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June 1995 arXiv papers — page 6

Showing 501–600 of 1,161 papers

  1. Lior M. Burko, Amos Ori

    It has been recently suggested that the Non-symmetric Gravitational Theory (NGT) is free of black holes. Here, we study the linear version of NGT. We find that even with spherical symmetry the skew part of the metric is generally non-static. In addition, if the skew field is initially regular, it will remain regular everywhere and, in particular, at the hori

  2. Gil Zumbach, N. A. Modine, Efthimios Kaxiras

    We present a method for electronic structure calculations that retains all of the advantages of real space and addresses the inherent inefficiency of a regular grid, which has equal precision everywhere. The computations are carried out on a {\em regular} mesh in {\em curvilinear space}, which allows natural and efficient decomposition on parallel computers,

  3. Michael R. Geller, Giovanni Vignale

    We discuss a collective "breathing" mode of electrons with inverse-square-law interactions in a two-dimensional quantum dot and a perpendicular magnetic field.

  4. M. M. Fogler, B. I. Shklovskii

    It is known experimentally that at not very large filling factors $ν$ the quantum Hall conductivity peaks corresponding to the same Landau level number $N$ and two different spin orientations are well separated. These peaks occur at half-integer filling factors $ν= 2 N + 1/2$ and $ν= 2 N + 3/2$ so that the distance between them $δν$ is unity. As $ν$ increase

  5. Daniel Duffy, Adriana Moreo

    Comparing experimental data for high temperature cuprate superconductors with numerical results for electronic models, it is becoming apparent that a hopping along the plaquette diagonals has to be included to obtain a quantitative agreement. According to recent estimations the value of the diagonal hopping $t'$ appears to be material dependent. However,

  6. Peter Olsson

    The fully frustrated $XY$ model on a square lattice is studied by means of Monte Carlo simulations. A Kosterlitz-Thouless transition is found at $T_{\rm KT} \approx 0.446$, followed by an ordinary Ising transition at a slightly higher temperature, $T_c \approx 0.452$. The non-Ising exponents reported by others, are explained as a failure of finite size scali

  7. Jürgen König, Herbert Schoeller, Gerd Schön

    We study resonant tunneling through a quantum dot with one degenerate level in the presence of a strong Coulomb repulsion and a bosonic environment. Using a real-time approach we calculate the spectral density and the nonlinear current within a conserving approximation. The spectral density shows a multiplet of Kondo peaks split by the transport voltage and

  8. S. Malinowski

    In a time-reversal non-invariant system the entropy production, dS/dt, may be negative. Close to the critical point of medium it is positive: larger or smaller as compared with one above critical point depending on whether the transitions from lower states to higher states of the system are more (less) probable than the reverse transitions. PACS numbers: 05.

  9. Hisatoshi Yokoyama, Yoshio Kuramoto, Masao Ogata

    We give a brief review of recent developments by the variational Monte Carlo method, in addition to some new results. We discuss $t$-$J$-type models: the ordinary $t$-$J$ model in one and two dimensions, and the one-dimensional supersymmetric $t$-$J$ model with the long-range coupling of inverse square.

  10. J. H. Knapen, J. E. Beckman, C. H. Heller, I. Shlosman

    We present new high-resolution observations of the center of the late-type spiral M100 (NGC 4321) supplemented by 3D numerical modeling of stellar and gas dynamics, including star formation (SF). NIR imaging has revealed a stellar bar, previously inferred from optical and 21 cm observations, and an ovally-shaped ring-like structure in the plane of the disk.

  11. Brian Chaboyer, Yong --Cheol Kim

    The Yale stellar evolution code has been modified to use the OPAL equation of state tables (Rogers 1994). Stellar models and isochrones were constructed for low metallicity systems ($-2.8 \le [Fe/H] \le -0.6$). Above $M\sim 0.7\,\msun$, the isochrones are very similar to those which are constructed using an equation of state which includes the analytical Deb

  12. A. Bondal, D. Orlov

    A criterion for a functor between derived categories of coherent sheaves to be full and faithful is given. A semiorthogonal decomposition for the derived category of coherent sheaves on the intersection of two even dimensional quadrics is obtained. The behaviour of derived categories with respect to birational transformations is investigated. A theorem about

