October 1995 arXiv papers — page 9

P. T. de Zeeuw, C. M. Carollo

Recent work on the construction of spherical, Axisymmetric and triaxial dynamical models for elliptical galaxies is reviewed briefly, including their role in providing evidence for dark halos and central black holes. The different orbital structures and shapes of low-mass and giant elliptical galaxies provide essential constraints on scenarios of galaxy form

M. Cappi, T. Mihara, M. Matsuoka, K. Hayashida

Results from the X-ray spectral analysis of the ASCA PV phase observation of the Seyfert 1 galaxy IC 4329A are presented. We find that the 0.4 - 10 keV spectrum of IC 4329A is best described by the sum of a steep ($Γ\sim 1.98$) power-law spectrum passing through a warm absorber plus a strong reflection component and associated Fe K line, confirming recent re

John Collins

I explain the methods that are used in field theory for problems involving typical momenta on two or more widely disparate scales. The principal topics are: (a) renormalization, which treats the problem of taking an ultra-violet cut-off to infinity, (b) the renormalization group, which is used to relate phenomena on different scales, (c) the operator product

Dong-Sheng Du, Mao-Zhi Yang

We consider the CP violating effect for $B\to X_sl^+l^-$ process, including both short and long distance effects. We obtain the CP asymmetry parameter and present its variation over the dilepton mass.

S. Krivonos, A. Sorin

We review the new approach to the theory of nonlinear $W$-algebras which is developed recently and called {\it conformal linearization}. In this approach $W$-algebras are embedded as subalgebras into some {\it linear conformal} algebras with a finite set of currents and most of their properties could be understood in a much simpler way by studing their linea

Andrzej Herdegen

A C*-algebra of asymptotic fields which properly describes the infrared structure in quantum electrodynamics is proposed. The algebra is generated by the null asymptotic of electromagnetic field and the time asymptotic of charged matter fields which incorporate the corresponding Coulomb fields. As a consequence Gauss' law is satisfied in the algebraic se

J. A. de Azcarraga, F. Rodenas

Using general but simple covariance arguments, we classify the `quantum' Minkowski spaces for dimensionless deformation parameters. This requires a previous analysis of the associated Lorentz groups, which reproduces a previous classification by Woronowicz and Zakrzewski. As a consequence of the unified analysis presented, we give the commutation propert

V. D. Dzhunushaliev

The analogy between the Cooper pair in high temperature superconductor and the quark-antiquark pair in quantum chromodynamics (QCD) is proposed. In QCD the nonlinear chromodynamical field between a quark and an antiquark is confined to a tube. So we assume that there is the strong interaction between phonons which can confine them to some tube too. This tube

Stephan Narison

We present a summary update of the QCD spectral sum rule (QSSR) results for the running and {\it perturbative pole} quark masses, the $f_D$ and $f_B$ leptonic decay constants, the heavy-to-light and heavy-to-heavy exclusive transition-form factors. Analytic expressions of these latter quantities are presented, which give a deeper understanding of their $q^2$

J. Gallego, J. Zamorano, A. Aragon-Salamanca, M. Rego

The Universidad Complutense de Madrid (UCM) Survey is a long-term project aiming at finding and analysing star-forming galaxies detected by their H$α$ emission in Schmidt objective-prism plates. The instrumental set-up limits the volume of the Universe surveyed to a redshift $z\lesssim0.045$. So far we have discovered several hundred emission-line galaxies (

Giampiero Esposito, Hugo A. Morales-Tecotl, Luis O. Pimentel

The quantization of closed cosmologies makes it necessary to study squared Dirac operators on closed intervals and the corresponding quantum amplitudes. This paper proves self-adjointness of these second-order elliptic operators.

