August 1996 arXiv papers — page 8

Simonetta Frittelli, Luis Lehner, Carlo Rovelli

We compute the complete spectrum of the area operator in the loop representation of quantum gravity, using recoupling theory. This result extends previous derivations, which did not include the ``degenerate'' sector, and agrees with the recently computed spectrum of the connection-representation area operator.

Guy D. Moore, Neil G. Turok

We investigate the thermodynamics and dynamics of the electroweak phase transition by modelling the infrared physics with classical Yang-Mills Higgs theory. We discuss the accuracy of this approach and conclude that, for quantities whose determination is dominated by the infrared, the classical method should be correct up to parametrically suppressed (ie O(a

Dae Sung Hwang, Youngjai Kiem, Dahl Park

We provide a method to determine the motion of a classical massive particle in a background geometry of 2-dimensional gravity theories, for which the Birkhoff theorem holds. In particular, we get the particle trajectory in a continuous class of 2-dimensional dilaton gravity theories that includes the Callan-Giddings-Harvey-Strominger (CGHS) model, the Jackiw

R. D. Blum, K. Sellgren, D. L. DePoy

New and existing K-band spectra for 19 Galactic center late-type stars have been analyzed along with representative spectra of disk and bulge M giants and supergiants. Absorption strengths for strong atomic and molecular features have been measured. The Galactic center stars generally exhibit stronger absorption features centered near Na I (2.206 mic) and Ca

J. Grundberg, U. Lindstrom, M. Rocek

We consider theories with degenerate kinetic terms such as those that arise at strong coupling in $N=2$ super Yang-Mills theory. We compute the components of generalized $N=1,2$ supersymmetric sigma model actions in two dimensions. The target space coordinates may be matter and/or Yang-Mills superfield strengths.

Nathan Seiberg

We study (non-renormalizable) five dimensional supersymmetric field theories. The theories are parametrized by quark masses and a gauge coupling. We derive the metric on the Coulomb branch exactly. We use stringy considerations to learn about new non-trivial interacting field theories with exceptional global symmetry $E_n$ ($E_8$, $E_7$, $E_6$, $E_5=Spin(10)

Andrew Steane

A set of quantum error correcting codes based on classical Reed-Muller codes is described. The codes have parameters [[n,k,d]] = [[2^r, 2^r - C(r,t) - 2 sum_{i=0}^{t-1} C(r,i), 2^t + 2^{t-1} ]].

L. T. Handoko

The contributions of $s-$channel Higgs in $l^+ l^- \rightarrow q \bar{q}$ processes in the general lepton collider ($l^+ l^-$ collider) within Standard Model is studied. A new idea to extract the contribution by using the data from both electron and future heavy-lepton colliders at same center-of-mass energy is proposed. Deviations due to the $s-$channel Hig

Juan Garcia-Bellido, Andrew R Liddle, David H Lyth, David Wands

We discuss the appropriate normalization of modes required to generate a homogeneous random field in an open Friedmann-Robertson-Walker universe. We consider scalar random fields and certain tensor random fields that can be obtained by covariantly differentiating a scalar. Modes of interest fall into three categories: the familiar sub-curvature modes, the mo

C. A. da Rocha, M. R. Robilotta, J. L. Ballot

We evaluate the two pion exchange contribution to the nucleon-nucleon potential in configuration space using a "minimal chiral model" containing only pions and nucleons. We argue that this model has nowadays a rather firm conceptual basis, which entitles it to become a standard ingredient of any modern potential. The main features of this model is th

M. Kibler, L. G. Mardoyan, G. S. Pogosyan

This article deals with a nonrelativistic quantum mechanical study of a dynamical system which generalizes the isotropic harmonic oscillator system in three dimensions. The problem of interbasis expansions of the wavefunctions is completely solved. A connection between the generalized oscillator system (projected on the z-line) and the Morse system (in one d

Siddhartha Sahi

Symmetric Jack polynomials arise naturally in several contexts, including statistics, physics, combinatorics, and representation theory. They are pairwise orthogonal with repsect to two different inner products, the first defined by integration over an n-dimensional torus, and the second defined via a power series expansion. The nonsymmetric analogs of Jack

G. E. Brown, C. M. Ko, G. Q. Li

Kaon production and kaon flow in heavy-ion collisions at SIS energies are analyzed using the relativistic transport model. The experimental data are found to be consistent with the scenario that kaon scalar (before being cut down by the range term) and vector mean field potentials are about 1/3 of that of nucleons in the Walecka model. This also explains the

