Research archive

arXiv papers from May 1994

The most recent 100 records published that month. Open any paper for its original abstract, citation metadata, related research, and reading tools.

  1. P. Binetruy, E. Dudas

    We show that a recent proposal by Nambu to generate a hierarchy among Yukawa couplings in the standard model may be easily implemented in superstring models. In such models, two of the main ingredients of the Nambu proposal find a natural explanation: minimising with respect to the Yukawas amounts to a minimisation with respect to the underlying moduli field

  2. Ye-Yi Wang

    We introduce the bilingual dual-coding theory as a model for bilingual mental representation. Based on this model, lexical selection neural networks are implemented for a connectionist transfer project in machine translation. This lexical selection approach has two advantages. First, it is learnable. Little human effort on knowledge engineering is required.

  3. Neta A. Bahcall, Renyue Cen, Mirt Gramann

    What is the role of clusters of galaxies in probing the large-scale velocity field of the universe? We investigate the distribution of peculiar velocities of clusters of galaxies in the popular low-density ($\Omega=0.3$) flat Cold-Dark-Matter (CDM) cosmological model, which best fits many large-scale structure observations. An $\Omega=1$ CDM model is also st

  4. Tereasa G. Brainerd, Ian Smail, Jeremy R. Mould

    We present results for the two-point angular correlation function of galaxies to a limiting magnitude of r=26. The final sample is 97% complete to r=26.0, yielding 5730 galaxies over a 90.1 sq. arcmin field. The correlation function for our faint galaxies can be parameterised by a power law, $A \theta^{-0.8}$, in agreement with the clustering statistics of s

  5. Tomoki Nakanishi

    Based on the formulation of Drinfel'd, Chari, and Pressley, a technique to analyze the structure of tensor products of the Yangian algebra representations is presented. We then apply the results to the $S$-matrix theory of the $G\otimes G$-invariant nonlinear $\sigma$-model ($G$-principal chiral model) by Ogievetsky, Reshetikhin, and Wiegmann. We show how th

  6. Brian Chaboyer

    Light element ($^6$Li, $^7$Li and $^9$Be) depletion isochrones for halo stars have been calculated with standard stellar evolution models. These models include the latest available opacities and are computed through the sub-giant branch. If $^6$Li is not produced in appreciable amounts by stellar flares, then the detection of $^6$Li in HD 84937 by Smith, Lam

  7. Gilbert N. Lewis

    In this paper, the behavior of a spherical hole in an otherwise infinite and uniform universe is investigated. First, the Newtonian theory is developed. The concept of negative gravity, an outward gravitational force acting away from the center of the spherical hole, is presented, and the resulting expansion of the hole is investigated. Then, the same result

  8. C. Teitelboim

    We review the insights into black hole entropy that arise from the formulation of gravitation theory in terms of dimensional continuation. The role of the horizon area and the deficit angle of a conical singularity at the horizon as canonically conjugate dynamical variables is analyzed. The path integral and the extension of the Wheeler-De Witt equation for

  9. I. S. Towner

    Calculations of the axial-vector component to the radiative correction for superallowed Fermi $0^+ \rightarrow 0^+$ nuclear beta decay are here modified with quenched rather than free-nucleon coupling constants for the axial-vector and electromagnetic interactions with nucleons. The result increases the deduced value of $V_{ud}$ but does not restore unitarit

  10. E. Kolbe, K. Langanke, P. Vogel

    We use the continuum random phase approximation to describe the muon capture on C-12, O-16 and Ca-40. We reproduce the experimental total capture rates on these nuclei to better than 10% using the free nucleon weak form factors and two different residual interactions. However, the calculated rates for the same residual interactions are significantly lower th

  11. Joseph Silk

    If the COBE detection of CMB fluctuations is used to normalize the power spectrum of primordial density fluctuations in a cold dark matter--dominated universe, early reionization is likely to result in a substantial diminution of primordial temperature fluctuations on degree scales. I argue that the reionization may be non--Gaussian because of feedback effec

  12. S. Catterall

    Recent models for discrete euclidean quantum gravity incorporate a sum over simplicial triangulations. We describe an algorithm for simulating such models in general dimensions. As illustration we show results from simulations in four dimensions

