June 1993 arXiv papers — page 2

R. D'Auria, S. Ferrara, M. Villasante

We consider the compactification of the dual form of $N=1$ $D=10$ supergravity on a six-dimensional Calabi-Yau manifold. An $N=1$ off-shell supergravity effective Lagrangian in four dimensions can be constructed in a dual version of the gravitational sector (new-minimal supergravity form). Superspace duality has a simple interpretation in terms of Poincaré d

T. G. Rizzo

A recent analysis has shown that it may be possible at the SSC to extract information about $Z'$ couplings via the decay $Z' \to jj$. This technique was found to be useful for some extended electroweak models provided the $Z'$ is relatively light. In the present paper, we generalize this procedure to the LHC and to $Z'$'s which are more m

Pierre Ramond

We present partial numerical results in the Minimal Supersymmetric Standard Model with soft breaking of supersymmetry, and radiative breaking of the electroweak symmetry. We impose the additional relation, bottom mass = tau mass at the GUT scale. For the special case of the strict no-scale model, in which global supersymmetry breaking arises solely from soft

Adam F. Falk, Benjamin Grinstein

The combined use of chiral $SU(3)$ and heavy quark symmetries allows one to relate the hadronic form factors for the decay $\bar B\to \bar K\e^+\e^-$ to those for $\bar B\toπ\e^-\barν$. We investigate departures from the symmetry limit which arise from chiral symmetry breaking. The analysis uses chiral perturbation theory and the heavy quark limit to compute

Christian Holm, Wolfhard Janke

We use single-cluster Monte Carlo simulations to study the role of topological defects in the three-dimensional classical Heisenberg model on simple cubic lattices of size up to $80^3$. By applying reweighting techniques to time series generated in the vicinity of the approximate infinite volume transition point $K_c$, we obtain clear evidence that the tempe

C. G. Torre

Using a recent classification of local symmetries of the vacuum Einstein equations, it is shown that there can be no observables for the vacuum gravitational field (in a closed universe) built as spatial integrals of local functions of Cauchy data and their derivatives.

Claus Kiefer, Erik A. Martinez

Any quantum theory of gravity which treats the gravitational constant as a dynamical variable has to address the issue of superpositions of states corresponding to different eigenvalues. We show how the unobservability of such superpositions can be explained through the interaction with other gravitational degrees of freedom (decoherence). The formal framewo

D. P. Datta

Three different methods viz. i) a perturbative analysis of the Schrödinger equation ii) abstract differential geometric method and iii) a semiclassical reduction of the Wheeler-Dewitt equation, relating Pancharatnam phase to vacuum instability are discussed. An improved semiclassical reduction is also shown to yield the correct zeroth order semicalssical Ein

Hyeong-Chai Jeong, Paul J. Steinhardt

We present evidence for a novel finite-temperature phase transition in the phason elasticity of quasicrystals. A tiling model for energetically stabilized decagonal quasicrystals has been studied in an extensive series of Monte Carlo simulation. Hamiltonian (energetics) of the model is given by nearest-neighbor Penrose-like matching rules between three dimen

Jysoo Lee

We study density waves in the flows of granular particles through vertical tubes and hoppers using both analytic methods and molecular dynamics (MD) simulations. We construct equations of motion for quasi one-dimensional systems. The equations, combined with the Bagnold's law for friction, are used to describe the time evolutions of the density and the v

Steven A. Janowsky, Joel L. Lebowitz

We present new results for the current as a function of transmission rate in the one dimensional totally asymmetric simple exclusion process (TASEP) with a blockage that lowers the jump rate at one site from one to r < 1. Exact finite volume results serve to bound the allowed values for the current in the infinite system. This proves the existence of a gap i

Troy Shinbrot, J. M. Ottino

In this letter, we show that coherent structures are related to folds of horseshoes which are present in chaotic systems. We develop techniques that allow us to construct coherent structures by manipulating folds in three prototypical problems: a 1-D chaotic map, a 2-D chaotic map, and a chaotically advected fluid. The ability to construct such structures is

