May 1997 arXiv papers — page 4

Yoshinobu Kuramashi

Renormalization factors for local vector and axial vector currents for the Wilson quark action are perturbatively calculated to one loop order including finite quark masses from the ratio of the on-shell quark matrix elements in the Feynman gauge defined on the lattice and in the continuum. For large quark masses of order unity in lattice units, we find that

Wei Lu

I clarify the mistakes in the original version hep-ph/9705427 about the phase space factor for the one-photon production in electron-proton scattering and confirm that the earlier result given by Kroll, Schürmann and Guichon is right.

Paolo Zanardi

A model for a quantum register $\cal R$ made of $N$ replicas of a $d$-dimensional quantum system (cell) coupled with the environment, is studied by means of a Born-Markov Master Equation (ME). Dissipation and decoherence are discussed in various cases in which a sub-decoherent enconding can be rigorously found. For the qubit case ($d=2$) we have solved, for

P. Zanardi, M. Rasetti

In this paper we study a model quantum register $\cal R$ made of $N$ replicas (cells) of a given finite-dimensional quantum system S. Assuming that all cells are coupled with a common environment with equal strength we show that, for $N$ large enough, in the Hilbert space of $\cal R$ there exists a linear subspace ${\cal C}_N$ which is dynamically decoupled

Pascal de Theije, Eelco van Kampen, Remco Slijkhuis

We study the influence of the various parameters of scenarios of large-scale structure formation on properties of galaxy clusters, and investigate which cluster properties are most sensitive to these parameters. We present a set of large N-body simulations and derive the intrinsic properties of galaxy clusters in these simulations, which represent a volume o

Masahide Sasaki, Kentaro Kato, Masayuki Izutsu, Osamu Hirota

When classical information is sent through a quantum channel of nonorthogonal states, there is a possibility that transmittable classical information exceeds a channel capacity in a single use of the initial channel by extending it into multi-product channel. In this paper, it is shown that this remarkable feature of a quantum channel, so-called superadditiv

Norifumi Hayaishi, Kei Miki

Utilizing the multiplicative formula of universal R matrix, the correspondence between the L operators and Drinfeld's generators is explicitly calculated for quantum group U_q(g) with g=A_l^{(1)}, B_l^{(1)}, C_l^{(1)}, D_l^{(1)}.

Giovanni Felder, Vitaly Tarasov, Alexander Varchenko

The elliptic quantum Knizhnik-Zamolodchikov-Bernard (qKZB) difference equations associated to the elliptic quantum group $E_{τ,η}(sl_2)$ is a system of difference equations with values in a tensor product of representations of the quantum group and defined in terms of the elliptic R-matrices associated with pairs of representations of the quantum group. In t

A. R. Gover, R. B. Zhang

Quantum homogeneous vector bundles are introduced by a direct description of their sections in the context of Woronowicz type compact quantum groups. The bundles carry natural topologies inherited from the quantum groups, and their sections furnish projective modules over algebras of functions on quantum homogeneous spaces. Further properties of the quantum

V. M. Shabaev

The quantum electrodynamic theory of the nuclear recoil effect in atoms to all orders in αZ is formulated. The nuclear recoil corrections for atoms with one and two electrons over closed shells are considered in detail. The problem of the composite nuclear structure in the theory of the nuclear recoil effect is discussed.

Jon D. Pelletier, Donald L. Turcotte

A review paper considering space-time variability of climate, sedimentation, and geomagnetism.

G. N. Throumoulopoulos, H. Tasso

It is proved that (a) the solutions of the ideal magnetohydrodynamic equation, which describe the equlibrium states of a cylindrical plasma with purely poloidal flow and arbitrary cross sectional shape [G. N. Throumoulopoulos and G. Pantis, Plasma Phys. and Contr. Fusion 38, 1817 (1996)] are also valid for incompressible equlibrium flows with the axial veloc

Jon D. Pelletier

Power spectral analyses of soil moisture variability are carried out from scales of 100 m to 10 km on the microwave remotely-sensed data from the Washita experimental watershed during 1992. The power spectrum S(k) has an approximately power-law dependence on wave number k with exponent -1.8. This behavior is consistent with the behavior of a stochastic diffe

Jon D. Pelletier

Power spectral analyses of the dipole moment of the earth's magnetic field inferred from ocean sediment cores and archeomagnetic data from time scales of 100 yr to 4 Myr have been carried out. The power spectrum is proportional to 1/f where f is the frequency. These analyses compliment previous work which has established a 1/f^2 spectrum for variations a

