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January 2003 arXiv papers — page 7

Showing 601–700 of 2,887 papers

  1. Tonghai Yang

    In this paper, we associate canonically to every imaginary quadratic field $K=\Bbb Q(\sqrt{-D})$ one or two isogenous classes of CM abelian varieties over $K$, depending on whether $D$ is odd or even ($D \ne 4$). These abelian varieties are characterized as of smallest dimension and smallest conductor, and such that the abelian varieties themselves descend t

  2. Florin Ambro

    We reduce the Abundance Conjecture in dimension 4 to the following numerical statement: if the canonical divisor K is nef and has maximal nef dimension, then K is big. From this point of view, we ``classify'' in dimension 2 nef divisors which have maximal nef dimension, but which are not big.

  3. J. S. Milne

    Assuming the Hodge conjecture for abelian varieties of CM-type, one obtains a good category of abelian motives over the algebraic closure of a finite field and a reduction functor to it from the category of CM-motives. Consequentely, one obtains a morphism of gerbes of fibre functors with certain properties. We prove unconditionally that there exists a morph

  4. Annette A'Campo-Neuen

    In a previous article, we proved tight lower bounds for the coefficients of the generalized $h$-vector of a centrally symmetric rational polytope using intersection cohomology of the associated projective toric variety. Here we present a new proof based on the theory of combinatorial intersection cohomology developed by Barthel, Brasselet, Fieseler and Kaup.

  5. Mu-Tao Wang

    We solve the Cauchy-Dirichlet problem for the minimal surface system in arbitrary dimension and codimension assuming a condition on the variation of the initial submanifold .

  6. Jae Choon Cha, Charles Livingston

    To each unit complex number with positive imaginary part there is defined a Tristram-Levine knot signature function. The set of all such signature functions is linearly independent as a set of functions defined on the set of all knots. The set of averaged signature functions forms a linearly independent set of homomorophisms on the knot concordance group. Ho

  7. Ya. I. Azimov

    Influence of the isospin-violating (ρ^0, ω)-mixing is discussed for any pair of decays of ρ^0, ωinto the same final state. It is demonstrated, in analogy to the CP-violation in neutral kaon decays, that isospin violation can manifest itself in various forms: direct violation in amplitudes and/or violation due to mixing. In addition to the known decays (ρ^0,

  8. A. V. Luchinsky

    Recent measurements of the Belle Collaboration of the exclusive production of two charmonia in the $e^+e^-$ annihilation differ substantially from theoretical predictions. Recently it was suggested that a significant part of this discrepancy can be explained by the process $e^2e^- --> 2J/psi$ and value for its cross-section was published. In this paper it is

  9. Qingguo Zheng, Ke Xu, Shilong Ma

    In this paper, we first define a difference measure between the old and new sequential patterns of stream data, which is proved to be a distance. Then we propose an experimental method, called TPD (Tradeoff between Performance and Difference), to decide when to update the sequential patterns of stream data by making a tradeoff between the performance of incr

  10. Dmitri A. Bagrets, Yuli V. Nazarov

    The review is given of the calculational schemes that allows for easy evaluation of full current statistics (FCS) in multi-terminal mesoscopic systems. First, the scattering approach by Levitov {\it et.al} to FCS is outlined. Then the multi-terminal FCS of the non-interacting electrons is considered. We show, that this theory appears to be a circuit theory o

  11. Daniel ben-Avraham, Alejandro F. Rozenfeld, Reuven Cohen, Shlomo Havlin

    A method for embedding graphs in Euclidean space is suggested. The method connects nodes to their geographically closest neighbors and economizes on the total physical length of links. The topological and geometrical properties of scale-free networks embedded by the suggested algorithm are studied both analytically and through simulations. Our findings indic

  12. Elisheva Cohen, David A. Kessler

    We investigate the equilibrium state of the model of Peng, \textit{et al.} for molecular breeding. In the model, a population of DNA sequences is successively culled by removing the sequences with the lowest binding affinity to a particular target sequence. The remaining sequences are then amplified to restore the original population size, undergoing some de

  13. S. De Rijcke, H. Dejonghe, W. W. Zeilinger, G. K. T. Hau

    We present photometric and kinematic evidence for the presence of stellar disks, seen practically edge-on, in two Fornax dwarf galaxies, FCC204 (dS0(6)) and FCC288 (dS0(7)). This is the first time such structures have been identified in Fornax dwarfs. FCC2088 has only a small bulge and a bright flaring and slightly warped disk that can be traced out to 23&#3

