March 1994 arXiv papers — page 5

I. Antoniadis, K. Benakli, M. Quirós

Perturbative breaking of supersymmetry in four-dimensional string theories predict in general the existence of new large dimensions at the TeV scale. Such large dimensions lie in a domain of energies accessible to particle accelerators. Their main signature is the production of Kaluza-Klein excitations which can be detected at future colliders. We study this

Burkhard Kleihaus, Jutta Kunz

We construct multisphaleron solutions in the weak interactions. The multisphaleron solutions carry Chern-Simons charge $n/2$, where $n$ is an integer. The well-known sphaleron has $n=1$ and is spherically symmetric for vanishing mixing angle. In contrast the multisphalerons with $n>1$ are only axially symmetric, even for vanishing mixing angle. The greater $

Tadashi Kon, Tetsuro Kobayashi, Shoichi Kitamura

In the framework of the minimal supersymmetric standard model with an R-parity breaking coupling of the scalar top quark (stop) we investigate production processes and decay properties of the stop at HERA energies. The model is characterized by a light stop possibly lighter than the other squarks. We show that the stop could be singly produced not only in th

Myron Bander, H. R. Rubinstein

Expected atmospheric ${\bar ν_e}$ fluxes will result in a significant number of resonantly produced low mass hadronic vector states, as the $ρ$, in large volume neutrino telescopes. The existence of sources of higher energy neutrinos will result in the production of higher mass states, as the $D_s^*$ and the $({\bar t}b)_{J=1}$. We calculate the rates of pro

S. Bilke, Z. Burda, J. Jurkiewicz

We describe a method of Monte-Carlo simulations of simplicial quantum gravity coupled to matter fields. We concentrate mainly on the problem of implementing effectively the random, dynamical triangulation and building in a detailed-balance condition into the elementary transformations of the triangulation. We propose a method of auto-tuning the parameters ne

L. Del Debbio, A. Di Giacomo, Yu. Simonov

We measure field-strength and their correlators in presence of a static $q \bar q$ pair by numerical simulations. We give an interpretation of these data in terms of quadratic and quartic cumulants.

Vivek Iyer, Robert M. Wald

We consider a general, classical theory of gravity with arbitrary matter fields in $n$ dimensions, arising from a diffeomorphism invariant Lagrangian, $\bL$. We first show that $\bL$ always can be written in a ``manifestly covariant" form. We then show that the symplectic potential current $(n-1)$-form, $þ$, and the symplectic current $(n-1)$-form, $\om$

X. G. Wu, J. K. Jain

We show that the excitation spectrum of interacting electrons at filling factor $ν=ν^*/(2ν^*+1)$ is well described in terms of non-interacting composite fermions at filling factor $ν^*$, but does not have a one-to-one correspondence with the excitation spectrum of non-interacting electrons at $ν^*$. In particular, the collective modes of the fractional quant

Harold U. Baranger, Pier A. Mello

We deduce the effects of quantum interference on the conductance of chaotic cavities by using a statistical ansatz for the S matrix. Assuming that the circular ensembles describe the S matrix of a chaotic cavity, we find that the conductance fluctuation and weak-localization magnitudes are universal: they are independent of the size and shape of the cavity i

C. W. J. Beenakker, B. Rejaei, J. A. Melsen

The length dependence is computed of the resistance of a disordered normal-metal wire attached to a superconductor. The scaling of the transmission eigenvalue distribution with length is obtained exactly in the metallic limit, by a transformation onto the isobaric flow of a two-dimensional ideal fluid. The resistance has a minimum for lengths near l/Gamma, w

Kazumasa Miyake, Osamu Narikiyo

It is shown that the charge susceptibility in nearly half-filled two-dimensional (2D) metals, with technically nested Fermi surface, shows anomaly at the wavevector different from that for the spin susceptibility at low temperatures. Namely charge degrees of freedom behave there as if their ``Fermi surface" corresponded to that of ``holes" created in

Jun Pan, Mushti V. Ramakrishna

A structural model for intermediate sized silicon clusters is proposed that is able to generate unique structures without any dangling bonds. This structural model consists of bulk-like core of five atoms surrounded by fullerene-like surface. Reconstruction of the ideal fullerene geometry results in the formation of crown atoms surrounded by $π$-bonded dimer

