March 2000 arXiv papers — page 24

Dmitry V. Skryabin

Correspondence between frequency and energy spectra and biorthogonality conditions for the excitations of Bose-Einstein condensates described by Gross-Pitaevskii model have been derived selfconsistently revealing several novel aspects originating in nonselfadjoitness of the Bogoliubov operator. It has been demonstrated that frequency resonances of the excita

Urs Achim Wiedemann

We derive the non-abelian generalization of the Furry approximation which describes the transverse dynamical evolution of a hard projectile parton inside a spatially extended colour target field. This provides a unified starting point for the target rest frame description of the nuclear dependence of a large class of observables. For the case of the virtual

G. Filippov

An extended coherent state for describing a system of two interacting quanum objects is considered. A modified perturbation theory based on using the extended coherent states is formulated.

T. Opatrny, G. Kurizki

We examine several proposed schemes by Franson et al. for quantum logic gates based on non-local exchange interactions between two photons in a medium. In these schemes the presence of a {\em single} photon in a given mode is supposed to induce a large phase shift on another photon propagating in the same medium. We conclude that the schemes proposed so far

Sándor J. Kovács

The article has two parts. The first part is devoted to proving a singular version of the logarithmic Kodaira-Akizuki-Nakano vanishing theorem of Esnault and Viehweg. This is then used to prove other vanishing theorems. In the second part these vanishing theorems are used to prove an Arakelov-Parshin type boundedness result for families of canonically polari

Shi-Liang Zhu, Z. D. Wang

We generalize Yang's theory from the U(1) gauge field to the non-Abelian $U(1)\times SU(2)_{spin}$ gauge field. Based on this generalization and taking into account the geometric Pancharatnam phase as well as an effective Aharonov-Bohm (AB) phase in nonadiabatic noncyclic transport, we calculate the ensemble average Fourier spectrum of the conductance in

Hiranmaya Mishra, Jitendra C. Parikh

We discuss in this note simultaneous existence of chiral symmetry breaking and color superconductivity at finite temperature and density in a Nambu-Jona-Lasinio type model. The methodology involves an explicit construction of a variational ground state and minimisation of the thermodynamic potential. There exists solutions to the gap equations at finite dens

Motomu Tsuda, Takeshi Shirafuji

We reconstruct the Ashtekar's canonical formulation of N = 2 supergravity (SUGRA) starting from the N = 2 chiral Lagrangian derived by closely following the method employed in the usual SUGRA. In order to get the full graded algebra of the Gauss, U(1) gauge and right-handed supersymmetry (SUSY) constraints, we extend the internal, global O(2) invariance

L. Polley

Schroedinger's equation with scalar and vector potentials is shown to describe "nothing but" hopping of a quantum particle on a lattice; any spatial variation of the hopping amplitudes acts like an external electric and/or magnetic field. The main point of the argument is the superposition principle for state vectors; Lagrangians, path integrals,

G. Brida, M. Genovese, C. Novero, E. Predazzi

We report on the first realisation of a test of Bell inequalities using non-maximally entangled states. It is based on the superposition of type I parametric down conversion produced in two different non-linear crystals pumped by the same laser, but with different polarisations. We discuss the advantages and the possible developments of this configuration.

Paul I. Palmer, J. J. Barnett, J. R. Eyre, S. B. Healy

An optimal estimation inverse method is presented which can be used to retrieve simultaneously vertical profiles of temperature and specific humidity, in addition to surface pressure, from satellite-to-satellite radio occultation observations of the Earth's atmosphere. The method is a non-linear, maximum {\it a posteriori} technique which can accommodate

R. Bijker, F. Iachello

We propose a description of cluster states in nuclei in terms of representations of unitary algebras U(n+1), where n is the number of space degrees of freedom. Within this framework, a variety of situations including both vibrational and rotational spectra, soft and rigid configurations, identical and non-identical constituents can be described. As an exampl

Hitoshi Murakami, Tomotada Ohtsuki

We define a filtration on the vector space spanned by Seifert matrices of knots related to Vassiliev's filtration on the space of knots. Further we show that the invariants of knots derived from the filtration can be expressed by coefficients of the Alexander polynomial.