Su H. Lee, H. Kim

We propose a new interpolating field for S$_{11}$(1535) to determine its mass from QCD sum rules. In the nonrelativistic limit, this interpolating field dominantly reduces to two quarks in the s-wave state and one quark in the p-wave state. An optimization procedure, which makes use of a duality relation, yields the interpolating field which overlaps strongl

T. Hatsuda

We summarize the current theoretical and experimental status of the spectral changes of vector mesons ($ρ$, $ω$, $ϕ$) at finite baryon density. Various approaches including QCD sum rules, effective theory of hadrons and bag models show decreasing of the vector meson masses in nuclear matter. Possibility to detect the mass shift through lepton pairs in $γ-A$,

Byunghan Kim

Let T be a countable, small simple theory. In this paper, we prove for such T, the notion of Lascar Strong type coincides with the notion of a strong type,over an arbitrary set.

Piljin Yi

Dynamics of many supersymmetric monopoles are studied in the low energy approximation. A conjecture for the exact moduli space metric is given for all collections of fundamental monopoles of distinct type, and various partial confirmations of the conjecture are discussed. Upon the quantization of the resulting multi-monopole dynamics in the context of $N=4$

K. Davis

In this article we examine some points in the moduli space of M-Theory at which there arise enhanced gauge symmetries. In particular, we examine the ``trivial" points of enhanced gauge symmetry in the moduli space of M-Theory on $S^{ 1 } \times S^{ 1 } / { \bf Z }_{ 2 }$ as well as the points of enhanced gauge symmetry in the moduli space of M-Theory on

Robert Marnelius

As previously shown BRST singlets |s> in a BRST quantization of general gauge theories on inner product spaces may be represented in the form |s>=e^{[Q, ψ]} |ϕ> where |ϕ> is either a trivially BRST invariant state which only depends on the matter variables, or a solution of a Dirac quantization. ψis a corresponding fermionic gauge fixing operator. In this pa

T. M. Aliev, N. K. Pak, M. Savci

We calculate the strong coupling constants g_(P^(**)P^(*)π), where P^(**)(D^(**), B^(**)) is the 1^+ p-wave state, in the framework of the light cone QCD sum rules, and using these values of g_(P^(**)P^(*) pi, we compute the hadronic decay widths for D^(**) -> D^* pi and B^(**) -> B^* pi.

E. H. Simmons

A flavor-universal extension of the strong interactions was recently proposed in response to the apparent excess of high-$E_T$ jets in the inclusive jet spectrum measured at the Tevatron. The color octet of massive gauge bosons (`colorons') that is present in the low-energy spectrum of the model's Higgs phase is studied here. Experimental constraints

O. I. Yakovlev

We discuss an application of QCD sum rules to the heavy baryons $Λ_Q$ and $Σ_Q$. The predictions for the masses of heavy baryons, residues and Isgur-Wise function are presented. The new results on two loop anomalous dimensions of baryonic currents and QCD radiative corrections (two- and three- loop contributions) to the first two Wilson coefficients in OPE a

M. K. Volkov, C. Weiss

We construct a chiral Lagrangian containing besides the usual pion field (pi) also its first radial excitation (pi'). The Lagrangian is derived by bosonization of a Nambu--Jona-Lasinio quark model with separable non-local interactions, with form factors corresponding to 3-dimensional ground and excited state wave functions. Chiral symmetry breaking is go

S. Hegyi

A three-parameter discrete distribution is developed to describe the multiplicity distributions observed in total- and limited phase space volumes in different collision processes. The probability law is obtained by the Poisson transform of the KNO scaling function derived in Polyakov's similarity hypothesis for strong interactions as well as in perturba

E. Norrbin, T. Sjöstrand

Several distinct colour flow topologies are possible in multiparton configurations. A method is proposed to find the correct topology, based on a minimization of the total transverse momentum of produced particles. This method is studied for three-jet $Z^0 \to q\overline{q} g$ and four-jet $W^+W^- \to q_1\overline{q}_2q_3\overline{q}_4$ events. It is shown h

Philippe de Forcrand, Tetsuya Takaishi

Three possibilities to speed up the Hybrid Monte Carlo algorithm are investigated. Changing the step-size adaptively brings no practical gain. On the other hand, substantial improvements result from using an approximate Hamiltonian or a preconditioned action.