Jon D. Pelletier

The power spectrum S of linear transects of the earth's topography is often observed to be a power-law function of wave number k with exponent close to -2: S(k) is proportional to k^-2. In addition, river networks are fractal trees that satisfy many power-law or fractal relationships between their morphologic components. A model equation for the evolutio

Luis Gonzalez-Mestres

Lorentz symmetry has been tested at low energy with great accuracy, but its extrapolation to very high-energy phenomena is much less well established. We expect a possible breaking of Lorentz symmetry to be a very high energy and very short distance phenomenon, compatible with existing data. If textbook special relativity is only an approximate property of t

Luis Gonzalez-Mestres

Special relativity has been tested at low energy with great accuracy, but its extrapolation to very high-energy phenomena is much less well established. Introducing a critical distance scale, a , below 10E-25 cm (the wavelength scale of the highest-energy observed cosmic rays) allows to consider models, compatible with standard tests of special relativity, w

H. Oberhummer, A. N. Ivanov, N. I. Troitskaya, M. Faber

The present status of the nuclear reaction rates determining the solar neutrino flux is discussed. This includes the reaction rates for the two branching ratios of the three pp-chains involving the reactions 3He(3He,2p)4He and 3He(4He,gamma)7Be for the first branching, and 7Be(e-,nu_e)7Li and 7Be(p,gamma)7B for the second branching. Mainly we will concentrat

P. K. Panda, A. Mishra, J. M. Eisenberg, W. Greiner

We study here hot nuclear matter in the quark meson coupling (QMC) model which incorporates explicitly quark degrees of freedom, with quarks coupled to scalar and vector mesons. The equation of state of nuclear matter including the composite nature of the nucleons is calculated at finite temperatures. The calculations are done taking into account the medium-

R. Caracciolo, A. De Pace, H. Feshbach, A. Molinari

A statistical theory of the mean field is developed. It is based on the proposition that the mean field can be obtained as an energy average. Moreover, it is assumed that the matrix elements of the residual interaction, obtained after the average interaction is removed, are random with the average value of zero. With these two assumptions one obtains explici

Klaus Strobel, Fridolin Weber, Manfred K. Weigel, Christoph Schaab

The modern nucleon-nucleon interaction of Myers and Swiatecki, adjusted to the properties of finite nuclei, the parameters of the mass formula, and the behavior of the optical potential is used to calculate the properties of $β$--equilibrated neutron star matter, and to study the impact of this equation of state on the properties of (rapidly rotating) neutro

Urs Achim Wiedemann

A Fourier inversion problem lies at the heart of determining spatio-temporal characteristica of the final stage of a heavy ion collision: From the measured two-particle momentum correlations C(p_1,p_2) of identical particles, pions say, a Hanbury-Brown /Twiss (HBT) interferometric analysis aims at extracting as much information as possible about the Wigner p

F. A. Dilkes, D. G. C. McKeon, K. Nguyen

We consider several renormalizable, scale free models in three space-time dimensions which involve scalar and spinor fields. The Yukawa couplings are bilinear in both the spinor and scalar fields and the potential is of sixth order in the scalar field. In a model with a single scalar field and a complex Fermion field in three Euclidean dimensions, the coupli

P. Mukherjee

We consider a (2+1) dimensional nonlinear O(3) sigma model with its U(1) subgroup gauged along with the inclusion of a self-interaction having symmetry breaking minima.The gauge field dynamics is governed by the Maxwell term.The model is shown to support topologically stable purely magnetic self-dual vortices.

Akira Kokado, Gaku Konisi, Takesi Saito, Yutaka Tada

In the Brans-Dicke(BD) theory on $M_{4}\times Z_{2}$ geometry the geometrical meaning of the torsion is clarified. The BD theory on $M_{4}\times Z_{2}$ is rederived by taking into account of a new isometry condition.