Sun, C. P, L. H. Yu

The quantum dynamics of a simplest dissipative system, a particle moving in a constant external field , is exactly studied by taking into account its interaction with a bath of Ohmic spectral density. We apply the main idea and methods developed in our recent work [1] to quantum dissipative system with constant external field. Quantizing the dissipative syst

A. A. Bytsenko, E. Elizalde, S. D. Odintsov, S. Zerbini

The Mellin-Barnes representation for the free energy of the genus-$g$ string is constructed. It is shown that the interactions of the open bosonic string do not modify the critical (Hagedorn) temperature. However,for the sectors having a spinor structure, the critical temperature exists also for all $g$ and depends on the windings. The appearance of a period

Max Tegmark, Joseph Silk, August Evrard

A model is presented in which supernova-driven winds from early galaxies reionize the intergalactic medium by z=5. This scenario can explain the observed absence of a Gunn-Peterson trough in the spectra of high-redshift quasars providing that the bulk of these early galaxies are quite small, no more massive than about 10^8 solar masses. It also predicts that

Robert I. McLachlan, Harvey Segur

We study the motion of surfaces in an intrinsic formulation in which the surface is described by its metric and curvature tensors. The evolution equations for the six quantities contained in these tensors are reduced in number in two cases: (i) for arbitrary surfaces, we use principal coordinates to obtain two equations for the two principal curvatures, high

K. Suzuki, R. Okamoto, P. J. Ellis, T. T. S. Kuo

We generalize the Lee-Suzuki iteration method for summing the folded diagram series to the case where the unperturbed model-space energies are non-degenerate. A condition is derived for the convergence of the iteration scheme and this depends on the choice of the model space projection operators. Two choices are examined, in the first the projection operator

Edward Witten

Not only in physical string theories, but also in some highly simplified situations, background independence has been difficult to understand. It is argued that the ``holomorphic anomaly&#39;&#39; of Bershadsky, Cecotti, Ooguri, and Vafa gives a fundamental explanation of some of the problems. Moreover, their anomaly equation can be interpreted in terms of a

M. Khorrami

We consider one dimensional lattice gauge theories constructed by the minimal coupling prescription. It is shown that these theories are exactly solvable in the thermodynamic limit. After considering the most general case, we discuss some special cases on finite lattices, and also work out some examples. There is no phase transition in these minimally couple

Stephen P. Martin, Pierre Ramond

The supersymmetric standard model with supergravity-inspired soft breaking terms predicts a rich pectrum of sparticles to be discovered at the SSC, LHC and NLC. Because there are more supersymmetric particles than unknown parameters, one can write down sum rules relating their masses. We discuss the pectrum of sparticles from this point of view. Some of the

kingman Cheung

We will summarize some aspects of the standard model Higgs boson at high energy $γγ$ colliders, where the photon beams are realized by the laser backscattering method, including the direct Higgs boson production via $γγ\rightarrow H$, and the measurement of the Yukawa coupling via the channel $γγ\rightarrow t\bar tH$.

J. Baacke, S. Junker

We have performed a new exact evaluation of the fluctuation determinant $κ$ of the electroweak sphaleron with $Θ_W =0$. The results differ significantly from a previous calculation of this quantity by Carson et. al. . We find that $κ$ is of order 1 in units $(gv)^6$ while the previous results indicated a strong suppression of the sphaleron transition by this

O. J. P. Eboli, M. C. Gonzalez-Garcia, S. F. Novaes

We study the production of gauge boson pairs at the next generation of linear $e^+e^-$ colliders operating in the $eγ$ mode. The processes $eγ\rightarrow VV^\prime F$ ($V,V^\prime =W$, $Z$, or $γ$ and $F=e$ or $ν$) can give valuable information on possible deviations of the quartic vector boson couplings from the Standard Model predictions. We establish the

J. Schlienz, H. Weigel, H. Reinhardt, R. Alkofer

A regularization for the baryon number consistent with the energy in the Nambu-Jona-Lasinio model is introduced. The soliton solution is constructed with the regularized baryon number constrained to unity. It is furthermore demonstrated that this constraint prevents the soliton from collapsing when scalar fields are allowed to be space dependent. In this sch