Steven W. Rick, B. J. Berne

The calculation of the solvation properties of a single water molecule in liquid water is carried out in two ways. In the first, the water molecule is placed in a cavity and the solvent is treated as a dielectric continuum. This model is analyzed by numerically solving the Poisson equation using the DelPhi program. The resulting solvation properties depend s

R. C. Nichol, M. P. Ulmer, R. G. Kron, G. D. Wirth

We present the results of a search for X--ray luminous distant clusters of galaxies. We found extended X--ray emission characteristic of a cluster towards two of our candidate clusters of galaxies. They both have a luminosity in the ROSAT bandpass of $\simeq10^{44}{\rm \,erg\,s^{-1}}$ and a redshift of $>0.5$; thus making them two of the most distant X--ray

S. Matarrese, O. Pantano, D. Saez

A Lagrangian relativistic approach to the non--linear dynamics of cosmological perturbations of an irrotational collisionless fluid is considered. Solutions are given at second order in perturbation theory for the relevant fluid and geometric quantities and compared with the corresponding ones in the Newtonian approximation. Specifically, we compute the dens

Mark Srednicki

We show that a bounded, isolated quantum system of many particles in a specific initial state will approach thermal equilibrium if the energy eigenfunctions which are superposed to form that state obey {\it Berry's conjecture}. Berry's conjecture is expected to hold only if the corresponding classical system is chaotic, and essentially states that th

P. Furlan, A. Ch. Ganchev, V. B. Petkova

The BRST quantisation of the Drinfeld - Sokolov reduction applied to the case of $A^{(1)}_2\,$ is explored to construct in an unified and systematic way the general singular vectors in ${\cal W}_3$ and ${\cal W}_3^{(2)}$ Verma modules. The construction relies on the use of proper quantum analogues of the classical DS gauge fixing transformations. Furthermore

A. Berkovich

The Hilbert space of an RSOS-model, introduced by Andrews, Baxter, and Forrester, can be viewed as a space of sequences (paths) {a_0,a_1,...,a_L}, with a_j-integers restricted by 1<=a_j<=ν, |a_j-a_{j+1}|=1, a_0=s, a_L=r. In this paper we introduce different basis which, as shown here, has the same dimension as that of an RSOS-model. Following McCoy et al, we

Lay Nam Chang, Yigao Liang, Ron L. Workman

The status of the Gerasimov-Drell-Hearn sum rules for polarized inclusive photo-production on nucleons is reviewed. It is shown that results from currently available data compare favorably with an estimate based on an extended current algebra. Implications for integrals of spin-dependent structure functions are also briefly discussed.

Hong-Jian He, Yu-Ping Kuang, Xiaoyuan Li

A general proof of the equivalence theorem in electroweak theories with the symmetry breaking sector described by the chiral Lagrangian is given in the $R_ξ$ gauge by means of the Ward-Takahashi identities. The precise form of the theorem contains a modification factor $C_{mod}$ associated with each external Goldstone boson similar to that in the standard mo

R. Shankar, H. Mathur

We begin with a prior observation by one of us that Thomas precession in the nonrelativistic limit of the Dirac equation may be attributed to a nonabelian Berry vector potential. We ask what object produces the nonabelian potential in parameter space, in the same sense that the abelian vector potential arising in the adiabatic transport of a nondegenerate le

M. Bonini, M. D&#39;Attanasio, G. Marchesini

The global chiral symmetry of a $SU(2)$ gauge theory is studied in the framework of renormalization group (RG). The theory is defined by the RG flow equations in the infrared cutoff $Ł$ and the boundary conditions for the relevant couplings. The physical theory is obtained at $Ł=0$. In our approach the symmetry is implemented by choosing the boundary conditi

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

The distribution of transverse energy, $E_T$, which accompanies deep-inelastic electron-proton scattering at small $x$, is predicted in the central region away from the current jet and proton remnants. We use BFKL dynamics, which arises from the summation of multiple gluon emissions at small $x$, to derive an analytic expression for the $E_T$ flow. One inter

Edward Farhi, Valentin V. Khoze, Krishna Rajagopal, Robert Singleton

We consider the classical equations of motion of $SU(2)$ gauge theory, without a Higgs field, in Minkowski space. We work in the spherical ansatz and develop a perturbative expansion in the coupling constant $g$ for solutions which in the far past look like freely propagating spherical shells. The topological charge $Q$ of these solutions is typically non-in

Masako Bando, K. -I. Izawa, Tomohiko Takahashi

We consider a minimal SO(10) unified model with horizontal Peccei-Quinn symmetry. The hierarchical structure of quark-lepton mass matrices is naturally implemented by the remnants of certain irrelevant terms. Georgi-Jarlskog relations are also realized due to the horizontal symmetry.

