December 1993 arXiv papers — page 8

Mikhail S. Volkov

It is argued that the sphaleron solutions appearing in the Einstein-Yang-Mills theory are important in the transition processes at extremely high energies. Namely, when the energy exceeds the sphaleron mass, the existence of these solutions ensures constructive interference on the set of the overbarrier transition histories interpolating between distinct top

B. Bruegmann

The loop representation plays an important role in canonical quantum gravity because loop variables allow a natural treatment of the constraints. In these lectures we give an elementary introduction to (i) the relevant history of loops in knot theory and gauge theory, (ii) the loop representation of Maxwell theory, and (iii) the loop representation of canoni

Jan Ambjorn, Kazuo Ghoroku

We consider two-dimensional quantum gravity coupled to matter fields which are renormalizable, but not conformal invariant. Questions concerning the $\b$ function and the effective action are addressed, and the effective action and the dressed renormalization group equations are determined for various matter potentials.

J. F. Gunion

We demonstrate that detection of a charged Higgs boson decaying via $\hpm\rta t b$ will be possible at the LHC in $gg\rta \hm t \anti b+\hp b\anti t$ events, provided the $\hp\rta t\anti b$ coupling is substantial, $\mt\gsim 110\gev$, and reasonably efficient and pure $b$-tagging can be performed.

Sadhan K. Adhikari, Lauro Tomio

We calculate the contribution of relativistic dynamics on the neutron-deuteron scattering length and triton binding energy employing five sets trinucleon potential models and four types of three-dimensional relativistic three-body equations suggested in the preceding paper. The relativistic correction to binding energy may vary a lot and even change sign dep

G. E. Brown, R. Machleidt

In his recent publication of a NN phase shift analysis below 160 MeV, Henneck reports relatively large values for the mixing parameter $ε_1$. Based on these results, Henneck suggests that the strength of the $ρ$-meson tensor coupling to the nucleon may be weaker than used in present day NN interactions, like the Paris or Bonn potentials. We point out that at

Dmitri V. Alekseevsky, Janusz Grabowski, Giuseppe Marmo, Peter W. Michor

On a cotangent bundle $T\sp*G$ of a Lie group $G$ one can describe the standard Liouville form $θ$ and the symplectic form $d θ$ in terms of the right Maurer Cartan form and the left moment mapping (of the right action of $G$ on itself), and also in terms of the left Maurer-Cartan form and the right moment mapping, and also the Poisson structure can be writt

Aleksandar KOCIC, John KOGUT

We argue that theories with fundamental fermions which undergo chiral symmetry breaking have several universal features which are qualitatively different than those of theories with fundamental scalars. Several bounds on the critical indices $δ$ and $η$ follow. We observe that in four dimensions the logarithmic scaling violations enter into the Equation of S

Matthias Burkardt

A new method to perform numerical simulations of light-front Hamiltonians formulated on transverse lattices is introduced. The method is based on a DLCQ formulation for the (continuous) longitudinal directions. The hopping term in the transverse direction introduces couplings between fields defined on neighboring $1+1$-dimensional sheets. Within each sheet,

A. Yu. Alekseev, A. Z. Malkin

We consider canonical symplectic structure on the moduli space of flat ${\g}$-connections on a Riemann surface of genus $g$ with $n$ marked points. For ${\g}$ being a semisimple Lie algebra we obtain an explicit efficient formula for this symplectic form and prove that it may be represented as a sum of $n$ copies of Kirillov symplectic form on the orbit of d

D. Amati S. Elitzur, E. Rabinovici

We study 2-d $ϕF$ gauge theories with the objective to understand, also at the quantum level, the emergence of induced gravity. The wave functionals - representing the eigenstates of a vanishing flat potential - are obtained in the $ϕ$ representation. The composition of the space they describe is then analyzed: the state corresponding to the singlet represen

Hiroo Azuma, Satoshi Iso

Explicit relation between Laughlin state of the quantum Hall effect and one-dimensional(1D) model with long-ranged interaction ($1/r^2$) is discussed. By rewriting lowest Landau level wave functions in terms of 1D representation, Laughlin state can be written as a deformation of the ground state of Calogero-Sutherland model. Corresponding to Laughlin state o

N. Bralic

We derive a generalized Stokes' theorem, valid in any dimension and for arbitrary loops, even if self intersecting or knotted. The generalized theorem does not involve an auxiliary surface, but inherits a higher rank gauge symmetry from the invariance under deformations of the surface used in the conventional formulation.