B. E. Hanlon, G. C. Joshi

We consider the construction of $SU(2)_{L}\otimes SU(2)_{R}\otimes SU(4)$ partial unification models as an example of phenomenologically acceptable unification models in the absence of supersymmetry in non-commutative geometry. We exploit the Chamseddine, Felder and Fröhlich generalization of the Connes and Lott model building prescription. By introducing a

Paolo Provero

We consider the valley--method computation of the inclusive cross section of baryon number violating processes in the Standard Model. We show that any physically correct model of the valley action should present a singularity in the saddle point valley parameters as functions of the energy of the process. This singularity prevents the saddle point configurat

F. Karsch, M. L. Laursen, T. Neuhaus, B. Plache

We study the temperature dependence of the Chern-Simons number fluctuations in the SU(2) Higgs Model on Euclidean lattices with spatial sizes up to 20^3. Temperatures well above the Higgs phase transition $T_H$ are achieved on anisotropic lattices. Numerical results are compared to perturbative results on finite lattices as well as in continuum perturbation

J. Rauch, A. D. Rendall

The behaviour of test fields near a compact Cauchy horizon is investigated. It is shown that solutions of nonlinear wave equations on Taub spacetime with generic initial data cannot be continued smoothly to both extensions of the spacetime through the Cauchy horizon. This is proved using an energy method. Similar results are obtained for the spacetimes of Mo

M. R. Norman

In a recent Letter, Gloos et al have suggested that the heavy fermion superconductor, UPd_2Al_3, has a transition in magnetic field from the normal state to an inhomogeneous superconducting state, known as the LOFF state, followed at lower fields by a first order phase transition to the usual flux lattice state. To investigate this, the author derives a form

W. Pfaff, D. Weinmann, W. Haeusler, B. Kramer

The influence of excited levels on nonlinear transport properties of a quantum dot weakly coupled to leads is studied using a master--equation approach. A charging model for the dot is compared with a quantum mechanical model for interacting electrons. The current--voltage curve shows Coulomb blockade and additional finestructure that is related to the excit

Tomo Munehisa, Yasuko Munehisa

We propose new approach to numerical study of quantum spin systems. Our method is based on a fact that one can use any set of states for the path integral as long as it is complete. We apply our method to one-dimensional quantum spin system with next-to-nearest neighbor interactions. We found remarkable improvement in negative sign problem.

P. Fischer, D. L. Welch, M. Mateo, P. Côté

In this paper we have examined the internal dynamics of the globular cluster NGC 362. A V band surface brightness profile (SBP) was constructed from CCD images, and, after it was determined that the cluster is not post core-collapse, fit with single- and multi-mass King-Michie (KM) models. The total cluster luminosity is 1.70 $\pm 0.1 \times 10^5$ L$_V$\sol.

Martina Niemeyer, Peter L. Biermann

We model farinfrared (FIR) spectra of radioweak quasars with the assumption that the emission is from heated dust, and that the heating is due to the central engine via energetic particles. These energetic particles are diffusing from a postulated source near the central engine through a tenuous galactic halo to arrive at the dust which is taken to be in mol

Enrique Arrondo, Marina Bertolini, Cristina Turrini

We give a classification and a construction of all smooth $(n-1)$-dimensional varieties of lines in ${\bf P}\sp n$ verifying that all their lines meet a curve. This also gives a complete classification of $(n-1)$-scrolls over a curve contained in $G(1,n)$.

Hidenori Sonoda

By studying the geometric properties of correlation functions on the theory space, we are naturally led to a connection for the infinite dimensional vector bundle of composite fields over the theory space. We show how the short distance singularities of the theory are determined by the geometry of the theory space, i.e., the connection, beta functions, and a

J. M. Byers, M. E. Flatte&#39;, D. J. Scalapino

Changes: figures added in postscript form, Eq. (7) and various typos corrected. We examine the effect of an impurity on the nearby tunneling conductance in an anisotropically-gapped superconductor. The variation of the conductance has pronounced spatial dependence which depends strongly on the Fermi surface location of gap extrema. In particular, different g