Matteo Beccaria

We consider the lattice formulation of bosonized quantum field theories. As a non trivial example, we study the two dimensional Gross-Neveu model. Analytical investigations and direct numerical simulation strongly suggest that the lattice model reproduces the continuum physics. Anticommuting fields are not required and there are not related doubling problems

Vladimir G. Pestov

In 1984 Milnor had shown how to deduce the Lie-Palais theorem on integration of infinitesimal actions of finite-dimensional Lie algebras on compact manifolds from general theory of regular Lie groups modelled on locally convex spaces. We show how, in the case of effective action, one can eliminate from Milnor&#39;s argument the abstract Lie-Cartan theorem, m

S. Flach, C. R. Willis

We analyze the effect of internal degrees of freedom on the movability properties of localized excitations on defect-free nonlinear Hamiltonian lattices by means of properties of a local phase space which is at least of dimension six. We formulate generic properties of a movability separatrix in this local phase space. We prove that due to the presence of in

S. Flach, G. Mutschke

We study the one-dimensional discrete $Φ^4$ model. We compare two equilibrium properties by use of molecular dynamics simulations: the Lyapunov spectrum and the time dependence of local correlation functions. Both properties imply the existence of a dynamical crossover of the system at the same temperature. This correlation holds for two rather different reg

M. J. M. de Jong, C. W. J. Beenakker

The low-frequency shot-noise power of a normal-metal-superconductor junction is studied for arbitrary normal region. Through a scattering approach, a formula is derived which expresses the shot-noise power in terms of the transmission eigenvalues of the normal region. The noise power divided by the current is enhanced by a factor two with respect to its norm

Ping Ao

The influence of a magnetic field on the tunneling of an electron out of a confining plane is studied by a path integral method. We map this 3-d problem on to a 1-d one, and find that the tunneling is strongly affected by the field. Without a perpendicular field the tunneling at zero temperature can be completely suppressed by a large parallel field, but in

J. K. Freericks, Mark Jarrell

The electron-phonon interaction corresponding to the Holstein model (with Coulomb repulsion) is simulated in infinite dimensions using a novel quantum Monte Carlo algorithm. The thermodynamic phase diagram includes commensurate charge-density-wave phases, incommensurate charge-density-wave phases, and superconductivity. The crossover from a weak-coupling pic

Wayne Hu, Naoshi Sugiyama

We present a thorough and detailed investigation of baryon isocurvature models including realistic thermal histories, \ie, late or partial reionization of the universe and compact object formation after standard recombination. Constraints on these models are imposed from spectral distortion in the cosmic microwave background (CMB), number fluctuations in gal

A. G. Weiss, T. Buchert

We report on a recent paper (Weiß \& Buchert 1993), where we carry out pencil beam constructions in a high-resolution simulation of the large-scale structure of galaxies. As an example we present the results for the case of ``Hot-Dark-Matter&#34; (HDM) initial conditions (with scale-free $n = 1$ power index on large scales and $Ω= 1$) as a representative of

J. P Gauntlett, J. A. Harvey

Paper is withdrawn and superseded by EFI-94-36 which will appear shortly with the new hep-th number hep-th/9407111 .

R. Timmermans, Th. A. Rijken, J. J. de Swart

A partial-wave analysis of all antiproton-proton scattering data below 925 MeV/c antiproton laboratory momentum is presented. The method used is adapted from the Nijmegen phase-shift analyses of pp and np scattering data. The Nijmegen 1993 antiproton-proton database, consisting of 3646 antiproton-proton scattering data, is presented and discussed. The best f

A. Sirlin

We discuss a simple method to evaluate the QCD corrections to $Δρ$. It assumes that the perturbative expansion in terms of $\ms$ parameters is meaningful and, unlike other studies, exploits significant available information concerning $\chass$ corrections. This approach leads to an enhancement of $\sim26\%$ relative to the conventional evaluation. QCD correc