Tom Graber, Ravi Vakil

Ekedahl, Lando, Shapiro, and Vainshtein announced a remarkable formula expressing Hurwitz numbers (counting covers of the projective line with specified simple branch points, and specified branching over one other point) in terms of Hodge integrals. We give a proof of this formula using virtual localization on the moduli space of stable maps, and describe ho

Itay Neeman, Jindrich Zapletal

We present two ways in which the model $L({\mathbb R})$ is canonical assuming the existence of large cardinals. We show that the theory of this model, with {\em ordinal} parameters, cannot be changed by small forcing; we show further that a set of ordinals in $V$ cannot be added to $L({\mathbb R})$ by small forcing. The large cardinal needed corresponds to t

G. Papadopoulos

The investigation of strings and M-theory involves the understanding of various BPS solitons which in a certain approximation can be thought of as solutions of ten- and eleven-dimensional supergravity theories. These solitons have a brane or a intersecting brane interpretation, saturate a bound and are associated with parallel spinors with respect to a conne

Alberto S. Cattaneo, Giovanni Felder

We consider the Poisson sigma model associated to a Poisson manifold. The perturbative quantization of this model yields the Kontsevich star product formula. We study here the classical model in the Hamiltonian formalism. The phase space is the space of leaves of a Hamiltonian foliation and has a natural groupoid structure. If it is a manifold then it is a s

J. Ginibre, G. Velo

We study the theory of scattering for a class of Hartree type equations with long range interactions in arbitrary space dimension n > or = 1, including the case of Hartree equations with time dependent potential V(t,x) = kappa t^(mu - gamma) |x|^{- mu} with 0 < gamma < or =1 and 0 < mu < n.This includes the case of potential V(x) = kappa |x|^(-gamma) and can

Kouki Taniyama, Akira Yasuhara

In 1993 K. Habiro defined $C_k$-move of oriented links and around 1994 he proved that two oriented knots are transformed into each other by $C_k$-moves if and only if they have the same Vassiliev invariants of order $\leq k-1$. In this paper we define Vassiliev invariant of type $(k_1,...,k_l)$, and show that, for $k=k_1+...+k_l$, two oriented knots are tran

Manuel González, Joaquín M. Gutiérrez

We introduce the class of Orlicz-Pettis polynomials between Banach spaces, defined by their action on weakly unconditionally Cauchy series. We give a number of equivalent definitions, examples and counterexamples which highlight the differences between these polynomials and the corresponding linear operators.

David De Wit

Gauß cubature (multidimensional numerical integration) rules are the natural generalisation of the 1D Gauß rules. They are optimal in the sense that they exactly integrate polynomials of as high a degree as possible for a particular number of points (function evaluations). For smooth integrands, they are accurate, computationally efficient formulae. The cons

Martin Schaden

The local covariant continuum action of an SU(2) gauge theory in covariant Abelian gauges is investigated. It describes the critical limit of an Abelian Lattice Gauge Theory (LGT) with an equivariant BRST-symmetry. This Abelian LGT has previously been proven to be physically equivalent to the SU(2)-LGT. Renormalizability requires a quartic ghost interaction

D. G. G. Sasaki S. P. Sorella V. E. R. Lemes

The existence of the vector supersymmetry is analysed within the context of the finite temperature Chern-Simons theory.

G. Bandelloni, S. Lazzarini

In a symplectic framework, the infinitesimal action of symplectomorphisms together with suitable reparametrizations of the two dimensional complex base space generate some type of W-algebras. It turns out that complex structures parametrized by Beltrami differentials play an important role in this context. The construction parallels very closely two dimensio

S. Penati, A. Santambrogio, D. Zanon

We discuss recent results on two-point functions of chiral primary operators in {\cal N}=4 SU(N) supersymmetric Yang-Mills theory. Our results give further support to the belief that such correlators are not renormalized to all orders in g and to all orders in N.

L. Andrianopoli, M. Derix, G. W. Gibbons, C. Herdeiro

We show how non-near horizon, non-dilatonic $p$-brane theories can be obtained from two embedding constraints in a flat higher dimensional space with 2 time directions. In particular this includes the construction of D3 branes from a flat 12-dimensional action, and M2 and M5 branes from 13 dimensions. The worldvolume actions are found in terms of fields defi

M. Frau, L. Gallot, A. Lerda, P. Strigazzi

We review the boundary state description of the non-BPS D-branes in the type I string theory and show that the only stable configurations are the D-particle and the D-instanton. We also compute the gauge and gravitational interactions of the non-BPS D-particles and compare them with the interactions of the dual non-BPS particles of the heterotic string findi

Emili Bagan, Martin Lavelle, David McMullan

Descriptions of the ground state in unbroken gauge theories with charged particles are discussed. In particular it is shown that the on-shell Green&#39;s functions and S-matrix elements corresponding to the scattering of these variables in QED are free of soft and phase infra red divergences and that these variables may be multiplicatively renormalised.