Thomas Peternell, Jaroslaw A. Wisniewski

In the present paper we discuss stability of the tanget bundle of a Fano n-fold of index >= n-2 and b_2=1. For example, we prove that all Fano 4-folds with b_2=1 have stable tangent bundle. For this purpose we prove some vanishing theorems for sheaves of twisted holomorphic forms on ample divisors and cyclic coverings of manifolds having &#34;special cohomol

J. Sladkowski

It is shown that the Stückelberg formalism can be regarded as a field-enlarging transformation that introduces an additional gauge symmetry to the considered model. The appropriate BRST charge can be defined. The physical state condition, demanding that that a physical state is to be anihilated by the BRST charge, is shown to be equivalent to the Stückelberg

Jean Avan

We describe the $R$-matrix structure associated with integrable extensions, containing both one-body and two-body potentials, of the $A_N$ Calogero-Moser $N$-body systems. We construct non-linear, finite dimensional Poisson algebras of observables. Their $N \rightarrow \infty$ limit realize the infinite Lie algebras Sdiff$({\Bbb R} \times S_1 )$ in the trigo

Armen Nersessian

Using odd symplectic structure constructed over tangent bundle of the symplectic manifold, we construct the simple supergeneralization of an arbitrary Hamiltonian mechanics on it. In the case, if the initial mechanics defines Killing vector of some Riemannian metric, corresponding supersymmetric mechanics can be reformulated in the terms of even symplectic s

U. Kalmbach, T. Vetter, T. S. Biro, U. Mosel

On the basis of the Friedberg-Lee model we formulate a semiclassical transport theory to describe the phase-space evolution of nucleon-nucleon collisions on the quark level. The time evolution is given by a Vlasov-equation for the quark phase-space distribution and a Klein-Gordon equation for the mean-field describing the nucleon as a soliton bag. The Vlasov

Manuel Barriola, Tanmay Vachaspati, Martin Bucher

We give a prescription for embedding classical solutions and, in particular, topological defects in field theories which are invariant under symmetry groups that are not necessarily simple. After providing examples of embedded defects in field theories based on simple groups, we consider the electroweak model and show that it contains the $Z$ string and a on

Peter Vecsernyés

We introduce the notion of rational Hopf algebras that we think are able to describe the superselection symmetries of two dimensional rational quantum field theories. As an example we show that a six dimensional rational Hopf algebra $H$ can reproduce the fusion rules, the conformal weights, the quantum dimensions and the representation of the modular group

D. Z. Freedman, G. Lozano, N. Rius

Differential regularization is applied to a field theory of a non-relativistic charged boson field $ϕ$ with $λ(ϕ{}^{*} ϕ)^2$ self-interaction and coupling to a statistics-changing $U(1)$ Chern-Simons gauge field. Renormalized configuration-space amplitudes for all diagrams contributing to the $ϕ{}^{*} ϕ{}^{*} ϕϕ$ 4-point function, which is the only primitive

F. C. Alcaraz, V. Rittenberg

We show that the master equation governing the dynamics of simple diffusion and certain chemical reaction processes in one dimension give time evolution operators (Hamiltonians) which are realizations of Hecke algebras. In the case of simple diffusion one obtains, after similarity transformations, reducible hermitian representations while in the other cases

Jan Sladkowski

It is argued that the noncommutative geometry construction of the standard model predicts a nonlinear symmetry breaking mechanism rather than the orthodox Higgs mechanism. Such models have experimentally verifiable consequences.

Jan Sladkowski

A field-enlarging transformation in the chiral electrodynamics is performed. This introduces an additional gauge symmetry to the model that is unitary and anomaly-free and allows for comparison of different models discussed in the literature. The problem of superfluous degrees of freedom and their influence on quantization is discussed. Several &#34;mysterie

M. A. Doncheski, F. Halzen, C. S. Kim, M. L. Stong

The difference in production rate between $W^+$ and $W^-$ at hadron colliders is very sensitive to the the difference between up- and down-quark distributions in the proton. This sensitivity allows for a variety of useful measurements. We consider the difference $d_s(x,Q^2) - u_s(x,Q^2)$ in the sea distributions and the difference $Δu(x,Q^2) - Δd(x,Q^2)$ in