  13. Anu Venugopalan, R. Ghosh

    The measurements in the optical test of quantum Zeno effect [Itano et al. Phys. Rev. A\underbar{41} (1990) 2295) are analyzed using the environment-induced decoherence theory, where the spontaneous emission lifetime of the relevant level emerges as the 'decoherence time'. The implication of this finite decoherence time in setting a fundamental limit

  14. Sudhansu S. Mandal, V. Ravishankar

    We determine the wave functions for arbitrarily polarized quantum Hall states by employing the doublet model which has been proposed recently to describe arbitrarily polarized quantum Hall states. Our findings recover the well known fully polarized Laughlin wave functions and unpolarized Halperin wave function for the filling fraction $ν=2/5$. We have also c

  15. A. Klemm, W. Lerche, P. Mayr

    We analyze the map between heterotic and type II N=2 supersymmetric string theories for certain two and three moduli examples found by Kachru and Vafa. The appearance of elliptic j-functions can be traced back to specializations of the Picard-Fuchs equations to systems for $K_3$ surfaces. For the three-moduli example we write the mirror maps and Yukawa coupl

  16. Vittorio Del Duca

    In this talk we review the models describing the hard diffractive production of jets or more generally high-mass states in presence of rapidity gaps in hadron-hadron and lepton-hadron collisions. By rapidity gaps we mean regions on the lego plot in (pseudo)-rapidity and azimuthal angle where no hadrons are produced, between the jet(s) and an elastically scat

  17. K. S. Babu, R. N. Mohapatra

    We show that in minimal supersymmetric standard model (MSSM) with R-parity breaking as well as in the left-right symmetric model, there are new observable contributions to neutrinoless double beta decay arising from hitherto overlooked diagrams involving the exchange of one W boson and one scalar boson. In particular, in the case of MSSM, the present experim

  18. O. Entin-Wohlman, A. B. Harris, Amnon Aharony

    This paper derives the anisotropic superexchange interactions from a Hubbard model for excitations within the copper 3d band and the oxygen 2p band of the undoped insulating cuprates. We extend the recent calculation of Yildirim et al. [Phys. Rev. B {\bf VV}, pp, 1995] in order to include the most general on--site Coulomb interactions (including those which

  19. N. Kawashima

    We present cluster Monte Carlo algorithms for the $XYZ$ quantum spin models. In the special case of $S=1/2$, the new algorithm can be viewed as a cluster algorithm for the 8-vertex model. As an example, we study the $S=1/2$ $XY$ model in two dimensions with a representation in which the quantization axis lies in the easy plane. We find that the numerical aut

  20. Janet Cahn

    By strictest interpretation, theories of both centering and intonational meaning fail to predict the existence of pitch accented pronominals. Yet they occur felicitously in spoken discourse. To explain this, I emphasize the dual functions served by pitch accents, as markers of both propositional (semantic/pragmatic) and attentional salience. This distinction

  21. Giovanni Gallavotti

    It is shown that the "chaoticity hypothesis", analogous to Ruelle's principle for turbulence and recently introduced in statistical mechanics, implies the Onsager reciprocity and the fluctuation dissipation theorem in various models for coexisting transport phenomena.

  22. A. V. Ilinskaia, K. N. Ilinski, J. M. F. Gunn

    We consider the generalization of Haldane's state-counting procedure to describe all possible types of exclusion statistics which are linear in the deformation parameter $g$. The statistics are parametrized by elements of the symmetric group of the particles in question. For several specific cases we determine the form of the distribution functions which

  23. Paolo Pasti, Dmitrij Sorokin, Mario Tonin

    We consider a space-time invariant duality symmetric action for a free Maxwell field and an $SL(2,{\bf R})\times SO(6,22)$ invariant effective action describing a low-energy bosonic sector of the heterotic string compactified on a six-dimensional torus. The manifest Lorentz and general coordinate invariant formulation of the models is achieved by coupling du

  24. Bohuslav Balcar, Thomas Jech, Jindřich Zapletal

    We investigate classes of Boolean algebras related to the notion of forcing that adds Cohen reals. A >>Cohen algebra<< is a Boolean algebra that is dense in the completion of a free Boolean algebra. We introduce and study generalizations of Cohen algebras: semi-Cohen algebras, pseudo-Cohen algebras and potentially Cohen algebras. These classes of Boolean alg

  25. Vadim Kaplunovsky, Jan Louis, Stefan Theisen

    We collect further evidence for the proposed duality between $N=2$ heterotic and type II string vacua in a specific model suggested by Kachru and Vafa. In the gauge sector the previous analysis is extended; it is further shown that the duality also holds for the one--loop gravitational couplings to the vector multiplets.

