Research archive
arXiv papers from August 1992
The most recent 100 records published that month. Open any paper for its original abstract, citation metadata, related research, and reading tools.
A. V. Balatsky, B. L. Altshuler
Spin-orbit interaction produces persistent spin and mass currents in the ring via the Aharonov-Casher effect. The experiment in $^3He-A_1$ phase, in which this effect leads to the excitation of mass and spin supercurrent is proposed.
- Electromagnetic response of a static vortex line in a type-II superconductor : a microscopic studycond-mat
Boldizsar Janko, Joel D. Shore
The electromagnetic response of a pinned Abrikosov fluxoid is examined in the framework of the Bogoliubov-de Gennes formalism. The matrix elements and the selection rules for both the single photon (emission - absorption) and two photon (Raman scattering) processes are obtained. The results reveal striking asymmetries: light absorption by quasiparticle pair
C. P. Burgess, James M. Cline, Markus Luty
We show how a 17 keV neutrino, the solar neutrino problem, and the atmospheric muon-neutrino deficit could all be the low-energy residues of the same pattern of lepton-number breaking at and above the weak scale, with no requirement for fine-tuning a symmetry-breaking scale at lower energies. Talk given at ``Beyond the Standard Model III'', Carleton Universi
A. Matsuo
A Fock representation of the quantum affine algebra $U_q(\widehat{\sl}_2)$ is constructed by three bosonic fields for an arbitrary level with the help of the Drinfeld realization.
Yu. L. Kalinovsky, L. Kaschluhn
In this paper we consider the bilocal field approach for $QCD$. We obtain a bilocal effective meson action with a potential kernel given in relativistic covariant form. The corresponding Schwinger--Dyson and Bethe--Salpeter equations are investigated in detail. By introducing weak interactions into the theory we study heavy meson properties as decay constant
K. S. Babu, R. R. Volkas
In the minimal Standard Model (MSM) with three generations of quarks and leptons, neutrinos can have tiny charges consistent with electromagnetic gauge invariance. There are three types of non-standard electric charge, given by $Q_{st} + \epsilon(L_i - L_j)$, where $i, j = e, \mu, \tau$ $(i \neq j)$, $Q_{st}$ is standard electric charge, $L_i$ is a family-le
Tomás Ortín
We present a generalization of the $U(1)^{2}$ charged dilaton black holes family whose main feature is that both $U(1)$ fields have electric and magnetic charges, the axion field still being trivial. We show the supersymmetry of these solutions in the extreme case, in which the corresponding generalization of the Bogomolnyi bound is saturated and a naked sin
Atsushi Yamagata
We study the interfacial adsorption phenomena of the three-state ferromagnetic Potts model on the simple cubic lattice by the Monte Carlo method. Finite-size scaling analyses of the net-adsorption yield the evidence of the phase transition being of first-order and $k_{\rm B} T_{\rm C} / J = 1.8166 (2)$.
- The Constraint for the Lowest Landau Level and the Effective Field Theory Approach for the Fractional Quantum Hall Systemcond-mat
Zhong-Shui Ma, Zhao-Bin Su
By applying the Dirac quantization method, we build the constraint that all electrons are in the lowest Landau level into the Chern-Simons field theory approach for the fractional quantum Hall system and show that the constraint can be transmuted from hierarchy to hierarchy. For a finite system, we derive that the action for each hierarchy can be split into
Shmuel Fishmen, Yonathan Shapir, Xiang-Rong Wang
The magnetic field effects on lattice wavefunctions of Hofstadter electrons strongly localized at boundaries are studied analytically and numerically. The exponential decay of the wavefunction is modulated by a field dependent amplitude J(t) which depends sensitively on the value of alpha (the magnetic flux per plaquette in units of a flux quantum, t is the
Amit Giveon, Andrea Pasquinucci
A large class of cosmological solutions (of the Einstein equations) in string theory, in the presence of Maxwell fields, is obtained by $O(d,d)$ transformations of simple backgrounds with $d$ toroidal isometries. In all the examples in which we find a (closed) expanding universe, such that the universe admits a smooth, complete initial value hypersurface, a
J. M. Figueroa-O'Farrill, J. Mas, E. Ramos
We chart out the landscape of $\Winfty$-type algebras using $\Wkpq$---a recently discovered one-parameter deformation of $\W_{\rm KP}$. We relate all hitherto known $\Winfty$-type algebras to $\Wkpq$ and its reductions, contractions, and/or truncations at special values of the parameter.