J. F. Bell, M. Bailes

We demonstrate how measuring orbital period derivatives can lead to more accurate distance estimates and transverse velocities for some nearby binary pulsars. In many cases this method will estimate distances more accurately than is possible by annual parallax, as the relative error decreases as t^-5/2. Unfortunately, distance uncertainties limit the degree

Kiyoshi Ezawa

A discretized version of canonical quantum gravity proposed by Loll is investigated. After slightly modifying Loll's discretized Hamiltonian constraint, we encode its action on the spin network states in terms of combinatorial topological manipulations of the lattice loops. Using this topological formulation we find new solutions to the discretized Wheel

Jinwu Ye

Yuval-Anderson's scaling analysis and Affleck-Ludwig's Conformal Field Theory approach are applied to the $k$ channel {\em spin anisotropic} Kondo model. Detailed comparisons with the available Emery-Kivelson's Abelian Bosonization approaches are made. It is shown that the EK line exists for any $k$, although it can be mapped to free fermions onl

B. Enriquez, A. Yu. Orlov, V. N. Rubtsov

We recall Krichever's construction of additional flows to Benney's hierarchy, attached to poles at finite distance of the Lax operator. Then we construct a ``dispersionful'' analogue of this hierarchy, in which the role of poles at finite distance is played by Miura fields. We connect this hierarchy with $N$-wave systems, and prove several fa

Ole Steuernagel, John A. Vaccaro

We describe the representation of arbitrary density operators in terms of expectation values of simple projection operators. Two representations are presented which yield non--recursive schemes for experimentally determining the density operator of any quantum system. We suggest a possible experimental implementation in quantum optics.

Matteo G. A. Paris

A high-sensitive interferometric scheme is presented. It is based on homodyne detection and squeezed vacuum phase properties. The resulting phase sensitivity scales as $δϕ\simeq {1/4} \bar{n}^{-1}$ with respect to input photons number.

Marek Czachor

An explicitly covariant formalism for dealing with Bargmann-Wigner fields is developed. An invariance of the Barmann-Wigner norm can be proved in a unified way for both massive and massless fields. It is shown that there exists some freedom in the choice of the form of the Bargmann-Wigner scalar product.

John R. Klauder

Divergences that arise in the quantization of scalar quantum field models by means of a lattice-space functional integration may be attributed to a single integration variable, and this fact is demonstrated by showing that if the integrand for that single integration variable is appropriately changed, then a perturbation expansion becomes order-by-order fini

Tatsuhiro Nakajima, Hiro-Fumi Yamada

Schur's $Q$-functions with reduced variables are discussed by employing a combinatorics of strict partitions. They are called reduced $Q$-functions. We give a description of the linear relations among reduced $Q$-functions.

Teruhisa S. Komatsu, Shin-ichi Sasa

We study pattern selection of cracks in directionally drying fractures by analyzing the experimental systems recently devised by C. Allain and L. Limat. [Phys. Rev. Lett. {\bf 74}, 2981 (1995).] Proposing a simple picture of crack formation, we clarify the mechanism of how cracks array regularly and find that the interval between neighboring cracks is propor

A. De Pace

The parity-violating quasielastic electron scattering response is explored within the context of a model that builds antisymmetrized random phase approximation and Hartree-Fock correlations on a relativistic Fermi gas basis. Particular emphasis is put on the weak-neutral longitudinal response function, since this observable displays a strong sensitivity to i

M. B. Barbaro, A. De Pace, T. W. Donnelly, A. Molinari

The longitudinal quasielastic parity-violating electron scattering response is explored within the context of a model that builds antisymmetrized RPA-HF correlations on a relativistic Fermi gas basis. The large sensitivity to nuclear dynamics of this observable, found in previous studies where only pionic correlations were included, is shown to survive in th

P. F. Mastinu, P. M. Milazzo, M. Bruno, M. D'agostino

A procedure has been developed for the charge, mass and energy calibration of ions produced in nuclear heavy ion reactions. The charge and mass identification are based on a $Δ$E-E technique. A computer code determines the conversion from ADC channels into energy values, atomic number and mass of the detected fragments by comparing with energy loss calculati

Ashok Das, Sudhakar Panda

We show how a general nonstandard Lax equation (supersymmetric or otherwise) can be expressed as a standard Lax equation. This enables us to define the Gelfand-Dikii brackets for a nonstandard supersymmetric equation. We discuss the Hamiltonian structures for the nonstandard super KP system and work out explicitly the two Hamiltonian structures of the supers

S. Ferrara, L. Girardello, M. Porrati

It is shown that the minimal Higgs sector of a generic N=2 supergravity theory with unbroken N=1 supersymmetry must contain a Higgs hypermultiplet and a vector multiplet. When the multiplets parametrize the quaternionic manifold SO(4,1)/SO(4), and the special Kahler manifold SU(1,1)/U(1), respectively, a vanishing vacuum energy with a sliding massive spin 3/

R. Grimm

Some general features of locally supersymmetric theories (N=1 in four dimensions) involving Chern-Simons forms and antisymmetric tensors are sketched out. The relevance of the three-form multiplet both for the description of Chern-Simons forms and the supersymmetry properties of the gaugino condensate is pointed out.