The MILC Collaboration, C. Bernard, T. Blum, T. DeGrand

We describe the current status of the MILC collaboration computation of $f_B$, $f_{B_s}$, $f_D$, $f_{D_s}$ and their ratios. Progress over the past year includes: better statistics and plateaus at $β=6.52$ (quenched), $β=5.6$ ($N_F=2$) and $β=5.445$ ($N_F=2$), new runs with a wide range of dynamical quark masses at $β=5.5$ ($N_F=2$), an estimate of the syste

Myunggyu Kim, Seyong Kim

We calculate one-loop correction to the axial charges of the octet baryons using quenched chiral perturbation theory, in order to understand chiral behavior of the axial charges in quenched approximation to quantum chromodynamics (QCD). In contrast to regular behavior of the full QCD chiral perturbation theory result, $c_0+c_{l2}m_π^2\,\ln{m_π^2}+\cdots$, we

Y. Iwasaki, K. Kanaya, T. Kaneko, T. Yoshié

We study the scaling property of the ratio of the critical temperature $T_c$ to the square root of the string tension $σ$ in the SU(3) pure gauge theory using a renormalization group improved action. We first determine the critical coupling $β_c$ on lattices with temporal extension $N_t=4$ and 6, and then calculate the static quark potential at the critical

S. Aid

Using the H1 detector at HERA, charged particle multiplicity distributions in deep inelastic ep scattering have been measured over a large kinematical region. The evolution with $W$ and $Q^2$ of the multiplicity distribution and of the multiplicity moments in pseudorapidity domains of varying size is studied in the current fragmentation region of the hadroni

Abhay Ashtekar, Jiri Bicak, Bernd G. Schmidt

Gravitational waves with a space-translation Killing field are considered. In this case, the 4-dimensional Einstein vacuum equations are equivalent to the 3-dimensional Einstein equations with certain matter sources. This interplay between 4- and 3- dimensional general relativity can be exploited effectively to analyze issues pertaining to 4 dimensions in te

Abhay Ashtekar, Jiri Bicak, Bernd G. Schmidt

The asymptotic behavior of Einstein-Rosen waves at null infinity in 4 dimensions is investigated in {\it all} directions by exploiting the relation between the 4-dimensional space-time and the 3-dimensional symmetry reduction thereof. Somewhat surprisingly, the behavior in a generic direction is {\it better} than that in directions orthogonal to the symmetry

Yoav Peleg, Sukanta Bose, Leonard Parker

We study numerically the collapse of massless scalar fields in two-dimensional dilaton gravity, both classically and semiclassically. At the classical level, we find that the black hole mass scales at threshold like $M_{\rm bh} \propto |p-p^*|^{\gamma}$, where $\gamma \simeq 0.53$. At the semiclassical level, we find that in general $M_{\rm bh}$ approaches a

Winfried Zimdahl, Josep Triginer, Diego Pavon

Particle production processes in the expanding universe are described within a simple kinetic model. The equilibrium conditions for a Maxwell-Boltzmann gas with variable particle number are investigated. We find that radiation and nonrelativistic matter may be in equilibrium at the same temperature provided the matter particles are created at a rate that is

G. 't Hooft

The fact that in Minkowski space, space and time are both quantized does not have to be introduced as a new postulate in physics, but can actually be derived by combining certain features of General Relativity and Quantum Mechanics. This is demonstrated first in a model where particles behave as point defects in 2 space dimensions and 1 time, and then in the

Yaroslav M. Blanter, Gerd Schön, Andrei D. Zaikin

We investigate a chain of capacitively coupled Josephson junctions in the regime where the charging energy dominates over the Josephson coupling, exploiting the analogy between this system and a multi-dimensional crystal. We find that the current-voltage characteristic of the current-driven chain has a staircase shape, beginning with an (insulating) non-zero

J. C. J. Paasschens, P. W. Brouwer, C. W. J. Beenakker

A random-matrix theory is presented for the reflection of light by a disordered medium backed by a phase-conjugating mirror. Two regimes are distinguished, depending on the relative magnitude of the inverse dwell time of a photon in the disordered medium and the frequency shift acquired at the mirror. The qualitatively different dependence of the reflectance

Mitake Miyazaki, Yasumasa Hasegawa

We study theoretically the transition temperature of a quasi-one-dimensional anisotropic superconductor in a magnetic field, which is thought to be realized in organic conductors,(TMTSF)2X. In the weak field limit,-dH_c2/dT for the anisotropic singlet is shown to be \sqrt{3} times larger than that for the anisotropic triplet in the case of attractive interac

M. T. Batchelor

A brief review is given of recent developments in the study of surface critical phenomena from the viewpoint of exactly solved lattice models. These developments include exact results for the polymer adsorption transition and the surface critical exponents of the eight-vertex model.