Jong H. Kung
A consequence of non-Gaussian perturbations on the Sachs-Wolfe effect is studied. For a particular power spectrum, predicted Sachs-Wolfe effects are calculated for two cases: Gaussian (random phase) configuration, and a specific kind of non-Gaussian configuration. We obtain a result that the Sachs-Wolfe effect for the latter case is smaller when each tempera
- Canonical Quantization of the Liouville Theory, Quantum Group Structures, and Correlation Functionshep-th
Gerhard Weigt
We describe a self-consistent canonical quantization of Liouville theory in terms of canonical free fields. In order to keep the non-linear Liouville dynamics, we use the solution of the Liouville equation as a canonical transformation. This also defines a Liouville vertex operator. We show, in particular, that a canonical quantized conformal and local quant
E. H. Simmons, R. S. Chivukula, S. B. Selipsky
Extended technicolor theories generate potentially large corrections to the $\Zbb$ vertex. These can be observed in current experiments at LEP.
J. Chyla, J. Rames
The validity of local parton-hadron duality within the framework of HERWIG and JETSET event generators is investigated. We concentrate on ${\rm e}^{+}{\rm e}^{-}$ annihilations in LEP 2 energy range as these interactions provide theoretically the cleanest condition for the discussion of this concept.
M. -C. Chu, J. M. Grandy, S. Huang, J. W. Negele
The first exploratory calculations of QCD vacuum correlation functions on a lattice are reported. Qualitative agreement with phenomenological results is obtained in channels for which experimental data are available, and these correlation functions are shown to be useful in exploring approximations based on sum rules and interacting instantons.
B. de Wit, A. K. Tollsten, H. Nicolai
We study non-linear sigma models with N local supersymmetries in three space-time dimensions. For N=1 and 2 the target space of these models is Riemannian or Kahler, respectively. All N>2 theories are associated with Einstein spaces. For N=3 the target space is quaternionic, while for N=4 it generally decomposes into two separate quaternionic spaces, associa
Francois Gieres, Stefan Theisen
We study superdifferential operators of order $2n+1$ which are covariant with respect to superconformal changes of coordinates on a compact super Riemann surface. We show that all such operators arise from super M\"obius covariant ones. A canonical matrix representation is presented and applications to classical super W algebras are discussed.
V. Spiridonov
Affine transformations (dilatations and translations) are used to define a deformation of one-dimensional $N=2$ supersymmetric quantum mechanics. Resulting physical systems do not have conserved charges and degeneracies in the spectra. Instead, superpartner Hamiltonians are $q$-isospectral, i.e. the spectrum of one can be obtained from another (with possible
S. Khokhlachev, Yu. Makeenko
We propose to induce QCD by fermions in the adjoint representation of the gauge group SU(N_c) on the lattice. We consider various types of lattice fermions: chiral, Kogut--Susskind and Wilson ones. Using the mean field method we show that a first order large-N phase transition occurs with decreasing fermion mass. We conclude, therefore, that adjoint fermions
W. Broniowski, T. D. Cohen
Linear response theory for SU(2) hedgehog soliton models is developed.
- Response of nucleons to external probes in hedgehog models: I. Electromagnetic polarizabilitieshep-ph
W. Broniowski, T. D. Cohen
Electromagnetic polarizabilities of the nucleon are analyzed in a hedgehog model with quark and meson degrees of freedom.