  26. Yu-kui Zhou, Paul A. Pearce, Uwe Grimm

    The fusion procedure is implemented for the dilute $A_L$ lattice models and a fusion hierarchy of functional equations with an $su(3)$ structure is derived for the fused transfer matrices. We also present the Bethe ansatz equations for the dilute $A_L$ lattice models and discuss their connection with the fusion hierarchy. The solution of the fusion hierarchy

  27. Yu-kui Zhou

    The fusion procedure of dilute $A_L$ models is constructed. It has been shown that the fusion rules have two types: $su(2)$ and $su(3)$. This paper is concerned with the $su(2)$ fusion rule mainly and the corresponding functional relations of commuting transfer matrices in the $su(2)$ fusion hierarchy are found. Specially, it has been found that the fusion h

  28. K. Nakamura, Y. Oshiro, A. Tomimatsu

    Quantum-mechanical model of self-gravitating dust shell is considered. To clarify the relation between classical and quantum spacetime which the shell collapse form, we consider various time slicing on which quantum mechanics is developed. By considering the static time slicing which corresponds to an observer at a constant circumference radius, we obtain th

  29. J. Santos, M. J. Reboucas, A. F. F. Teixeira

    An algebraic classification of second order symmetric tensors in 5-dimensional Kaluza-Klein-type Lorentzian spaces is presented by using Jordan matrices. We show that the possible Segre types are $[1,1111]$, [2111], [311], [z,\bar{z},111], and the degeneracies thereof. A set of canonical forms for each Segre type is found. The possible continuous groups of s

  30. Dimitrios Psaltis, Frederick K. Lamb, Guy S. Miller

    A simple, physically consistent model has been proposed that seeks to explain in a unified way the X-ray spectra and rapid X-ray variability of the so-called Z sources and other accreting neutron stars in low-mass systems. Here we summarize the results of detailed numerical calculations of the X-ray spectra of the Z sources predicted by this model. Our compu

  31. Ian Smail, David W. Hogg, Lin Yan, Judy Cohen

    We present faint galaxy counts from deep $VRI$ images obtained with the Keck Telescope. These images reach $R\sim27$ in median seeing FWHM $\sim 0.5$--0.6 arcsec and we detect a integrated galaxy number density of $7\times 10^{5}$ degree$^{-2}$, equivalent to $3\times 10^{10}$ galaxies in the observable Universe. In addition we present median galaxy colors a

  32. Wei Lu

    By examining the symmetry constraints on the semi-inclusive pseudoscalar particle production in unpolarized inelastic lepton-hadron scattering, we present a complete, exact Lorentz decomposition for the corresponding hadronic tensor. As a result, we find that it contains five independent terms, instead of the four as have been suggested before. The newly ide

  33. Craig J. Copi, David N. Schramm, Michael S. Turner

    Deuterium is the best indicator of the baryon density; however, only its present abundance is known (and only locally) and its chemical evolution is intertwined with that of $^3$He. Because galactic abundances are spatially heterogeneous, mean chemical-evolution models are not well suited for extrapolating the pre-solar D and $^3$He abundances to their prime

  34. ZEUS Collaboration

    Inclusive jet cross sections for events with a large rapidity gap with respect to the proton direction from the reaction $ep \rightarrow jet \; + \; X$ with quasi-real photons have been measured with the ZEUS detector. The cross sections refer to jets with transverse energies $E_T^{jet}>8$~GeV. The data show the characteristics of a diffractive process media

  35. Werner Ruhl, Alexander Turbiner

    Translationally invariant symmetric polynomials as coordinates for $N$-body problems with identical particles are proposed. It is shown that in those coordinates the Calogero and Sutherland $N$-body Hamiltonians, after appropriate gauge transformations, can be presented as a {\it quadratic} polynomial in the generators of the algebra $sl_N$ in finite-dimensi

  36. Thomas G. Rizzo

    Single production of top quarks at hadron colliders via $gW$ fusion is examined as a probe of possible anomalous chromomagnetic and/or chromoelectric moment type couplings between the top and gluons. We find that this channel is far less sensitive to the existence of anomalous couplings of this kind than is the usual production of top pairs by $gg$ or $q\bar