E. Accomando

We describe the physics potential of $e^+e^-$ linear colliders in this report. These machines are planned to operate in the first phase at a center-of --mass energy of 500 GeV, before being scaled up to about 1 TeV. In the second phase of the operation, a final energy of about 2 TeV is expected. The machines will allow us to perform precision tests of the he

B. F. L. Ward, S. Jadach

We show that the recently derived renormalization group improved Yennie-Frautschi-Suura (YFS) exponentiation of soft $(k_o\to 0)$ gluons in QCD is fully compatible with the usual Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution of the structure functions of hadrons in the respective hadron-hadron hard interactions. We show how to implement the YF

Henning Genz

Partial conservation of the nine axial currents $A^β_μ$ for $β=0,1,...,8$ applied to the vacuum expectation values of the equal-time commutators of the nine axial charges $Q_A^α(x_0)$ for $α=0,1,...,8$ with the corresponding axial current divergences $\partial^μA_μ^β$ implies that the non-vanishing current quark masses $m_u, m_d, m_s$ of the light quarks $u,

L. McLerran

I discuss small x physics and its implications at very high energies. At very high energy the density of partons becomes so large that much of the physics can be described using weak coupling methods in QCD. This may allow for a solution to problems such as the asymptotic nature of deep inelastic scattering at fixed momentum transfer, unitarization, and mult

J. Dias de Deus, C. Pajares, C. A. Salgado

At very high energy the same universal relation between the multiparticle or the transverse energy distribution associated to a rare event $C$, $P_C$ and the corresponding minimum bias distribution P, $P_C(ν)\equiv ν/<ν> P(ν)$, $ν\equiv n$ or $E_T$ works for nucleus-nucleus collisions as well as for hadron-hadron collisions. This suggests that asymptotically

Guey-Lin Lin

Having a mass comparable to the weak scale, the top quark may have a sizable flavor changing couplings to Higgs bosons. We show that such couplings can be probed at the LHC through the parton subprocess $c(\bar c)g \to t (\bar t)A^0$, where the pseudoscalar $A^0$ subsequently decays into $t \bar c$ or ${\bar t} c$, giving rise to the intriguing final state o

M. A. Ivanov, V. E. Lyubovitskij

The gamma(*) pi(0) -> gamma form factor is obtained within the Lagrangian quark model with separable interaction known to provide a good description of the pion observables at low energies. The pion-quarks vertex is chosen in a Gaussian form. The form factor obtained is close to the available experimental data and reaches smoothly the Brodsky-Lepage limit at

R. N. Faustov, V. O. Galkin, A. V. Tatarintsev, A. S. Vshivtsev

The method reducing the solution of the Schroedinger equation for several types of power potentials to the solution of the eigenvalue problem for the infinite system of algebraic equations is developed. The finite truncation of this system provides high accuracy results for low-lying levels. The proposed approach is appropriate both for analytic calculations

Gye T. Park, Kang Young Lee

We update the analysis of the precision electroweak tests in terms of 4 epsilon parameters, $ε_{1,2,3,b}$, to obtain more accurate experimental values of them by taking into account the new LEP data released at the 28th ICHEP (1996, Poland). We also compute $ε_1$ and $ε_b$ in the context of the no-scale $SU(5)\times U(1)$ supergravity model to obtain the upd

Seungho Choe

There have been arguments about hadronic molecules, which are weakly-bound states of two or more hadrons. We investigate the possibility of some candidates (f0 (980), a0 (980), f0 (1500), f0 (1710), etc.) using QCD sum rule approach and compare our results with multiquark states in the MIT bag model. We find that f0 (1500), f0 (1710) can be good candidates f

Merle Michael Robinson, Jacek Ziabicki

We examine a class of Froggatt-Nielsen models with an anomalous U(1) as the flavor dependent symmetry. Anomaly cancellation and unbroken supersymmetry impose constraints on the U(1)_X charges of the fermions and the vacuum expectation values of the symmetry-breaking scalars. We show by example that it is possible to find models that reproduce the observed ma

JLQCD Collaboration, S. Aoki, M. Fukugita, S. Hashimoto

The kaon B parameter is calculated in quenched lattice QCD with the Wilson quark action. The mixing problem of the Δs=2 four-quark operators is solved non-perturbatively with full use of chiral Ward identities, and this method enables us to construct the weak four-quark operators exhibiting good chiral behavior. We find B_K(NDR, 2GeV)=0.562(64) in the contin

Hartmut Wittig

The status of lattice calculations of heavy-light decay constants and of the $B$ parameter $B_B$ is reviewed. After describing the lattice approach to heavy quark systems, the main results are discussed, with special emphasis on the systematic errors in present lattice calculations. A detailed analysis of the continuum limit for decay constants is performed.