A. D. Dolgov

A review of the present state of the baryogenesis is given with an emphasis on electroweak baryogenesis. Technical details of the numerous models cosidered in the literature are not elaborated but unresolved problems of the issue are considered. Different logically possible alternatives of the electroweak scenarios are presented. A possible impact of barioge

J. Lopez, D. Nanopoulos, G. Park, X. Wang

We present the first constraints on the parameter space of $SU(5)\times U(1)$ supergravity (in both no-scale and dilaton scenarios) which arise from the recently announced limits on trilepton searches at the Tevatron. The trilepton rate has been calculated for those points in parameter space which satisfy not only the minimal theoretical and experimental LEP

Suraj N. Gupta, James M. Johnson, Wayne W. Repko, Casimir J. Suchyta

A theoretical explanation of the observed splittings among the P~states of charmonium is given with the use of a nonsingular potential model for heavy quarkonia. We also show that the recently observed mass difference between the center of gravity of the ${}^3P_J$ states and the ${}^1P_1$ state of $c\bar{c}$ does not provide a direct test of the color hyperf

T. Altherr, P. Salati

By using both thermal field theory and a somewhat more intuitive method, we define the electric charge as well as the charge radius of neutrinos propagating inside a plasma. We show that electron neutrinos acquire a charge radius of order $\sim 6.5 \times 10^{-16}$ cm, regardless of the properties of the medium. Then, we compute the rate of plasmon decay whi

Véronique Bernard, Ulf-G. Meißner, A. A. Osipov

The momentum-space bosonization method is extended to the case of a Nambu--Jona-Lasinio type model with vector and axial-vector mesons. The method presented gives the possibility of deriving any meson vertex function to all orders in momenta and to the leading order in $1/N_c$. Two-point functions, which describe one-particle transitions to the hadronic vacu

M. Bilenky, J. -L. Kneur, F. M. Renard, D. Schildknecht

We study the accuracy to be obtained in measuring trilinear $Z^0W^+W^-$ and $γW^+W^-$ couplings in the reaction $e^+e^- \to W^+W^-$ at "New Linear Collider" energies of $500GeV$ to $1000GeV$. We derive simple scaling laws for the sensitivity in the measurement of these couplings. For most couplings the sensitivity increases as $\sqrt{L\cdot s}$, wher

Aleksandar Kocic

I give a review and progress report on studies of lattice QED. I emphasize analytical results and methods that are applied in data analysis. Also, I derive some bounds for the critical exponents and establish their connection with scaling violations. Triviality, as realized in $ϕ^4$ theory, is ruled out on theoretical grounds. I show that the present data, i

A. Bode, Th. Lippert, K. Schilling

We investigate monopoles in four-dimensional compact U(1) with Wilson action. We focus our attention on monopole clusters as they can be identified unambiguously contrary to monopole loops. We locate the clusters and determine their properties near the U(1) phase transition. The Coulomb phase is characterized by several small clusters, whereas in the confine

C. B. Lang

This is a series of lectures on Monte Carlo results on the non-perturbative, lattice formulation approach to quantum field theory. Emphasis is put on 4D scalar quantum field theory. I discuss real space renormalization group, fixed point properties and logarithmic corrections, partition function zeroes, the triviality bound on the Higgs mass, finite size eff

H. Gausterer

There are problems in physics and particularly in field theory which are defined by complex valued weight functions $e^{-S}$ where $S$ is a polynomial action $S: R^n \rightarrow C $. The conditions under which a convergent complex Langevin calculation correctly simulates such integrals are discussed. All conditions on the process which are used to prove prop

A. R. Levi

Lattice Monte Carlo simulations are performed for the SU(2) Yang Mills gauge theory in the presence of an Abelian background with external sources to obtain information on the effective potential. The goal is to investigate the lowest Landau mode that, in the continuum one-loop effective potential, is the crucial mode for instability. It is shown that also i

Nicholas Hazel

We present an extraction of Vcb from a lattice calculation of the B->D* decay matrix elements. We obtain |Vcb| \sqrt{ \frac{ \tauB }{ 1.49 ps } } = 0.037^{+3 \ +5}_{-3 \ -5} from a single parameter fit to the new CLEO data. Email nmh@uk.ac.ed.ph.th

T D Kieu, C J Griffin

To tackle the sign problem in the simulations of systems having indefinite or complex-valued measures, we propose a new approach which yields statistical errors smaller than the crude Monte Carlo using absolute values of the original measures. The 1D complex-coupling Ising model is employed as an illustration.