  13. R. Barbieri, Z. Berezhiani, G. Dvali, L. Hall

    We consider the flavour problem in a supersymmetric Grand Unified theory with gauged SU(6) group, where the Higgs doublets are understood as pseudo-Goldstone bosons of a larger $\SU(6)\otimes\SU(6)$ global symmetry of the Higgs superpotential. A key element of this work is that we never appeal to any flavour symmetry. One main interesting feature emerges: on

  14. P. Wilhelm, J. A. Niskanen, H. Arenhövel

    The cross section of the reaction $^3$He$(\gamma,pn)p_{spec}$ in the energy range 150 - 450 MeV has been calculated in a quasifree two-body model and compared with a recent kinematically complete experiment. In comparison with free deuteron disintegration the cross section is increased by a factor of about 1.5 in reasonable agreement with the data for photon

  15. Mikhail Bilenky, Arcadi Santamaria

    The contributions of non-standard four-neutrino contact interactions to electroweak observables are considered at the one-loop level by using the effective quantum field theory. The analysis is done in terms of three unknown parameters: the strength of the non-standard neutrino interactions, $\tilde{F}$, an additional derivative coupling needed to renormaliz

  16. Gérard Clément, Ilhem Zouzou

    We determine the different possible space-time metrics inside an infinite rotating hollow cylinder with given energy density and longitudinal and azimuthal stresses, the metric outside the cylinder being chosen of the spinning cosmic string type. The solutions we obtain for various domains of values of the cylinder parameters include a space-time with topolo

  17. X. Artru, J. Czyzewski, H. Yabuki

    We calculate the single spin asymmetry in the inclusive pion production in proton-proton collisions. We generate the asymmetry at the level of fragmentation function (Collins effect) by the Lund coloured string mechanism. We compare our results with the Fermilab E704 data from polarized proton-proton collisions at 200 GeV. We show that the transversely polar

  18. A. Love, W. A. Sabra, S. Thomas

    Target space symmetries are studied for orbifold compactified string theories containing Wilson line background fields. The symmetries determined are for those moduli which contribute to the string loop threshold corrections of the gauge coupling constants. The groups found are subgroups of the modular group $PSL(2, Z)$ and depend on the choice of discrete W

  19. G. Burdman, T. Goldman, D. Wyler

    We compute the photon spectrum and the rate for the decays $B(D)\to l\nu_l\gamma$ These photonic modes constitute a potentially large background for the purely leptonic decays which are used to extract the heavy meson decay constants. While the rate for $D\to l\n\g$ is small, the radiative decay in the $B$ meson case could be of comparable magnitude or even

  20. R. Tateo

    The ground state of the $\SO(2n)_{1} \times \SO(2n)_{1} \over \SO(2n)_{2}$ coset theories, perturbed by the $\phi^{id,id}_{adj}$ operator and those of the sine-Gordon theory, for special values of the coupling constant in the attracting regime, is the same. In the first part of this paper we extend these results to the $\SO(2n-1)$ cases. In the second part,

  21. D. P. Chu, P. N. Butcher

    With a model calculation, we demonstrate that a non-invasive measurement of intrinsic quantum Hall effect defined by the local chemical potential in a ballistic quantum wire can be achieved with the aid of a pair of voltage leads which are separated by potential barriers from the wire. B\"uttiker's formula is used to determine the chemical potential being me

  22. J. Ellis, N. Mavromatos, D. Nanopoulos

    We discuss some physical aspects of our Liouville approach to non-critical strings, including the emergence of a microscopic arrow of time, effective field theories as classical ``pointer'' states in theory space, $CPT$ violation and the possible apparent non-conservation of angular momentum. We also review the application of a phenomenological parametrizati

  23. A. Jakovác, A. Patkós

    Direct evaluation of the 1-loop fluctuation determinant of non-static degrees of freedom in a complete static background is advocated to be more efficient for the determination of the effective three-dimensional model of the electroweak phase transition than the one-by-one evaluation of Feynman diagrams. The relation of the couplings and fields of the effect

  24. Bo Sundborg

    The tensionless limit of classical string theory may be formulated as a topological theory on the world-sheet. A vector density carries geometrical information in place of an internal metric. It is found that path-integral quantization allows for the definition of several, possibly inequivalent quantum theories. String amplitudes are constructed from vector

  25. J. L. Cortes, M. S. Plyushchay

    The vector system of linear differential equations for a field with arbitrary fractional spin is proposed using infinite-dimensional half-bounded unitary representations of the $\overline{SL(2,R)}$ group. In the case of $(2j+1)$-dimensional nonunitary representations of that group, $0<2j\in Z$, they are transformed into equations for spin-$j$ fields. A local

  26. V. Marotta, A. Sciarrino

    The main properties of indefinite Kac-Moody and Borcherds algebras, considered in a unified way as Lorentzian algebras, are reviewed. The connection with the conformal field theory of the vertex operator construction is discussed. By the folding procedure a class of subalgebras is obtained.