Matt Visser

The energy conditions of Einstein gravity (classical general relativity) are designed to extract as much information as possible from classical general relativity without enforcing a particular equation of state for the stress-energy. This systematic avoidance of the need to specify a particular equation of state is particularly useful in a cosmological sett

Carl H. Brans

Scalar fields have had a long and controversial life in gravity theories, having progressed through many deaths and resurrections. The first scientific gravity theory, Newton&#39;s, was that of a scalar potential field, so it was natural for Einstein and others to consider the possibility of incorporating gravity into special relativity as a scalar theory. T

Soren Holst, Peter Peldan

The observation that the 2+1 dimensional BTZ black hole can be obtained as a quotient space of anti-de Sitter space leads one to ask what causal behaviour other such quotient spaces can display. In this paper we answer this question in 2+1 and 3+1 dimensions when the identification group has one generator. Among other things we find that there does not exist

Hideo Kodama

In this paper we investigate the canonical structure of diffeomorphism invariant phase spaces for spatially locally homogeneous spacetimes with 3-dimensional compact closed spaces. After giving a general algorithm to express the diffeomorphism-invariant phase space and the canonical structure of a locally homogeneous system in terms of those of a homogeneous

N. K. Wilkin, Henrik Jeldtoft Jensen

We report results for a 3D simulation of a layered superconductor. There are two significant temperatures. The first corresponds to melting of the vortex lattice in the a-b plane (T_ab) and the second to decoupling of the layers (T_dc) with T_ab \le T_ dc. The decoupling is found to be a first order transition with an associated entropy of ~0.25-0.4 k_B/panc

L. L. Bonilla, I. R. Cantalapiedra, G. Gomila, J. M. Rubi

A general asymptotic analysis of the Gunn effect in n-GaAs under general boundary conditions for metal-semiconductor contacts is presented. Depending on the parameter values in the boundary condition of the injecting contact, different types of waves mediate the Gunn effect. The periodic current oscillation typical of the Gunn effect may be caused by moving

Atsuhiro Kitazawa, Kiyohide Nomura

We study the phase diagram of S=3/2 and S=2 bond-alternating spin chains numerically. In previous papers, the phase diagram of S=1 XXZ spin chain with bond-alternation was shown to reflect the hidden $Z_{2}\times Z_{2}$ symmetry. But for the higher S Heisenberg spin chain, the successive dimerization transition occurs, and for anisotropic spin chains the pha

G. Gomila, J. M. Rubi, I. R. Cantalapiedra, L. L. Bonilla

A general formulation of boundary conditions for semiconductor-metal contacts follows from a phenomenological procedure sketched here. The resulting boundary conditions, which incorporate only physically well-defined parameters, are used to study the classical unipolar drift-diffusion model for the Gunn effect. The analysis of its stationary solutions reveal

Reinhard Baltin, Karl-Heinz Wagenblast

We study the ground state phase diagram and the critical properties of interacting Bosons in one dimension by means of a quantum Monte Carlo technique. The direct experimental realization is a chain of Josephson junctions. For finite-range interactions we find a novel intermediate phase which shows neither solid order nor superfluidity. We determine the loca

M. Fogelström, D. Rainer, J. A. Sauls

Theoretical results for the ab-plane tunneling conductance in the d-wave model for high Tc superconductors are presented. The d-wave model predicts surface bound states below the maximum gap. A sub-dominant order parameter, stabilized by the surface, leads to a splitting of the zero-bias conductance peak (ZBCP) in zero external field and to spontaneous surfa

Heinz Horner, Anthea Bethge

The performance of large neural networks can be judged not only by their storage capacity but also by the time required for learning. A polynomial learning algorithm with learning time $\sim N^2$ in a network with $N$ units might be practical whereas a learning time $\sim e^N$ would allow rather small networks only. The question of absolute storage capacity

Goetz S. Uhrig

The data on the dispersion of the magnetic excitations of CuGeO_3 in the spin-Peierls dimerized phase are analyzed. On the basis of the lattice structure it is shown that even along the chains the $d=2$ character cannot be neglected. The symmetry of the dispersion differs from the one assumed so far. The magnetic resonance data is reinterpreted. The possibil

W. Kinzel, R. Urbanczik

On-line learning of a rule given by an N-dimensional Ising perceptron, is considered for the case when the student is constrained to take values in a discrete state space of size $L^N$. For L=2 no on-line algorithm can achieve a finite overlap with the teacher in the thermodynamic limit. However, if $L$ is on the order of $\sqrt{N}$, Hebbian learning does ac