Christine Doran

Quoted speech is often set off by punctuation marks, in particular quotation marks. Thus, it might seem that the quotation marks would be extremely useful in identifying these structures in texts. Unfortunately, the situation is not quite so clear. In this work, I will argue that quotation marks are not adequate for either identifying or constraining the syn

Ted Pedersen

Statistical methods for automatically identifying dependent word pairs (i.e. dependent bigrams) in a corpus of natural language text have traditionally been performed using asymptotic tests of significance. This paper suggests that Fisher's exact test is a more appropriate test due to the skewed and sparse data samples typical of this problem. Both theor

Michael Loewenstein, Richard Mushotzky

Using X-ray temperature and surface brightness profiles of the hot intracluster medium derived from ASCA and ROSAT observations we place constraints on the dark matter and baryon fraction distributions in the poor clusters Abell 1060 and AWM 7. Although their total mass distributions are similar, AWM 7 has twice the baryon fraction of Abell 1060 in the best-

R. Cid Fernandes

It is now eleven years since Terlevich \& Melnick first proposed an `AGN without black-holes' model, an idea which since then evolved into what is now called the starburst model for AGN. This model has been the subject of much debate in the last decade, with observational evidence both for and against it further fuelling the controversy. Can we after all

Alan M. Levine, Hale Bradt, Wei Cui, J. G. Jernigan

The All-Sky Monitor on the Rossi X-ray Timing Explorer has been monitoring the sky in the 1.5 - 12 keV band since late February. The instrument consists of three coded-aperture cameras which can be rotated to view different regions by a motorized drive assembly. Intensities of ~100 known sources are obtained via least-square fits of shadow patterns to the da

A. C. Layden, R. B. Hanson, S. L. Hawley, A. R. Klemola

We present new statistical parallax solutions for the absolute magnitude and kinematics of RR Lyrae stars. New proper motion, radial velocity, and abundance data are used; the new data set is 50% larger, and of higher quality, than previously available data sets. Based on an a priori kinematic study, we separate the stars into halo and thick disk sub-populat

Y. Mellier, B. Fort

Recent weak lensing observations have pushed the use of 4 meter-class telescopes to the limits of their capabilities with exposure times exceeding several hours. The leading idea is that the surface density of faint galaxies up to very faint magnitude ($B > 28-30$) raises continuously thus potentially offering a dense template of distant sources whose intens

Z. Kuncic, E. G. Blackman, M. J. Rees

The range of microphysical and global dynamical timescales in the central regions of Active Galactic Nuclei (AGN) is sufficiently wide to permit the existence of multiphase structure. In particular, very dense, cool clouds can coexist with a hot, magnetically-dominated medium and can thereby efficiently reprocess the continuum radiation generated in this pri

Ori J. Ganor

The low-energy limit of the 6D non-critical string theory with $N=1$ SUSY and $E_8$ chiral current algebra compactified on $T^2$ is generically an $N=2$ $U(1)$ vector multiplet. We study the analog of the Seiberg-Witten solution for the low-energy effective action as a function of $E_8$ Wilson lines on the compactified torus and the complex modulus of that t

N. Kidonakis, J. Smith, R. Vogt

We study how next-to-leading logarithms modify predictions from leading logarithmic soft-gluon resummation in the heavy quark production cross section near threshold. Numerical results are presented for top quark production at the Fermilab Tevatron and bottom quark production at fixed-target energies.