Sinya Aoki, Andreas Gocksch, Yue Shen
We study numerically the SU(2) Kazakov-Migdal model of `induced QCD'. In contrast to our earlier work on the subject we have chosen here {\it not} to integrate out the gauge fields but to keep them in the Monte Carlo simulation. This allows us to measure observables associated with the gauge fields and thereby address the problem of the local $Z_2$ symmetry
B. Harms, Y. Leblanc
We extend the considerations of a previous paper on black hole statistical mechanics to the case of black extended objects such as black strings and black membranes in 10-dimensional space-time. We obtain a general expression for the Euclidean action of quantum black p-branes and derive their corresponding degeneracy of states. The statistical mechanics of a
- Electronic and structural properties of GaN by the full-potential LMTO method : the role of the $d$ electronscond-mat
Vincenzo Fiorentini, Michael Methfessel, Matthias Scheffler
The structural and electronic properties of cubic GaN are studied within the local density approximation by the full-potential linear muffin-tin orbitals method. The Ga $3d$ electrons are treated as band states, and no shape approximation is made to the potential and charge density. The influence of $d$ electrons on the band structure, charge density, and bo
David H Lyth, Andrew R Liddle
We analyse the implications for inflationary models of the cosmic microwave background (cmb) anisotropy measured by COBE. Vacuum fluctuations during inflation generate an adiabatic density perturbation, and also gravitational waves. The ratio of these two contributions to the cmb anisotropy is given for an arbitrary slow-roll inflaton potential. Results from
Pierre Le Doussal, Leo Radzihovsky
We study $D$-dimensional polymerized membranes embedded in $d$ dimensions using a self-consistent screening approximation. It is exact for large $d$ to order $1/d$, for any $d$ to order $\epsilon=4-D$ and for $d=D$. For flat physical membranes ($D=2,d=3$) it predicts a roughness exponent $\zeta=0.590$. For phantom membranes at the crumpling transition the si
M. Urban, A. Bouquet, B. Degrange, P. Fleury
There is a growing interest in the possibility that dark matter could be formed of weakly interacting particles with a mass in the 100 GeV - 2 TeV range, and supersymmetric particles are favorite candidates. If they constitute the dark halo of our Galaxy, their mutual annihilations produce energetic gamma rays that could be detected using existing atmospheri
Gunnar S. Bali, Klaus Schilling
We present new results on the static qq-potential from high statistics simulations on 32^4 and smaller lattices, using the standard Wilson beta = 6.0, 6.4, and 6.8. Within our statistical errors we do not observe any finite size effects affecting the potential values, on varying the spatial lattice extent from 0.9fm up to 3.3fm. We are able to see and quanti
Pierre van Baal, R. E. Cutkosky
In this contribution to the proceedings we will describe some of the details for constructing the Gribov horizon and the boundary of the fundamental modular domain, when restricting to some low energy modes of pure SU(2) gauge theory in a spherical spatial geometry. The fundamental domain is a one-to-one representation of the set of gauge invariant degrees o
Ralph Blumenhagen
We investigate extensions of the N=2 super Virasoro algebra by one additional super primary field and its charge conjugate. Using a supersymmetric covariant formalism we construct all N=2 super W-algebras up to spin 5/2 of the additional generator. Led by these first examples we close with some conjectures on the classification of N=2 ${\cal SW}(1,\Dt)$ alge
Alain Billoire
I present results of simulations of the q=10 and q=20 2-d Potts models in the transition region. The asymptotic finite size behavior sets in only for extremely large lattices. We learn from this simulation that finite size scaling cannot be used to decide that a transition is first order.
Robert Perret
By extending the concept of \mc, I introduce a dual formulation of (classical) nonlinear extensions of the \vir\ algebra. This dual formulation is closely related to three dimensional actions which are analogous to a \cs\ action. I present an explicit construction in terms of superfields of the $N=2$ super \wfour.
Michio Jimbo, Tetsuji Miwa, Yasuhiro Ohta
The restricted solid-on-solid models in the anti-ferromagnetic regime is studied in the framework of quantum affine algebras. Following the line developed recently for vertex models, a representation theoretical picture is presented for the structure of the space of states. The local operators and the creation/annihilation operators of quasi-particles are de
Makoto Idzumi, Kenji Iohara, Michio Jimbo, Tetsuji Miwa
We study the higher spin anologs of the six vertex model on the basis of its symmetry under the quantum affine algebra $U_q(\slth)$. Using the method developed recently for the XXZ spin chain, we formulate the space of states, transfer matrix, vacuum, creation/annihilation operators of particles, and local operators, purely in the language of representation
Sandip K. Chakrabarti
We show that under certain astrophysical conditions a binary system consisting of two compact objects can be stabilized against indefinite shrinking of orbits due to the emission of gravitational radiation. In this case, the lighter binary companion settles down to a stable orbit when the loss of the angular momentum due to gravitational radiation becomes eq
Derek B. Leinweber, Terrence Draper, R. M. Woloshyn
The electromagnetic properties of the SU(3)-flavor baryon decuplet are examined within a lattice simulation of quenched QCD. Electric charge radii, magnetic moments, and magnetic radii are extracted from the E0 and M1 form factors. Preliminary results for the E2 and M3 moments are presented giving the first model independent insight to the shape of the quark
Geoffrey T. Bodwin, Eric Braaten, Tzu Chiang Yuan, G. Peter Lepage
We calculate the decay rates of $B$ mesons into P-wave charmonium states using new factorization formulas that are valid to leading order in the relative velocity of the charmed quark and antiquark and to all orders in the running coupling constant of QCD. We express the production rates for all four P states in terms of two nonperturbative parameters, the d
- The Lax Operator Approach for the Virasoro and the W-Constraints in the Generalized KdV Hierarchyhep-th
Shibaji Roy, Sudhakar Panda
We show directly in the Lax operator approach how the Virasoro and W-constraints on the $\tau$-function arise in the $p$-reduced KP hierarchy or generalized KdV hierarchy. In partiacular, we consider the KdV and Boussinesq hierarchy to show that the Virasoro and W-constraints follow from the string equation by expanding the ``additional symmetry" operator in
Thomas D. Cohen, Wojciech Broniowski
Hedgehog model predictions for the leading nonanalytic behavior (in $m^{2}_{\pi }$) of certain observables are shown to agree with the predictions of chiral perturbation theory up to an overall factor which depends on the operator. This factor can be understood in terms of contributions of the $\Delta$ isobar in chiral loops. These physically motivated contr
W. Broniowski, T. D. Cohen
Nonminimal substitution terms in electroweak currents are studied in effective chiral soliton models. It is found that the terms describing the structure of the pion lead to sizable effects in form factors and polarizabilities of the nucleon.