  27. L. Del Debbio A. Di Giacomo G. Paffuti P. Pieri

    A monopole creation operator is constructed: its vacuum expectation value is an order parameter for dual superconductivity in that, if different from zero it signals spontaneous breaking of the U(1) symmetry corresponding to monopole charge conservation. The operator is tested on compact U(1) gauge theory on lattice. For SU(2) gauge theory it clearly demonst

  28. G. Barnich, F. Brandt, M. Henneaux

    Yang-Mills models with compact gauge group coupled to matter fields are considered. The general tools developed in a companion paper are applied to compute the local cohomology of the BRST differential $s$ modulo the exterior spacetime derivative $d$ for all values of the ghost number, in the space of polynomials in the fields, the ghosts, the antifields (=s

  29. John Carroll

    The paper demonstrates that exponential complexities with respect to grammar size and input length have little impact on the performance of three unification-based parsing algorithms, using a wide-coverage grammar. The results imply that the study and optimisation of unification-based parsing must rely on empirical data until complexity theory can more accur

  30. J. M. Deutsch, Hyoungsoo Yoon

    We consider the force on the end of a polymer chain being pulled through a network at velocity $v$, using computer simulations. We develop algorithms for measuring the force on the end of the chain using lattice models of polymers. Our algorithm attaches a spring to the end being pulled and uses its average extension to calculate the force. General problems

  31. A. de Rujula

    Electromagnetism would be a ``more unified'' theory if there were elementary magnetic monopoles and/or particles with both electric and magnetic charges (dyons). I discuss the simplest possibilities for the addition of these entities onto the Standard Model, and their empirical consequences. Lower limits on the masses of monopoles and dyons stemming from the

  32. Andrzej Czarnecki, Ulrich Kilian, Dirk Kreimer

    We present a new method of calculating scalar propagator and vertex functions in the two-loop approximation, for arbitrary masses of particles. It is based on a double integral representation, suitable for numerical evaluation. Real and imaginary parts of the diagrams are calculated separately, so that there is no need to use complex arithmetics in the numer

  33. K. Funakubo, A. Kakuto, S. Otsuki, K. Takenaga

    By treating CP-violating interaction as a perturbative term, we solve the Dirac equation in the background of electroweak bubble wall (the distorted wave Born approximation). We obtain the transmission and reflection coefficients for a chiral fermion incident from the symmetric-phase region and for the one from the broken-phase region respectively. There hol

  34. Frank Cuypers, Karol Kolodziej, Reinhold Rueckl

    We study polarized $e^-e^-$ scattering into $\WW$, $\WZ$ and $\ZZ$ final states within the framework of the standard model of electroweak interactions. These mechanisms for producing pairs of weak gauge bosons are potential backgrounds to new reactions beyond the realm of the standard model. At a centre-of-mass energy of 500 GeV the total cross sections are

  35. A. Ashtekar, Ranjeet S. Tate

    An extension of the Dirac procedure for the quantization of constrained systems is necessary to address certain issues that are left open in Dirac's original proposal. These issues play an important role especially in the context of non-linear, diffeomorphism invariant theories such as general relativity. Recently, an extension of the required type was propo

  36. I. M. Gioia, G. A. Luppino

    An atlas of deep, wide-field R-band CCD images of a complete sample of distant, X-ray-selected clusters of galaxies is presented. These clusters are the 41 most distant (z>= 0.15) and most X-ray luminous (Lx >= 2x10**44 erg\s-1) clusters in the Einstein Observatory Extended Medium Sensitivity Survey (EMSS) catalog that are observable from Mauna Kea (delta >

  37. H. Kawabe, T. Kobayashi, N. Ohtsubo

    We examine whether a minimal string model possessing the same massless spectra as the MSSM can be obtained from $Z_4$, $Z_6$ and $Z_8$ orbifold constructions. Using an anomaly cancellation condition of the target space duality symmetry, we derive allowable values of a level $k_1$ of U(1)$_Y$ for the minimal string model on the orbifolds through computer anal