Steven S. Gubser, Igor R. Klebanov

Recently Das and Mathur found that the leading order Hawking emission rate of neutral scalars by near-extremal $D=5$ black holes is exactly reproduced by a string theoretic model involving intersecting D-branes. We show that the agreement continues to hold for charged scalar emission. We further show that similar agreement can be obtained for a class of near

C. Gomez, R. Hernandez, E. Lopez

Global geometry of $K3$-fibration Calabi-Yau threefolds, with Hodge number $h_{2,1}=r+1$, is used to define $N=4$ softly broken $SU(r+1)$ gauge theories, with the bare coupling constant given by the dual heterotic dilaton, and the mass of the adjoint hypermultiplet given by the heterotic string tension. The $U(r+1)$ Donagi-Witten integrable model is also der

W. Fulton, R. Pandharipande

These are notes from a jointly taught class at the University of Chicago and lectures by the first author in Santa Cruz. Topics covered include: construction of moduli spaces of stable maps, Gromov-Witten invariants, quantum cohomology, and examples. These notes will appear in the proceedings of the 1995 Santa Cruz conference.

Gordon Chalmers, Amihay Hanany

The coulomb branch of $N=4$ supersymmetric Yang-Mills gauge theories in $d=2+1$ is studied. A direct connection between gauge theories and monopole moduli spaces is presented. It is proposed that the hyper-Kähler metric of supersymmetric $N=4$ $SU(N)$ Yang-Mills theory is given by the charge $N$ centered moduli space of BPS monopoles in $SU(2)$. The theory i

Jennifer A. Adams, Graham G. Ross, Subir Sarkar

We identify a new mechanism in supergravity theories which leads to successful inflation without any need for fine tuning. The simplest model yields a spectrum of density fluctuations tilted away from scale-invariance and negligible gravitational waves. We demonstrate that this is consistent with the observed large-scale structure for a cold dark matter domi

N. N. Nikolaev, W. Schaefer, B. G. Zakharov

We discuss the factorization breaking effects caused by the contribution to large rapidity gap events from DIS on secondary reggeons. Based on the triple-Regge phenomenology of hadronic diffraction dissociation, we present estimates for the flux and structure function of the f reggeon. The kinematical x_Pom-beta correlation is shown to modify substantially t

Karl Strobl

We derive various consistency requirements for Vachaspati-Vilenkin type Monte-Carlo simulations of cosmic string formation or disclination formation in liquid crystals. We argue for the use of a tetrakaidekahedral lattice in such simulations. We also show that these calculations can be carried out on lattices which are formally infinite, and do not necessita

Masahiro Fukushima, Shoichi Sasaki, Hideo Suganuma, Atsunori Tanaka

We generate a random instanton vacuum with various densities and size distributions. We perform numerically the maximally abelian gauge fixing of these configurations in order to find monopole trajectories induced by instantons. We find that instanton-induced monopole loops form enormous clusters occupying the whole physical volume, provided instantons are s

R. Dijkgraaf, G. Moore, E. Verlinde, H. Verlinde

In this note we prove an identity that equates the elliptic genus partition function of a supersymmetric sigma model on the N-fold symmetric product $M^N/S_N$ of a manifold M to the partition function of a second quantized string theory on the space $M \times S^1$. The generating function of these elliptic genera is shown to be (almost) an automorphic form f

ZEUS Collaboration, M. Derrick et al

The reaction $γp \rightarrow ωp$ $(ω\rightarrow π^+π^-π^0$ and $π^0\rightarrowγγ)$ has been studied in $ep$ interactions using the ZEUS detector at photon-proton centre-of-mass energies between $70$ and $90 GeV$ and $|t| < 0.6 GeV^2$, where $t$ is the squared four momentum transferred at the proton vertex.The elastic \ome photoproduction cross section has be

David J. Summers

At the Tevatron the transverse mass is used to separate on mass shell from off mass shell W production; and the rate of off mass shell W production gives a measure of the W width. We look at alternative variables to see if the separation of on and off mass shell W&#39;s can be improved, and hence give a better measure of the W width. We find that the transve

R. van Ojik, H. J. A. Röttgering, C. L. Carilli, G. K. Miley

We present the discovery and detailed observations of the radio galaxy 1243+036 (=4C 03.24) at a redshift of $z=3.57$. The most spectacular feature of 1243+036 is the presence of a Ly$α$ halo of luminosity $\sim10^{44.5}$ ergs s$^{-1}$ which extends over$\sim20&#39;&#39;$ (135 kpc). The narrow band imaging and the high resolution spectroscopy show that the L

K. Tsushima, A. Sibirtsev, A. W. Thomas

Results for the energy dependence of the elementary kaon production cross sections in proton-proton collisions are reported. Calculations are performed within an extended version of the resonance model which was used for the previous studies of elementary kaon production in pion-nucleon and pion-$\Delta$ collisions. Although the model treatment is within the