Ted Hsu
This paper is relevant to the recent optical transmission experiments of Karrai et al. for vortices in high Tc superconductors. We begin with a substantial review and introduction. The microscopic response of vortices is calculated from the Bogoliubov-deGennes equation, including an equation of motion and conductivity. We find that the expected resonant dipo
E. Kiritsis, C. Kounnas, D. Lust
A large class of new 4-D superstring vacua with non-trivial/singular geometries, spacetime supersymmetry and other background fields (axion, dilaton) are found. Killing symmetries are generic and are associated with non-trivial dilaton and antisymmetric tensor fields. Duality symmetries preserving N=2 superconformal invariance are employed to generate a larg
Stephen D. Ellis, Zoltan Kunszt, Davison E. Soper
Results from the study of hadronic jets in hadron-hadron collisions at order $\alpha_s^3$ in perturbation theory are presented. The focus is on various features of the internal structure of jets. The numerical results of the calculation are compared with data where possible and exhibit reasonable agreement.
M. A. Doncheski, R. W. Robinett, L. Weinkauf
We examine the spin-dependence of standard model Higgs boson production at large transverse momentum via the processes $gg \rightarrow gH^0$, $qg \rightarrow qH^0$, and $q\overline{q} \rightarrow gH^0$. The partonic level spin-spin asymmetries ($\hat{a}_{LL}$) for these processes are large at SSC/LHC energies.
B. Sriram Shastry
In this article, I discuss W.Kohn's criterion for a metal insulator transition, within the framework of a one band Hubbard model. This and related ideas are applied to 1-dimensional Hubbard systems, and some intersting miscellaneous results discussed. The Jordan Wigner transformation converting the two species of fermions to two species of hardcore bosons is
Elizabeth Jenkins, Aneesh V. Manohar, Mark B. Wise
In the large $N_c$ limit, the $\Lambda_b$ and $\Lambda_c$ can be treated as bound states of chiral solitons and mesons containing a heavy quark. We show that the soliton and heavy meson are bound in an attractive harmonic oscillator potential. The Isgur-Wise function for $\Lambda_b\rightarrow\Lambda_c\, e^-\,\bar\nu_e$ decay is computed in the large $N_c$ li
Satoshi Mizuta, Masahiro Yamaguchi
We calculate the relic abundance of Higgsino-dominant lightest superparticles, taking account of coannihilations with the superparticles which are almost degenerate with the lightest one. We show that their relic abundance is reduced drastically by the coannihilation processes and hence they are cosmologically of no interest.
- Dimerization and Energy-Level Structures in Fullerene Tubules Investigated with an Electron-Phonon Modelcond-mat
Kikuo Harigaya, Mitsutaka Fujita
Possible dimerization patterns and electronic structures in fullerene tubules as the π-conjugated systems are studied with the extended Su-Schrieffer- Heeger model. We assume various lattice geometries, including helical and nonhelical tubules, and tubules with end caps. The model is solved for the half-filling case of π-electrons. (1) When the undimerized s
Y-h. Taguchi, Hideki Takayasu
Fully developed turbulence is analised with the lattice model employing vortex tube representation which is introduced recently by the authors. Several characteric features observed in experiments and direct numeric integrations are reproduced. Not only Kolmogorov's inertial range is observed, but also several local probability distribution functions are
Y-h. Taguchi, Hideki Takayasu
Simulations of vortex tube dynamics reveal that the non-Gaussian nature of turbulent fluctuation originates in the effect of random advection. A similar non-Gaussian distribution is found numerically in a simplified statistical model of random advection. An analytical solution is obtained in the mean-field case.