  38. Dirk Kreimer

    We sketch a systematic approach to multiloop calculations. We focus on the Z-factors of a renormalizable theory and show that they can be obtained by purely algebraic methods based on power-counting and the forest structure of the divergent graphs. (submitted contributions to the conference proceedings "Confronting the Infinite", Adelaide February 1994)

  39. Tim Bedford, Albert M. Fisher

    Given a $C^{1+\gamma}$ hyperbolic Cantor set $C$, we study the sequence $C_{n,x}$ of Cantor subsets which nest down toward a point $x$ in $C$. We show that $C_{n,x}$ is asymptotically equal to an ergodic Cantor set valued process. The values of this process, called limit sets, are indexed by a H\"older continuous set-valued function defined on D. Sullivan's

  40. A. Loeb, F. A. Rasio, J. Shaham

    Recent observations by the ROSAT X-ray satellite of the Vela supernova remnant have revealed, in addition to the previously identified compact nebula, a nearly circular emitting region with a radius of about 4 degrees. The Vela pulsar is slightly off the center of this circular region, consistent with its measured proper motion of about 100km/s and an age of

  41. Pierluigi Monaco

    We show that observational data for four Abell clusters of galaxies support the Gur\-za\-dyan-Kocharyan relation between the Hausdorff dimension and the dynamical properties of a galaxy system. The Hausdorff dimension is calculated using the two-point correlation function, while the dynamical parameters are estimated using available data and reasonable assum

  42. Michael Gasser

    This paper describes a modular connectionist model of the acquisition of receptive inflectional morphology. The model takes inputs in the form of phones one at a time and outputs the associated roots and inflections. In its simplest version, the network consists of separate simple recurrent subnetworks for root and inflection identification; both networks ta

  43. Vladimir Zelevinsky, Mihai Horoi, B. Alex Brown

    The energies and wave functions of stationary many-body states are analyzed to look for the signatures of quantum chaos. Shell model calculations with the Wildenthal interaction are performed in the $J-T$ scheme for 12 particles in the $sd$-shell. The local level statistics are in perfect agreement with the GOE predictions. The analysis of the amplitudes of

  44. H. Kinzelbach, M. Lassig

    We develop a renormalized continuum field theory for a directed polymer interacting with a random medium and a single extended defect. The renormalization group is based on the operator algebra of the pinning potential; it has novel features due to the breakdown of hyperscaling in a random system. There is a second-order transition between a localized and a

  45. I. I. Bigi, M. Shifman, N. G. Uraltsev, A. Vainshtein

    We show how sum rules for the weak decays of heavy flavor hadrons can be derived as the moments of spectral distributions in the small velocity (SV) limit. This systematic approach allows us to determine corrections to these sum rules, to obtain new sum rules and it provides us with a transparent physical interpretation; it also opens a new perspective on th

  46. H. C. Rosu

    In the scattering picture, thermal radiation effects may be associated with the `above barrier' reflection coefficient, which comes into play because of complex turning points. This note contains several general remarks on the application of the above statement to Schwarzschild black hole radiance

  47. Wojciech Wiślicki

    Analysis was performed of semi-inclusive and inclusive spin asymmetries determined from the polarized deep inelastic scattering by the Spin Muon Collaboration. Combined analysis of data for polarized deuterium and hydrogen targets allows for separate determination of spin carried by valence {\it u} and {\it d} quarks and non-strange sea quarks as a function

  48. D. Kharzeev, H. Satz

    The cross section for the \J~and \U~interaction with light hadrons is calculated in short-distance QCD, based on the large heavy quark mass and the resulting large energy gap to open charm or beauty. The low energy form of the cross section is determined by the gluon structure functions at large $ x$; hence it remains very small until quite high energies. Th

  49. Eckhard Meinrenken

    A Theorem due to Guillemin and Sternberg about geometric quantization of Hamiltonian actions of compact Lie groups $G$ on compact Kaehler manifolds says that the dimension of the $G$-invariant subspace is equal to the Riemann-Roch number of the symplectically reduced space. Combined with the shifting-trick, this gives explicit formulas for the multiplicities