Haye Hinrichsen

We study two models with n equivalent absorbing states that generalize the Domany-Kinzel cellular automaton and the contact process. Numerical investigations show that for n=2 both models belong to the same universality class as branching annihilating walks with an even number of offspring. Unlike previously known models, these models have no explicit parity

D. V. Fedorov, A. S. Jensen

We introduce an approach, based on the coordinate space Faddeev equations, to solve the quantum mechanical three-body Coulomb problem in the continuum. We apply the approach to compute measured properties of the first two $0^+$ levels in $^{12}$C, including the width of the excited level, in a 3$α$-particle model. We use the two-body interaction which reprod

Kang-Hun Ahn, K. J. Chang

We calculate in an analyical fashion the energies and net spins of skyrmions in fractional quantum Hall systems, based on the suggestion that skyrmion states are spontaneously $L_Z$ and $S_Z$ symmetry-breaking states. The quasihole-skyrmion state with a charge $-e/3$ around $ν$ = 1/3, where the ground state is known as a spin-polarized ferromagnetic state, i

Anastasia Volovich

It is shown that a Lagrangian, describing the interaction of the gravitation field with the dilaton and the antisymmetric tensor in arbitrary dimension spacetime, admits an isotropic p-brane solution consisting of three blocks. Relations with known p-brane solutions are discussed. In particular, in ten-dimensional spacetime the three-block p-brane solution i

Glennys R. Farrar, G. T. Gabadadze

We investigate whether known properties of the $η&#39;$ meson are consistent with its being the Goldstone boson of the spontaneously broken anomaly-free R symmetry required in the light gluino scenario. We fit the masses and $2γ$ decays of the $η$ and $η&#39;$ mesons, and also their production in radiative $J/ψ$ decays. We find that the $η-η&#39;$ system is

R. B. Laughlin

I argue that the ``gap&#39;&#39; recently observed at the Brillouin zone face of cuprate superconductors in photoemission by Marshall et al [Phys. Rev. Lett. 76, 4841 (1996)] and Ding et al [Nature 382, 54 (1996)] is evidence for the decay of the injected hole into a spinon-holon pair.

B. Mitrovic, M. Castle

The interlayer pair tunneling model of Anderson et al. is generalized to include the strong coupling effects associated with in-plane interactions. The equations for the superconducting transition temperature T_{c} are solved numerically for several models of electron-optical phonon coupling. The nonmagnetic in-plane impurity scattering suppresses T_{c} in a

T. Mor

Noise causes severe difficulties in implementing quantum computing and quantum cryptography. Several schemes have been suggested to reduce this problem, mainly focusing on quantum computation. Motivated by quantum cryptography, we suggest a coding which uses $N$ quantum bits ($N=n^2$) to encode one quantum bit, and reduces the error exponentially with $n$. O

David Ritz Finkelstein, Heinrich Saller, Zhong Tang

Let a quantum network be a Fermi-Dirac assembly of Fermi-Dirac assemblies of ...of quantum points, interpreted topologically. The simplest quantum-network vacuum modes with exact conservation of relativistic energy-momentum and angular momentum also support the local non-Abelian groups of the standard model, torsion and gravity. The spacetime points of these

David Ritz Finkelstein, Heinrich Saller, Zhong Tang

Seeking a relativistic quantum infrastructure for gauge physics, we analyze spacetime into three levels of quantum aggregation analogous to atoms, bonds and crystals. Quantum spacetime points with no extension make up more complex link units with microscopic extension, which make up networks with macroscopic extension. Such a multilevel quantum theory implie

P. N. Bibikov, P. P. Kulish

Definition of Dirac operators on the quantum group $SU_{q}(2)$ and the quantum sphere $S^{2}_{q μ}$ are discussed. In both cases similar $SU_{q}(2)$-invariant form is obtained. It is connected with corresponding Laplace operators.