N. N. Nikolaev, B. G. Zakharov

We study a novel property of large rapidity-gap events in deep inelastic scattering at HERA: splitting the pomeron into two jets in the photon-pomeron fusion reaction $γ^{*}\Pom \rightarrow q\bar{q}$. It gives rise to the diffraction dissociation of virtual photons into the back-to-back jets. We find that at large invariant mass $M$ of two jets, $M^{2}\gg Q^

Benni Reznik

The properties of canonical and microcanonical ensembles of a black hole with thermal radiation and the problem of black hole evaporation in 3-D are studied. In 3-D Einstein-anti-de Sitter gravity we have two relevant mass scales, $m_c=1/G$, and $m_p=(\hbar^2Λ/G)^{1/3}$, which are particularly relevant for the evaporation problem. It is argued that in the `w

James M. Nester, Roh Suan Tung, Vadim V. Zhytnikov

We describe a class of spinor-curvature identities which exist for Riemannian or Riemann-Cartan geometries. Each identity relates an expression quadratic in the covariant derivative of a spinor field with an expression linear in the curvature plus an exact differential. Certain special cases in 3 and 4 dimensions which have been or could be used in applicati

Lev Kofman, Dmitry Pogosayn

Few recent generations of cosmologists have solved non-local newtonian equations of the gravitational instability in an expanding universe. In this approach pancaking is the predominant form of first collapsing objects. Relativistic counterparts of these equations contain the electric and magnetic parts of the Weyl tensor. In the linear theory the magnetic p

Atsushi Moriwaki

In this note, we will give a partial answer for arithmetic analogues of Grothendieck&#39;s standard conjectures due to H. Gillet and C. Soule. (Remark : I changed the title of this note.)

Masato Shimono

An $N=2$ supersymmetric model using Kähler fields is proposed. It is a modified version of two-dimensional Benn-Tucker model. It indicates a geometrical origin of $N=2$ supersymmetry.

Yoshiki Kizukuri, Noriyuki Oshimo

$CP$ violating phenomena predicted by the minimal supersymmetric standard model are discussed in a case where the $CP$ violating phases in SUSY sector are not suppressed. The electric dipole moments of the neutron and the electron are large, but can be smaller than their experimental upper bounds if the scalar quarks and leptons are heavier than a few TeV. $

Yoshinori Nishino

We calculate the values of the second moment $M_2^s$ of the flavor-singlet structure function $F_2^s$ for the pion and the kaon in QCD sum rules, and investigate how the results depend on their flavor structure (quark contents). Our calculations give similar values of $M_2^s$ for these two mesons, because of cancellation among several non-small factors. We e

D. E. Soper

I compare our understanding selected topics in Multiparticle Dynamics at this meeting to what we knew at the 1983 Multiparticle Dynamics Symposium. I also discuss rapidity gap physics, a subject that has developed in the years since 1983

Jaume Garriga, Patrick Peter

The lensing properties of superconducting cosmic strings endowed with a time dependent pulse of lightlike current are investigated. The metric outside the core of the string belongs to the $pp$--wave class, with a deficit angle. We study the field theoretic bosonic Witten model coupled to gravity, and we show that the full metric (both outside and inside the

F. Bernardeau, L. Kofman

The properties of the probability distribution function of the cosmological continuous density field are studied. We present further developments and compare dynamically motivated methods to derive the PDF. One of them is based on the Zel&#39;dovich approximation (ZA). We extend this method for arbitrary initial conditions, regardless of whether they are Gau

W. J. Henney

The Doppler shifts of optical emission lines which have been scattered by surrounding dust and electrons can provide useful information about the kinematics, geometry and physical conditions of astrophysical flows. In principle, the scatterers can provide views of the line-emitting gas from different directions, allowing the 3-d velocity field of the emittin

Bernd Siebert, Gang Tian

We observe a general structure theorem for quantum cohomology rings, a non-homogeneous version of the usual cohomology ring encoding information about (almost holomorphic) rational curves. An application is the rigorous computation of the quantum cohomology of Grassmannians. As purely algebraic consequence we prove a beautiful formula of Vafa and Intriligato

Denis Juriev

There are investigated several objects of an INFINITE DIMENSIONAL GEOMETRY appearing from the second quantization of a free string. The paper contains 2 chapters: 1st is devoted to the infinite dimensional geometry of flag, fundamental and $\Pi$-spaces for Virasoro-Bott group and its nonassociative deformation defined by Gelfand-Fuchs 3-cocycle (Gelfand-Fuch