  50. W. de Boer, R. Ehret, D. I. Kazakov

    It is shown that a top mass of 174+/-17 GeV, as quoted recently by the CDF Collaboration, constrains the mixing angle between the Higgs doublets in the Minimal Supersymmmetric extension of the Standard Model (MSSM) to: 1.2<tan beta<5.5 at the 90% C.L.. The most probable value corresponds to tan beta = 1.56; such a small value causes a large mixing in the sto

  51. Tim R. Morris

    We investigate the Exact Renormalization Group (ERG) description of ($Z_2$ invariant) one-component scalar field theory, in the approximation in which all momentum dependence is discarded in the effective vertices. In this context we show how one can perform a systematic search for non-perturbative continuum limits without making any assumption about the for

  52. John McMahon, F. J. Smith

    This paper describes an automatic word classification system which uses a locally optimal annealing algorithm and average class mutual information. A new word-class representation, the structural tag is introduced and its advantages for use in statistical language modelling are presented. A summary of some results with the one million word LOB corpus is give

  53. Suresh Manandhar

    This paper provides a model theoretic semantics to feature terms augmented with set descriptions. We provide constraints to specify HPSG style set descriptions, fixed cardinality set descriptions, set-membership constraints, restricted universal role quantifications, set union, intersection, subset and disjointness. A sound, complete and terminating consiste

  54. Akira Fujii, Takeo Inami

    We study the $O(N)$ nonlinear $\sigma$ model on a three-dimensional compact space $S^1 \times S^2$ (of radii $L$ and $R$ respectively) by means of large $N$ expansion, focusing on the finite size effects and conformal symmetries of this model at the critical point. We evaluate the correlation length and the Casimir energy of this model and study their depend

  55. A. Ghinculov, J. J. van der Bij

    Formulae are provided to express any two-loop scalar integral with arbitrary masses and arbitrary external momenta in terms of an integral of one fairly simple function or of its derivatives. Such integrals can be calculated numerically with high precision. Good agreement is found with known analytical expressions of specific two--loop diagrams. To prove the

  56. Claire Grover, Chris Brew, Suresh Manandhar, Marc Moens

    We describe an implementation in Carpenter's typed feature formalism, ALE, of a discourse grammar of the kind proposed by Scha, Polanyi, et al. We examine their method for resolving parallelism-dependent anaphora and show that there is a coherent feature-structural rendition of this type of grammar which uses the operations of priority union and generalizati

  57. G. Cvetic

    We {works done in collaboration with C.S.Kim, Yonsei Univ., Seoul, Korea} present some properties of the SM with two Higgs doublets. Unlike the minimal SM, the Yukawa couplings (in the usual ``type II'' model) converge with the increasing energy to flavor democracy (FD), i.e.~to common values, in a specific flavor basis. This may represent a possible signal

  58. G. Cvetic, C. S. Kim

    In the Standard Model with two Higgs doublets (type II), which has a consistent trend to a flavor gauge theory and its related flavor democracy in the quark and the leptonic sectors (unlike the minimal Standard Model) when the energy of the probes increases, we impose the mixed quark-lepton flavor democracy at high ``transition'' energy and assume the usual

  59. A. Bottino, N. Fornengo, G. Mignola, S. Scopel

    We review some properties of the neutralino as a candidate for dark matter in the Universe. After presentation of evaluations for the neutralino relic abundance, possibilities for its direct and indirect detections are discussed, with emphasis for measurements at neutrino telescopes.

  60. Suresh Govindarajan

    We report work done with T. Jayaraman (hep-th/9405146) in this talk. In a recent paper, Hitchin introduced generalisations of the Teichmuller space of Riemann surfaces. We relate these spaces to the Teichmuller spaces of W-gravity. We show how this provides a covariant description of W-gravity and naturally leads to a Polyakov path integral prescription for

  61. S. Ferrara, C. Kounnas, F. Zwirner

    We study some conditions for the hierarchy $m_{3/2} << M_P$ to occur naturally in a generic effective supergravity theory. Absence of fine-tuning and perturbative calculability require that the effective potential has a sliding gravitino mass and vanishing cosmological constant, up to ${\cal O}(m_{3/2}^4)$ corrections. In particular, cancellation of quadrati