Michel Bockstedte, Alexander Kley, Joerg Neugebauer, Matthias Scheffler

The package &#34;fhi96md&#34; is an efficient code to perform density-functional theory total-energy calculations for materials ranging from insulators to transition metals. The package employs first-principles pseudopotentials, and a plane-wave basis-set. For exchange and correlation both the local density and generalized gradient approximations are impleme

L. A. Maksimov, A. F. Barabanov, R. O. Kuzian

Within the frameworks of spin-polaron concept and the spherically symmetric state for the antiferromagnetic spin background, the one-particle motion is studied for two-dimensional Kondo-lattice. The elemetary excitations are represented as a Bloch superposition of four one-site electron states: two local states- a bare electron state and a local spin-polaron

Carsten van de Bruck

We use the velocity-dependent one-scale model by Martins & Shellard to investigate the evolution of a GUT long cosmic string network in arbitrary Friedmann-Lemaitre models. Four representative models are used to show that in general there is no scaling solution. The implications for structure formation are briefly discussed.

P. Andreani, A. Franceschini, G. L. Granato

We use photometric data, from the optical to the mm for a large sample of optically selected radio-quiet quasars, at low and high redshifts, to test emission models from circum-nuclear dusty torii around them. Model parameters, such as dust mass, temperature distributions and torus sizes are inferred, under the assumption that the dust is heated only by the

G. Cayrel de Strobel, C. Soubiran, E. D. Friel, N. Ralite

The Catalogue of [Fe/H] determinations has been updated and now includes 5946 determinations for 3247 stars (with 751 stars in 84 associations, clusters or galaxies). The 700 bibliographical references are complete up to December 1995 and refer only to [Fe/H] determinations obtained from high-resolution spectroscopic observations. The Catalogue also gives th

John M. Dickey

Absorption lines at $λ$ 21-cm are detected in the Stokes Q and U components of the Galactic synchrotron background. The lower limit distance implied for the emission region is 2 kpc in the direction (l,b) = (329.5$^{\circ}$,+1.15$^{\circ}$). The Australia Telescope Compact Array has the capability of mapping this absorption over large areas of the Galactic p

J. Hisano, M. Shifman

We obtain exact relations (valid to all orders in the coupling constant) for the running gaugino mass in supersymmetric gauge theories, treating the soft supersymmetry breaking effects in the linear approximation. If a supersymmetry breaking squark (selectron) mass term is introduced, our relation connects the renormalization group equation for this term wit

Dimitri Polyakov

We review and develop the formalism of ghost number cohomologies, outlined in our previous work, to classify the quantum states of M-theory. We apply this formalism to the matrix formulation of M-theory to obtain NSR superstring action from dimensionally reduced matrix model. The BPS condition of the matrix theory is related to the worldsheet reparametrizati

Nemanja Kaloper, Krzysztof Meissner

In this article we give a calculation of the two-loop $σ$-model corrections to the T-duality map in string theory. We use the effective action approach, and analyze two-loop corrections in a specific subtraction scheme. Focusing on backgrounds which have a single Abelian isometry, we find the explicit form for the $O(α&#39;)$ modifications of the lowest orde

K. S. Babu, Christopher Kolda, John March-Russell

We demonstrate that in the presence of mixing between different scalar leptoquark multiplets it is possible to simultaneously account for the HERA high-$Q^2$ neutral current anomaly, and produce a charged current anomaly of comparable magnitude. The reduced branching ratio to electrons and jets of the lightest leptoquark state results in a significant weaken

Ya. M. Blanter, A. D. Mirlin

The weak localization correction and the mesoscopic fluctuations of the polarizability and the capacitance of a small disordered sample are studied systematically in 2D and 3D geometries. While the grand canonical ensemble calculation gives the positive magnetopolarizability, in the canonical ensemble (appropriate for isolated samples) the sign of the effect

Eyvind Aker, Knut Jorgen Maloy, Alex Hansen, G. George Batrouni

We investigate a two-dimensional network simulator capable of modeling different time dependencies in two-phase drainage displacements. In particular, we focus on the temporal evolution of the pressure due to capillary and viscous forces and the time dependence of the interface between the two liquids. The dynamics of the capillary effect are taken into acco

George Gasper, Mizan Rahman

Here are the latest errata, etc., to the Gasper and Rahman &#34;Basic Hypergeometric Series&#34; book. Any additional errata will be added to the end of the last list.