  14. F. K. Sutaria, A. Ray, A. Reisenegger, G. Hertling

    We report on deep VLT observations of the fields of two nearby, isolated millisecond pulsars PSR J1744-1134 and PSR J1024-0719. Both objects are old neutron stars with characteristic age $τ\ge 10^9$ yr and have relatively high spin-down flux. They have been detected earlier as X-ray sources by ROSAT HRI observations and were considered good candidates for no

  15. K. Dosen

    The monoids of simplicial endomorphisms, i.e. the monoids of endomorphisms in the simplicial category, are submonoids of monoids one finds in Temperley-Lieb algebras, and as the monoids of Temperley-Lieb algebras are linked to situations where an endofunctor is adjoint to itself, so the monoids of simplicial endomorphisms are linked to arbitrary adjoint situ

  16. K. A. Bronnikov, S. B. Fadeev, A. V. Michtchenko

    In the brane-world framework, we consider static, spherically symmetric configurations of a scalar field with the Lagrangian $(\dϕ)^2/2 - V(ϕ)$, confined on the brane. We use the 4D Einstein equations on the brane obtained by Shiromizu et al., containing the usual stress tensor $T\mN$, the tensor $Π\mN$, quadratic in $T\mN$, and $E\mN$ describing interaction

  17. J. M. Fregeau, M. A. Gurkan, K. J. Joshi, F. A. Rasio

    We study the dynamical evolution of globular clusters using our 2D Monte Carlo code with the inclusion of primordial binary interactions for equal-mass stars. We use approximate analytical cross sections for energy generation from binary-binary and binary-single interactions. After a brief period of slight contraction or expansion of the core over the first

  18. Sergei Fedotov

    Our attention focuses on the stochastic dynamo equation with non-normal operator that give an insight into the role of stochastics and non-normality in the galactic magnetic field generation. The main point of this Letter is a discussion of the generation of a large-scale magnetic field that cannot be explained by traditional linear eigenvalue analysis. We p

  19. Aristides Katavolos, Vern I. Paulsen

    We develop a symbol calculus for normal bimodule maps over a masa that is the natural analogue of the Schur product theory. Using this calculus we are able to easily give a complete description of the ranges of contractive normal bimodule idempotents that avoids the theory of J*-algebras. We prove that if $P$ is a normal bimodule idempotent and $\|P\| < 2/\s

  20. J. Hove, A. Sudbo

    Using Monte Carlo simulations we have studied the $d=3$ $Z_q$ clock model in two different representations, the phase-representation and the loop/dumbbell-gas (LDG) representation. We find that for $q \ge 5$ the critical exponents $α$ and $ν$ for the specific heat and the correlation length, respectively, take on values corresponding to the case $q\to \infty

  21. Changhyun Ahn, Soonkeon Nam

    We use the matrix model to describe the N=2 SO(N)/Sp(N) supersymmetric gauge theories with massive hypermultiplets in the fundamental representation. By taking the tree level superpotential perturbation made of a polynomial of a scalar chiral multiplet, the effective action for the eigenvalues of chiral multiplet can be obtained. By varying this action with

  22. Ulf-G. Meißner, Véronique Bernard, Evgeny Epelbaum, Walter Glöckle

    Some recent developments in the description of nuclear forces and few-nucleon dynamics derived from chiral effective field theory are reviewed.

  23. P. G. Kevrekidis, Boris A. Malomed, D. J. Frantzeskakis, A. R. Bishop

    We introduce domain-wall (DW) states in the bimodal discrete nonlinear Schr{ö}dinger equation, in which the modes are coupled by cross phase modulation (XPM). By means of continuation from various initial patterns taken in the anti-continuum (AC) limit, we find a number of different solutions of the DW type, for which different stability scenarios are identi

  24. S. V. Kozyrev

    We define dynamical systems where time is a quantum group. We give the definition of quantum ergodicity for the introduced dynamical system with noncommutative (or quantum) time, and discuss the examples.