P. Bowcock, E. Corrigan, R. H. Rietdijk

Classical integrability is investigated for affine Toda field theories in the presence of a constant background tensor field. This leads to a further set of discrete possibilities for integrable boundary conditions depending upon the time-derivative of the fields at the boundary but containing no free parameters other than the bulk coupling constant.

Akira Fujii

We consider the soliton solutions in 1- and (1+1)-dimensional Toda lattice models with a boundary. We make use of the solutions already known on a full line by means of the Hirota's method. We explicitly construct the solutions satisfying the boundary conditions. The ${\bf Z}_{\infty}$-symmetric boundary condition can be introduced by the two-soliton sol

Burkhard Kleihaus, Jutta Kunz, Abha Sood

SU(3) Einstein-Yang-Mills-dilaton theory possesses sequences of static spherically symmetric sphaleron and black hole solutions for the SU(2) and the SO(3) embedding. The solutions depend on the dilaton coupling constant $γ$, approaching the corresponding Einstein-Yang-Mills solutions for $γ\rightarrow 0$, and Yang-Mills-dilaton solutions in flat space for $

S. Randjbar--Daemi, J. Strathdee

The vacuum polarization due to chiral fermions on a 4--dimensional Euclidean lattice is calculated according to the overlap prescription. The fermions are coupled to weak and slowly varying background gauge and Higgs fields, and the polarization tensor is given by second order perturbation theory. In this order the overlap constitutes a gauge invariant regul

G. M. Cicuta, S. Stramaglia, A. G. Ushveridze

In this paper the relationship between the problem of constructing the ground state energy for the quantum quartic oscillator and the problem of computing mean eigenvalue of large positively definite random hermitean matrices is established. This relationship enables one to present several more or less closed expressions for the oscillator energy. One of suc

Chris Radford

The full ``classical" Dirac-Maxwell equations are considered under various simplifying assumptions. A reduction of the equations is performed in the case when the Dirac field is {\em static} and a further reduction is performed in the case of {\em spherical symmetry}. These static spherically symmetric equations are examined in some detail and a numerica

J. Hisano, T. Yanagida

We construct an extension of the recently proposed dynamical model for the breaking of SU(5)$_{\rm GUT}$ gauge symmetry, in which a pair of massless chiral supermultiplets for Higgs doublets are naturally obtained. We point out that a model at a specific point in the parameter space of superpotential is regarded as a low-energy effective theory of an N=2 sup

G. Lazarides, Q. Shafi

In the context of supersymmetric models, we analyze the production of topological defects at the end of inflation driven by a conjugate pair of inflaton fields which are non-singlets under the continuous symmetry group of the theory. We find that magnetic monopoles of mass on the order of $10^{13}\ GeV$ can survive inflation and be present in our galaxy at a

Tony M. Liss

I review the prospects for measuring the properties of the top quark at the Tevatron, with an integrated luminosity of 2 fb$^{-1}$ or more, and at LHC in the early running at instantaneous luminosities of $10^{32}-10^{33}~cm^{-2}~s^{-1}$.

M. Gremm, G. Köpp, F. Krüger, L. M. Sehgal

We consider the effects of quark-binding on the angular distribution and polarization characteristics of the inclusive decays $Λ_b \to X_s γ$ and $Λ_b \to X_c l \bar{\n}_l$ $(l=e, τ)$, using the methods of heavy quark effective theory.

M. Bawin, J. Cugnon, H. Sazdjian

Strongly coupled positronium, considered in its pseudoscalar sector, is studied in the framework of relativistic quantum constraint dynamics. Case's method of self-adjoint extension of singular potentials, which avoids explicit introduction of regularization cut-offs, is adopted. It is found that, as the coupling constant αincreases, the bound state spec

Antonio Riotto

We propose a general method to compute $CP$-violating observables from extensions of the standard model in the context of electroweak baryogenesis. It is alternative to the one recently developed by Huet and Nelson and relies on a nonequilibrium quantum field theory approach. The method is valid for all shapes and sizes of the bubble wall expanding in the th

Zenrō Hioki

Two topics on the standard electroweak theory are discussed based on its remarkable success in precision analyses. One is a test of structure of the radiative corrections to the weak-boson masses as a further precision analysis. The other is an indirect Higgs-boson search through the radiative corrections to the various quantities measured at LEP.

