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January 2003 arXiv papers — page 2

Showing 101–200 of 2,887 papers

  1. A. Caiazzo, A. Coniglio, M. Nicodemi

    We introduce a spherical version of the frustrated Blume-Emery-Griffiths model and solve exactly the statics and the Langevin dynamics for zero particle-particle coupling (K=0). In this case the model exhibits an equilibrium transition from a disordered to a spin glass phase which is always continuous for nonzero temperature. The same phase diagram results f

  2. R. Gutierrez, G. Fagas, K. Richter, F. Grossmann

    The conductance of a molecular junction is commonly determined by either charge-transfer-doping, where alignment of the Fermi energy to the molecular levels is achieved, or tunnelling through the tails of molecular resonances within the highest-occupied and lowest-unoccupied molecular-orbital gap. Here, we present an alternative mechanism where electron tran

  3. Parongama Sen, S. S. Manna

    Many real-world networks exhibit scale-free feature, have a small diameter and a high clustering tendency. We have studied the properties of a growing network, which has all these features, in which an incoming node is connected to its $i$th predecessor of degree $k_i$ with a link of length $\ell$ using a probability proportional to $k^β_i \ell^α$. For $α> -

  4. Masafumi Ito, Yukio Yasui, Satoshi Iikubo, Minoru Soda

    The wave vector(q)- and energy(w)-dependent magnetic excitation spectra c&#34;(q,w), have been studied in the temperature(T) range of 10 K<T<150 K on single crystals of La1.48Nd0.4Sr0.12CuO4, which has the static &#34;stripe&#34; order in the low temperature phase. The incommensurability d of the peak of c&#34;(q,w) found by the q-scans and the peak width Dq

  5. R. E. Cohen

    Using a first principles based, magnetic tight-binding total energy model, the magnetization energy and moments are computed for various ordered spin configurations in the high pressure polymorphs of iron (fcc, or $γ$-Fe, and hcp, or $ε$-Fe), as well ferromagnetic bcc iron ($α$-Fe). For hcp, a non-collinear, antiferromagnetic, spin configuration that minimiz

  6. H. Tsujii, R. C. Rotundu, B. Andraka, Y. Takano

    We characterize the field-induced magnetic phases of SrCu2(BO3)2, a frustrated spin-1/2 Heisenberg antiferromagnet in the two-dimensional Shastry-Sutherland lattice, using specific heat in magnetic fields up to 33 T. We find that the spin gap persists above the expected critical field Hc = Delta/g*mu_B of 21 T despite the appearance of magnetic moment in the

  7. A. D. Gopal, D. J. Durian

    We investigate the mechanical response of an aqueous foam, and its relation to the microscopic rearrangement dynamics of the bubble-packing structure. At rest, even though the foam is coarsening, the rheology is demonstrated to be linear. Under flow, shear-induced rearrangements compete with coarsening-induced rearrangements. The macroscopic consequences are

  8. Yosef Ashkenazy, Shlomo Havlin, Plamen Ch. Ivanov, Chung-K. Peng

    We study the correlation properties of long-range correlated time series, $x_i$, with tunable correlation exponent and built-in multifractal properties. For the cases we investigate we find that the correlation exponent of the magnitude series, $|x_{i+1}-x_i|$, is a monotonically increasing function of the multifractal spectrum width of the original series.

  9. S. G. Djorgovski, S. R. Kulkarni, D. A. Frail, F. A. Harrison

    Studies of the cosmic gamma-ray bursts (GRBs) and their host galaxies are starting to provide interesting or even unique new insights in observational cosmology. GRBs represent a new way of identifying a population of star-forming galaxies at cosmological redshifts. GRB hosts are broadly similar to the normal field galaxy populations at comparable redshifts

  10. David Blaschke, Danilo Behnke, Victor Pervushin, Denis Proskurin

    We show that in the units of the relative Paris meter both the latest data on the Supernova luminosity-distance -- redshift relation and primordial nucleosynthesis are described by the dynamics of a homogeneous, massless scalar field (Scalar Quintessence) in a nonexpanding universe.