Leandros Perivolaropoulos
We construct a simple analytical model to study the effects of cosmic strings on the microwave background radiation. Our model is based on counting random multiple impulses inflicted on photon trajectories by the string network between the time of recombination and today. We construct the temperature auto-correlation function and use it to obtain the effecti
Zygmunt Lalak, Krzysztof Meissner, Jacek Pawełczyk
It is shown that quantum fluctuations due to a nontrivial gravitational background in the flat radiation dominated universe can play an important cosmological role generating nonvanishing cosmological global charge, e.g. baryon number, asymmetry. The explicit form of the fluctuations at vacuum and at finite temperature is given. Implications for particle phy
Michael Fowler, Joseph A. Minahan
Using a formalism developed by Polychronakos, we explicitly construct a set of invariants of the motion for the Haldane-Shastry $SU(N)$ chain.
R. Holman, S. D. H. Hsu, T. Vachaspati, R. Watkins
We investigate the stability of the electroweak Z-string at high temperatures. Our results show that while finite temperature corrections can improve the stability of the Z-string, their effect is not strong enough to stabilize the Z-string in the standard electroweak model. Consequently, the Z-string will be unstable even under the conditions present during
S. Govindarajan, T. Jayaraman, V. John
We compute N-point correlation functions of pure vertex operator states(DK states) for minimal models coupled to gravity. We obtain agreement with the matrix model results on analytically continuing in the numbers of cosmological constant operators and matter screening operators. We illustrate this for the cases of the $(2k-1,2)$ and $(p+1,p)$ models.
H. Rieger
The number $\langle N_s\rangle$ of solutions of the equations of Thouless, Anderson and Palmer for p--spin interaction spin glass models is calculated. Below a critical temperature $T_c$ this number becomes exponentially large, as it is in the SK--model ($p=2$). But in contrast to this, for any $p>2$ the factor $\alpha(T)=N^{-1} \ln\langle N_s\rangle$ jumps
- The Last Three Minutes: Issues in Gravitational Wave Measurements of Coalescing Compact Binariesastro-ph
Curt Cutler, Theocharis A. Apostolatos, Lars Bildsten, Lee Samuel Finn
Gravitational-wave interferometers are expected to monitor the last three minutes of inspiral and final coalescence of neutron star and black hole binaries at distances approaching cosmological, where the event rate may be many per year. Because the binary's accumulated orbital phase can be measured to a fractional accuracy $\ll 10^{-3}$ and relativistic eff
K. Kamimura, T. Fukuyama
The action of Ashtekar gravity have been found by Cappovilla, Jacobson and Dell. It does not depend on the metric nor the signature of the space-time. The action has a similar structure as that of a massless relativistic particle. The former is naturally generalized by adding a term analogous to a mass term of the relativistic particle. The new action posses
Peter G. O. Freund, Anton V. Zabrodin
The S-matrices for the scattering of two excitations in the XYZ model and in all of its SU(n)-type generalizations are obtained from the asymptotic behavior of Kerov's generalized Hall-Littlewood polynomials. These physical scattering processes are all reduced to geometric s-wave scattering problems on certain quantum-symmetric spaces, whose zonal spherical
Peter Cho
The formalism and applications of chiral perturbation theory for hadrons containing a single heavy quark are discussed. We emphasize the utility of working directly with the velocity dependent ``super'' fields which appear in the chiral Lagrangian and whose interactions manifestly preserve heavy quark spin symmetry rather than their individual spin component
Sandip K. Chakrabarti, Pankaj S. Joshi
Naked singularities appear naturally in dynamically evolving solutions of Einstein equations involving gravitational collapse of radiation, dust and perfect fluids, provided the rate of accretion is less than a critical value. We propose that the gamma-ray bursters (GRBs) are examples of these naked singularity solutions. For illustration, we show that accor
E. C. Marino
The order-disorder duality structure is exploited in order to obtain a quantum description of anyons and vortices in: a) the Maxwell theory; b) the Abelian Higgs Model; c) the Maxwell-Chern-Simons theory; d) the Maxwell-Chern-Simons-Higgs theory. A careful construction of a charge bearing order operator($\sigma$) and a magnetic flux bearing disorder operator
P. Martin, Herbert Saleur
We study representations of Temperley-Lieb algebras associated with the transfer matrix formulation of statistical mechanics on arbitrary lattices. We first discuss a new hyperfinite algebra, the Diagram algebra $D_{\underline{n}}(Q)$, which is a quotient of the Temperley-Lieb algebra appropriate for Potts models in the mean field case, and in which the alge
S. Dimopoulos, L. J. Hall, S. Raby
A framework for predicting charged fermion masses in supersymmetric grand unified theories is extended to make predictions in the neutrino sector. Eight new predictions are made, and their relevance to neutrino oscillation experiments and the solar neutrino problem are discussed.