M. Yu. Kalmykov, D. I. Kazakov

A new way how to calculate the off-shell renormalization functions within the $R^2$-gravity has been proposed. The one-loop renormalization group equations in the approach suggested have been constructed. The behaviour of effective potential for an massless scalar field interacting with the quantum gravitational field has been analyzed in this approach.

J. Ellis, S. Lola, K. Sridhar

We explore the possible interpretation of the large-$Q^2$ anomaly reported by the H1 and ZEUS collaborations in terms of stop squark production off a strange quark in the proton via an R-violating interaction. This &#34;strange stop&#34; interpretation is constrained by LEP measurements of the $Z \to e^+ e^-$ decay rate in addition to constraints from the el

M. Stratmann

We present a brief description of the determination of the two-loop spin-dependent time-like splitting functions relevant for the NLO evolution of polarized fragmentation functions. Our calculation based on the analytic continuation of the corresponding space-like results obtained within the light-cone gauge method proposed by Curci, Furmanski, and Petronzio

William Arveson

It is known that every semigroup of normal completely positive maps $P = {P_t: t\geq 0}$ of $B(H)$, satisfying $P_t(1) = 1$ for every $t\geq 0$, has a minimal dilation to an E_0-semigroup acting on $B(K)$ for some Hilbert space K containing H. The minimal dilation of P is unique up to conjugacy. In a previous paper a numerical index was introduced for semigr

William Arveson

A numerical index is introduced for semigroups of completely positive maps of $\Cal B(H)$ which generalizes the index of E_0-semigroups. It is shown that the index of a unital completely positive semigroup agrees with the index of its dilation to an E_0-semigroup, provided that the dilation is minimal.

William Arveson

An E_0-semigroup acting on B(H) is called pure if the intersection of the ranges $α_t(B(H))$, $t>0$, is the algebra of scalars. We determine all pure E_0-semigroups which have a weakly continuous invariant state $ω$ and which are minimal in an appropriate sense. In such cases, for every normal state $ρ$ there is convergence to equilibrium in the trace norm $

D. V. Khveshchenko, Michael Reizer

We develop a unified treatment of the piesoelectric coupling between two-dimensional electrons and bulk phonons in both cases of zero and strong magnetic fields, the latter corresponding to even denominator filling fractions. In contrast to the case of coupling via the deformation potential, the leading contributions due to impurity-renormalized electron-pho

David Vanderbilt

The theory of the macroscopic field appearing in the Kohn-Sham exchange-correlation potential for dielectric materials, as introduced by Gonze, Ghosez and Godby, is reexamined. It is shown that this Kohn-Sham field cannot be determined from a knowledge of the local state of the material (local crystal potential, electric field, and polarization) alone. Inste

Kwok-On Ng, David Vanderbilt

We present self-consistent ab-initio total-energy and electronic-structure calculations on stoichiometric and non-stoichiometric TiO2 (110) surfaces. Scanning tunneling microscopy (STM) topographs are simulated by calculating the local electronic density of states over an energy window appropriate for the experimental positive-bias conditions. We find that u

Yu. N. Gornostyrev, M. I. Katsnelson, A. V. Trefilov

To describe structural peculiarities in inhomogeneous media caused by the tendency to the close packing of atoms a formalism based on the using of the Riemann geometry methods (which were successfully applied lately to the description of structures of quasicrystals and glasses) is developed. Basing on this formalism we find in particular the criterion of sta

Z. Ivezic, D. M. Christodoulou

We have searched the IRAS Point Source Catalog and HIRES maps for young stellar objects (YSOs) in the direction of five \HI high-velocity clouds (HVCs). In agreement with optical searches in the halo, no evidence was found for extensive star-forming activity inside the high-latitude HVCs. Specifically, we have found no signs of star formation or YSOs in the

Fridolin Weber, Norman K. Glendenning, Shouyong Pei

For the past 20 years it had been thought that the coexistence phase of the confined hadronic and quark matter phases, assumed to be a first order transition, was strictly excluded from neutron stars. This, however, was due to a seemingly innocuous idealization which has approximated away important physics. The reason is that neutron stars constitute multi-c