  62. Carsten Grosse-Knetter

    The equivalence theorem states that the leading part of the amplitude for a process with external longitudinally polarized vector bosons is given by the amplitude in which the longitudinal vector bosons are replaced by the corresponding pseudo-Goldstone bosons. The validity of this theorem within the standard model with a heavy Higgs boson and within the gau

  63. Sean A. Hayward

    A formula is given for the variation of the Hawking energy along any one-parameter foliation of compact spatial 2-surfaces. A surface for which one null expansion is positive and the other negative has a preferred orientation, with a spatial or null normal direction being called outgoing or ingoing as the area increases or decreases respectively. A natural w

  64. Harald Fritzsch

    It is shown that a simple breaking of the subnuclear democracy leads to a successful description of the mixing between the second and third family. In the lepton channel the $\nu _{\mu } - \nu_{\tau }$ oscillations are expected to be described by a mixing angle of $2.65^ {\circ }$ which might be observed soon in neutrino experiments.

  65. Lev Kofman, Andrei Linde, Alexei Starobinsky

    The theory of reheating of the Universe after inflation is developed. The transition from inflation to the hot Universe turns out to be strongly model-dependent and typically consists of several stages. Immediately after inflation the field $\phi$ begins rapidly rolling towards the minimum of its effective potential. Contrary to some earlier expectations, pa

  66. Yue-Hong Qian

    Submitted by the authors for the June 27-29 Princeton Conference. Questions should be directed to: qian@cfd.princeton.edu

  67. Liang-Xin Li, Bing-Lin Young

    Using spherical ansatz, we construct dual equations for non-abelian gauge fields in Minkowski space. The analytically continued instanton is shown to satisfy the dual equations but assumes a more ansatz. It is not the solution of MIT second order differential equation. The symmetries of the solution function space are examined. The relevant physics is review

  68. Liang-Xin Li, Bing-Lin Young

    Recently, MIT group found a numerical solution to non-abelian gauge fields which is shown to contain non-integer topological number. Using this fact, V.V.Khoze has argued that the vacuum theta angle is zero. Here, we study this in a complimentary way--its physical respect. The key point is MIT solution has an infinite action. Using this, we prove the vacuum

  69. S. Carlip, C. Teitelboim

    We discuss the quantum mechanics and thermodynamics of the (2+1)-dimensional black hole, using both minisuperspace methods and exact results from Chern-Simons theory. In particular, we evaluate the first quantum correction to the black hole entropy. We show that the dynamical variables of the black hole arise from the possibility of a deficit angle at the (E

  70. Bengt Edvardsson, Bertil Pettersson, Maryam Kharrazi, Bengt Westerlund

    We have determined chemical abundances and radial velocities for stars in the field of the zeta Sculptoris cluster. We find that the cluster metal deficiency previously found from UBV photometry is too high; the cluster overall metallicity, [Fe/H]=+0.24, is about 70% higher than the solar value. The chemical abundance pattern is unusual: the Ni/Fe ratio is s

  71. P. I. Tamborenea, S. Das Sarma

    Using the time-dependent-local-density-approximation (TDLDA) within a self-consistent linear response theory, we calculate the elementary excitation energies and the associated inelastic light-scattering spectra of a strongly coupled two-component plasma in a double-quantum well system with electron occupation of symmetric and antisymmetric subbands. We find

  72. Vladimir V. Usov

    One of the main properties of Wolf-Rayet (WR) stars is a very intense outflow of gas. No less than 40\% \ of WR stars belong to binary systems. Young massive O and B stars are the secondary components of such systems. OB stars also have an intense stellar wind. If the intensities of the stellar winds of WR and OB stars are more or less comparable or if the d

  73. Michael A. Doncheski, Sean Fleming, Michelangelo L. Mangano

    We present a calculation of the charm and gluon fragmentation contributions to inclusive $J/\psi$ and $\psi'$ production at large transverse momentum at the Tevatron. For $\psi$ production, we include both fragmentation directly into $\psi$ and fragmentation into $\chi_c$ followed by the radiative decay $\chi_c \to \psi + \gamma$. We find that fragmentation

  74. Ichiro Oda

    In this note we consider a stringy description of black hole horizon. We start with a nonlinear sigma model defined on a two dimensional Euclidean surface with background Rindler metric. By solving the field equations, we show that to the leading order the Bekenstein-Hawking formula of black hole entropy can be produced. We also point out a relation between

  75. Hiroshi Nakagawa, Shin'ichiro Nishizawa

    The important part of semantics of complex sentence is captured as relations among semantic roles in subordinate and main clause respectively. However if there can be relations between every pair of semantic roles, the amount of computation to identify the relations that hold in the given sentence is extremely large. In this paper, for semantics of Japanese

  76. Mark Burgess

    The paper describes a dynamical analogy for the renormalization group which leads to insights into its structure.