Jean-Paul Blaizot, Dmitri Diakonov

In high energy heavy ion collisions the pion multiplicity is large, and one might expect that pions are radiated semi-classically. The axial symmetry of the collision and approximately zero isotopic spin of the colliding nuclei result then in peculiar isotopic spin -- azimuth correlations of the produced pions. These correlations are easy to test -- and shou

C. A. Savoy

The connection between the scales of $ {\rm SU} (2)\times {\rm U} (1) $ gauge symmetry breaking and supersymmetry breaking is didactically displayed in the framework of a T.O.Y. (Theory Overestimating Yukawas) model, a version of the $ (M+1)SSM $ (supersymmetric extension of the standard model with a gauge singlet) in which the relevant parameters are determ

H. Suman, K. Schilling

Gauge fixing is a frequent task encountered in practical lattice gauge theory calculations. We review the performance characteristics of some standard gauging procedures for non-abelian gauge theories, implemented on the parallel machines CM2 and CM5.

Alberto Saa

Gauge fields are described on an Riemann-Cartan space-time by means of tensor-valued differential forms and exterior calculus. It is shown that minimal coupling procedure leads to a gauge invariant theory where gauge fields interact with torsion, and that consistency conditions for the gauge fields impose restrictions in the non-Riemannian structure of space

Albert-László Barabási

A number of recent experiments have showed that surfactants can modify the growth mode of an epitaxial film, suppressing islanding and promoting layer-by-layer growth. Here I introduce a set of coupled equations to describe the nonequilibrium roughening of an interface covered with a thin surfactant layer. The surfactant may drive the system into a novel pha

Martin D. Weinberg

A perturber may excite a coherent mode in a star cluster or galaxy. If the stellar system is stable, it is commonly assumed that such a mode will be strongly damped and therefore of little practical consequence other than redistributing momentum and energy deposited by the perturber. This paper demonstrates that this assumption is false; weakly damped modes

Redouane Fakir

When a source of gravity waves is conveniently placed between the Earth and some source of light, preferably a pulsating source, the magnitude of time delays induced by the gravity waves could, in optimal situations, be not too far out of the reach of already existing technology. Besides the odd case of near-to-perfect alignment one might be lucky enough to

I. K. Kostov

The U(N) gauge theory on a D-dimensional lattice is reformulated as a theory of lattice strings (a statistical model of random surfaces). The Boltzmann weights of the surfaces can have both signs and are tuned so that the longitudinal modes of the string are elliminated. The U(\infty) gauge theory is described by noninteracting planar surfaces and the 1/N co

M. R. Norman

The simple argument given in the previous version &#34;that almost certainly restricts heavy fermion UPd_2Al_3 to be an odd parity superconductor with a single component order parameter&#34; is not correct.

Hermann Schulz

The longitudinal-electric oscillations of the hot gluon system are studied beyond the well known leading order term at high temperature $T$ and small coupling $g$. The coefficient $η$ in $ω^2 = m^2 \, (1+ η\, g \wu N \, )$ is calculated, where \hbox{$ω\equiv ω(\vc q =0)$} is the long-wavelength limit of the frequency spectrum, $N$ the number of colours and $

Edward Witten

Simple mean field methods can be used to describe transitions between different space-time models in string theory. These include transitions between different Calabi-Yau manifolds, and more exotic things such as the Calabi-Yau/Landau-Ginzberg correspondence.

C. P. Korthals-Altes, S. Nicolis, J. Prades

Chiral defect fermions on the lattice in 4+1 dimensions are analyzed using mean field theory. The fermion propagator has a localized chiral mode in weak coupling but loses it when the coupling in the unphysical fifth direction becomes too large. A layered phase à la Fu-Nielsen appears where the theory is vector-like in every layer.

E. Lopez

In this paper we study the quantum Clifford-Hopf algebras $\widehat{CH_q(D)}$ for even dimensions $D$ and obtain their intertwiner $R-$matrices, which are elliptic solutions to the Yang- Baxter equation. In the trigonometric limit of these new algebras we find the possibility to connect with extended supersymmetry. We also analyze the corresponding spin chai

Jean-Paul BLAIZOT, Edmond IANCU

THE PREVIOUS LATEX STRUCTURE WAS MODIFIED IN ORDER TO ALLOW FOR A DIRECT IMPRESSION OF THE PAPER, WITHOUT SUPPLEMENTARY SPLITTING. THERE IS NO TEXT MODIFICATION.