Yongseok Oh, Byung-Yoon Park

We obtain the spectra of excited heavy baryons containing one heavy quark by quantizing the exactly-solved heavy meson bound states to Skyrme soliton. The results are comparable to the recent experimental observations and quark model predictions, and are consistent with the heavy quark spin symmetry. However, somewhat large dependence of the results on the h

U. Baur

The current theoretical understanding of anomalous gauge boson couplings is reviewed, and the direct measurement of these couplings in present and future hadron collider experiments is briefly discussed.

Matthias Burkardt

The status of the transverse lattice formulation of light-front QCD is reviewed. It is explained how confinement arises in this formulation for large lattice spacing. The nonperturbative renormalization procedure is outlined in general and a more detailed discussion is given for the case of $QCD_{2+1}(N_C\rightarrow \infty)$.

Dongsheng Du, Libo Guo

Using the next-to-leading order low energy effective Hamiltonian for $|ΔB|=1$, $ΔC=ΔU=0$ transitions, the contributions of electroweak penguin operators in $ B^-(\overline {B_d^0})\rightarrow PP$ and $PV$ decays are estimated in the standard model. We find that, for some channels, the electroweak penguin effects can enhance or reduce the QCD penguin and/or t

Domenico Giulini

We investigate the group of large diffeomorphisms fixing a frame at a point for general closed 3-manifolds. We derive some general structural properties of these groups which relate to the picture of the manifold as being composed of extended `objects' (geons).

Marcelo Alves

We discuss the two-dimensional dilaton gravity with a scalar field as the source matter. The coupling between the gravity and the scalar, massless, field is presented in an unusual form. We work out two examples of these couplings, and solutions with black-hole behaviour are discussed and compared with those found in the literature.

Sonali Mukherjee, Hisao Nakanishi

We study diffusion on a substrate with permanent traps distributed with critical positional correlation, modeled by their placement on the perimeters of a critical percolation cluster. We perform a numerical analysis of the vibrational density of states and the largest eigenvalue of the equivalent scalar elasticity problem using the method of Arnoldi and Saa

P. Fendley, F. Lesage, H. Saleur

We develop a unified theoretical framework for the anisotropic Kondo model and the boundary sine-Gordon model. They are both boundary integrable quantum field theories with a quantum-group spin at the boundary which takes values, respectively, in standard or cyclic representations of the quantum group $SU(2)_q$. This unification is powerful, and allows us to

Jun Zhang, Yung-Eun Sung, P. A. Rikvold, A. Wieckowski

We study the underpotential deposition of Cu on single-crystal Au(111) electrodes in sulfate-containing electrolytes by a combination of computational statistical-mechanics based lattice-gas modeling and experiments. The experimental methods are in situ cyclic voltammetry and coulometry and ex situ Auger electron spectroscopy and low-energy electron diffract

Martin Howard

We study fluctuation effects in a two species reaction-diffusion system, with three competing reactions $A+A\rightarrow\emptyset$, $B+B\rightarrow\emptyset$, and $A+B\rightarrow\emptyset$. Asymptotic density decay rates are calculated for $d\leq 2$ using two separate methods - the Smoluchowski approximation, and also field theoretic/renormalisation group (RG

T. Guhr

The transition from arbitrary to chaotic fluctuation properties in quantum systems is studied in a random matrix model. It is assumed that the Hamiltonian can be written as the sum of an arbitrary and a chaos producing part. The Gaussian ensembles are used to model the chaotic part. A closed integral representation for all correlations in the case of broken

N. B. Wilding, P. Nielaba

Monte Carlo simulations are used to investigate the tricritical point properties of a 2d spin fluid. Measurements of the scaling operator distributions are employed in conjunction with a finite-size scaling analysis to locate the tricritical point and determine the directions of the relevant scaling fields and their associated tricritical exponents. The scal