  37. Kirill V. Krasnov

    Quantization of the system comprising gravitational, fermionic and electromagnetic fields is developed in the loop representation. As a result we obtain a natural unified quantum theory. Gravitational field is treated in the framework of Ashtekar formalism; fermions are described by two Grassmann-valued fields. We define a $C^{*}$-algebra of configurational

  38. K. Behrndt

    This model also known as chiral null model is a generalization of the gravitational wave and fundamental string background and is exact in the $\a&#39;$ expansion. The reduction to 4 dimensions yields a stationary IWP solution which couples to 7 gauge fields (one gravi-photon and 6 matter gauge fields) and 4 scalars. Special cases are the Taub-NUT geometry a

  39. G. Papp, W. Nörenberg

    The initial production and dynamical expansion of hot spherical nuclei are examined as the first stage in the projectile-multifragmentation process. The initial temperatures, which are necessary for entering the adiabatic spinodal region, as well as the minimum temperatures and densities, which are reached in the expansion, significantly differ for hard and

  40. Taco Nieuwenhuis, J. A. Tjon

    The Feynman-Schwinger representation is used to study the behavior of solutions of scalar QED in (2+1) dimensions. The limit of zero photon mass is seen to be smooth. The Bethe-Salpeter equation in the ladder approximation also exhibits this property. They clearly deviate from the behavior in the nonrelativistic limit. In a variational analysis we show that

  41. Andrew R Liddle, David H Lyth, David Roberts, Pedro P T Viana

    Motivated by recent developments in inflationary cosmology indicating the possibility of obtaining genuinely open universes in some models, we compare the predictions of cold dark matter (CDM) models in open universes with a variety of observational information. The spectrum of the primordial curvature perturbation is taken to be scale invariant (spectral in

  42. Hiroshi Shirokura

    We solve general 1-matrix models without taking the double scaling limit. A method of computing generating functions is presented. We calculate the generating functions for a simple and double torus. Our method is also applicable to more higher genus. Each generating function can be expressed by a ``specific heat&#39;&#39; function for sphere. Universal term

  43. Warren B. Perkins

    We construct field configurations that interpolate between string background states of differing baryon number. Using these configurations we estimate the effect of the background fields on the energy barrier separating different vacua. In the background of a superconducting GUT string the energy barrier is increased, while in an electroweak string backgroun

  44. Yu. S. Barash, A. V. Galaktionov, A. A. Svidzinsky

    Boundary conditions for unconventional superconducting order parameter are obtained on the basis of a microscopic theory. The upper critical field in a superconducting film is examined for unconventional superconductors with two-component order parameter and is compared with the case of accidental degeneracy. It is shown, that for both cases temperature depe

  45. Hyun-Chul Kim, Teruaki Watabe, Klaus Goeke

    The strange vector form factors are evaluated for $Q^2=0$ and $Q^2=1\ \mbox{GeV}^2$ in the framework of the SU(3) chiral quark-soliton model (or semi-bosonized SU(3) Nambu-Jona-Lasinio model). The rotational $1/N_c$ and $m_s$ corrections are taken into account up to linear order. The mean-square strange radius $\langle r^{2}\rangle^{Sachs}_{s}=-0.35\; \mbox{

  46. M. Jimbo, R. Kedem, H. Konno, T. Miwa

    The level-$1$ integrable highest weight modules of $U_q(\widehat{sl}_2)$ admit a level-$0$ action of the same algebra. This action is defined using the affine Hecke algebra and the basis of the level-$1$ module generated by components of vertex operators. Each level-$1$ module is a direct sum of finite-dimensional irreducible level-$0$ modules, whose highest

  47. Ralph Blumenhagen, Andreas Wisskirchen

    We present a construction of modular invariant partition functions for heterotic (0,2) supersymmetric classical string vacua. This generalization of Gepner&#39;s construction yields GUT gauge groups E_6, SO(10), SU(5) and SU(3) x SU(2) x U(1)^r, respectively. By calculating the massless spectrum of some of these models we find strong indications that they co

  48. Scott Thomas

    Supersymmetric flat directions can have a number of important consequences in the very early universe. Depending on the form of the SUSY breaking potential arising from the finite energy density at early times, coherent production of scalar condensates can result along such directions. This leads a cosmological disaster for Polonyi type flat directions with