A. P. Balachandran, G. Bimonte, E. Ercolessi, G. Landi

Conventional discrete approximations of a manifold do not preserve its nontrivial topological features. In this article we describe an approximation scheme due to Sorkin which reproduces physically important aspects of manifold topology with striking fidelity. The approximating topological spaces in this scheme are partially ordered sets (posets). Now, in or

Brian Dolan

The renormalisation group equation for $N$-point correlation functions can be interpreted in a geometrical manner as an equation for Lie transport of amplitudes in the space of couplings. The vector field generating the diffeomorphism has components given by the $β$-functions of the theory. It is argued that this simple picture requires modification whenever

G. Dvali, Goran Senjanovi{ć}

We show that the minimal supergravity extension of the standard model automatically contains topologically stable electroweak strings if the hidden sector is invariant under the exact R-symmetry. These defects appear in the form of the semiglobal R-strings, which necessarily carry $Z$-flux inside their core. This result is independent from the particular str

Arjun Berera, Davison E. Soper

In diffractive jet production, two high energy hadrons A and B collide and produce high transverse momentum jets, while hadron A is diffractively scattered. Ingelman and Schlein predicted this phenomenon. In their model, part of the longitudinal momentum transferred from hadron A is delivered to the jet system, part is lost. Lossless diffractive jet producti

R. N. Mohapatra, A. Riotto

We show that a recently proposed extension of the MSSM can provide a scenario where both the cold and hot dark matter of the universe owe their origin to a single scale connected with the breakdown of the global B-L symmetry. The susy partner of the majoron and the light Majorana neutrinos are the cold and hot dark matter candidates respectively in this mode

D. J. Broadhurst, P. A. Baikov, V. A. Ilyin, J. Fleischer

The coefficient functions of the gluon condensate $<G^2>$, in the correlators of heavy-quark vector, axial, scalar and pseudoscalar currents, are obtained analytically, to two loops, for all values of $z=q^2/4m^2$. In the limiting cases $z\to0$, $z\to1$, and $z\to-\infty$, comparisons are made with previous partial results. Approximation methods, based on th

Thomas D. Cohen, Manoj K. Banerjee, Marina Nielsen, Xuemin Jin

Classical considerations suggest that the probability distribution $P(R)$, where $R$ is the ratio of neutral pions to total pions emitted from a disoriented chiral condensate (which has been hypothesized to form in heavy ion reactions) is $R^{-1/2}/2$. Quantum mechanical isospin correlations between the condensate and the remainder of the system can alter th

M. Anselmino, F. Caruso, F. Murgia, M. R. Negrao

Massless perturbative QCD forbids, at leading order, the exclusive annihilation of proton-antiproton into some charmonium states, which, however, have been observed in the $p\bar p$ channel, indicating the significance of higher order and non perturbative effects in the few GeV energy region. The most well known cases are those of the $^1S_0$ ($η_c$) and the

J. Baacke, H. So, A. Suerig

We present results for the fermion determinant in an external Yukawa-coupled scalar field, a quantity relevant to instanton and sphaleron transition rates as well as bubble nucleation occuring in the electroweak phase transition when the scalar field is identified with the Higgs field. We calculate the determinant exactly and find an approximation (essential

V. A. Bednyakov

It is shown that the D--meson, whose light quark is the initial-pion valence quark and whose charmed quark is produced in annihilation of valence quarks and has got a large enough momentum, is really a leading meson in reactions like $π^- p -> DX$. If such annihilation of valence quarks from initial hadrons is impossible there must be no distinct leading eff

Robert H. Brandenberger, Anne-Christine Davis

The classical evolution equations of the Abelian Higgs model are studied at temperatures below the Ginsburg temperature of a phase transition which is assumed to be second order. It is shown that the initial thermal fluctuations provide a domain structure which is stable against late time fluctuations. This result lends support to the Kibble mechanism for th

Carl H. Albright, Satyanarayan Nandi

A new procedure proposed recently enables one to start from the quark and lepton mass and mixing data at the low scale and construct mass matrices which exhibit simple SO(10) structure at the SUSY GUT scale. We elaborate here on the numerical details which led us to an SO(10) model for the quark and lepton mass matrices that explain the known quark data at t