N. C. Pesheva, J. G. Brankov, E. Canessa

A layer-by-layer description of the asymmetric lattice gas model for 1/f-noise suggested by Jensen [Phys. Rev. Lett. 64, 3103 (1990)] is presented. The power spectra of the lattice layers in the direction perpendicular to the particle flux is studied in order to understand how the white noise at the input boundary evolves, on the average, into 1/f-noise for

Nobuyuki Katoh, Masatoshi Imada

We investigate the mechanism of spin gap formation in a two-dimensional model relevant to Mott insulators such as CaV$_4$O$_9$. From the perturbation expansion and quantum Monte Carlo calculations, the origin of the spin gap is ascribed to the four-site plaquette singlet in contrast to the dimer gap established in the generalized dimerized Heisenberg model.

Sang-Yoon Kim, Kijin Lee

We study bifurcations associated with stability of the lowest stationary point (SP) of a damped parametrically forced pendulum by varying $ω_0$ (the natural frequency of the pendulum) and $A$ (the amplitude of the external driving force). As $A$ is increased, the SP will restabilize after its instability, destabilize again, and so {\it ad infinitum} for any

Satoru Morita

We propose a new method to investigate collective behavior in a network of globally coupled chaotic elements generated by a tent map. In the limit of large system size, the dynamics is described with the nonlinear Frobenius-Perron equation. This equation can be transformed into a simple form by making use of the piecewise linear nature of the individual map.

M. cappi, T. Mihara, M. Matsuoka, W. Brinkmann

The first X-ray observation of the Seyfert 2 galaxy NGC5252 is reported. ASCA collected $\sim 4000$ photons/detector enough to perform an accurate spectral analysis of this source. The luminosity of NGC5252 is L$_{\rm X}$(0.7-10 keV) $\simeq 2.6 \times 10^{43}$ erg s$^{-1}$, typical of a Seyfert 1 galaxy. A simple description of the spectrum with a single po

S. Mollerach, E. Roulet

We analyse the effects on the predictions for the microlensing searches toward the Galactic bulge coming from the fact that not all the stars monitored belong to the bulge itself, but that a non--negligible fraction of them actually are in the Galactic disk. The different distribution and motions of these disk stars make their associated microlensing rates a

Zsolt Frei, Puragra Guhathakurta, James E. Gunn, J. Anthony Tyson

We present a digital catalog of images of 113 galaxies in this paper. These galaxies are all nearby, bright, large and well resolved. All images were recorded with charge coupled devices (CCDs) at the Palomar Observatory with the 1.5 meter telescope and at the Lowell Observatory with the 1.1 meter telescope. At Palomar we used the Thuan--Gunn g, r and i phot

J. J. Hope, C. M. Savage

The energy spectrum for a system of atoms in a periodic potential can exhibit a gap in the band structure. We describe a system in which a laser is used to produce a mechanical potential for the atoms, and a standing wave light field is used to shift the atomic levels using the Autler-Townes effect, which produces a periodic potential. The band structure for

H. -T. S. Lihn, S. Wu, S. Kaplan, H. D. Drew

We report measurements of the far infrared transmission of superconducting YBa$_2$Cu$_3$O$_{7-δ}$ thin films from 5 cm$^{-1}$ to 200 cm$^{-1}$ in fields up to 14$T$. A Kramers-Kronig analysis of the magneto-transmission spectrum yields the magneto-conductivity tensor. The result shows that the magneto-conductivity of YBa$_2$Cu$_3$O$_{7-δ}$ is dominated by th

John C. Tsai, David A. Buote

We analyze with hydrodynamical simulations the evolution of galaxy clusters in a cosmological environment. Power ratios (Buote \& Tsai 1995) are used to quantitatively relate cluster morphologies to their dynamical states. The simulated clusters follow the same ``evolutionary track&#39;&#39; obeyed by a sample of low-redshift $(z<0.2)$ ROSAT PSPC clusters (B

Alex Madon, Thomas Klinger

Experimental data from an experiment on drift--waves in plasma is presented. The experiment provides a space--time diagnostic and has a control parameter that permits the study of the transition from a stable plasma to a turbulent plasma. The biorthogonal decomposition is used to analyse the data. We introduce the notion of complex modulation for two--dimens