Toshiya Kawai, Yasuhiko Yamada, Sung-Kil Yang

Recently Witten proposed to consider elliptic genus in $N=2$ superconformal field theory to understand the relation between $N=2$ minimal models and Landau-Ginzburg theories. In this paper we first discuss the basic properties satisfied by elliptic genera in $N=2$ theories. These properties are confirmed by some fundamental class of examples. Then we introdu

Stefan Teis, Wolfgang Cassing, Tomoyuki Maruyama, Ulrich Mosel

The production of antiprotons in proton-nucleus and nucleus-nucleus reactions is calculated within the relativistic BUU approach employing proper selfenergies for the baryons and antiprotons and treating the p-bar annihilation nonperturbatively. The differential cross section for the antiprotons is found to be very sensitive to the p-bar selfenergy adopted.

Bernard Maurey

In this note we show that every Banach space $X$ not containing $\ell_1^n$ uniformly and with unconditional basis contains an arbitrarily distortable subspace.

R. Komowski, Nicole Tomczak-Jaegermann

For a large class of Banach spaces, a general construction of subspaces without local unconditional structure is presented. As an application it is shown that every Banach space of finite cotype contains either $l_2$ or a subspace without unconditional basis, which admits a Schauder basis. Some other interesting applications and corollaries follow.

Denny H. Leung

A Banach space is $c_0$-saturated if all of its closed infinite dimensional subspaces contain an isomorph of $c_0$. In this article, we study the stability of this property under the formation of direct sums and tensor products. Some of the results are: (1) a slightly more general version of the fact that $c_0$-sums of $c_0$-saturated spaces are $c_0$-satura

Nathan Berkovits

By replacing two of the bosonic scalar superfields of the N=2 string with fermionic scalar superfields (which shifts $d_{critical}$ from (2,2) to (9,1)), a quadratic action for the ten-dimensional Green-Schwarz superstring is obtained. Using the usual N=2 super-Virasoro ghosts, one can construct a BRST operator, picture-changing operators, and covariant vert

J. A. Gracey

We solve the conformal bootstrap equations of the four fermi model or $O(N)$ Gross Neveu model to deduce the fermion anomalous dimension of the theory at $O(1/N^3)$ in arbitrary dimensions.

J. A. Gracey

By using the corrections to the asymptotic scaling forms of the fields of the $O(N)$ Gross Neveu model to solve the dressed skeleton Schwinger Dyson equations, we deduce the critical exponent corresponding to the $β$-function of the model at $O(1/N^2)$.

J. A. Gracey

We solve the gauged Nambu--Jona-Lasinio model at leading order in the large $N$ expansion by computing the anomalous dimensions of all the fields of the model and other gauge independent critical exponents by examining the scaling behaviour of the Schwinger Dyson equation. We then restrict to the three dimensional model and include a Chern Simons term to dis

C. Ahn, G. Delfino, G. Mussardo

The $S$-matrix of the Ising Model can be obtained as particular limit of the roaming trajectories associated to of the $S$-matrix of the Sinh-Gordon model. Using the form factors of the Sinh-Gordon, we analyse the correspondence between the operators of the two theories.

J. Avan, O. Babelon, M. Talon

We use the definition of the Calogero-Moser models as Hamiltonian reductions of geodesic motions on a group manifold to construct their $R$-matrices. In the Toda case, the analogous construction yields constant $R$-matrices. By contrast, for Calogero-Moser models they are dynamical objects.

M. Henneaux

A simplified proof of a theorem by Joglekar and Lee on the renormalization of local gauge invariant operators in Yang-Mills theory is given. It is based on (i) general properties of the antifield-antibracket formalism; and (ii) well-established results on the cohomology of semi-simple Lie algebras.