Csaba Csaki, Joshua Erlich, Timothy J. Hollowood

We derive the graviton propagator on the brane for theories with quasi-localized gravity. In these models the ordinary 4D graviton is replaced by a resonance in the spectrum of massive Kaluza-Klein modes, which can decay into the extra dimension. We find that the effects of the extra polarization in the massive graviton propagator is exactly cancelled by the

K. A. Milton, I. L. Solovtsov, O. P. Solovtsova

We consider the Adler $D$-function, which is defined in the spacelike region, and the $e^+e^-$ annihilation ratio smeared, according to the Poggio, Quinn, and Weinberg method, which is determined for timelike argument. We show that the method of the nonperturbative $a$-expansion allows one to describe these Euclidean and Minkowskian characteristics of the pr

K. A. Milton, I. L. Solovtsov, O. P. Solovtsova, V. I. Yasnov

We apply an analytic description to the inclusive decay of the $τ$ lepton. We argue that this method gives not only a self-consistent description of the process both in the timelike region by using the initial expression for $R_τ$ and in the spacelike domain by using the analytic properties of the hadronic correlator, but also leads to the fact that theoreti

G. X. Peng, H. C. Chiang, P. Z. Ning

Because of the mass density-dependence, an extra term should be added to the expression of pressure. However, it should not appear in that of energy according to both the general ensemble theory and basic thermodynamic principle. We give a detail derivation of the thermodynamics with density-dependent particle masses. With our recently determined quark mass

Alexey A. Petrov

I give a brief overview of the physics potential of short baseline experiments at neutrino factories, i.e. facilities providing high energy and high intensity neutrino beams, like the one planned to be built in connection with the proposed high energy muon storage ring. These facilities would offer a unique opportunity to perform new precision studies of QCD

S. Slabospitsky, G. Azuelos

Multiscale technicolor models predict the existence of high mass resonances at hadron colliders. Although the quark fusion process of production dominates, vector boson fusion offers the advantage of allowing forward jet tagging for background suppression. We calculate here the cross section and differential distributions for $ρ_T$ production in the vector b

S. Neumeier, M. Kirchbach

We consider neutral pseudoscalar, $η$, and axial vector, $f_1(1420)$, mesons in the OZI-rule-respecting flavor basis, $\lbrace (\bar s s), {1\over \sqrt{2}}(\bar u u + \bar d d)\rbrace$, and suggest a scenario for their coupling to the nucleon. Within this framework, the non--strange parts of the $ηN$ and f$_1 N$ couplings are modeled by means of triangular

S. Heinemeyer, W. Hollik, G. Weiglein

In the Minimal Supersymmetric Standard Model (MSSM) we incorporate the Higgs-boson propagator corrections, evaluated up to two-loop order, into the prediction of $Γ$(h -> ff) and BR(h -> ff) for f = b, c, $τ$. The propagator corrections consist of the full one-loop contribution, including the effects of non-vanishing external momentum, and corrections of O(a

Patrick B. Greene, Lev Kofman

In inflationary cosmology, the particles constituting the Universe are created after inflation due to their interaction with moving inflaton field(s) in the process of preheating. In the fermionic sector, the leading channel is out-of equilibrium particle production in the non-perturbative regime of parametric excitation, which respects Pauli blocking but di

P. Bialas, A. Morel, B. Petersson, K. Petrov

We investigate the three-dimensional SU(3) gauge theory at finite temperature in the framework of dimensional reduction. The large scale properties of this theory are expected to be conceptually more complicated than in four dimensions. The dimensionally reduced action is computed in closed analytical form. The resulting effective two-dimensional theory is s

T. Affolder

We use 106 $\ipb$ of data collected with the Collider Detector at Fermilab to search for narrow-width, vector particles decaying to a top and an anti-top quark. Model independent upper limits on the cross section for narrow, vector resonances decaying to $\ttbar$ are presented. At the 95% confidence level, we exclude the existence of a leptophobic $\zpr$ bos

P. S. Wesson, H. Liu, S. S. Seahra

We give an exact solution of the five-dimensional field equations which describes a shock wave moving in time and the extra (Kaluza-Klein) coordinate. The matter in four-dimensional spacetime is a cosmology with good physical properties. The solution suggests to us that the 4D big bang was a 5D shock wave.