  49. Ryusuke Ikeda

    It is shown that, within a Ginzburg-Landau (GL) formalism, the superconducting fluctuation is insulating at zero temperature even if the fluctuation dynamics is metallic (dissipative). Based on this fact, the low temperature behavior of the $H_{c2}$-line and the resistivity curves near a zero temperature transition are discussed. In particular, it is pointed

  50. C J Isham

    An introduction is given to an algebraic formulation and generalisation of the consistent histories approach to quantum theory. The main technical tool in this theory is an orthoalgebra of history propositions that serves as a generalised temporal analogue of the lattice of propositions of standard quantum logic. Particular emphasis is placed on those cases

  51. C. Dewdney, Z Malik

    The effect of introducing measuring devices in a ``quantum pinball&#39;&#39; system is shown to lead to a chaotic evolution for the particle position as defined in Bohm&#39;s approach to Quantum Mechanics.

  52. E. Caurier, J. L. Egido, G. Martinez-Pinedo, A. Poves

    The collective yrast band of the nucleus $^{48}$Cr is studied using the spherical shell model and the HFB method. Both approaches produce basically the same axially symmetric intrinsic state up to the - accurately reproduced - observed backbending. Agreement between both calculations extends to most observables. The only significant discrepancy comes from th

  53. D. M. Deaven, K. M. Ho

    We present a method for reliably determining the lowest energy structure of an atomic cluster in an arbitrary model potential. The method is based on a genetic algorithm, which operates on a population of candidate structures to produce new candidates with lower energies. Our method dramatically outperforms simulated annealing, which we demonstrate by applyi

  54. Alex Lesin

    We study monodromy action on abelian varieties satisfying certain bad reduction conditions. These conditions allow us to get some control over the Galois image. As a consequence we verify the Mumford--Tate conjecture for such abelian varieties.

  55. L. Clavelli

    We discuss the case for a light gluino and the mutual impact of this possibility with the Fermilab top quark candidates

  56. Lincoln Wolfenstein

    A recent experiment LSND at Los Alamos has provided\cite{1} an indication of $\overlineν_μ - \overlineν_e$ oscillations with $Δm^2$ of order 1ev$^2$ or greater and $\sin^2 2 θ_{e μ}$ between $2 \times 10^{-3}$ and $10^{2}$. Such a value of $Δm^2$ for $ν_μ - ν_e$ oscillations was not expected in the standard see-saw model\cite{2} suggested by SO(10) with a la

  57. G. L. Fogli, E. Lisi, G. Scioscia

    We present a new approach to the analysis of neutrino oscillation experiments, in the one mass-scale limit of the three-generation scheme. In this framework we reanalyze and recombine the most constraining accelerator and reactor data, in order to draw precise bounds in the new parameter space. We consider our graphical representations as particularly suited

  58. M. B. Gay Ducati, Alvaro L. Ayala, E. Levin

    In this talk we present the first calculation of the gluon structure function for nucleus in QCD. We discuss the Glauber formula for the gluon structure function and the violation of this simple approach that we anticipate in QCD. (Talk given by E. Levin at QCD and nuclear target session at the Workshop on Deep Inelastic Scattering and QCD, Paris, April 1995

  59. Stefano Catani

    I present some comments on the relationship between the small-$x$ behaviour of the parton (quark and gluon) densities and the scaling violation of the proton structure function $F_{2}(x,Q^{2})$.

  60. S. V. Goloskokov

    It is shown that the longitudinal double spin asymmetry $A_{ll}$ in polarized diffractive $l p \to l p+Q \bar Q$ reaction depends strongly on the spin structure of quark-pomeron vertex. The SMC spin facilities may be one of the best place to perform such experiment.

  61. Atsushi Hosaka, Niels R. Walet

    We investigate the isoscalar and isovector components of the axial vector coupling constants, $g_A^{(0)}$ and $g_A$, using algebraic models that lead to the correct symmetries of large-$N_c$ QCD. Results obtained previously in various chiral models are interpreted from this algebraic point of view. The results of the Skyrme model and the valence quark model

  62. Marc Chemtob, Kurt Langfeld

    Scalar QED with fermions is investigated in an expansion in powers of the inverse gauge coupling constant. The fermion mass generation is studied in next to leading order of the strong coupling expansion for the Higgs-phase of the model. Chiral symmetry breaking is discussed. Our approach supports from a strong coupling point of view the results obtained ear

  63. Hai-Yang Cheng

    Status of nonfactorizable effects in exclusive hadronic weak decays of $D$ and $B$ mesons is reviewed.