  25. Christos E. Frouzakis, Ioannis G. Kevrekidis, Bruce B. Peckham

    In a one-parameter study of a noninvertible family of maps of the plane arising in the context of a numerical integration scheme, Lorenz studied a sequence of transitions from an attracting fixed point to &#34;computational chaos.&#34; As part of the transition sequence, he proposed the following as a possible scenario for the breakup of an invariant circle:

  26. Emanuele Caglioti, Francois Golse

    In a flat 2-torus with a disk of diameter $r$ removed, let $Φ_r(t)$ be the distribution of free-path lengths (the probability that a segment of length larger than $t$ with uniformly distributed origin and direction does not meet the disk). We prove that $Φ_r(t/r)$ behaves like $\frac{2}{π^2 t}$ for each $t>2$ and in the limit as $r\to 0^+$, in some appropria

  27. Yves Laurent

    The invariant eigendistributions on a reductive Lie algebra are solutions of a holonomic D-module which has been proved to be regular by Kashiwara-Hotta. We solve here a conjecture of Sekiguchi saying that in the more general case of symmetric pairs, the corresponding module are still regular.

  28. Jens Gerlach Christensen

    For unbounded operators A,B and C in general, with C closure of [A,B] does not lead to the uncertainty relation ||Au|| ||Bu|| >= |<C u,u> |/2. If A,B and C are part of the generators of a unitary representation of a Lie group then the uncertainty principle above holds.

  29. S. Hunzinger, M. Mattes, M. Sorg

    Within the framework of Relativistic Schroedinger Theory (an alternative form of quantum mechanics for relativistic many-particle systems) it is shown that a general N-particle system must occur in one of two forms: either as a ``positive&#39;&#39; or as a ``negative&#39;&#39; mixture, in analogy to the fermion-boson dichotomy of matter in the conventional t

  30. M. R. Setare

    The Casimir forces on two parallel plates in conformally flat de Sitter background due to conformally coupled massless scalar field satisfying mixed boundary conditions on the plates is investigated. In the general case of mixed boundary conditions formulae are derived for the vacuum expectation values of the energy-momentum tensor and vacuum forces acting o

  31. Don Colladay

    In this talk, I discuss some recent theoretical progress concerning the Lorentz- and CPT-violating extension of the standard model. The results summarized include the development of an explicit connection between noncommutative field theory and the standard model extension, placement of new bounds in the photon sector, calculation of one-loop renormalization

  32. A. G. Yaneff

    Bounds for the optimal tour length for a hypothetical TSP algorithm are derived.

  33. A. G. Yaneff

    Withdrawn. Silly notion and out of context.

  34. Oleksiy Svitelskiy, Jean Toulouse, Z. -G. Ye

    Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_{3}$ is one of the simplest representatives of the class of lead relaxors and often serves as a model system for more complicated compounds. In this paper we analyse both polarized and depolarized Raman scattering spectra, measured in the temperature range between 1000 and 100 K, by multiple peak decomposition. Basing on this analy

  35. J. Hove, A. Sudbo

    Paper has been withdrawn, see comment.

  36. R. Fleysher

    The majority of galactic gamma rays are produced by interaction of cosmic rays with matter or radiation fields. This results in a diffuse radiation concentrated in the galactic plane where the flux of cosmic rays and the density of material (mostly atomic, molecular and ionized hydrogen) is high. The interactions producing gamma rays include, among others, t

  37. M. A. Barstow, S. A. good, J. B. Holberg, I. Hubeny

    We present a series of systematic abundance measurements for 25 hot DA white dwarfs in the temperature range ~20000-110000K, based on far-UV spectroscopy with STIS/GHRS on HST, IUE and FUSE. Using our latest heavy element blanketed non-LTE stellar atmosphere calculations we have addressed the heavy element abundance patterns making completely objective measu

  38. Ewine F. van Dishoeck

    Recent observational studies of high- and low-mass YSOs at (sub)millimeter and infrared wavelengths are reviewed, and chemical diagnostics of the different physical components are summarized. Methods for determining the temperature, density and abundance profiles in the envelopes are outlined, and are illustrated for one high-mass and one low-mass YSO. The c

  39. Sujan Sengupta

    Recent observation of linear optical polarization from brown dwarfs confirms the dust hypothesis in the atmospheres of brown dwarfs with effective temperature higher than 1400 K. The observed polarization could arise due to dust scattering in the rotation induced oblate photosphere or due to the scattering by non-spherical grains in the spherical atmosphere