M. Tajmar, C. de Matos

Using the weak field approximation, we can express the theory of general relativity in a Maxwell-type structure comparable to electromagnetism. We find that every electromagnetic field is coupled to a gravitoelectric and gravitomagnetic field. Acknowledging the fact that both fields originate from the same source, the particle, we can express the magnetic an

W. Kinzel, R. Metzler, I. Kanter

The dynamics of interacting perceptrons is solved analytically. For a directed flow of information the system runs into a state which has a higher symmetry than the topology of the model. A symmetry breaking phase transition is found with increasing learning rate. In addition it is shown that a system of interacting perceptrons which is trained on the histor

A. J. Williamson, L. W. Wang, Alex Zunger

We adopt an atomistic pseudopotential description of the electronic structure of self-assembled, lens shaped InAs quantum dots within the ``linear combination of bulk bands&#39;&#39; method. We present a detailed comparison with experiment, including quantites such as the single particle electron and hole energy level spacings, the excitonic band gap, the el

O. G. Balev, F. T. Vasko, Flavio Aristone, Nelson Studart

Electron transport in nonideal quantum wells (QW) with large-scale variations of energy levels is studied when two subbands are occupied. Although the mean fluctuations of these two levels are screened by the in-plane redistribution of electrons, the energies of both levels remain nonuniform over the plane. The effect of random inhomogeneities on the classic

T. Nattermann, S. Scheidl

A review is given on the theory of vortex-glass phases in impure type-II superconductors in an external field. We begin with a brief discussion of the effects of thermal fluctuations on the spontaneously broken U(1) and translation symmetries, on the global phase diagram and on the critical behaviour. Introducing disorder we restrict ourselves to the experim

W. Kinzel, R. Metzler, I. Kanter

Several scenarios of interacting neural networks which are trained either in an identical or in a competitive way are solved analytically. In the case of identical training each perceptron receives the output of its neighbour. The symmetry of the stationary state as well as the sensitivity to the used training algorithm are investigated. Two competitive perc

F. Alberici-Kious, J_P Bouchaud, L. F. Cugliandolo, P. Doussineau

We present new experimental results on the dielectric constant in orientational glasses K$_{1-x}$Li$_x$TaO$_3$ (KLT) with x < 0.05, together with the detailed (analytic and numerical) study of a model which attributes the observed aging to the motion of the wall of polarization domains. We show that the dielectric constant after positive temperature jumps go

M. Bauer, O. Golinelli

We study the height of the delta peak at 0 in the spectrum of random tree incidence matrices. We show that the average fraction of the spectrum occupied by the eigenvalue 0 in a large random tree is asymptotic to 2x-1 = 0.1342865808195677459999... where x is the unique real root of x = exp(-x). For finite trees, we give a closed form, a generating function,

Joshua L. Cohn

We discuss heat transport in hole-doped manganites, nickelates and cuprates for which real-space charge ordering has been observed. We survey the thermal transport response to charge order in the various materials and the associated structural modifications, particularly distortions of the metal-oxygen polyhedra associated with localized charge, that may be

Masatoshi Sato, Mahito Kohmoto

The unique Fermi surfaces and their nesting properties of Sr2RuO4 are considered. The existence of unconventional superconductivity is shown microscopically, for the first time, from the magnetic interactions (due to nesting) and the phonon-mediated interactions. The odd-parity superconductivity is favored in the $α$ and $β$ sheets of the Fermi surface, and

A. V. Goltsev, G. Bruls

For describing the first-order isostructural valence phase transition in mixed valence compounds we develop a new approach based on the lattice Anderson model. We take into account the Coulomb interaction between localized f and conduction band electrons and two mechanisms of electron-lattice coupling. One is related to the volume dependence of the hybridiza

Benny Davidovich, Itamar Procaccia

Diffusion Limited Aggregation (DLA) is a model of fractal growth that was introduced in 1981 and had since attained a paradigmatic status due to its simplicity and its underlying role for a variety of pattern forming processes. Despite tremendous efforts there is no theory to compute the fractal dimension of DLA from first principles. In this Letter we offer

