics, emphasise the critical role of $πb_1$ or $πh_1$ decay channels in discriminating hybrids from

S. Y. Choi

We study possible deviations from the standard model in the reaction $γe\rightarrow Ze$ at a 500 GeV $e^+e^-$ collider. As a photon source we use a laser backscattered photon beam. We investigate the most general $γZγ$ and $γZZ$ vertices including operators up to energy-dimension-six which are Lorentz invariant. These vertices require four extra parameters;

C. G. Boyd, Z. Guralnik, M. Schmaltz, F. J. Vegas

We calculate the $α_s$ corrections to the form factors which parameterize the hadronic tensor relevant for inclusive semileptonic $B \rightarrow X τ\barν_τ$ and $Λ_b \rightarrow X τ\barν_τ$ decays. We apply our results to the double differential decay rates for the decays of $B$ mesons and polarized $Λ_b$ baryons to polarized $τ$ leptons, presenting them in

P. Lacock, A. McKerrell, C. Michael, I. M. Stopher

We study operators to create hadronic states made of light quarks in quenched lattice gauge theory. We construct non-local gauge-invariant operators which provide information about the spatial extent of the ground state and excited states. The efficiency of the operators is shown by looking at the wave function of the first excited state, which has a node as

J. Julve, A. López--Pinto, A. Tiemblo, R. Tresguerres

We present a general scheme for the nonlinear gauge realizations of spacetime groups on coset spaces of the groups considered. In order to show the relevance of the method for the rigorous treatment of the translations in gravitational gauge theories, we apply it in particular to the affine group. This is an illustration of the family of spacetime symmetries

M. Cristina Marchetti, David R. Nelson

A novel two-sided Bitter decoration technique was recently employed by Yao et al. to study the structure of the magnetic vortex array in high-temperature superconductors. Here we discuss the analysis of such experiments. We show that two-sided decorations can be used to infer {\it quantitative} information about the bulk properties of flux arrays, and discus

Emilio Artacho, Arturo Lizon-Nordstrom, Felix Yndurain

The problem of the geometry of interstitial oxygen in silicon is settled by proper consideration of the quantum delocalization of the oxygen atom around the bond-center position. The calculated infrared absorption spectrum accounts for the 517 and 1136 cm$^{-1}$ bands in their position, character, and isotope shifts. The asymmetric lineshape of the 517 cm$^{

Alain Comtet, Stefan Mashkevich, Stéphane Ouvry

The spectrum of a charged particle coupled to Aharonov-Bohm/anyon gauge fields displays a nonanalytic behavior in the coupling constant. Within perturbation theory, this gives rise to certain singularities which can be handled by adding a repulsive contact term to the Hamiltonian. We discuss the case of smeared flux tubes with an arbitrary profile and show t

T. Blum, M. A. Moore

The recent discovery that some of the coefficients of the viscosity tensor are negative is shown to invalidate the hydrodynamic approach to the vortex liquid phase of a type-II superconductor. A satisfactory theory requires retention of all the spatial gradients of the velocities or electric fields and not just the first derivatives, as assumed in a hydrodyn

Jean DESBOIS, Cyril FURTLEHNER, Stéphane OUVRY, Division de Physique Théorique

One considers the effect of disorder on the 2-dimensional density of states of an electron in a constant magnetic field superposed onto a Poissonnian random distribution of point vortices. If one restricts the electron Hilbert space to the lowest Landau level of the total average magnetic field, the random magnetic impurity problem is mapped onto a contact $

D. Belitz, T. R. Kirkpatrick

An order parameter description of the Anderson-Mott transition (AMT) is given. We first derive an order parameter field theory for the AMT, and then present a mean-field solution. It is shown that the mean-field critical exponents are exact above the upper critical dimension. Renormalization group methods are then used to show that a random-field like term i

Timothy Andrew Cartwright, Michael R. Brent

Infants face the difficult problem of segmenting continuous speech into words without the benefit of a fully developed lexicon. Several sources of information in speech might help infants solve this problem, including prosody, semantic correlations and phonotactics. Research to date has focused on determining to which of these sources infants might be sensit

Ronnie Mainieri

Cycle expansions are an efficient scheme for computing the properties of chaotic systems. When enumerating the orbits for a cycle expansion not all orbits that one would expect at first are present --- some are pruned. This pruning leads to convergence difficulties when computing properties of chaotic systems. In numerical schemes, I show that pruning reduce