  40. Aya Bamba, Masaru Ueno, Katsuji Koyama, Shigeo Yamauchi

    We found diffuse hard X-ray sources, G11.0+0.0, G25.5+0.0, and G26.6-0.1 in the ASCA Galactic plane survey data. The X-ray spectra are featureless with no emission line, and are fitted with both models of a thin thermal plasma in non-equilibrium ionization and a power-law function. The source distances are estimated to be 1-8 kpc, using the best-fit NH value

  41. Masaru Ueno, Aya Bamba, Katsuji Koyama, Ken Ebisawa

    We present the Chandra results of AX J1843.8-0352, a supernova remnant (SNR) recently identified with ASCA. Chandra spatially resolved two components from this SNR: non-thermal and thermal ones. The morphology of the non-thermal component is clumpy and elliptical, elongated from the north to the south with a mean diameter of about 9 arcmin. The spectrum is f

  42. Christopher R. Burns, Christopher Tycner, Megan McClure, Kris Blindert

    We present a detailed analysis of the distance determination for one intermediate Velocity Cloud (IVC G139.6+47.6) from the ongoing DDO IVC Distance Project. Stars along the line of sight to G139.6+47.6 are examined for the presence of sodium absorption attributable to the cloud, and the distance bracket is established by astrometric and spectroscopic parall

  43. J. M. Bai, Myung Gyoon Lee

    In the internal shock scenario, we argue that electrons in most kpc (or even larger) scale jets can be accelerated to energies high enough to emit synchrotron X-rays, if shocks exist on these scales. These high energy electrons emit synchrotron radiation at high frequencies and cool as they propagate downstream along the jet, emitting at progressively lower

  44. Lihong Yao, E. R. Seaquist, Nario Kuno, Loretta Dunne

    We present the first statistical survey of the properties of the 12CO(1-0) and 12CO(3-2) line emission from the nuclei of a nearly complete subsample of 60 infrared (IR) luminous galaxies selected from SCUBA Local Universe Galaxy Survey (SLUGS). This subsample is flux limited at S60 mincron > 5.24 Jy with far-IR (FIR) luminosities mostly at LFIR > 10^10 LSUN

  45. Gia Dvali, Michael S. Turner

    Dark energy could actually be the manifestation of a modification to the Friedmann equation arising from new physics (e.g., extra dimensions). Writing the correction as $(1-Ω_M)H^α/H_0^{α-2}$, we explore the phenomenology and detectability of such. We show that: (i) $α$ must be $\la 1$; (ii) such a correction behaves like dark energy with equation-of-state $

  46. Charles F. Gammie, Jonathan C. McKinney, Gábor Tóth

    We describe a conservative, shock-capturing scheme for evolving the equations of general relativistic magnetohydrodynamics. The fluxes are calculated using the Harten, Lax, and van Leer scheme. A variant of constrained transport, proposed earlier by Tóth, is used to maintain a divergence free magnetic field. Only the covariant form of the metric in a coordin

  47. Keith A. Olive

    Observational evidence and theoretical motivation for dark matter are presented and connections to the CMB and BBN are made. Problems for baryonic and neutrino dark matter are summarized. Emphasis is placed on the prospects for supersymmetric dark matter.

  48. Mikkel B. Johnson, Ho-Meoyng Choi, Leonard S. Kisslinger

    Starting from the QCD action in an instanton-like SU(2) Yang-Mills field theory, we derive equations of motion in Minkowski space. Possible bubble collisions are studued in a (1+1)-dimension reduction . We find gluonic structures like interior walls, which might give rise to CMBR effects.

  49. Jason Metcalfe, Christopher D. Sogge

    We prove global existence for quasilinear wave equations outside of a wide class of obstacles. The obstacles may contain trapped hyperbolic rays as long as there is local exponential energy decay for the associated linear wave equation. Thus, we can handle all non-trapping obstacles. We are also able to handle non-diagonal systems satisfying the appropriate

  50. Manuel Calixto

    We study a new class of infinite-dimensional Lie algebras W_\infty(p,q) generalizing the standard W_\infty algebra, viewed as a tensor operator algebra of SU(1,1) in a group-theoretic framework. Here we interpret W_\infty(p,q) either as an infinite continuation of the pseudo-unitary symmetry U(p,q), or as a &#34;higher-U(p,q)-spin extension&#34; of the diffe

  51. Regina Karle, Jiannis Pachos

    We generalize the usual abelian Berry phase generated for example in a system with two non-degenerate states to the case of a system with two doubly degenerate energy eigenspaces. The parametric manifold describing the space of states of the first case is formally given by the G(2,1) Grassmannian manifold, while for the generalized system it is given by the