Xiao-Gang Wang, Anne Chaka, Matthias Scheffler

We report that calculating the Gibbs free energy of the alpha-Al_2O_3 (0001) surfaces in equilibrium with a realistic environment containing both oxygen and hydrogen species is essential for obtaining theoretical predictions consistent with experimental observations. Using density-functional theory we find that even under conditions of high oxygen partial pr

Avinash Singh

It is shown that for the spin 1/2 anisotropic Heisenberg model the result for the transition temperature is completely insensitive to the anisotropy within the Onsager reaction field theory, which yields a vanishing T_c in two dimensions, in total conflict with the expected finite T_c, increasing with anisotropy. This establishes that the breakdown of the On

Leon Balents, Reinhold Egger

We present a general formulation of spin-dependent transport through a clean one-dimensional interacting quantum wire or carbon nanotube, connected to non-collinear ferromagnets via tunnel junctions. We show that the low energy description of each junction is given by a conformally-invariant boundary condition representing *exchange coupling*, in addition to

Steven R. White, Rajiv R. P. Singh

Density matrix renormalization group (DMRG) calculations on large systems (up to 3096 spins) indicate that the ground state of the Heisenberg model on a 3-chain Kagome strip is spontaneously dimerized. This system has degenerate ground states and a gap to triplet and singlet excitations. These results are in direct contradiction with recent results of Azaria

Ashvin Vishwanath, David Carpentier

We show using bosonization techniques, that strong forward scattering interactions between one dimensional spinless Luttinger liquids (LL) can stabilize a phase where charge-density wave, superconducting and transverse single particle hopping perturbations are irrelevant. This new phase retains its LL like properties in the directions of the chains, but with

Brian D. Moore, J. Jeff Hester, Paul A. Scowen

We present Hubble Space Telescope WFPC2 images of a portion of the bright northeast rim of NGC 6888, the nebular shell physically associated with the Wolf-Rayet star HD 192163. The exposures are taken in the light of Halpha 6563, [O III] 5007, and [S II] 6717,6731. The images are used to constrain models of the ionization structure of nebular features. From

Adam Frank, Thibaut Lery, Thomas A. Gardiner, T. W. Jones

We present simulations of the propagation of magnetized jets. This work differs from previous studies in that the cross-sectional distributions of the jets&#39;s state variables are derived from analytical models for magneto-centrifugal launching. The source is a magnetized rotator whose properties are specfied as boundary conditions. The jets in these simul

H. Pierre Noyes

Using a simple combinatorial algorithm for generating finite and discrete events as our numerical cosmology, we predict that the baryon/photon ratio at the time of nucleogenesis is $η= 1/256^4$, $Ω_{DM}/Ω_B= 12.7$ and (for a cosmological constant of $Ω_Λ=0.6\pm 0.1$ predicted on general grounds by E.D.Jones) that $0.325 > Ω_M > 0.183 $. The limits are set no

E. Meyer-Hofmeister, F. Meyer

Many black hole X-ray transients are in a low state for several decades until an outburst occurs. We interpret this outburst behaviour as a marginal occurrence of a dwarf nova type disk instability in the cool outer accretion disk. We compute the disk evolution including evaporation of matter from the cool thin disk. This evaporation process causes the trans

Sean M. Dougherty, P. M. Williams, D. L. Pollacco

We present new radio and optical observations of the colliding-wind system WR146 aimed at understanding the nature of the companion to the Wolf-Rayet star and the collision of their winds. The radio observations reveal emission from three components: the WR stellar wind, the non-thermal wind-wind interaction region and, for the first time, the stellar wind o

A. Gil de Paz, A. Aragon-Salamanca, J. Gallego, A. Alonso-Herrero

We present new near-infrared J and K imaging data for 67 galaxies from the Universidad Complutense de Madrid survey used to determine the SFR density of the local universe by Gallego et al. (1995). This is a sample of local star-forming galaxies with redshift lower than 0.045, and they constitute a representative subsample of the galaxies in the complete UCM

S. G. Korzennik, T. M. Brown, D. A. Fischer, P. Nisenson

HD 89744 is an F7 V star with mass 1.4 M, effective temperature 6166 K, age 2.0 Gy and metallicity [Fe/H]= 0.18. The radial velocity of the star has been monitored with the AFOE spectrograph at the Whipple Observatory since 1996, and evidence has been found for a low mass companion. The data were complemented by additional data from the Hamilton spectrograph