  77. B. K. Berger, D. Garfinkle, V. Swamy

    We propose to study the behavior of complicated numerical solutions to Einstein's equations for generic cosmologies by following the geodesic motion of a swarm of test particles. As an example, we consider a cylinder of test particles initially at rest in the plane symmetric Gowdy universe on $T^3 \times R$. For a circle of test particles in the symmetry pla

  78. Hisashi Kikuchi, Ernest Ma

    A new Majoron model is presented within the framework of the seesaw mechanism. Its Higgs sector consists of only doublet representations and the lepton-number violation takes place at the same scale of the electroweak symmetry breaking. This model is different from the singlet- or triplet-Majoron model in several respects: it is free from the \(\rho\)-parame

  79. Jonathan L. Rosner

    Schemes for fermion masses should predict elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. We review the freedom allowed by present experiments and how the parameter space will shrink in the next few years. In addition to experiments which directly affect CKM parameters, we discuss constraints arising from precise electroweak tests.

  80. Wei-Shu Hou, Gwo-Guang Wong

    We present new radiative mechanisms for generating Majorana neutrino masses, within an extension of the standard model that successfully generates radiative charged lepton masses, order by order, from heavy sequential leptons. Only the new sequential neutral lepton has a right-handed partner, and its Majorana mass provides the seed for Majorana neutrino mass

  81. Claudio Coriano'

    It has been shown, in the case of meson photoproduction, that the power-law falloff of these reactions can be described by lowest order (real) sum rules, at moderate momentum transfer. The phases of these processes, in this regime, are usually thought to be non-perturbative. In a sum rule framework, however, they can possibly be described by radiative correc

  82. Dean Prichard, James Theiler

    Extensions to various information theoretic quantities used for nonlinear time series analysis are discussed, as well as their relationship to the generalized correlation integral. It is shown that calculating redundancies from the correlation integral can be more accurate and more efficient than direct box counting methods. It is also demonstrated that many

  83. Dean Prichard

    The effect differencing has on the estimated correlation dimension of a nongaussian time series is discussed. Two different methods for generating surrogate data sets are compared. The results suggest that any filtering should be applied to both the raw and surrogate time series, otherwise spurious results can occur.

  84. D. L. Borden, V. A. Khoze, W. J. Stirling, J. Ohnemus

    The identification of the intermediate-mass Higgs process $\gamma\gamma\to H \to b \bar b$ will be one of the most important goals of a future photon linear collider. Potentially important backgrounds from the continuum $\gamma\gamma \to c \bar c, b \bar b$ leading-order processes can be suppressed by a factor $m_q^2/s$ by using polarized photon beams in the

  85. Charles W. Misner

    This paper begins with a short presentation of the Bianchi IX or ``Mixmaster'' cosmological model, and some ways of writing the Einstein equations for it. There is then an interlude describing how I came to a study of this model, and then a report of some mostly unpublished work from a Ph.\ D. thesis of D. M. (Prakash) Chitre relating approximate solutions t

  86. Matthias Troyer, Hirokazu Tsunetsugu, Diethelm Wuertz

    We have developed an improved version of the quantum transfer matrix algorithm. The extreme eigenvalues and eigenvectors of the transfer matrix are calculated by the recently developed look-ahead Lanczos algorithm for non-Hermitian matrices with higher efficiency and accuracy than by the power method. We have applied this method to the Heisenberg ladder. The

  87. Michael Gasser

    This paper describes a modular connectionist model of the acquisition of receptive inflectional morphology. The model takes inputs in the form of phones one at a time and outputs the associated roots and inflections. Simulations using artificial language stimuli demonstrate the capacity of the model to learn suffixation, prefixation, infixation, circumfixati

  88. Louis Crane, Igor B. Frenkel

    We propose a new mwthod of constructing 4D-TQFTs. The method uses a new type of algebraic structure called a Hopf Category. We also outline the construction of a family of Hopf categories related to the quantum groups, using the canonical bases.