  52. Zhenjun Xiao, Cai-Dian Lü, Wujun Huo

    Within the framework of the Top-color-assisted Technicolor (TC2) model, we calculate the new physics contributions to the branching ratios $\calb(B_{s,d} \to γγ)$ and CP violating asymmetries $\rcpm(B_{s,d} \to γγ)$ in the QCD factorization based on the heavy-quark limit $m_b \gg Λ_{QCD}$. Using the considered parameter space, we find that (a) for both $B_s\

  53. Pavlos Pasipoularides

    In Ref. 3, we presented an asymptotic formula for the fermion-induced effective energy in 3+1 dimensions in the presence of a cylindrically symmetric inhomogeneous strong magnetic field. However, there are some points which were not clearly explained. In fact, the arguments, which led us to the asymptotic formula, are based on a numerical study of the integr

  54. A. Mironov

    This brief review deals with prepotentials inspired by N=1 SUSY considerations due to Cachazo, Intrilligator, Vafa. These prepotentials associated with matrix models following Dijkgraaf and Vafa should be considered as given on an enlarged moduli space that includes Whitham times (couplings of the superpotential). This moduli space is nothing but the whole m

  55. Banibrata Mukhopadhyay, Naresh Dadhich

    We study the scalar and spinor perturbation, namely the Klein-Gordan and Dirac equations, in the Kerr-NUT space-time. The metric is invariant under the duality transformation involving the exchange of mass and NUT parameters on one hand and radial and angle coordinates on the other. We show that this invariance is also shared by the scalar and spinor perturb

  56. C. Cartier, R. Durrer, E. J. Copeland

    We investigate both analytically and numerically the evolution of scalar perturbations generated in models which exhibit a smooth transition from a contracting to an expanding Friedmann universe. We find that the resulting spectral index in the late radiation dominated universe depends on which of the $Ψ$ or \$zeta$ variables passes regularly through the tra

  57. Yuriy Mishchenko, Chueng-Ryong Ji

    We study the distribution of dark matter versus visible matter using a set of data obtained from strong gravitational lensing in the galaxy cluster CL0024+1654 and another set of data inferred from the universal rotation curves in spiral galaxies. The important feature of these two dramatically different observations is that the mass density profile of both

  58. E. Courtens, M. Foret, B. Hehlen, B. Ruffle

    Spectroscopic results on low frequency excitations of densified silica are presented and related to characteristic thermal properties of glasses. The end of the longitudinal acoustic branch is marked by a rapid increase of the Brillouin linewidth with the scattering vector. This rapid growth saturates at a crossover frequency Omega_co which nearly coincides

  59. Steen Ryom-Hansen

    We deal with the representation theory of quantum groups and Hecke algebras at roots of unity. We relate the philosophy of Andersen, Jantzen and Soergel on graded translated functors to the Lascoux, Leclerc and Thibon-algorithm. This goes via the Murphy standard basis theory and the idempotents coming from the Murphy-Jucys operators. Our results lead to a gu

  60. M. Cosentino Lagomarsino, P. Jona, B. Bassetti

    We employ a model system, called rowers, as a generic physical framework to define the problem of the coordinated motion of cilia (the metachronal wave) as a far from equilibrium process. Rowers are active (two-state) oscillators interacting solely through forces of hydrodynamic origin. In this work, we consider the case of fully deterministic dynamics, find

  61. A. Sandoval-Villalbazo, L. S. Garcia-Colin

    This paper shows that the ordinary Brillouin spectrum peaks associated to scattered radiation off acoustic modes in a fluid suffer a shift in their values due to gravitational effects. The approach is based in the ordinary linearized Navier-Stokes equations for a fluid coupled to a Newtonian gravitational potential. The formalism leads to a dispersion relati

  62. Jan Pisut, Neva Pisutova, Boris Tomasik

    We present a few estimates of energy densities reached in heavy-ion collisions at the CERN SPS. The estimates are based on data and models of proton-nucleus and nucleus-nucleus interactions. In all of these estimates the maximum energy density in central Pb+Pb interactions is larger than the critical energy density of about 0.7 GeV/fm^3 following from lattic