Thomas Buchert, Juergen Ehlers

Idealizing matter as a pressureless fluid and representing its motion by a peculiar--velocity field superimposed on a homogeneous and isotropic Hubble expansion, we apply (Lagrangian) spatial averaging on an arbitrary domain $\cal D$ to the (nonlinear) equations of Newtonian cosmology and derive an exact, general equation for the evolution of the (domain dep

J. O. Madsen, E. Ragoucy

In a recent paper, the authors have shown that the secondary reduction of W-algebras provides a natural framework for the linearization of W-algebras. In particular, it allows in a very simple way the calculation of the linear algebra $W(G,H)_{\geq0}$ associated to a wide class of W(G,H) algebras, as well as the expression of the W generators of W(G,H) in te

Claes R Cramer

We simplify the warp drive space-time so that it becomes stationary and the distorsion becomes one-dimensional and static. We use this simplified warp drive space-time as a background for a photon field. We shall especially use the Drummond\&Hathrell action in order to investigate the velocity effects on photons in this background. Finally, we discuss the li

Tilo Wettig, A. Schäfer, H. A. Weidenmüller

The chiral phase transition of QCD is analyzed in a model combining random matrix elements of the Dirac operator with specially chosen non-random ones. The special form of the latter is motivated by the assumption that the fermionic quasi-zero modes associated with instanton and anti-instanton configurations determine the chiral properties of QCD. Our result

R. Beig, Piotr T. Chrusciel

We study Killing vector fields in asymptotically flat space-times. We prove the following result, implicitly assumed in the uniqueness theory of stationary black holes. If the conditions of the rigidity part of the positive energy theorem are met, then in such space-times there are no asymptotically null Killing vector fields except if the initial data set c

Ralph Blumenhagen, Rolf Schimmrigk, Andreas Wisskirchen

We identify the exactly solvable theory of the conformal fixed point of (0,2) Calabi-Yau sigma-models and their Landau-Ginzburg phases. To this end we consider a number of (0,2) models constructed from a particular (2,2) exactly solvable theory via the method of simple currents. In order to establish the relation between exactly solvable (0,2) vacua of the h

David M. Kaplan, Jeremy Michelson

There exist extremal p-brane solutions of $D\!=\!11$ supergravity for p=2~and~5. In this paper we investigate the zero modes of the membrane and the five-brane solutions as a first step toward understanding the full quantum theory of these objects. It is found that both solutions possess the correct number of normalizable zero modes dictated by supersymmetry

P. Nattermann, R. Zhdanov

We suggest a method for integrating sub-families of a family of nonlinear {\sc Schrödinger} equations proposed by {\sc H.-D.~Doebner} and {\sc G.A.~Goldin} in the 1+1 dimensional case which have exceptional {\sc Lie} symmetries. Since the method of integration involves non-local transformations of dependent and independent variables, general solutions obtain

Patrick Suppes, Adonai S. Sant&#39;Anna, J. Acacio de Barros

In previous works Suppes and de Barros used a pure particle model to derive interference effects, where individual photons have well-defined trajectories, and hence no wave properties. In the present paper we extend that description to account for the Casimir effect. We consider that the linear momentum $\sum\frac{1}{2}\hbar {\bf k}$ of the vacuum state in q

Herman Feshbach

(transcript of a talk given by Prof.~Feshbach:) Nuclear physics has been and will be a major factor in science and technology. It makes unique and important contributions to medicine, to industry and to other sciences. Interaction with other physics has been strong. Astrophysics and mesoscopic physics are notable examples. But what I shall talk about today a

J. M. Isidro, J. P. Nunes, H. J. Schnitzer

It is known that the partition function and correlators of the two-dimensional topological field theory $G_K(N)/ G_K(N)$ on the Riemann surface $Σ_{g,s}$ is given by Verlinde numbers, dim($V_{g,s,K}$) and that the large $K$ limit of dim($V_{g,s,K}$) gives Vol(${\cal M}_s$), the volume of the moduli space of flat connections of gauge group $G(N)$ on $Σ_{g,s}$

O. J. P. Eboli, H. C. Reis

We study the $λϕ^4$ field theory in a flat Robertson-Walker space-time using the functional Schödinger picture. We introduce a simple Gaussian approximation to analyze the time evolution of pure states and we establish the renormalizability of the approximation. We also show that the energy-momentum tensor in this approximation is finite once we consider the