M. Henneaux

When one uses the Dirac bracket, second class constraints become first class. Hence, they are amenable to the BRST treatment characteristic of ordinary first class constraints. This observation is the starting point of a recent investigation by Batalin and Tyutin, in which all the constraints are put on the same footing. However, because second class constra

Shogo Tanimura

We consider the uncertainty relation between position and momentum of a particle on $ S^1 $ (a circle). Since $ S^1 $ is compact, the uncertainty of position must be bounded. Consideration on the uncertainty of position demands delicate treatment. Recently Ohnuki and Kitakado have formulated quantum mechanics on $ S^D $ (a $D$-dimensional sphere). Armed with

Shin&#39;ich Nojiri, Ichiro Oda

We analyze quantum two dimensional dilaton gravity model, which is described by $SL(2,R)/U(1)$ gauged Wess-Zumino-Witten model deformed by $(1,1)$ operator. We show that the curvature singularity does not appear when the central charge $c_{\rm matter}$ of the matter fields is given by $22<c_{\rm matter}<24$. When $22<c_{\rm matter}<24$, the matter shock wave

Keh-Fei Liu, Shao-Jing Dong

Using the Euclidean path-integral formulation for the hadronic tensor, we show that the violation of the Gottfried sum rule does not come from the disconnected quark-loop insertion. Rather, it comes from the connected (quark line) insertion involving quarks propagating in the backward time direction. We demonstrate this by studying sum rules in terms of the

L. Lavoura

Analysis of the model of Babu and Mohapatra for the mass matrices in SO(10), with survey of the different types of neutrino spectra possible in that model

M. Shaposhnikov

It is argued that confining effects in 3-dimensional non-Abelian gauge theories (high-temperature limit of 4-dimensional ones) imply the existence of the condensates of the gauge and Higgs fields in 3-d vacuum. This non-perturbative effect can decrease the energy of the phase with unbroken symmetry and may result in the creation of a barrier separating the b

F. R. Klinkhamer

We present a self-consistent ansatz for a new sphaleron in the electroweak standard model. The resulting field equations are solved numerically. This sphaleron sets the height of the energy barrier for the global SU(2) anomaly.

David H. Lyth

Saxino decay can generate significant cosmological entropy, and hence dilute theoretical estimates of the present mass density of a given particle species. The dilution factor depends on the saxino and axion masses, and is constrained by the requirement that saxino decay should not affect nucleosynthesis, as well as by the usual requirement that the axion de

Philip D. Mannheim

We discuss some outstanding open questions regarding the validity and uniqueness of the standard second order Newton-Einstein classical gravitational theory. On the observational side we discuss the degree to which the realm of validity of Newton's Law of Gravity can actually be extended to distances much larger than the solar system distance scales on which

A. J. van der Sijs

The Heisenberg model, a quantum mechanical analogue of the Ising model, has a large ground state degeneracy, due to the symmetry generated by the total spin. This symmetry is also responsible for degeneracies in the rest of the spectrum. We discuss the global structure of the spectrum of Heisenberg models with arbitrary couplings, using group theoretical met

R. Deutscher, H. U. Everts

We study the ground state properties of the S=$\frac{1}{2}$ Heisenberg antiferromagnet (HAF) on the triangular lattice with nearest-neighbour ($J$) and next-nearest neighbour ($αJ$) couplings. Classically, this system is known to be ordered in a $120^\circ$ Néel type state for values $-\infty<α\le 1/8$ of the ratio $α$ of these couplings and in a collinear s

J. Bricmont, A. Kupiainen

We use Renormalization Group ideas to study stability of moving fronts in the Ginzburg-Landau equation in one spatial dimension. In particular, we prove stability of the real fronts under complex perturbations. This extends the results of Aronson and Weinberger to situations where the maximum principle is inapplicable and constitutes a step in proving the ge

J. Bricmont, A. Kupiainen, G. Lin

We present a general method for studying long time asymptotics of nonlinear parabolic partial differential equations. The method does not rely on a priori estimates such as the maximum principle. It applies to systems of coupled equations, to boundary conditions at infinity creating a front, and to higher (possibly fractional) differential linear terms. We p

J. Bricmont, A. Kupiainen

We consider the classical problem of the blowing-up of solutions of the nonlinear heat equation. We show that there exist infinitely many profiles around the blow-up point, and for each integer $k$, we construct a set of codimension $2k$ in the space of initial data giving rise to solutions that blow-up according to the given profile.