P. Bhattacharjee, G. Sigl

Cosmic rays with energies exceeding $10^{20}\eV$ have been detected. The origin of these highest energy cosmic rays remains unknown. Established astrophysical acceleration mechanisms encounter severe difficulties in accelerating particles to these energies. Alternative scenarios where these particles are created by the decay of cosmic topological defects hav

M. Prisznyak, B. Lukacs, P. Levai

It is examined whether primordial top quarks from the Big Bang could survive under natural conditions till present days. Hybrid quark-neutron stars, with dense enough core to maintain the existence of top quarks, is discussed. In this paper only final states are investigated. Zero temperature quark-lepton matter is modelled as as a gas of non-interacting par

Matthias Bartelmann

The reliability of cluster lens reconstruction techniques based on weak lensing is studied in terms of the accuracy of their reproduction of the total cluster mass as a function of distance from the cluster center. To do so, a variety of reconstruction algorithms is applied to synthetic lensing data created using a sample of 60 numerically modeled clusters,

Lev Kofman

This contribution to the Proceedings is based on the talk given at the Conference on Birth of the Universe and Fundamental Physics, Rome, May 18-21, 1994. Some selected topics of the subject are reviewed: Models of Primordial Fluctuations; Reconstruction of the Cosmological Density Probability Distribution Function (PDF) from Cumulants; PDFs from the Zel&#39

M. V. Catalisano, A. Gimigliano

In this paper we find an algorithm which computes the Hilbert function of schemes $Z$ of "fat points" in $\PP3$ whose support lies on a rational normal cubic curve $C$. The algorithm shows that the maximality of the Hilbert function in degree $t$ is related to the existence of fixed curves (either $C$ itself or one of its secant lines) for the linear

R. A. Sharipov, A. B. Sukhov

We prove the algebraicity of smooth $CR$-mappings between algebraic Cauchy--Riemann manifolds. A generalization of separate algebraicity principle is established.

Alex Kasman

A new construction using finite dimensional dual grassmannians is developed to study rational and soliton solutions of the KP hierarchy. In the rational case, properties of the tau function which are equivalent to bispectrality of the associated wave function are identified. In particular, it is shown that there exists a bound on the degree of all time varia

Stephan Narison

We review the present status in the determination of the $accurate$ value of $α_s$ from $τ$-decays, where we discuss in detail the different sources of theoretical errors.

Jianming Zhang, Charles Gale

We use the Boltzmann-Uehling-Uhlenbeck model with a momentum-dependent nuclear mean field to simulate the dynamical evolution of heavy ion collisions. We re-examine the azimuthal anisotropy observable, proposed as sensitive to the equation of state of nuclear matter. We obtain that this sensitivity is maximal when the azimuthal anisotropy is calculated for n

J. Helgesson, J. Randrup

With a view towards implementation in microscopic transport simulations of heavy-ion collisions, the properties of spin-isospin modes are studied in nuclear matter consisting of nucleons and Delta isobars that interact by the exchange of pi and rho mesons. For a standard p-wave interaction and an effective g' short-range interaction, the dispersion relat

V. V. Flambaum, O. K. Vorov

Two-nucleon parity nonconserving (PNC) interaction induced by the single-particle PNC weak potential and the two-nucleon residual strong interaction is considered. An approximate analytical formula for this Induced PNC Interaction (IPNCI) between proton and neutron is derived ($Q({\bf r} {\bf σ}_{p} \times {\bf σ}_{n}) δ({\bf r}_{p}-{\bf r}_{n})$), and the i

Jonathan Huntley, Jay Jorgenson, Rolf Lundelius

We develop an asymptotic expansion of the spectral measures on a degenerating family of hyperbolic Riemann surfaces of finite volume. As an application of our results, we study the asymptotic behavior of weighted counting functions, which, if $M$ is compact, is defined for $w \geq 0$ and $T > 0$ by $$N_{M,w}(T) = \sum\limits_{λ_n \leq T}(T-λ_n)^w $$ where $\

T. Gannon, C. Jakovljevic, M. A. Walton

Dominant weight multiplicities of simple Lie groups are expressed in terms of the modular matrices of Wess-Zumino-Witten conformal field theories, and related objects. Symmetries of the modular matrices give rise to new relations among multiplicities. At least for some Lie groups, these new relations are strong enough to completely fix all multiplicities.