Lee Lin

According to one-loop perturbation theory, fermions whose masses are totally generated from Yukawa couplings do not decouple in the heavy mass limit. We investigate this issue nonperturbatively in the strong coupling regime of the chiral $U(1)$ mirror-fermion model in four dimensions. Our numerical results, obtained on $6^3\cdot 16$, $6^3\cdot 24$ and $8^3\c

L. Del Debbio A. Di Giacomo, G. Paffuti

We explicitly construct a monopole creation operator: its vacuum expectation value is an order parameter for dual superconductivity, in that, if different from zero, it signals a spontaneous breaking of the $U(1)$ symmetry corresponding to monopole charge conservation. This operator is tested by numerical simulations in compact $U(1)$ gauge theory. Our const

G. Schierholz

It is argued that QCD might solve the strong CP problem on its own. To test this idea, a lattice simulation suggests itself. In view of the difficulty of such a calculation we have, as a first step, investigated the problem in the $CP^3$ model. The $CP^3$ model is in many respects similar to QCD. In this talk I shall present some first results of our calcula

M. Kruczenski, L. E. Oxman, M. Zaldarriaga

We consider the generation of entropy when particle pairs are created at a cosmological level. Making a reduction via the particle number basis, we compute the classical limit for the entropy generation due to the evolution of the matter field fluctuations (squeeze transformation), obtaining that it is linear in the squeeze parameter for a general class of i

Osamu Yasuda

Possible breakdown of the universality of the gravitational couplings to different neutrino flavors can be tested in long-baseline neutrino-oscillation experiments, such as a proposed experiment at SOUDAN 2 or one at the DUMAND project. Such a breakdown could be detected with sensitivity to the order of $10^{-14}$ or $10^{-15}$. For generic case of neutrino

N. Prokof&#39;ev

We show that ion masses in superfluid $^3$He ought to be enormously enhanced (by a factor of 100) as compared with the same ion masses in $^4$He measured at low temperature. We calculate precisely the dependence of the effective mass on pressure in $^3$He-B, and show that the coherent (ballistic) motion of ions in $^3$He-B can be studied experimentally at $

E. Mueller-Hartmann, C. I. Ventura

We analyze the motion of a single hole on a Néel background, neglecting spin fluctuations. Brinkman and Rice studied this problem on a cubic lattice, introducing the retraceable-path approximation for the hole Green&#39;s function, exact in a one-dimensional lattice. Metzner et al. showed that the approximationalso becomes exact in the infinite-dimensional l

V. V. Flambaum, M. Yu. Kuchiev, O. P. Sushkov

Long-range $(r \sim p_F^{-1} \gg lattice \ spacing)$ spin-wave exchange produces a very strong pairing of the holes. The different symmetry solutions of BCS-type equation for the superconducting gap $Δ$ are found. The most strong pairing corresponds to $d$-wave symmetry. The physical reasons for the strong pairing are: 1)large velocity of the spin-wave, 2) a

M. Yu. Kuchiev, O. P. Sushkov

Several series of shallow large-size ($l \gg lattice~ spacing$) two-hole bound states are found in the two-dimensional t-J model. Their binding energies depend exponentially on the inverse value of the hole-spin-wave coupling constant. Their parity is connected with the angular wave function in a nonstandard way. The possible role of these states in the form

A. H. Castro Neto, A. O. Caldeira

We study the mobility of a particle coupled to a one dimensional interacting fermionic system, a Luttinger liquid. We bosonize the Luttinger liquid and find the effective interaction between the particle and the bosonic system. We show that the dynamics of this system is completely equivalent to the acoustic polaron problem where the interaction has purely e

Bruce M. Boghosian, Washington Taylor

A complete formulation is given of an exact kinetic theory for lattice gases. This kinetic theory makes possible the calculation of corrections to the usual Boltzmann / Chapman-Enskog analysis of lattice gases due to the buildup of correlations. It is shown that renormalized transport coefficients can be calculated perturbatively by summing terms in an infin

W. J. Henney, A. C. Raga, D. J. Axon

Detailed comparisons are made between observations of scattered light upstream of the head of the HH~1 jet and predictions of simple scattering models. It is shown that, in order to unambiguously determine the velocity of the head of the jet (bow shock) with respect to the upstream dust, existing spectroscopic observations are insufficient and that spectropo