  63. Milan Krbalek, Dirk Helbing

    Many-particle simulations of vehicle interactions have been quite successful in the qualitative reproduction of observed traffic patterns. However, the assumed interactions could not be measured, as human interactions are hard to quantify compared to interactions in physical and chemical systems. We show that progress can be made by generalizing a method fro

  64. Vincent Guirardel

    The deformation space of a simplicial G-tree T is the set of G-trees which can be obtained from T by some collapse and expansion moves, or equivalently, which have the same elliptic subgroups as T. We give a short proof of a rigidity result by Forester which gives a sufficient condition for a deformation space to contain an Aut(G)-invariant G-tree. This give

  65. Kui-Yong Liu, Zhi-Guo He, Kuang-Ta Chao

    Motivated by the recent observation of double charm quark pair production by the Belle Collaboration, we calculate the complete ${\cal O}(α_{s}^{2})$ inclusive production cross sections for $η_{c}$, $J/ψ$, and $χ_{cJ}$(J=0, 1, 2) plus $c\bar{c}$ in $e^+ e^-$ annihilation through a virtual photon. We consider both color-singlet and color-octet contributions,

  66. Hiroto Kuninaka, Hisao Hayakawa

    The oblique collision between an elastic disk and an elastic wall is numerically studied. We investigate the dependency of the tangential coefficient of restitution on the incident angle of impact. From the results of simulation, our model reproduces experimental results and can be explained by a phenomenological theory of the oblique impact.

  67. ALEPH Collaboration, Arno Heister

    The inclusive production of D$^{*\pm}$ mesons in two-photon collisions is measured with the ALEPH detector at $\epem$ centre-of-mass energies from 183$\unit{GeV}$ to 209$\unit{GeV}$. A total of $360 \pm 27$ D$^{*\pm}$ meson events were observed from an integrated luminosity of 699\unit{pb^{-1}}$. Contributions from direct and single-resolved rocesses are sep

  68. S. I. Agafonov, A. I. Bobenko

    Hexagonal circle patterns with constant intersection angles mimicking holomorphic maps z^c and log(z) are studied. It is shown that the corresponding circle patterns are immersed and described by special separatrix solutions of discrete Painleve and Riccati equations. The general solution of the Riccati equation is expressed in terms of the hypergeometric fu

  69. Sumiyoshi Abe

    Nonadditive (nonextensive) generalization of the quantum Kullback-Leibler divergence, termed the quantum q-divergence, is shown not to increase by projective measurements in an elementary manner.

  70. Daniel De Marco, Pasquale Blasi, Angela V. Olinto

    The nature of the unknown sources of ultra-high energy cosmic rays can be revealed through the detection of the GZK feature in the cosmic ray spectrum, resulting from the production of pions by ultra-high energy protons scattering off the cosmic microwave background. Here we show that the GZK feature cannot be accurately determined with the small sample of e

  71. Hans Ringstrom

    Bianchi VIII vacuum solutions to Einstein&#39;s equations are causally geodesically complete to the future, given an appropriate time orientation, and the objective of this article is to analyze the asymptotic behaviour of solutions in this time direction. For the Bianchi class A spacetimes, there is a formulation of the field equations that was presented in

  72. P. Limelette, P. Wzietek, S. Florens, A. Georges

    We have performed in-plane transport measurements on the two-dimensional organic salt $κ$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Cl. A variable (gas) pressure technique allows for a detailed study of the changes in conductivity through the insulator-to-metal transition. We identify four different transport regimes as a function of pressure and temperature (correspon

  73. V. A. De Lorenci, E. S. Moreira,

    The renormalized Feynman propagator for a scalar field in the background of a cosmic dispiration (a disclination plus a screw dislocation) is derived, opening a window to investigate vacuum polarization effects around a cosmic string with dislocation, as well as in the bulk of an elastic solid carrying a dispiration. The use of the propagator is illustrated

  74. Simone Calogero

    The kinetic motion of the stars of a galaxy is considered within the framework of a relativistic scalar theory of gravitation. This model, even though unphysical, may represent a good laboratory where to study in a rigorous, mathematical way those problems, like the influence of the gravitational radiation on the dynamics, which are still beyond our present

  75. W. J. G. de Blok, F. Walter

    We present wide-field optical imaging covering the entire neutral hydrogen disc of the Local Group dwarf galaxy NGC 6822. These observations reveal the presence of numerous blue, young stars at large galactocentric radii well beyond R_25. Blue stars are also found that are associated with NGC 6822&#39;s companion HI cloud, indicating that star formation was