  64. NuTeV Collaboration

    The Gross Llewellyn Smith sum rule has been measured at different values of four-momentum transfer squared ($Q^{2}$) by combining the precise CCFR neutrino data with data from other deep-inelastic scattering experiments at lower values of $Q^{2}$. A comparison with the ${\cal O}(α^{3}_{s})$ predictions of perturbative QCD yields a determination of $α_{s}$ an

  65. Junichi Iwasaki

    Tangles of loops which approximate an aspect of the Kerr-Newman black hole metrics at large scales compared to the Planck length are constructed. The physical aspect the tangles approximate is discussed. This construction may be useful in the loop representation of canonical quantum gravity. Implications and applications of the tangles are remarked.

  66. A. Crisanti, M. Falcioni, A. Vulpiani

    A network of $N$ elements is studied in terms of a deterministic globally coupled map which can be chaotic. There exists a range of values for the parameters of the map where the number of different macroscopic configurations is very large, and there is violation of selfaveraging. The time averages of functions, which depend on a single element, computed ove

  67. L. Schweitzer, I. Kh. Zharekeshev

    The energy level statistics of 2D electrons with spin-orbit scattering are considered near the disorder induced metal-insulator transition. Using the Ando model, the nearest-level-spacing distribution is calculated numerically at the critical point. It is shown that the critical spacing distribution is size independent and has a Poisson-like decay at large s

  68. R. J. Smith, B. J. Boyle, S. J. Maddox

    We have carried out an investigation of the galaxy environments of low redshift ($z<0.3$) QSOs by cross-correlating the positions on the sky of X-ray-selected QSOs/AGN identified in the {\it Einstein} Medium Sensitivity Survey (EMSS) with those of $B_J<20.5$ galaxies in the APM galaxy catalogues. At $<5\,$arcmin, we find a significant ($5σ$) galaxy excess ar

  69. R. DiStefano, A. A. Esin

    When there is more than one source of light along the line of sight to a gravitationally lensed object, the characteristics of the observed light curve are influenced by the presence of the light that is not lensed. In this paper we develop a formalism to quantify the associated effects. We find it useful to introduce the concept of a ``blended Einstein radi

  70. M. Markevitch, R. Mushotzky, H. Inoue, K. Yamashita

    Using ASCA data, we have measured the electron temperature in A2163 out to 1.5h^{-1} Mpc (10a_x) from the center, in three radial bins. The temperatures are 12.2+1.9-1.2 keV, 11.5+2.7-2.9 keV and 3.8+1.1-0.9 keV (90%) in the 0-3 a_x (0-3.5&#39;), 3-6 a_x and 6-13 a_x spherical shells, respectively. Applying the hydrostatic equilibrium and spherical symmetry

  71. Robert M. Harris

    We present three searches for new particles at CDF. First, using 70 pb^-1 of data we search the dijet mass spectrum for resonances. There is an upward fluctuation near 550 GeV (2.6 sigma) with an angular distribution that is adequately described by either QCD alone or QCD plus 5% signal. There is insufficient evidence to claim a signal, but we set the most s

  72. Michael Martin Nieto, D. Rodney Truax

    As an aid to understanding the {\it displacement operator} definition of squeezed states for arbitrary systems, we investigate the properties of systems where there is a Holstein-Primakoff or Bogoliubov transformation. In these cases the {\it ladder-operator or minimum-uncertainty} definitions of squeezed states are equivalent to an extent displacement-opera

  73. Eugene Lerman, Yael Karshon

    Let Phi : M --> g^* be a proper moment map associated to an action of a compact connected Lie group, G, on a connected symplectic manifold, (M,ω). A collective function is a pullback via Φof a smooth function on g^*. In this paper we present four new results about the relationship between the collective functions and the G-invariant functions in the Poisson

  74. K. S. McFarland, D. Naples

    We present limits on $ν_μ(\barν_μ)\toν_τ(\barν_τ)$ and $ν_μ(\barν_μ)\toν_e(\barν_e)$ oscillations based on a study of inclusive $νN$ interactions performed using the CCFR massive coarse grained detector in the FNAL Tevatron Quadrupole Triplet neutrino beam. The sensitivity to oscillations is from the difference in the longitudinal energy deposition pattern o

  75. J. Schaffner, I. N. Mishustin

    We study the equation of state of hyperon-rich matter for neutron stars using an extended relativistic mean-field model. We take special care of the recently proposed non-linear behaviour of the vector field which gives a much better description of Dirac-Brueckner calculations. The hyperon-hyperon interaction is also implemented by introducing additional mes

  76. P. Colangelo, F. De Fazio, G. Nardulli

    We propose a method to determine the leptonic decay constant $f_{B^*}$ in the infinite heavy quark mass limit from the analysis of the radiative decay mode $B^- \to \ell^- {\bar ν}_\ell γ$. The method relies on HQET symmetries and on experimental data from $D^{*0} \to D^0 γ$.