Sandra Di Rocco, Kristian Ranestad

We construct examples of smooth surfaces S in P^6 with no trisecant lines. This list includes examples of surfaces not cut out by quadrics. We prove that unless S has a finite number of disjoint $(-1)$-lines, and each one meets some other line L on the surface with L^2\leq -2, and S is not an inner projection from P^7 the surface belongs to the list of examp

Max Tegmark

We apply state-of-the art data analysis methods to a number of fictitious CMB mapping experiments, including 1/f noise, distilling the cosmological information from time-ordered data to maps to power spectrum estimates, and find that in all cases, the resulting error bars can we well approximated by simple and intuitive analytic expressions. Using these appr

J. W. Bolesta, H. Bradner, U. Camerini, J. Clem

We report the results of a search for neutrino-induced particle cascades using a deep ocean water Cherenkov detector. The effective mass of the detector, a string of seven 40 cm diameter photomultipliers at 5.2 m spacing, is found through simulation analysis to be surprisingly large: greater than 1 megaton of water at incident neutrino energies of 1 PeV. We

David B. Kaplan, Francois Lepeintre, Martin Schmaltz

Strongly coupled supersymmetric theories can give rise to composite quarks and leptons at low energy. We show that the internal structure of these particles can explain the origin of three generations and provide a qualitative understanding of mass ratios and mixing angles between the different flavors of fermions, all within a renormalizable theory. The mai

Hagen Kleinert, Sergei V. Shabanov

A supersymmetric path integral representation is developed for stochastic processes whose Langevin equation contains any number N of time derivatives, thus generalizing the Langevin equation with inertia studied by Kramers, where N=2. The supersymmetric action contains N fermion fields with first-order time derivatives whose path integral is evaluated for fe

T. Banks, W. Fischler, N. Seiberg, L. Susskind

In this paper we consider features of graviton scattering in Matrix theory compactified on a 2-torus. The features which interest us can only be determined by nonperturbative effects in the corresponding 2+1 dimensional super Yang Mills theory. We show that the superconformal symmetry of strongly coupled Super Yang Mills Theory in 2+1 dimensions almost deter

Nima Arkani-Hamed, Hitoshi Murayama

We clarify the notion of Wilsonian renormalization group (RG) invariance in supersymmetric gauge theories, which states that the low-energy physics can be kept fixed when one changes the ultraviolet cutoff, provided appropriate changes are made to the bare coupling constants in the Lagrangian. We first pose a puzzle on how a quantum modified constraint (such

F. Antonuccio, S. J. Brodsky, S. Dalley

There exist an infinite number of exact small momentum fraction-$x$ boundary conditions on light-cone wavefunctions of bound states in gauge theory. They are necessary for finite expectation values of the invariant mass operator and relate components of the wavefunction from different Fock sectors. We illustrate their consequences by analyzing the small-$x$

Daijiro Suematsu

The electric dipole moment of an electron (EDME) is investigated in the supersymmetric extra U(1) models. Neutralino sector is generally extended in these models and then the neutralino contribution will be important for the analysis of the EDME. Kinetic term mixings of abelian gauginos are taken into account in our analysis. Numerical results for the extra

Laurent Laloux, Pierre Le Doussal

We study out of equilibrium dynamics and aging for a particle diffusing in one dimensional environments, such as the random force Sinai model, as a toy model for low dimensional systems. We study fluctuations of two times $(t_w, t)$ quantities from the probability distribution $Q(z,t,t_w)$ of the relative displacement $z = x(t) - x(t_w)$ in the limit of larg

Florian W. J. Weig, Peter V. Coveney, Bruce M. Boghosian

We investigate the growth kinetics of binary immiscible fluids and emulsions in two dimensions using a hydrodynamic lattice-gas model. We perform off-critical quenches in the binary fluid case and find that the domain size within the minority phase grows algebraically with time in accordance with theoretical predictions. In the late time regime we find a gro

A. Burrows, M. Marley, W. B. Hubbard, J. I. Lunine

We present the results of a new series of non-gray calculations of the atmospheres, spectra, colors, and evolution of extrasolar giant planets (EGPs) and brown dwarfs for effective temperatures below 1300 K. This theory encompasses most of the mass/age parameter space occupied by substellar objects and is the first spectral study down to 100 K. These calcula