T D Kieu, C J Griffin

A method is presented to tackle the sign problem in the simulations of systems having indefinite or complex-valued measures. In general, this new approach is shown to yield statistical errors smaller than the crude Monte Carlo using absolute values of the original measures. Exactly solvable, one-dimensional Ising models with complex temperature and complex a

T D Kieu, C J Griffin

Towards a solution to the sign problem in the simulations of systems having indefinite or complex-valued measures, we propose a new approach which yields statistical errors smaller than the crude Monte Carlo using absolute values of the original measures. The 1D complex-coupling Ising model is employed as an illustration.

C. Bernard, M. Golterman

We summarize results for partially quenched chiral perturbation theory and indicate an application to staggered fermion QCD in which the square root of the determinant is taken to reduce the number of flavors from four to two.

M. Buchheit, F. M. Donini, A. Schaerf

Terminological knowledge representation systems (TKRSs) are tools for designing and using knowledge bases that make use of terminological languages (or concept languages). We analyze from a theoretical point of view a TKRS whose capabilities go beyond the ones of presently available TKRSs. The new features studied, often required in practical applications, c

Jian Ma, P. Alméras, R. J. Kelley, H. Berger

A comparative study has been made of iodine-intercalated Bi$_{2}$Sr$_{2}$Ca$_{1}$Cu$_{2}$O$_{x}$ single crystal and 1 atm O$_{2}$ annealed Bi$_{2}$Sr$_{2}$Ca$_{1}$Cu$_{1}$O$_{x}$ single crystal using AC susceptibility measurement, X-ray photoemission (XPS) and angle-resolved ultraviolet photoemission spectroscopy (ARUPS). AC susceptibility measurement indica

Fernando Sols, Jaime Ferrer

The crossover between ideal Josephson behavior and uniform superconducting flow is studied by solving exactly the Ginzburg-Landau equation for a one-dimensional superconductor in the presence of an effective delta function potential of arbitrary strength. As the effective scattering is turned off, the pairs of Josephson solutions with equal current evolve in

Fong Liu, H. Metiu

The kinetics of monoatomic steps in diffusion-controlled crystal growth and evaporation processes are investigated analytically using a Green's function approach. Integro-differential equations of motion for the steps are derived; and a systematic linear stability analysis is carried out treating simultaneously perturbations both along and perpendicular

K. J. Runge, G. T. Zimanyi

We investigate the one-dimensional quantum $XXZ$ model in the presence of diagonal disorder. Recently the model has been analyzed with the help of field-theoretical renormalization group methods, and a phase diagram has been predicted. We study the model with exact diagonalization techniques up to chain lengths of 16 sites. Using finite-size scaling methods

Jaedong Noh, Doochul Kim

We investigate the thermodynamic and critical properties of an interacting domain wall model which is derived from the triangular lattice antiferromagnetic Ising model with the anisotropic nearest and next nearest neighbor interactions. The model is equivalent to the general five--vertex model. Diagonalizing the transfer matrix exactly by the Bethe Ansatz me

Richard Nolthenius, Anatoly Klypin, Joel R. Primack

This letter presents results of new high resolution $Ω=1$ Cold + Hot Dark Matter (CHDM) and Cold Dark Matter (CDM) simulations. Properties of groups in these simulations reflect the lower small-scale velocities and the greater tendency to form distinct filaments on both small and large scales in CHDM as compared to CDM. The fraction of galaxies in groups and

P. -M. Binder

Cellular automata (CA) dynamics are ordered in terms of two global parameters, computable {\sl a priori} from the description of rules. While one of them (activity) has been used before, the second one is new; it estimates the average sensitivity of rules to small configurational changes. For two well-known families of rules, the Wolfram complexity Classes c