  77. M. G. Ryskin, Yu. M. Shabelski, A. G. Shuvaev

    The cross sections of heavy quark production in $pp$ collision and for their photo- and electroproduction are calculated in the framework of QCD. The virtual nature of the interacting gluons as well as their transverse motion and different polarizations are taken into account. The obtained cross sections exhibit more rapid growth with the initial energy than

  78. M. Pitkänen

    The mathematical basis of p-adic Higgs mechanism discussed in papers hep-th@xxx.lanl.gov 9410058-62 is considered in this paper. The basic properties of p-adic numbers, of their algebraic extensions and the so called canonical identification between positive real numbers and p-adic numbers are described. Canonical identification induces p-adic topology and d

  79. Xiao-Gang Wen

    Fractional quantum Hall (FQH) liquids contain extremely rich internal structures which represent a whole new kind of ordering. We discuss characterization and classification of the new orders (which is called topological orders). We also discuss the edge excitations in FQH liquids, which form the so-called chiral Luttinger liquids. The chiral Luttinger liqui

  80. Pilar Hernandez, Raman Sundrum

    We formulate chiral gauge theories non-perturbatively, using two different cuttoffs for the fermions and gauge bosons. We use a lattice with spacing $b$ to regulate the gauge fields in standard fashion, while computing the chiral fermion determinant on a finer lattice with spacing $f << b$. This determinant is computed in the background of $f$-lattice gauge

  81. Z. Malik, C. Dewdney

    The quantum counterpart of the classically chaotic kicked rotor is investigated using Bohm&#39;s appraoch to quantum theory.

  82. Claudia Eberlein

    Sonoluminescence is explained in terms of quantum radiation by moving interfaces between media of different polarizability. In a stationary dielectric the zero-point fluctuations of the electromagnetic field excite virtual two-photon states which become real under perturbation due to motion of the dielectric. The sonoluminescent bubble is modelled as an opti

  83. Claudia Eberlein

    Sonoluminescence is explained in terms of quantum radiation by moving interfaces between media of different polarizability. It can be considered as a dynamic Casimir effect, in the sense that it is a consequence of the imbalance of the zero-point fluctuations of the electromagnetic field during the non-inertial motion of a boundary. The transition amplitude

  84. G. Gallatin

    Fused Silica is the material of choice for UV optical systems such as the projection optics in microlithography systems. Unfortunately fused silica is not stable under UV irradition and undergoes compaction and color center formation. The UV damage properties of fused silica have been the subject of a number of studies. The detailed microscopic mechanism for

  85. Andrzej Rosłanowski, Saharon Shelah

    In the present paper we are interested in properties of forcing notions which measure in a sense the distance between the ground model reals and the reals in the extension. We look at the ways the ``new&#39;&#39; reals can be aproximated by ``old&#39;&#39; reals. We consider localizations for infinite subsets of omega. Though each member of [omega]^omega can

  86. Erik Koelink

    A general addition formula for a two-parameter family of Askey-Wilson polynomials is derived from the quantum $SU(2)$ group theoretic interpretation. This formula contains most of the previously known addition formulas for $q$-Legendre polynomials as special or limiting cases. A survey of the literature on addition formulas for $q$-special functions using qu

  87. Marco Matone

    We find the transformation properties of the prepotential ${\cal F}$ of $N=2$ SUSY gauge theory with gauge group $SU(2)$. In particular we show that ${\cal G}(a)=πi\left({\cal F}(a)-{1\over 2}a\partial_a{\cal F}(a)\right)$ is modular invariant. This function satisfies the non-linear differential equation $\left(1-{\cal G}^2\right){\cal G}&#39;&#39;+{1\over 4

  88. Edward Witten

    The vanishing of the cosmological constant and absence of a massless dilaton might be explained by a duality between a supersymmetric string vacuum in three dimensions and a non-supersymmetric string vacuum in four dimensions.