W. J. Henney

A general theoretical framework is developed for interpreting spectropolarimetric observations of optically thin emission line scattering from small dust particles. Spatially integrated and spatially resolved line profiles of both scattered intensity and polarization are calculated analytically from a variety of simple kinematic models. These calculations wi

Mirek Giersz, Douglas C. Heggie

This paper presents and analyses statistical results from a large number of $N$-body simulations of isolated systems with equal masses, in which $250\le N\le 2000$. It concentrates on the phase starting around the end of core collapse, when binaries start to play a crucial role. Interactions of hard binaries are consistent with the Spitzer (1987) cross secti

T. Buchert

Fundamental assumptions which form the basis of models for large-scale structure in the Universe are sketched in light of a Lagrangian description of inhomogeneities. This description is introduced for Newtonian self-gravitating flows. On its basis a Lagrangian perturbation approach is discussed and compared with the standard Eulerian theory of gravitational

Andrew Gould

The optical depth to microlensing toward M31 due to known stars in the disk of M31 itself is $τ\sim 2\times 10^{-7}e^{-r/d}$ where $d$ is the disk scale length and $r$ is the distance along the major axis. Thus, there can be significant lensing toward the M31 disk even if M31 contains no dark compact objects. The optical depth has a strong dependence on azim

Masa-Nori Ishida

In the previous paper, we describe the intersection complexes of a toric variety as a finite complex of graded exterior modules on the associated fan. In this second part, we rewrite it explicitly by the barycentric subdivision of the fan. We get the decomposition theorem of the intersection homologies for a barycentric subdivision of a fan in the case of mi

Masa-Nori Ishida

We describe the intersection complex of any perversity of a toric variety completely in terms of the associated fan. It is described by a finite complex of finite dimensional graded vector spaces which we call graded exterior modules. The intersection complexes of the middle perversity are treated in the second part following this article.

S. R. White, R. M. Noack, D. J. Scalapino

Using numerical results from a density matrix renormalization group study as a guide, we develop a resonating valence bond (RVB) theory for coupled Heisenberg chains. We argue that simple topological effects mandate a short-range RVB description of systems with an even number of chains $n_c$, with a spin gap, short-range correlations, and confinement of topo

N. Deshpande, Xiao-Gang He

We study in next-to-leading order QCD hadronic penguin $B$ decays in the Standard and two-Higgs-doublet models. Although the gluonic penguin dominates, we find the electroweak contribution non-negligible. In the Standard Model, the branching ratio for $B \rightarrow X_s ϕ$ is predicted to be in the range $(0.6\sim 2)\times 10^{-4}$. The ranges of branching r

A. Yu. Alekseev, H. Grosse, V. Schomerus

Motivated by a recent paper of Fock and Rosly \cite{FoRo} we describe a mathematically precise quantization of the Hamiltonian Chern-Simons theory. We introduce the Chern-Simons theory on the lattice which is expected to reproduce the results of the continuous theory exactly. The lattice model enjoys the symmetry with respect to a quantum gauge group. Using

K. Werner

By colliding ultrarelativistic ions, one achieves presently energy densities close to the critical value, concerning the formation of a quark-gluon-plasma. This indicates the importance of fluctuations and the necessity to go beyond the investigation of average events. Therefore, we introduce a percolation approach to model the final stage ($τ> 1$ fm/c) of i

Jindřich Zapletal

We improve some ancient results of Velickovic on the cut and choose (c&c) game on complete Boolean algebras. (1) If Nonempty has a winning strategy for c&c game on $B$ then $B$ is semiproper. (2) If Nonempty has a winning strategy and $B$ has $2^{\aleph _0}$ -c.c. then Nonempty has a winning strategy in the descending chain game. (3) Cons ($B$ is $\aleph _1$

Jindřich Zapletal

We study cohabitation of the poset $P_S$ shooting a club through a given stationary subset $S$ of $ω_1$ with finite conditions with other forcings. Sample results: (1) $P_S$ &#34;sometimes&#34; preserves presaturatedness of $NS_{ω_1}$ (2) $P_S=P_T$ if $S=T mod NS_{ω_1}$ (in Boolean algebra sense) (3) Cons ( one can embed $Q,$ the poset adding $\aleph _1$ Coh