B. Rosenstein, A. D. Speliotopoulos

Motivated by the weak-strong coupling expansion \cite{Rosenstein}, we calculate the spectrum of hadrons using a systematic $1/d$ ($d$ - dimensionality of spacetime) in addition to a strong coupling expansion in $β$. The $1/d$ expansion is pushed to the next to leading order in ($1/d$) for mesons and next to next to leading order for baryons. We do the calcul

Max Welling

In this paper we consider 2+1-dimensional gravity coupled to N point-particles. We introduce a gauge in which the $z$- and $\bar{z}$-components of the dreibein field become holomorphic and anti-holomorphic respectively. As a result we can restrict ourselves to the complex plane. Next we show that solving the dreibein-field: $e^a_z(z)$ is equivalent to solvin

J. L. Petersen, J. Rasmussen, M. Yu

A review is presented of the recently obtained expressions for conformal blocks for {\it admissible} representations in $SL(2)$ current algebra based on the Wakimoto free field construction. In this realization one needs to introduce a second screening charge, one which depends on fractional powers of free fields. The techniques necessary to deal with these

I. J. R. Aitchison, N. E. Mavromatos

We argue that the gauge-fermion interaction in multiflavour quantum electrodynamics in $(2 + 1)$-dimensions is responsible for non-fermi liquid behaviour in the infrared, in the sense of leading to the existence of a non-trivial (quasi) fixed point that lies between the trivial fixed point (at infinite momenta) and the region where dynamical symmetry breakin

G. M. Cicuta, A. G. Ushveridze

There exists an exact relationship between the quasi-exactly solvable problems of quantum mechanics and models of square and rectangular random complex matrices. This relationship enables one to reduce the problem of constructing topological ($1/N$) expansions in random matrix models to the problem of constructing semiclassical expansions for observables in

Thomas Hambye

Considering the standard model as an effective electroweak theory, in which we have no scalar mass term in the Higgs potential $(μ^2=0)$, we show that the spontaneous symmetry breaking of $SU(2)_L \times U(1)$ can be induced by top loops. The Higgs boson mass obtained is smaller than 300 GeV.

John Collins

Handedness and a left-right asymmetry have been proposed as methods of probing the polarization of hard jets. If the analyzing powers for these observables are substantial they would provide useful tools for probing polarized hard scattering. This paper proposes that comparing these to the corresponding quantities in beam jets in polarized hadron-hadron coll

D. de Florian, C. A. Garcia Canal, R. Sassot

We calculate and analize the ${\cal{O}}(α_s)$ one-particle inclusive cross section in polarized deep inelastic lepton-hadron scattering, using dimensional regularization and the HVBM prescription for $γ_5$. We discuss the factorization of all the collinear singularities related to the process, particularly those which are absorbed in the redefinition of the

Paul H. Frampton

The CP violation parameter $Re(ε&#39;/ε)$ has previously been calculated in the standard model and the result depends on the top quark mass in an exciting way. We consider how the result is modified in two specific extensions of the standard model. The first adds only fermions, an extra vector-like quark doublet, and tends to reduce $Re(ε&#39;/ε)$. The secon

Paul H. Frampton

After a brief introduction to what are the basic flavor questions to be addressed, I introduce the underlying ideas of horizontal symmetries, with group $G_H$. For the purposes of specific model building, it is useful to classify models according to the scale at which $G_H$ is broken. I consider the three cases: below $m_t$; somewhat above $m_t$; and at $M_{

C. Bourrely, P. Chiappetta, T. Lemaire

We present a new expression of the scattering amplitude, valid for spherical absorbing objects, which leads to an improved version of the eikonal method outside the diffraction region. Limitations of this method are discussed and numerical results are presented and compared successfully with the Mie theory.

Nils A. Tornqvist

A summary of two conferences on the hadron and gluonium spectrum is given, with personal comments on the status of the best candidates for gluonium or non-qq states, such as f0(1370), f0(1500), fJ(1720), fJ(2230), eta(1410), eta(1460), and f1(1420).

Frank Cuypers

We analyze the pair-production of top quarks in polarized $e^+e^-$ scattering in the presence of electroweak dipole moments. For this, we consider two $CP$-odd observables which probe both the real and the imaginary parts of these moments. Polarizing the electron beam turns out to be a main asset.