J. E. Cieza Montalvo, O. J. P. Eboli
We study the signals for composite vector leptoquarks in $e^+ e^-$ colliders (LEP II, NLC, and CLIC) through their effects on the production of jet pairs, as well as their single and pair productions. We also analyze their production in $\gamma e$ and $\gamma\gamma$ collisions.
Fiorenzo Bastianelli, Peter van Nieuwenhuizen
The 1-loop anomalies of a d-dimensional quantum field theory can be computed by evaluating the trace of the regulated path integral jacobian matrix, as shown by Fujikawa. In 1983, Alvarez-Gaum\'e and Witten observed that one can simplify this evaluation by replacing the operators which appear in the regulator and in the jacobian by quantum mechanical operato
Timothy Hollowood, J. Luis Miramontes
The tau-function formalism for a class of generalized ``zero-curvature'' integrable hierarchies of partial differential equations, is constructed. The class includes the Drinfel'd-Sokolov hierarchies. A direct relation between the variables of the zero-curvature formalism and the tau-functions is established. The formalism also clarifies the connection betwe
Niall MacKay, William McGhee
Using Hirota's method, solitons are constructed for affine Toda field theories based on the simply-laced affine algebras. By considering automorphisms of the simply-laced Dynkin diagrams, solutions to the remaining algebras, twisted as well as untwisted, are deduced.
Yoshiaki Tanii
Quantization of the dilaton gravity in two dimensions is discussed by a semiclassical approximation. We compute the fixed-area partition function to one-loop order and obtain the string susceptibility on Riemann surfaces of arbitrary genus. Our result is consistent with the approach using techniques of conformal field theories.
S. Gupta, A. Irbaeck
We report tests of finite-size scaling ansatzes in the low temperature phase of the two-dimensional Ising model. For moments of the magnetisation density, we find good agreement with the new ansatz of Borgs and Koteck\'y, and clear evi consequences of the convexity of the free energy are not adequately treated in either of these approaches.\lb {\it Keywords}
A. A. Migdal
The problems with the $Z_N$ symmetry breaking in the induced QCD are analyzed. We compute the Wilson loops in the strong coupling phase, but we do not find the $Z_N$ symmetry breaking, for arbitrary potential. We suggest to bypass this problem by adding to the model a heavy fermion field in a fundamental representation of $ SU(N) $. Remarkably, the model sti
Rick Miranda
Let S be a torsion section of an elliptic surface with only I_n fibers. This article addresses the question: which components of singular fibers can S pass through? We give necessary criteria for the "component numbers", and show an equidistribution result for torsion sections of prime order.
Andrzej Czarnecki, Sacha Davidson
Using dimensional regularization for both infrared and ultraviolet divergences, we confirm that the QCD corrections to the decay width $\Gamma(t\to H^+b)$ are equal to those to $\Gamma(t\to W^+b)$ in the limit of a large $t$ quark mass.