  89. Igor Pesando

    We investigate the generalized Gross-Neveu model using the discretized light cone quantization and we find that the vacuum of the bare theory is {\sl non} trivial in presence of vectorial current coupling when the simplest and most natural form of quantum constraints is used. Nevertheless the vacuum of the renormalized theory is trivial. In the thermodynamic

  90. J. Gladikowski, B. M. A. G. Piette, B. J. Schroers

    A gauged (2+1)-dimensional version of the Skyrme model is investigated. The gauge group is $U(1)$ and the dynamics of the associated gauge potential is governed by a Maxwell term. In this model there are topologically stable soliton solutions carrying magnetic flux which is not topologically quantized. The properties of rotationally symmetric solitons of deg

  91. Markus A. Luty, Washington Taylor

    We give a simple description of the classical moduli space of vacua for supersymmetric gauge theories with or without a superpotential. The key ingredient in our analysis is the observation that the lagrangian is invariant under the action of the complexified gauge group $\Gc$. From this point of view the usual $D$-flatness conditions are an artifact of Wess

  92. Patricia Ball

    We determine $|V_{cb}|$ from inclusive semileptonic B decays including resummation of supposedly large perturbative corrections, which originate from the running of the strong coupling. We argue that the low value of the BLM scale found previously for inclusive decays is a manifestation of the renormalon divergence of the perturbative series starting already

  93. Tomislav Prokopec

    In this lecture first I present a brief genesis of the ideas on the electroweak baryogenesis and then I focus on a mechanism in which the source of $CP$ violation is a $CP$-violating field condensate which could occur, for example, in multi-higgs extensions of the Standard Model. In the limit of a thick bubble wall one finds a classical force acting on parti

  94. E. Kh. Akhmedov

    Left--right symmetry breaking in a model with composite Higgs scalars is discussed. It is assumed that the low--energy degrees of freedom are just fermions and gauge bosons and that the Higgs bosons are generated dynamically through a set of gauge-- and parity--invariant 4-fermion operators. It is shown that in a model with composite bi-doublet and two tripl

  95. V. Ilyin, A. Pukhov, V. Savrin, A. Semenov

    We study a possibility to measure the anomalous magnetic moment of vector leptoquarks in reactions with single leptoquark production associated with hard photon emission in ep collisions. For this purpose we propose to use the radiative amplitude zero effect. We find that an exact radiative zero in the angular distribution of the emitted photon is present on

  96. D. Graudenz, M. Hampel, A. Vogt, Ch. Berger

    A new method is presented to determine the gluon density in the proton from jet production in deeply inelastic scattering. By using the technique of Mellin transforms not only for the solution of the scale evolution equation of the parton densities but also for the evaluation of scattering cross sections, the gluon density can be extracted in next-to-leading

  97. A. Nakamura, H. Aiso, M. Fukuda, T. Iwamiya

    We present SU(3) gluon propagators calculated on 48*48*48*N_t lattices at beta=6.8 where N_t=64 (corresponding the confinement phase) and N_t=16 (deconfinement) with the bare gauge parameter,alpha, set to be 0.1. In order to avoid Gribov copies, we employ the stochastic gauge fixing algorithm. Gluon propagators show quite different behavior from those of mas

  98. E. -M. Ilgenfritz, J. Kripfganz, H. Perlt, A. Schiller

    We study the electroweak phase transition by lattice simulations of an effective 3-dimensional theory, for a Higgs mass of about $35 GeV$. In the broken symmetry phase our results on masses and the Higgs condensate are consistent with 2-loop perturbative results. However, we find a non-perturbative lowering of the transition temperature, similar to the one p

  99. James E. Lidsey

    The quantum cosmology of two-dimensional dilaton-gravity models is investigated. A class of models is mapped onto the constrained oscillator-ghost-oscillator model. A number of exact and approximate solutions to the corresponding Wheeler-DeWitt equation are presented. A wider class of minisuperspace models that can be solved in this fashion is identified. Su

  100. O. Brodbeck, M. Heusler, N. Straumann

    The pulsation equations for spherically symmetric black hole and soliton solutions are brought into a standard form. The formulae apply to a large class of field theoretical matter models and can easily be worked out for specific examples. The close relation to the energy principle in terms of the second variation of the Schwarzschild mass is also establishe