Renata Kallosh

We consider static black holes, which are bosonic solutions of supersymmetric theories. We will show that supersymmetry provides a natural framework for a discussion of various properties of such static black holes. The most fundamental property of simple global supersymmetry, non-negativeness of the energy, is generalized in the black hole theory to cosmic

Andrzej Czarnecki

We present complete one-loop radiative corrections to the decay rate of a top quark into a charged Higgs boson and a bottom quark, and for the decay of a charged Higgs boson into leptons. The results are discussed in the framework of the two Higgs boson extension of the Standard Model suggested by supersymmetry. The effect of electroweak corrections after ex

Valeri V. Dvoeglazov

The interaction of the spinor field with the Weinberg&#39;s $2(2S+1)$- component massless field is considered. New interpretation of the Weinberg&#39;s spinor is proposed. The equation analogous to the Dirac oscillator is obtained.

Stefan V. Mashkevich

Using the symmetry properties of the three-anyon spectrum, we obtain exactly the multiplicities of states with given energy and angular momentum. The results are shown to be in agreement with the proper quantum mechanical and semiclassical considerations, and the unexplained points are indicated.

Yuval Grossman, Yosef Nir

In models of three or more scalar doublets, new CP violating phases appear in charged scalar exchange. These phases affect CP asymmetries in neutral $B$ decays, even if Natural Flavor Conservation holds. The recent upper bound on the decay $b\rightarrow sγ$ constrains the effect to be at most of order a few percent. Modifications of constraints on the CKM pa

Joshua A. Frieman, Enrique Gaztanaga

We analyze the consequences of models of structure formation for higher-order ($n$-point) galaxy correlation functions in the mildly non-linear regime. Several variations of the standard $Ω=1$ cold dark matter model with scale-invariant primordial perturbations have recently been introduced to obtain more power on large scales, 20 h$^{-1}$ Mpc, e.g., low-mat

Sergey Fomin, Anatol N. Kirillov

Exponential solutions of the Yang-Baxter equation give rise to generalized Schubert polynomials and corresponding symmetric functions. We provide several descriptions of the local stationary algebra defined by this equation. This allows to construct various exponential solutions of the YBE. The $B_n$ and $G_2$ cases are also treated.

Randall D. Kamien, T. C. Lubensky

We propose a model of directed lines where the average direction has the nature of a cholesteric liquid crystal. This model, for instance, would describe the liquid of screw dislocations in the twist-grain-boundary (TGB) phase of liquid crystals. We show that the presence of lines does not alter the long wavelength elasticity of a cholesteric and, therefore,

N. B. Wilding

The field mixing that manifests broken particle-hole symmetry is studied for a 2-D asymmetric lattice gas model having tunable field mixing properties. Monte Carlo simulations within the grand canonical ensemble are used to obtain the critical density distribution for different degrees of particle-hole asymmetry. Except in the special case when this asymmetr

P. A. Skordos

A new approach of implementing initial and boundary conditions for the lattice Boltzmann method is presented. The new approach is based on an extended collision operator that uses the gradients of the fluid velocity. The numerical performance of the lattice Boltzmann method is tested on several problems with exact solutions and is also compared to an explici

Fulvio Melia, Ranjeev Misra

The long-term transitions of the black hole candidate Cygnus X-1 (between the states gamma_1, gamma_2, and gamma_3) include the occasional appearance of a strong ~ MeV bump (gamma_1), whose strength appears to be anti-correlated with the continuum flux (~ 400 keV) due to the Compton upscattering of cold disk photons by the inner, hot corona. We develop a sel

Ravi Kuchimanchi, R. N. Mohapatra

In a class of supersymmetric left-right models (SUSYLR) of weak interactions where R-parity is automatically conserved, we show that spontaneous breakdown of parity CANNOT occur without spontaneous breakdown of R-parity. This intriguing result connects two physically different scales in supersymmetric models.