H. C. Spruit

The theory of stellar structure can be used to identify the most plausible mechanisms for the irradiance variations associated with the solar cycle. Changes in surface emissivity, i.e. the reduced cooling in spots and enhanced emission by small scale magnetic fields, are the most effective mechanisms and account for most of the observed variation. Helioseism

H. C. Spruit

Some topics in the theory of jets are reviewed. These include jet precession, unconfined jets, the origin of knots, the internal shock model as a unifying theme from protostellar jets to Gamma-ray bursts, relations between the Blandford-Znajek and MHD disk-wind models, and jet collimation in magnetic acceleration models.

Yu. P. Shitov, V. D. Pugachev, S. M. Kutuzov

The soft gamma repeater SGR 1900+14 was observed in Pushchino observatory since 1988 December using BSA radio telescope operating at 111 MHz. We have detected the pulsed radio emission (Shitov 1999) with the same 5.16 s period that was reported earlier for this object. The timing analysis has shown that this new radio pulsar PSR J1907+0919 associated with SG

S. Bensammar, A. -L. Melchior

Within 8 years, the current microlensing surveys of M31 will provide several hundred events affecting unresolved stars. They will thus allow a statistical study of the dark matter in M31&#39;s halo. The NGST will resolve these stars and constrain the mass of the corresponding lenses. In case of on-line alerts from ground-based observations, real-time NGST fo

Matts Roos, S. M. Harun-or-Rashid

In order to answer this question, we combine ten independent astrophysical constraints in the space of the density parameters $Ω_m$ of gravitating matter and $Ω_Λ$ of vacuum energy. We find that $Ω_m=0.31\pm 0.07$, $Ω_Λ=0.63\pm 0.21$, and thus $Ω_m + Ω_Λ=0.94\pm 0.22$. The total $χ^2$ is 4.1 for 8 degrees of freedom, testifying that the various systematic er

A. D. Schwope, G. Hasinger, I. Lehmann, R. Schwarz

We present a summary of an identification program of the more than 2000 X-ray sources detected during the ROSAT All-Sky Survey (Voges et al. 1999) at high galactic latitude, |b| > 30 degr, with countrate above 0.2 s-1. This program, termed the ROSAT Bright Survey RBS, is to more than 99.5% complete. A sub-sample of 931 sources with countrate above 0.2 s-1 in

K. Benabed, F. Bernardeau, L. van Waerbeke

We explore the possibility of using the B-type polarization of the CMB to map the large-scale structures of the Universe taking advantage of the lens effects on the CMB polarization. The functional relation between the B component with the primordial CMB polarization and the line-of-sight mass distribution is explicited. Noting that a sizeable fraction (at l

A. -L. Melchior, F. Viallefond, M. Guelin, N. Neininger

We report the first detection of CO in M31&#39;s bulge. The 12CO (1-0) and (2-1) lines are both detected in the dust complex D395A/393/384, at 1.3&#34; (~0.35 kpc) from the centre. From these data and from visual extinction data, we derive a CO-luminosity to reddening ratio (and a CO-luminosity to H_2 column density ratio) quite similar to that observed in t

Mario Vietri

I show here that the time-delay between the gamma ray burst proper and the onset of the afterglow is a sensitive function of the surrounding density, going from ~10s for typical disk densities to several hours for IGM densities. Since bulk Lorenz factor, explosion energy and environment density can be simultaneously determined from observations of the time-d

Ian S. McLean, Mavourneen K. Wilcox, E. E. Becklin, Donald F. Figer

Near-infrared spectroscopic observations of a sample of very cool, low-mass objects are presented with higher spectral resolution than in any previous studies. Six of the objects are L-dwarfs, ranging in spectral class from L2 to L8/9, and the seventh is a methane or T-dwarf. These new observations were obtained during commissioning of NIRSPEC, the first hig

R. Scranton, S. Dodelson

Extracting the three dimensional power spectrum from the 2D distribution of galaxies has become a standard tool of cosmology. This extraction requires some assumptions about the scaling of the power spectrum with redshift; all treatments to date assume a simple power law scaling. In reality, different scales grow at different rates, due to non-linearities. W