Ignatios Antoniadis, Pawel O. Mazur, Emil Mottola

In a recent paper of Linde and Mukhanov, a hybrid inflationary model with nongaussian density perturbations and a ``blue&#39;&#39; spectral index n > 1 was presented. In this comment we point out that this model can be considered as a particular realization of the general framework for the spectrum and statistics of the CMBR we proposed in astro-ph/9611208,

J. Kaluzny, K. Z. Stanek, P. M. Garnavich, P. Challis

Based on new CCD photometry and spectroscopy we confirm the presence of two cataclysmic variables (CVs) in the very old open cluster NGC 6791. One of these variables, known as B8, was observed by Rucinski, Kaluzny & Hilditch (1996) to undergo a large magnitude outburst in 1995. The spectrum of this star outside the outburst, obtained by us with MMT, shows cl

Kamiokande Collaboration, presented by J. G. Learned

The largest underground neutrino observatory, Super-Kamiokande, located near Kamioka, Japan has been collecting data since April 1996. It is located at a depth of roughly 2.7 kmwe in a zinc mine under a mountain, and has an effective area for detecting entering-stopping and through-going muons of about $1238 m^2$ for muons of $>1.7 GeV$. These events are col

John E. Gizis, I. Neill Reid

We present moderate resolution spectroscopy of 112 cool dwarf stars to supplement the observations we have already presented in the Palomar/MSU Nearby-Star Spectroscopic Survey. The sample consists of 72 suspected nearby stars added to the The Preliminary Third Catalog of Nearby Stars since 1991 as well as 40 faint red stars selected from the LHS catalog. LH

Ori J. Ganor, Rajesh Gopakumar, Sanjaye Ramgoolam

Scattering of zero branes off the fixed point in $R^8/Z_2$, as described by a super-quantum mechanics with eight supercharges, displays some novel effects relevant to Matrix theory in non-compact backgrounds. The leading long distance behaviour of the moduli space metric receives no correction at one loop in Matrix theory, but does receive a correction at tw

R. M. Green

We introduce an analogue of the $q$-Schur algebra associated to Coxeter systems of type $\hat A_{n-1}$. We give two constructions of this algebra. The first construction realizes the algebra as a certain endomorphism algebra arising from an affine Hecke algebra of type $\hat A_{r-1}$, where $n \geq r$. This generalizes the original $q$-Schur algebra as defin

Anupam Singh, Mark Srednicki

We present a general statistical analysis of Gamma Ray Bursts embedded in a host population. If no host generates more than one observed burst, then we show that there is a model independent lower bound on the number of hosts, $H$, of the form $H > c B^2$, where B is the number of observed bursts, and $c$ is a constant of order one which depends on the confi

A. Datta, K. Whisnant, Bing-Lin Young, X. Zhang

In terms of an effective lagrangian, we examine the effect of new physics associated with third-generation fermions on b b-bar production at the Z resonance and study its implications for LEP2. We obtain the constraints on such operators with derivative couplings at LEP1 and the SLC, and determine the prospects for detecting their presence at LEP2. We find t

B. M. Terhal, J. A. Smolin

We present a class of fast quantum algorithms, based on Bernstein and Vazirani&#39;s parity problem, that retrieve the entire contents of a quantum database $Y$ in a single query. The class includes binary search problems and coin-weighing problems. Our methods far exceed the efficiency of classical algorithms which are bounded by the classical information-t

A. C. Quillen, V. L. Sarajedini

We consider seven distant galaxies with clearly evident spiral structure from HST images. Three of these were chosen from Vogt et al. (1996) (VFP) and have measured rotational velocities. Five were chosen from the Medium Deep Survey and are studied in Sarajedini et al. 1996 (SGGR), and one galaxy is found in both papers. We place upper limits on their mass-t

Imran Shah, Steven Thomas

We consider the role of supersymmetry breaking soft terms that are present in generalized Narain compactifications of heterotic string theory, in which local supersymmetry is spontaneously broken, with gravitino masses being inversely proportional to the radii of compact dimensions. Such compactifications and their variants, are thought to be the natural app

Borge Nodland, John P. Ralston

Eisenstein and Bunn have widely circulated a Comment (astro-ph/9704247) suggesting a non-standard null hypothesis in a test for cosmological birefringence. The Comment misrepresents the procedure used by Nodland and Ralston (B. Nodland and J. P. Ralston, Phys. Rev. Lett. 78, 3043 (1997); astro-ph/9704196) and lacks statistical basis; no calculations were rep