M. Caselle, F. Gliozzi, U. Magnea, S. Vinti

In the confining phase of any gauge system the mean squared width of the colour flux tube joining a pair of quarks should grow logarithmically as a function of their distance, according to the effective string description of its infrared properties. New data on 3D Z_2 gauge theory, combined with high precision data on the interface physics of the 3D Ising mo

James E. Lidsey

It is shown that spatially flat, isotropic cosmologies derived from the Brans--Dicke gravity action exhibit a scale factor duality invariance. This classical duality is then associated with a hidden $N=2$ supersymmetry at the quantum level and the supersymmetric quantum constraints are solved exactly. These symmetries also apply to a dimensionally reduced ve

Valter Moretti

The Hessling improvement of the Haag, Narnhofer and Stein principle is analysed in the case of a massless scalar field propagating outside of an extremal R-N black hole. It is found that this sort of ``Quantum (Einstein&#39;s) Equivalence Principle&#39;&#39; selects only the R-N vacuum as a physically sensible state, i.e., it selects the temperature $T=0$ on

A. D. Speliotopoulos

Motivated by Haldane&#39;s exclusion statistics, we construct creation and annihilation operators for $g$-ons using a bosonic algebra. We find that $g$-ons appear due to the breaking of a descrete symmetry of the original bosonic system. This symmetry is intimately related to the braid group and we demonstrate a link between exclusion statistics and fraction

Ben Yu-Kuang Hu, Karsten Flensberg

We describe a method for numerically incorporating electron--electron scattering in quantum wells for small deviations of the distribution function from equilibrium, within the framework of the Boltzmann equation. For a given temperature $T$ and density $n$, a symmetric matrix needs to be evaluated only once, and henceforth it can be used to describe electro

Giovanni Vignale, A. H. MacDonald

We investigate transresistance effects in electron-hole double layer systems with an excitonic condensate. Our theory is based on the use of a minimum dissipation premise to fix the current carried by the condensate. We find that the drag resistance jumps discontinuously at the condensation temperature and diverges as the temperature approaches zero.

D. S. Salopek

Recent advances in observational cosmology are changing the way we view the nature of time. In general relativity, the freedom in choosing a time hypersurface has hampered the implementation of the theory. Fortunately, Hamilton-Jacobi theory enables one to describe all time hypersurfaces on an equal footing. Using an expansion in powers of the spatial curvat

August E. Evrard, Christopher A. Metzler, Julio F. Navarro

We use cosmological gas dynamic simulations to investigate the accuracy of galaxy cluster mass estimates based on X-ray observations. The experiments follow the formation of clusters in different cosmological models and include the effects of gravity, pressure gradients, and hydrodynamical shocks. A subset of our ensemble also allows for feedback of mass and

Robert Rutledge, Lam Hui, Walter H. G. Lewin

The observed 2B BATSE distribution is consistent with the faintest GRBs in our sample originating from a redshift of Zmax ~ 0.8-3.0 (90\%), with the most likely values in the range of 1.0-2.2, and is largely insensitive to Omega for models with no evolution. To constrain the model parameter Omega to the range 0.1-1.0 using only Log N -- Log P distributions,

J. Michael Shull, John T. Stocke, Steve Penton

We provide new post-COSTAR data on one sightline (Mrk 421) and updated data from another (I Zw 1) from our Hubble Space Telescope (HST) survey of intergalactic Lyman-alpha clouds located along sightlines to four bright quasars passing through well-mapped galaxy voids (16,000 km/s pathlength) and superclusters (18,000 km/s). We report two more definite detect

Andrew E. Chubykalo, Roman Smirnov-Rueda

The inadequacy of Liénard-Wiechert potentials is demonstrated as one of the examples related to the inconsistency of the conventional classical electrodynamics. The insufficiency of the Faraday-Maxwell concept to describe the whole electromagnetic phenomena and the incompleteness of a set of solutions of Maxwell equations are discussed and mathematically pro

Davide Fioravanti, Francesco Ravanini, Marian Stanishkov

We propose an alternative description of 2 dimensional Conformal Field Theory in terms of Quantum Inverse Scattering. It is based on the generalized KdV systems attached to $A_2^{(2)}$, yielding the classical limit of Virasoro as Poisson bracket structure. The corresponding T-system is shown to coincide with the one recently proposed by Kuniba and Suzuki. We