R. Narevich, R. E. Prange, Oleg Zaitsev

Eigenstates and energy levels of a square quantum billiard in a magnetic field, or with an Aharonov-Bohm flux line, are found in quasiclassical approximation, that is, for high enough energy. Explicit formulas for the energy levels and wavefunctions are found. A number of interesting states are shown, together with their wavefunctions. Some states are diamag

Z. Y. Weng, D. N. Sheng, C. S. Ting

We present a self-consistent RVB theory which unifies the metallic (superconducting) phase with the half-filling antiferromagnetic (AF) phase. Two crucial factors in this theory include the RVB condensation which controls short-range AF spin correlations and the phase string effect introduced by hole hopping as a key doping effect. We discuss both the unifor

B. L. Altshuler, D. L. Maslov, V. M. Pudalov

The goal of this paper is to highlight several issues which are most crucial for the understanding of the ``metal-insulator transition&#39;&#39; in two dimensions. We discuss some common problems in interpreting experimental results on high mobility Si MOSFETs. We analyze concepts and methods used to determine the critical density of electrons at the metal-i

Qimiao Si

Pedagogical discussions are given on what constitutes a signature of spin-charge separation. A proposal is outlined to probe spin-charge separation in the normal state of the high $T_c$ cuprates using spin transport. Specifically, the proposal is to compare the temperature dependences of the spin resistivity and electrical resistivity: Spin-charge separation

Ch. Raab, J. Eschner, J. Bolle, H. Oberst

Resonance fluorescence of a single trapped ion is spectrally analyzed using a heterodyne technique. Motional sidebands due to the oscillation of the ion in the harmonic trap potential are observed in the fluorescence spectrum. From the width of the sidebands the cooling rate is obtained and found to be in agreement with the theoretical prediction.

J. J. M. Verbaarschot, T. Wettig

Random matrix theory is a powerful way to describe universal correlations of eigenvalues of complex systems. It also may serve as a schematic model for disorder in quantum systems. In this review, we discuss both types of applications of chiral random matrix theory to the QCD partition function. We show that constraints imposed by chiral symmetry and its spo

Robert Oeckl

We show that there is a duality exchanging noncommutativity and non-trivial statistics for quantum field theory on R^d. Employing methods of quantum groups, we observe that ordinary and noncommutative R^d are related by twisting. We extend the twist to an equivalence for quantum field theory using the framework of braided quantum field theory. The twist exch

R. Manvelyan, A. C. Petkou

We discuss the two- and three-point functions of the SO(5) R-current of the (2,0) tensor multiplet in d=6, using AdS/CFT correspondence as well as a free field realization. The results obtained via AdS/CFT correspondence coincide with the ones from a free field calculation up to an overall 4N^3 factor. This is the same factor found recently in studies of the

S. Deser, V. Pascalutsa, A. Waldron

We study the general non-minimally coupled charged massive spin 3/2 model both for its low energy phenomenological properties and for its unitarity, causality and degrees of freedom behaviour. When the model is viewed as an effective theory, its parameters (after ensuring the correct excitation count) are related to physical characteristics, such as the magn

Subal Das Gupta, Charles Gale

It has been suggested that collisions between deformed shapes will lead to interesting effects on various observables such as K production and elliptic flow. Simple formulae can be written down which show how to choose the colliding beams which will maximise the effects of deformation.

Bryan Gaensler, Douglas Bock, Ben Stappers

We report on a deep radio search for a pulsar wind nebula associated with the radio-quiet neutron star RX J0822-4300 in the supernova remnant Puppis A. The well-determined properties of Puppis A allow us to constrain the size of any nebula to less than 30 arcsec; however we find no evidence for such a source on any spatial scale up to 30 arcmin. These non-de

G. Bonvicini

We present a search for direct CP violation in B+- -> J/psi K+- and B+- -> psi(2S) K+- decays. In a sample of 9.7 million B meson pairs collected with the CLEO detector, we have fully reconstructed 534 B+- -> J/psi K+- and 120 B+- -> psi(2S) K+- decays with very low background. We have measured the CP-violating charge asymmetry to be (+1.8+-4.3[stat]+-0.4[sy

Shung-ichi Ando, Tae-Sun Park, Dong-Pil Min

The $pp\to ppπ^0$ cross section near threshold is computed up to one-loop order including the initial and final state interactions using the hybrid heavy baryon chiral perturbation theory and the counting rule a la Weinberg. With the counter terms whose coefficients are fixed by the resonance-saturation assumption, we find that the one-loop contributions are