R. J. Furnstahl, Brian D. Serot, Hua-Bin Tang

An effective hadronic lagrangian consistent with the symmetries of quantum chromodynamics and intended for applications to finite-density systems is constructed. The degrees of freedom are (valence) nucleons, pions, and the low-lying non-Goldstone bosons, which account for the intermediate-range nucleon-nucleon interactions and conveniently describe the nonv

A. S. Jensen, E. Garrido, D. V. Fedorov

The angular part of the Faddeev equations is solved analytically for s-states for two-body square-well potentials. The results are, still analytically, generalized to arbitrary short-range potentials for both small and large distances. We consider systems with three identical bosons, three non-identical particles and two identical spin-1/2 fermions plus a th

E. Garrido, D. V. Fedorov, A. S. Jensen

Momentum distributions of particles from nuclear break-up of fast three-body halos are calculated for polarized beam and outgoing fragments. These momentum distributions are combined in observable quantities which emphasize the two-body correlations in the initial three-body structure as well as in the final two-body system. Applying the formalism to 11Li we

E. Garrido, D. V. Fedorov, A. S. Jensen

Momentum distributions of particles from nuclear break-up of fast three-body halos are calculated incorporating effects of final state interactions. The same two-body interactions between the particles are used to calculate both the ground state structure and the final state of the reaction processes. The ground state wave function reproduces size and energy

E. Garrido, D. V. Fedorov, A. S. Jensen

We investigate two simple prescriptions to account for the Pauli principle in a three-body cluster model employing a new method based on an adiabatic hyperspherical expansion to solve the Faddeev equations in coordinate space. The resulting wave functions are computed and compared. They are furthermore tested on halo nuclei by calculations of momentum distri

E. Garrido, D. V. Fedorov, A. S. Jensen

Momentum distributions of particles from fast three-body halo fragmentation reactions with polarized beams and outgoing fragments are analyzed by use of the sudden approximation. The final state interaction between the two non-disturbed particles is considered. We first give a general and detailed description of the method. We introduce observable quantities

Saharon Shelah

In this note we answer a question of Kunen (15.13 [Mi91]) showing that it is consistent that there are full Souslin trees

Franz-Viktor Kuhlmann, Salma Kuhlmann, Saharon Shelah

We prove that for no nontrivial ordered abelian group G, the ordered power series field R((G)) admits an exponential, i.e. an isomorphism between its ordered additive group and its ordered multiplicative group of positive elements, but that there is a non-surjective logarithm. For an arbitrary ordered field k, no exponential on k((G)) is compatible, that is,

Adam L. Epstein, Michael Yampolsky

We exhibit products of Mandelbrot sets in the two-dimensional complex parameter space of cubic polynomials. These products were observed by J. Milnor in computer experiments which inspired Lavaurs&#39; proof of non local-connectivity for the cubic connectedness locus. Cubic polynomials in such a product may be renormalized to produce a pair of quadratic maps

Yuri I. Lyubich

A S. N. Bernstein problem is solved under a natural irreducibility condition. Earlier this result was obtained only in some special case.

H. Aratyn, C. Rasinariu

A systematic method of constructing manifestly supersymmetric $1+1$-dimensional KP Lax hierarchies is presented. Closed expressions for the Lax operators in terms of superfield eigenfunctions are obtained. All hierarchy equations being eigenfunction equations are shown to be automatically invariant under the (extended) supersymmetry. The supersymmetric Lax m

W. A. Sabra

The embedding of the isometry group of the coset spaces SU(1,n)/ U(1)xSU(n) in Sp(2n+2,R) is discussed. The knowledge of such embedding provides a tool for the determination of the holomorphic prepotential characterizing the special geometry of these manifolds and necessary in the superconformal tensor calculus of N=2 supergravity. It is demonstrated that th

Azakov S.

The classical and quantum aspects of the Schwinger model on the torus are considered. First we find explicitly all zero modes of the Dirac operator in the topological sectors with nontrivial Chern index and is spectrum. In the second part we determine the regularized effective action and discuss the propagators related to it. Finally we calculate the gauge i

Horacio Alberto Falomir, Ricardo Enrique Gamboa Saravi, Mar\&#39;{\I}a Amelia Muschietti, Eve Mariel Santangelo

A formula relating quotients of determinants of elliptic differential operators sharing their principal symbol, with local boundary conditions, to the corresponding Green function is given.

H. Falomir, R. E. Gamboa Saraví, M. A. Muschietti, E. M. Santangelo

We study functional determinants for Dirac operators on manifolds with boundary. We give, for local boundary conditions, an explicit formula relating these determinants to the corresponding Green functions. We finally apply this result to the case of a bidimensional disk under bag-like conditions.