  76. Ivar Ekeland, Erik Taflin

    We introduce a bond portfolio management theory based on foundations similar to those of stock portfolio management. A general continuous-time zero-coupon market is considered. The problem of optimal portfolios of zero-coupon bonds is solved for general utility functions, under a condition of no-arbitrage in the zero-coupon market. A mutual fund theorem is p

  77. M. Osipenko, G. Ricco, M. Taiuti, M. Anghinolfi

    Unique measurement of the proton structure function F2 in a wide two-dimensional region of x and Q**2 has been reported. The accessible kinematics covers entire resonance region up to W=2.5 GeV in the Q**2 interval from 0.1 to 4.5 GeV**2. Obtained data allowed for the first time an evaluation of moments of the structure function F2 directly from experimental

  78. Mun Dae Kim, Dongkwan Shin, Jongbae Hong

    The effective potentials of the rf-SQUID and three-Josephson junction loop with a penetrating external magnetic flux are studied. Using the periodic boundary condition for the phase evolution of the wave function of Cooper pairs, we obtain new periodic potentials with cusp barriers in contrast with the usual smooth double-well potential. The tunneling throug

  79. Jian-Qi Shen

    The physically interesting gravitational analogue of magnetic monopole in electrodynamics is considered in the present paper. The author investigates the field equation of gravitomagnetic matter, and the exact static cylindrically symmetric solution of field equation as well as the motion of gravitomagnetic charge in gravitational fields. Use is made of the

  80. Haruki Kurasawa, Toshio Suzuki, Nguyen Van Giai

    The issue of Gamow-Teller sum rule in atomic nuclei is reexamined in the framework of a relativistic description of nuclei. It is shown that the total Gamow-Teller strength in the nucleon sector is reduced by about 12% as compared to the prediction of a non-relativistic description. This reduction is due to the antinucleon degrees of freedom.

  81. Jack Gegenberg, Cristian Martinez, Ricardo Troncoso

    Three-dimensional gravity with a minimally coupled self-interacting scalar is considered. The fall-off of the fields at infinity is assumed to be slower than that of a localized distribution of matter, so that the asymptotic symmetry group is the conformal group. The counterterm Lagrangian needed to render the action finite is found by demanding that the act

  82. Belle Collaboration, K. Abe

    We present an improved measurement of CP-violating asymmetries in B0 -> pi+ pi- decays based on a 78 fb^-1 data sample collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We reconstruct one neutral B meson as a B0 -> pi+ pi- CP eigenstate and identify the flavor of the accompanying B meson from inclusive prop

  83. Andrew R. Frey

    We consider warped compactifications that solve the 10 dimensional supergravity equations of motion at a point, stabilize the position of a D3-brane world, and admit a warp factor that violates Lorentz invariance along the brane. This gives a string embedding of ``asymmetrically warped&#39;&#39; models which we use to calculate stringy (α&#39;) corrections t

  84. Alexey E. Rastegin

    By relevant modifications, the known global-fidelity limits of state-dependent cloning are extended to mixed quantum states. We assume that the ancilla contains some a priori information about the input state. As it is shown, the obtained results contribute to the stronger no-cloning theorem. An attainability of presented limits is discussed.

  85. Francois-Regis Carminati, Laurent Sanchez-Palencia, Michele Schiavoni, Ferruccio Renzoni

    We investigate Rayleigh scattering in dissipative optical lattices. In particular, following recent proposals (S. Guibal {\it et al}, Phys. Rev. Lett. {\bf 78}, 4709 (1997); C. Jurczak {\it et al}, Phys. Rev. Lett. {\bf 77}, 1727 (1996)), we study whether the Rayleigh resonance originates from the diffraction on a density grating, and is therefore a probe of

  86. Sumiyoshi Abe

    The Kullback-Leibler divergence offers an information-theoretic basis for measuring the difference between two given distributions. Its quantum analog, however, fails to play a corresponding role for comparing two density matrices, if the reference states are pure states. Here, it is shown that nonadditive (nonextensive) generalization of quantum information

  87. Esben Skovsen, Henrik Stapelfeldt, Soren Juhl, Klaus Molmer

    Using tomographic reconstruction we determine the complete internuclear quantum state, represented by the Wigner function, of a dissociating I2 molecule based on femtosecond time resolved position and momentum distributions of the atomic fragments. The experimental data are recorded by timed ionization of the photofragments with an intense 20 fs laser pulse.