  89. Jian Ma, C. Quitmann, R. J. Kelley, G. Margaritondo

    We present the first detailed angle-resolved photoemission evidence that there are two types of carriers that contribute to the photoemission superconducting condensate in $Bi_{2}Sr_{2}Ca_{1}Cu_{2}O_{8+x}$. Our data indicate that both itinerant and somewhat localized normal state carriers can contribute to the formation of Cooper pairs.

  90. K. Golec-Biernat, J. Kwiecinski, A. D. Martin, P. J. Sutton

    We calculate the transverse energy flow accompanying small $x$ deep-inelastic events and compare with recent data obtained at HERA. In the central region between the current jet and the remnants of the proton we find that BFKL leading $\ln(1/x)$ dynamics gives a distinctively large transverse energy distribution, in approximate agreement with recent data.

  91. Nicola N. Khuri

    We discuss the importance of measuring $\rho= ReF/ImF$ at LHC to test the forward dispersion relations and local QFT. It is pointed out that at LHC we can reach a short distance domain that has not been pre-explored by QED. This is in contrast with all previous tests of the dispersion relations. We argue that the most likely property of QFT to fail is polyno

  92. Wei Chen, Chigak Itoi

    We reply a Comment (hep-th/xxx) on our recent paper published in Phys Rev Lett 72 (1994) 2527-2530. We point out that the author of the Comment overlooks the highly non-trivial Chern-Simons interactions and his hand-waving arguments are totally groundless.

  93. Alice Rogers, Mark Langer

    A new $(1,1)$-dimensional super vector bundle which exists on any super Riemann surface is described. Cross-sections of this bundle provide a new class of fields on a super Riemann surface which closely resemble holomorphic functions on a super Riemann surface, but which (in contrast to the case with holomorphic functions) form spaces which have a well defin

  94. Jose L. Cortes, Mikhail S. Plyushchay

    The minimal (reduced) and extended canonical formulations for (2+1)-dimensional fractional spin particles are considered. We investigate the relationship between them, clearing up the meaning of the coordinates for such particles, and analyse the related question of correlation between spin and momentum. The classical lagrangian corresponding to the extended

  95. Iosif Lapidus, Luciano Nobili, Roberto Turolla

    We present estimates for the accretion rates in 13 X--ray bursting sources which exhibit photospheric expansion, basing on theoretical models of stationary, radiatively driven winds from neutron stars. The relatively high values obtained, $\Mdot_{acc}\magcir 10^{-9} \MS$, are in accordance with theoretical limits for unstable helium burning, and, at the same

  96. Luciano Nobili, Roberto Turolla, Iosif Lapidus

    A model for stationary, radiatively driven winds from X--ray bursting neutron stars is presented. General relativistic hydrodynamical and radiative transfer equations are integrated from the neutron star surface outwards, taking into account for helium nuclear burning in the inner, dense, nearly hydrostatic shells. Radiative processes include both bremsstrah

  97. D. Tz. Stoyanov

    A general functional definition of the infinite dimensional quantum $R$-matrix satisfying the Yang-Baxter equation is given. A procedure for the extracting a finite dimensional $R$-matrix from the general definition is demonstrated in a particular case when the group $SU(2)$ takes place.

  98. F. Vissani, A. Yu. Smirnov

    There are several indications that the Majorana masses of the right-handed neutrino components, $M_R,$ are at the intermediate scale: $M_R\sim (10^{10}-10^{12})$ GeV or even lighter. The renormalization effects due to large Yukawa couplings of neutrinos from region of momenta $M_R \ltap q \ltap M_G$ are studied in the supersymmetric standard model. It is sho

  99. K. Ohta, H. Suzuki

    We investigate the spin $1/2$ fermions on quantum two spheres. It is shown that the wave functions of fermions and a Dirac Operator on quantum two spheres can be constructed in a manifestly covariant way under the quantum group $SU(2)_q$. The concept of total angular momentum and chirality can be expressed by using $q$-analog of Pauli-matrices and appropriat

  100. F. A. Berends, R. Pittau, R. Kleiss

    The implementation of QED initial-state radiative corrections in the process of four-fermion production at LEP200 and higher-energy e+e- colliders is discussed. Because of the presence of charged-current processes, this is a nontrivial problem, and we compare our approach with other existing treatments. We describe the Monte Carlo algorithm used for the gene