  11. Andrew W. Stephens, Jay A. Frogel, D. L. DePoy, Wendy Freedman

    In this paper we analyze the stellar populations present in M31 using nine sets of adjacent HST-NICMOS Camera 1 and 2 fields with galactocentric distances ranging from 2&#39; to 20&#39;. These infrared observations provide some of the highest spatial resolution measurements of M31 to date; our data place tight constraints on the maximum luminosities of stars

  12. Xiaolei Zhang

    It is now a well established fact that galaxies undergo significant morphological transformation during their lifetimes, manifesting as an evolution along the Hubble sequence from the late to the early Hubble types. The physical processes commonly believed to be responsible for this observed evolution trend, i.e. the major and minor mergers, as well as gas a

  13. Klaus Schenker, Graham A. Wynn, Roland Speith

    We investigate the spin evolution of the unusual magnetic CV AE Aqr. As a prototype for a potentially large population of CVs subject to a thermally unstable phase of mass transfer, understanding its future is crucial. We present a new definition of the magnetospheric radius in terms of the white dwarf&#39;s spin period, and use this along with numerical sim

  14. A. D. Erlykin, A. W. Wolfendale

    The idea that the shocks from supernova remnants (SNR) expanding into the interstellar medium (ISM) accelerate CR is still popular one but a number of authors have drawn attention to the fact that the experimental evidence for the presence of gamma rays from the expected interaction of CR with gas in the remnant is poor. Indeed, it is claimed that many SNR a

  15. Curtis Struck, Beverly J. Smith

    (abridged) We present new N-body, hydrodynamical simulations of the interaction between the starburst galaxy NGC 7714 and its post-starburst companion NGC 7715, focusing on the formation of the collisional features, including: 1) the gas-rich star forming bridge, 2) the large gaseous loop (and stellar tails) to the west of the system, 3) the very extended HI

  16. Aurore Bacmann, Bertrand Lefloch, Cecilia Ceccarelli, Juergen Steinacker

    We report the detection of D2CO in a sample of starless dense cores, in which we previously measured the degree of CO depletion. The deuterium fractionation is found extremely high, [D2CO]/[H2CO] ~ 1-10 %, similar to that reported in low-mass protostars. This provides convincing evidence that D2CO is formed in the cold pre-stellar cores, and later desorbed w

  17. Yousaf M. Butt, Gustavo E. Romero, Diego F. Torres

    We suggest that ultraluminous X-ray sources (ULXs) and some of the variable low latitude EGRET gamma-ray sources may be two different manifestations of the same underlying phenomena: high-mass microquasars with relativistic jets forming a small angle with the line of sight (i.e. microblazars). Microblazars with jets formed by relatively cool plasma (Lorentz

  18. D. Dobrzycka, J. C. Raymond, D. A. Biesecker, J. Li

    We present Ultraviolet Coronagraph Spectrometer (UVCS) observations of 5 narrow coronal mass ejections (CMEs) that were among 15 narrow CMEs originally selected by Gilbert et al. (2001). Two events (1999 March 27, April 15) were &#34;structured&#34;, i.e. in white light data they exhibited well defined interior features, and three (1999 May 9, May 21, June 3

  19. D. Carollo, D. Koester, A. Spagna, M. G. Lattanzi

    A new model atmosphere analysis for the peculiar DQ white dwarf discovered by Carollo et al. (2002) is presented. The effective temperature and carbon abundance have been estimated by fitting both the photometric data (UBJ,VRF,IN,JHK) and a low resolution spectrum (3500<lambda<7500 A) with a new model grid for helium-rich white dwarfs with traces of carbon (

  20. Marc Balcells

    Recent progress on the structure and dynamics of bulges is reviewed. Those aspects that link galaxy bulges either to oblate spheroids akin to elliptical galaxies or to rapidly-rotating, flattened systems more nearly resembling the products of disk internal transformations, are highlighted. The analysis of surface brightness profiles derived from HST data is

  21. Eric M. Schlegel, Anandi Salinas

    We present a preliminary look at the serendipitous observation of the intermediate polar TX Col by Chandra. The 52 ksec observation is uninterrupted, providing an opportunity to disentangle the light curve and power spectra components. We illustrate the energy-dependence of the power spectrum.