Kei-Ichi Kondo

Based on the path integral formalism, we rederive and extend the transverse Ward-Takahashi identities (which were first derived by Yasushi Takahashi) for the vector and the axial vector currents and simultaneously discuss the possible anomaly for them. Subsequently, we propose a new scheme for writing down and solving the Schwinger-Dyson equation in which th

Gabriel Lopes Cardoso, Dieter Lust, Thomas Mohaupt

We discuss the transformation properties of classical extremal N=2 black hole solutions in S-T-U like models under S and T duality. Using invariants of (subgroups of) the triality group, which is the symmetry group of the classical BPS mass formula, the transformation properties of the moduli on the event horizon and of the entropy under these transformation

Karl Strobl, Mark Hindmarsh

The idea of biased symmetries to avoid or alleviate cosmological problems caused by the appearance of some topological defects is familiar in the context of domain walls, where the defect statistics lend themselves naturally to a percolation theory description, and for cosmic strings, where the proportion of infinite strings can be varied or disappear entire

Paul Mansfield

Using analyticity of the vacuum wave-functional under complex scalings, the vacuum of a quantum field theory may be reconstructed from a derivative expansion valid for slowly varying fields. This enables the eigenvalue problem for the Hamiltonian to be reduced to algebraic equations. Applied to Yang-Mills theory this expansion leads to a confining force betw

M. Buza, Y. Matiounine, J. Smith, W. L. van Neerven

We present analytic formulae for the heavy flavour coefficient functions for polarized deep inelastic lepton-hadron scattering. The expressions are valid in the kinematical regime $Q^2\gg m^2$ where $Q^2$ and $m^2$ stand for the masses squared of the virtual photon and heavy quark respectively. Using these coefficient functions we have computed the next-to-l

Lev Kofman, Andrei Linde, Alexei Starobinsky

In a recent paper Boyanovsky et al (hep-ph/9608205) studied preheating for a particular theory of the inflaton field. Although they results essentially confirm those of the original papers on reheating after inflation, they claimed that most of the earlier works on preheating did not take into account backreaction of created particles, misused the Mathieu eq

Alexander Kusenko, Paul Langacker

The experimental data, as well as theoretical considerations allow (and, in some cases, require) the Universe at present to rest in a false vacuum, whose approximate stability imposes constraints on the model parameters. Under very general and mild conditions, the Universe would have ended up in the standard vacuum even if the potential has deeper minima, pr

M. Svec

The measurements of reactions $π^- p \to π^- π^+ n$ and $π^+ n \to π^+ π^- p$ on polarized targets at CERN found a strong dependence of pion production amplitudes on nucleon spin. Analyses of recent measurements of $π^- p \to π^0π^0 n$ reaction on unpolarized targets by GAMS Collaboration at 38 GeV/c and BNL E852 Collaboration at 18 GeV/c use the assumption

J. G. Körner

I discuss the structure of current-induced bottom baryon to charm baryon transitions, and the structure of pion and photon transitions between heavy charm or bottom baryons in the Heavy Quark Symmetry (HQS) limit as $m_Q\rightarrow\infty$. By doing a spin-parity analysis I derive a general formula which allows one to enumerate the independent HQS amplitudes

Hideo Suganuma, Hiroko Ichie, Hiroshi Toki, Hideko Monden

The QCD phase transition at finite temperature is studied with the dual Ginzburg-Landau theory, which is the QCD effective theory based on the dual Higgs mechanism by QCD-monopole condensation. At high temperature, the confinement force is largely reduced by thermal effects, which leads to the swelling of hadrons. Simple formulae for the surface tension and

Hideo Suganuma, Shoich Sasaki, Hiroko Ichie, Hiroshi Toki

We study the dual Higgs mechanism for the nonperturbative QCD. We point out two kind of the ``see-saw&#39;&#39; relations between electric and magnetic sectors. Owing to the Dirac condition $eg=4π$, the dual Ginzburg-Landau theory has the asymptotic freedom nature on the gauge coupling constant $e$, where the ``walking coupling constant&#39;&#39; is predicte

Hideo Suganuma, Hiroko Ichie, Hideko Monden, Shoichi Sasaki

The cosmological QCD phase transition is studied in terms of the color confinement at finite temperature using the dual Higgs theory of QCD. The confinement force is largely reduced at high temperature, which leads to the swelling of hadrons. We derive analytical formulae for the surface tension and the boundary thickness of the mixed phase from the effectiv