G. Pugliese, H. Falcke, Y. Wang, P. L. Biermann

The relation between the cosmological evolution of the jet-disk symbiosis model for GRBs and the cosmic rays energy distribution is presented. We used two different Star Formation Rates (SFR) as a function of redshift and a Luminosity Function (LF) distribution to obtain the distribution in fluence of GRBs in our model and compare it with the data. We show a

G. Van Hooydonk

We show that Coulomb&#39;s law is a universal molecular function. Charge inversion in one atom (handedness or chirality) generates a switch from atom-atom to atom-antiatom systems. this switch reduces the 10 term Hamiltonian for 4-particle systems to only 1 or 2 terms. This reduced parity adapted Hamiltonian accounts for observed PECs for atom-atom systems (

M. Mueller, H. -J. Mikeska

We investigate the elementary excitations of quasi one-dimensional S=1/2 systems built up from zig-zag chains with general isotropic exchange constants, using exact (Lanczos) diagonalization for 24 spins and series expansions starting from the decoupled dimer limit. For the ideal one-dimensional zig-zag chain we discuss the systematic variation of the basic

N. N. Achasov, A. A. Kozhevnikov

The arguments are put forward that the many pion decays omega ->2 pi^+ 2 pi^- pi^0 and pi^+ pi^- 3 pi^0 provide an ideal test site for testing the predictions of chiral models of the vector meson decays into many pions. Using the approach based on the Weinberg Lagrangian or, in a new language, the Lagrangian of hidden local symmetry added with the term induc

J. M. Carmona, M. D&#39;Elia, A. Di Giacomo, B. Lucini

In the study of QCD dynamics, C* boundary conditions are physically relevant in certain cases. In this paper we study the implementation of these boundary conditions in the lattice formulation of full QCD with staggered fermions. In particular, we show that the usual even-odd partition trick to avoid the redoubling of the fermion matrix is still valid in thi

H1 Collaboration, C. Adloff

The reaction e+p --> e+X is studied with the H1 detector at Hera. The data cover momentum transfers Q^2 between 200 GeV^2 and 30,000 GeV^2 and correspond to an integrated luminosity of 35.6 pb^(-1). The differential cross section dsigma/dQ^2 is compared to the Standard Model expectation for neutral current scattering and analysed to search for bar(e)e bar(q)

C. F. Chang, J. -Y. Lin, H. D. Yand

We have measured low-temperature specific heat C(T, H) of La1.9Sr0.1Cu1-xZnxO4 (x=0, 0.01, and 0.02) both in zero and applied magnetic fields. A pronounced dip of C/T below 2 K was first observed in Zn-doped samples, which is absent in the nominally clean one. If the origin of the dip in C/T is electronic, the quasiparticle density of states N(E) in Zn-doped

Takeo Inami, Yorinori Saito, Masayoshi Yamamoto

We study the ultraviolet properties of the supersymmetric CP^{N-1} sigma model in three dimensions to next-to-leading order in the 1/N expansion. We calculate the β-function to this order and verify that it has no next-to-leading order corrections.

T. A. Heim, K. Hencken, D. Trautmann, G. Baur

The experimental determination of the lifetime of pionium provides a very important test on chiral perturbation theory. This quantity is determined in the DIRAC experiment at CERN. In the analysis of this experiment, the breakup probabilities of of pionium in matter are needed to high accuracy as a theoretical input. We study in detail the influence of the t

Pavel Etingof, David Kazhdan, Alexander Polishchuk

Let V be a finite dimensional vector space over a local field. Let us say that a complex function on V is elementary if it is a product of the additive character of a rational function Q on V and multiplicative characters of polynomials on V. In this paper we study when the Fourier transform of an elementary function is elementary. If Q has a nonzero Hessian

Smitha Vishveshwara, Matthew P. A. Fisher

In this paper, a delocalization-localization transition within the superconducting state is explored. The symmetries of the Bogoliubov deGennes Hamiltonian endow the two associated superconducting phases - the thermal metal and the thermal insulator-, and the critical point between them with properties that are in stark contrast with analogous phases in norm

T. Eggeling, R. F. Werner

We study separability properties in a 5-dimensional set of states of quantum systems composed of three subsystems of equal but arbitrary finite Hilbert space dimension. These are the states, which can be written as linear combinations of permutation operators, or, equivalently, commute with unitaries of the form UxUxU. We compute explicitly the following sub