James. M. Gelb, Ben-Ami Gradwohl, Joshua A. Frieman
The cold dark matter (CDM) model of structure formation, normalized on large scales, leads to excessive pairwise velocity dispersions on small scales. In an attempt to circumvent this problem, we study three scenarios (all with $\Omega=1$) which have more large-scale power and less small-scale power than the CDM model: 1) an admixture of cold and hot dark ma
J. A. Dixon, M. J. Duff, J. C. Plefka
According to string/fivebrane duality, the Green-Schwarz factorization of the $D=10$ spacetime anomaly polynomial $I_{12}$ into $X_4\, X_8$ means that just as $X_4$ is the anomaly polynomial of the $d=2$ string worldsheet so $X_8$ should be the anomaly polynomial of the $d=6$ fivebrane worldvolume. To test this idea we perform a fivebrane calculation of $X_8
I. Kostov
The models of triangulated random surfaces embedded in (extended) Dynkin diagrams are formulated as a gauge-invariant matrix model of Weingarten type. The double scaling limit of this model is described by a collective field theory with nonpolynomial interaction. The propagator in this field theory is essentially two-loop correlator in the corresponding stri
I. I. Kogan, A. Morozov, G. W. Semenoff, N. Weiss
We analyze the scalar field sector of the Kazakov--Migdal model of induced QCD. We present a detailed description of the simplest one dimensional {($d$$=$$1$)} model which supports the hypothesis of wide applicability of the mean--field approximation for the scalar fields and the existence of critical behaviour in the model when the scalar action is Gaussian
Elizabeth Jenkins, Aneesh V. Manohar
The $\Sigma_c^*-\Sigma_c$ and $\Sigma_b^*-\Sigma_b$ hyperfine mass splittings are computed in the Skyrme model. The hyperfine splittings are suppressed by both $1/N_c$ and by $1/m_Q$, where $N_c$ is the number of colors and $m_Q$ is the mass of the heavy quark. The $\Sigma_c$, $\Sigma_c^*$, $\Sigma_b$, $\Sigma_b^*$, and $\Lambda_b$ masses are predicted in te
- Renormalization Group Coefficients for the Un-Truncated Derivative Expansion in Effective Field Theoryhep-ph
Vineer Bhansali
We investigate the renormalization of ``nonlocal" interactions which arise as an infinite sum of higher derivative interactions in an effective field theory. Using dimensional regularization with minimal subtraction in a general scalar field theory, we write an integro-differential renormalization group equation for the most general graph at one loop order.
William A. Ponce, Arnulfo Zepeda, Ricardo Gaitan Lozano
In the context of the left-right symmetric gauge group [SU(6)]$^3\times$ Z$_3$ which unifies nongravitational forces with flavors, we analyze the generational seesaw mechanism. At tree level we get m$_{\nu_\tau}\sim$m$_{\nu_\mu}\sim$M$^2_L$/M$_H$, m$_{\nu_e}=0$, where M$_L\sim10^2$ GeVs and M$_H\ge 100$ TeVs is the mass scale at which the horizontal interact
Jan Louis
The structure of differential equations as they appear in special \K\ geometry of $N=2$ supergravity and $(2,2)$ vacua of the heterotic string is summarized. Their use for computing couplings in the low energy effective Lagrangians of string compactifications is outlined. (Talk presented at the Workshop on String Theory, April 8--10, 1992, Trieste, Italy)
Simon Hands, Aleksandar Kocic, John B. Kogut
Four-fermi models in dimensionality $2<d<4$ exhibit an ultra-violet stable renormalization group fixed point at a strong value of the coupling constant where chiral symmetry is spontaneously broken. The resulting field theory describes relativistic fermions interacting non-trivially via exchange of scalar bound states. We calculate the $O(1/N_f)$ corrections
Michel Carreau
A free non-relativistic particle moving in two dimensions on a half-plane can be described by self-adjoint Hamiltonians characterized by boundary conditions imposed on the systems. The most general boundary condition is parameterized in terms of the elements of an infinite-dimensional matrix. We construct the Brownian functional integral for each of these se
S. J. Hands, A. Kocic, J. B. Kogut, R. L. Renken
Non-compact lattice QED with two flavors of light dynamical quarks is simulated on $16^4$ lattices, and the chiral condensate, monopole density and susceptibility and the meson masses are measured. Data from relatively high statistics runs at relatively small bare fermion masses of 0.005, 0.01, 0.02 and 0.03 (lattice units) are presented. Three independent m
H. Rieger
An algoritm for the simulation of the 3--dimensional random field Ising model with a binary distribution of the random fields is presented. It uses multi-spin coding and simulates 64 physically different systems simultaneously. On one processor of a Cray YMP it reaches a speed of 184 Million spin updates per second. For smaller field strength we present a ve
B. Grossmann, M. L. Laursen, T. Trappenberg, U. -J. Wiese