Thomas E. Leathrum

The collection of branches (maximal linearly ordered sets of nodes) of the tree ${}^{<ω}ω$ (ordered by inclusion) forms an almost disjoint family (of sets of nodes). This family is not maximal -- for example, any level of the tree is almost disjoint from all of the branches. How many sets must be added to the family of branches to make it maximal? This quest

C. R. Hagen

The question as to whether helicity conservation in spin one-half Aharonov Bohm scattering is sufficient in itself to determine uniquely the form of the spinor wave function near the origin is examined. Although it is found that a one parameter family of solutions is compatible with this conservation law, there must nonetheless be singular solutions which br

Jintai Ding, Pavel Etingof

We construct central elements in a completion of the quantum affine algebra at the critical level c=-g from the universal R-matrix (g being the dual Coxeter number of the corresponding simple Lie algebra), using the method of Reshetikhin and Semenov-Tian-Shansky. This construction defines an action of the Grothendieck algebra of the category of finite-dimens

A. Bartoli, J. Julve

Higher Derivative (HD) Field Theories can be transformed into second order equivalent theories with a direct particle interpretation. In a simple model involving abelian gauge symmetries we examine the fate of the possible gauge fixings throughout this process. This example is a useful test bed for HD theories of gravity and provides a nice intuitive interpr

Klaus Kirsten, Sergei Odintsov

The one-loop effective potential in $2D$ dilaton gravity in conformal gauge on the topologically non-trivial plane $\reals \times S^1$ and on the hyperbolic plane $H^2/Γ$ is calculated. For arbitrary choice of the tree scalar potential it is shown, that the one-loop effective potential explicitly depends on the reference metric (through the dependence on the

G. Au, B. Spence

We present new covariant phase space formulations of superparticles moving on a group manifold, deriving the fundamental Poisson brackets and current algebras. We show how these formulations naturally generalise to the supersymmetric Wess-Zumino-Witten models.

Daniel Boyanovsky, Richard Holman, Da-Shin Lee, João P. Silva

Thermal activation is mediated by field configurations that correspond to saddle points of the energy functional. The rate of probability flow along the unstable functional directions, i.e the activation rate, is usually obtained from the imaginary part of a suitable analytic continuation of the equilibrium free energy. In this note we provide a real-time, n

C. J. Benesh, J. Qiu, J. P. Vary

We examine the production of J/$Ψ$ mesons in high energy hadron-nucleus collisions using models that account for both the initial state modification of parton distributions in nuclei and the final state interaction of the produced $c\bar c$ pairs. We show that, at the energies of current fixed target experiments, J/$Ψ$ production through quark-antiquark anni

R. Kaminski, L. Lesniak, J. -P. Maillet

A separable potential formalism is used to describe the $ππ$ and $K\overline{K}$ interactions in the scalar-isoscalar states in the energy range from the $ππ$ threshold up to 1.4 GeV. Introduction of relativistic propagators into a system of Lippmann-Schwinger equations leads to a very good description of the data ($χ^{2}=0.93$ per one degree of freedom). Th

John F. Donoghue

I review the present state of our knowledge about the masses and weak mixing elements of the u, d, s quarks. This is the written version of lectures given in the 1993 Theoretical Advanced Study Institute (TASI).

S. V. Faleev, P. G. Silvestrov

Instanton -- antiinstanton pair is considered as a source of singularity at the Borel plane for the ground state energy of anharmonic oscillator. The problem of defining the short range instanton -- antiinstanton interaction reduces to calculation of a smooth part of the Borel function, which cannot be found without explicit calculation of several terms of o

Leonard S. Kisslinger, Siwen Wang

We have reexamined the elastic pion form factor over a broad range of momentum transfers with the mass evolution from current quark to constituent quark being taken into account. We have also studied the effect of Sudakov form factors, of anomalous quark magnetic moments and of alternative soft wave functions. Our calculation shows a power-law falloff from t

Richard C. Brower, Yue Shen, Chung-I Tan

We propose an extended Quantum Chromodynamics (XQCD) Lagrangian in which the fermions are coupled to elementary scalar %$σ$ and $π$ fields through a Yukawa coupling which preserves chiral invariance. Our principle motivation is to find a new lattice formulation for QCD which avoids the source of critical slowing down usually encountered as the bare quark mas