  88. Solvejg Jorgensen, Ronnie Kosloff

    A spectroscopic application of the atom laser is suggested. The spectroscopy termed 2PACC employs the coherent properties of matter-waves from a two pulse atom laser. These waves are employed to control a gas-surface chemical recombination reaction. The method is demonstrated for an Eley-Rideal reaction of a hydrogen or alkali atom-laser pulse where the surf

  89. Pankaj Sharan, Pravabati Chingangbam

    We recast Dirac&#39;s Lagrangian in quantum mechanics in the language of vector bundles and show that the action is an operator-valued connection one-form. Phases associated with change of frames of reference are seen to be total differentials in the transformation of the action. The relativistic case is discussed and we show that it gives the correct phase

  90. W. LiMing, Z. L. Tang, C. Liao

    Cabello proved Bell&#39;s theorem without using inequalities. A loophole of Cabello&#39;s proof is pointed out in this work.

  91. Z. Xiong, N. C. Bacalis

    We propose simple analytic, non-orthogonal but selectively orthogonalizable, generalized Laguerre type atomic orbitals, providing clear physical interpretation and near equivalent accuracy with numerical multi-configuration self-consistent field, to atomic configuration interaction calculations. By analyzing the general Eckart theorem we use their simple int

  92. Swapan Roychowdhury, Biman Bagchi

    Vibrational dephasing of nitrogen molecule is known to show highly interesting anomalies near its gas-liquid critical point. Here we present theoretical and computational studies of the Raman linewidth of nitrogen along the critical isochore. The linewidth is found to have a lambda shaped temperature dependence near the critical point. As observed in experim

  93. K. Tsushima, D. H. Lu, W. Melnitchouk, K. Saito

    We discuss the electromagnetic form factors, axial form factors, and structure functions of a bound nucleon in the quark-meson coupling (QMC) model. Free space nucleon form factors are calculated using the improved cloudy bag model (ICBM). After describing finite nuclei and nuclear matter in the quark-based QMC model, we compute the in-medium modification of

  94. C. Hillhouse, J. Mano, A. A. Cowley, R. Neveling

    Within the framework of the relativistic distorted wave impulse approximation (DWIA), we investigate the sensitivity of the analyzing power - for exclusive proton knockout from the 3s$_{1/2}$, 2d$_{3/2}$ and 2d$_{5/2}$ states in $^{208}$Pb, at an incident laboratory kinetic energy of 202 MeV, and for coincident coplanar scattering angles ($28.0^{\circ}$, $-5

  95. STAR Collaboration

    The balance function is a new observable based on the principle that charge is locally conserved when particles are pair produced. Balance functions have been measured for charged particle pairs and identified charged pion pairs in Au+Au collisions at $\sqrt{s_{NN}}$ = 130 GeV at the Relativistic Heavy Ion Collider using STAR. Balance functions for periphera

  96. Thomas Wolf

    Work on different classification problems is described as: the classification of integrable vector evolution equations, NLS systems with two vector unknowns, systems with one scalar and one vector unknown, classification of integrable Hamiltonians and non-local 2+1 dimensional equations. All these problems lead to large bi-linear algebraic systems to be solv

  97. David R. Bickel

    Three aspects of time series are uncertainty (dispersion at a given time scale), scaling (time-scale dependence), and intermittency (inclination to change dynamics). Simple measures of dispersion are the mean absolute deviation and the standard deviation; scaling exponents describe how dispersions change with the time scale. Intermittency has been defined as

  98. Mark Goresky, Robert MacPherson

    This note contains a correction to the paper, ``Local contribution to the Lefschetz fixed point formula&#39;&#39;, Inv. Math. 111 (1993), pp. 1-33.

  99. Razvan Gelca, Jeremy Sain

    The paper contains the computation of the noncommutative A-ideal of the figure-eight knot, a noncommutative generalization of the A-polynomial. We show that if a knot has the same noncommutative A-ideal as the figure-eight knot, then all colored Kauffman brackets are the same as those of the figure-eight knot.

  100. Steen Ryom-Hansen

    We deduce the Schaper formula for Hecke-algebras at root of unity from the Jantzen conjecture in the LLT-setup. This explains an observation due to R. Rouquier.