The reduced tension $\sigma_{cd}$ of the interface between the confined and the deconfined phase of $SU(3)$ pure gauge theory is related to the finite size effects of the first transfer matrix eigenvalues. A lattice simulation of the transfer matrix spectrum at the critical temperature $T_c = 1/L_t$ yields $\sigma_{cd} = 0.139(4) T_c^2$ for $L_t = 2$. We fou
- The Hyperfine Splitting in Charmonium: Lattice Computations Using the Wilson and Clover Fermion Actionshep-lat
UKQCD Collaboration, C. R. Allton, C. T. Sachrajda, S. P. Booth
We compute the hyperfine splitting $m_{J/\psi}-m_{\eta_c}$ on the lattice, using both the Wilson and $O(a)$-improved (clover) actions for quenched quarks. The computations are performed on a $24^3\times48$ lattice at $\beta = 6.2$, using the same set of 18 gluon configurations for both fermion actions. We find that the splitting is 1.83\err{13}{15} times lar
H. Neuberger, U. M. Heller, M. Klomfass, P. Vranas
Older lattice work exploring the Higgs mass triviality bound is briefly reviewed. It indicates that a strongly interacting scalar sector in the minimal standard model cannot exist; on the other hand low energy QCD phenomenology might be interpreted as an indication that it could. We attack this puzzle using the $1/N$ expansion and discover a simple criterion
J Liu, K Ismail, KY Lee, JM Hong
A new electron focusing effect has been discovered in small single and coupled GaAs/AlGaAs rings. The focusing in the single ring is attributed solely to internal orbits. The focusing effect allows the ring to be used as a small mass spectrometer. The focusing causes peaks in the magnetoresistance at low fields, and the peak positions were used to study the
Enrico Onofri
We consider the design of a non-local MonteCarlo algorithm for $SU(3)$ lattice systems according to the idea of {\em embedding} the degrees of freedom corresponding to the center of the group $Z(3)$. As a crucial ingredient to reach this goal, we present a practical implementation of a cluster algorithm for $Z(3)$ systems with general random pair interaction
Y. Achiman, A. Lukas
All experimental results concerning possible neutrino oscillations are naturally and simultaneously accounted for in an $E_6$ GUT model. The fermionic mass matrices are dictated by the symmetry breaking and specific radiative corrections and not by the use of ``Ans\"atze'' or discrete symmetries.
A. Garcia, R. F. Lax
Let $X$ denote an integral, projective Gorenstein curve over an algebraically closed field $k$. In the case when $k$ is of characteristic zero, C. Widland and the second author have defined Weierstrass points of a line bundle on $X$. In the first section, this definition is extended to linear systems in arbitrary characteristic. This definition may be viewed
R. Brandenberger, T. Prokopec, V. Mukhanov
We derive a formula for the nonequilibrium entropy of a classical stochastic field in terms of correlation functions of this field. The formalism is then applied to define the entropy of gravitational perturbations (both gravitational waves and density fluctuations). We calculate this entropy in a specific cosmological model (the inflationary Universe) and f
Vladimir G. Pestov
We survey the present trends in theory of universal arrows to forgetful functors from various categories of topological algebra and functional analysis to categories of topology and topological algebra. Among them are free topological groups, free locally convex spaces, free Banach-Lie algebras, and much more. An accent is put on relationship of those constr
Yannick Meurice
It is proved that for a system of spins $\sigma _i = \pm 1$ having an interaction energy $-\sum K_{ij} \sigma _i \sigma _j $ with all the $K_{ij}$ strictly positive,one can construct a dual formulation by associating a dual spin $S_{ijk} = \pm 1$ to each triplet of distinct sites $i,j$ and $k$. The dual interaction energy reads $-\sum _{(ij)} D_{ij} \prod _{
- Remarks Concerning Polyakov's Conjecture for the 3D Ising Model and the Hierarchical Approximationhep-th
Yannick Meurice
We consider the possibility of using the hierarchical approximation to understand the continuum limit of a reformulation of the 3D Ising model initiated by Polyakov. We introduce several new formulations of the hierarchical model using dual or fermionic variables. We discuss several aspects of the renormalization group transformation in terms of these new va
D. M. Gitman, A. V. Saa
A generalization of the pseudoclassical action of a spinning particle in the presence of an anomalous magnetic momentum is given. The action is written in reparametrization and supergauge invariant form. The Dirac quantization, based on the Hamiltonian analyses of the model, leads to the Dirac-Pauli equation for a particle with an anomalous magnetic momentum
M. R. Norman
A method is derived for calculating the pairing kernel in exchange mediated superconductors including matrix element effects. Various models for the interaction vertex are considered, including spin exchange, orbital exchange, and quadrupolar exchange. As an example, this formalism is applied to $UPt_3$ using relativistic wavefunctions from a local density b