  22. M. Giersz, R. Spurzem

    Spherically symmetric equal mass star clusters containing a large amount of primordial binaries are studied using a hybrid method, consisting of a gas dynamical model for single stars and a Monte Carlo treatment for relaxation of binaries and the setup of close resonant and fly-by encounters of single stars with binaries and binaries with each other (three-

  23. J. Holt, C. N. Tadhunter, R. Morganti

    We demonstrate the efficiency of high quality optical spectroscopic observations of two compact radio sources, PKS 1549-79 and PKS 1345+12, as a probe of the kinematics and physical conditions in the circumnuclear gas in the early stages of radio source evolution. We outline a schematic model for PKS 1345+12 based on the model for PKS 1549-79 proposed by Tad

  24. R. Mohayaee, U. Frisch, S. Matarrese, A. Sobolevskii

    A method for the reconstruction of the primordial density fluctuation field is presented. Various previous approaches to this problem rendered {\it non-unique} solutions. Here, it is demonstrated that the initial positions of dark matter fluid elements, under the hypothesis that their displacement is the gradient of a convex potential, can be reconstructed u

  25. Houri Ziaeepour

    It is a known fact that a quintessence model with $w_q < -1$ fits the publicly available Super Nova (SN) type Ia data better than a model with cosmological constant or $w_q > -1$. Two types of models have this property: Scalar fields with unconventional kinetic term and models with cosmological constant and a slowly decaying Cold Dark Matter (CDM). In this w

  26. K. Otmianowska-Mazur, B. Vollmer

    A fully three-dimensional (3D) magnetohydrodynamical (MHD) model is applied to simulate the evolution of the large-scale magnetic field in cluster galaxies interacting with the intra-cluster medium (ICM). As the model input we use a time dependent gas velocity field resulting from 3D N-body sticky-particle simulations of a galaxy. The modeled clouds are affe

  27. M. A. Gomez-Flechoso, D. Martinez-Delgado

    Dwarf satellite galaxies undergo strong tidal forces produced by the main galaxy potential. These forces disturb the satellite, producing asymmetries in its stellar distribution, tidal tail formation, and modifications of the velocity dispersions profiles. Most of these features are observed in the Ursa Minor (UMi) dwarf spheroidal galaxy, which is one of th

  28. Y. Taniguchi, M. Ajiki, T. Murayama, T. Nagao

    We report on the discovery of a very narrow-line star forming object beyond redshift of 5. Using the prime-focus camera, Suprime-Cam, on the 8.2 m Subaru telescope together with a narrow-passband filter centered at $λ_{\rm c}$ = 8150 Åwith passband of $Δλ$ = 120 Å, we have obtained a very deep image of the field surrounding the quasar SDSSp J104433.04$-$0125

  29. E. Berger, A. M. Soderberg, D. A. Frail, S. R. Kulkarni

    We present radio observations of GRB 020405 starting 1.2 days after the burst, which reveal a rapidly-fading ``radio flare&#39;&#39;. Based on its temporal and spectral properties, we interpret the radio flare as emission from the reverse shock. This scenario rules out a circumburst medium with a radial density profile ρ~ r^{-2} expected around a mass-losing

  30. Christopher W. Mauche, Duane A. Liedahl, Kevin B. Fournier

    Using the Livermore X-ray Spectral Synthesizer, which calculates spectral models of highly charged ions based on HULLAC atomic data, we investigate the temperature, density, and photoexcitation dependence of the I(11.92 A)/I(11.77 A) line ratio of Fe XXII. Applied to the Chandra HETG spectrum of the intermediate polar EX Hya, we find that the electron densit

  31. Michael R. Meyer

    Over the past decade, tremendous progress has been made in applying the techniques of MK classification to spectra obtained from 1-5 microns. This spectral region is rich in atomic and molecular features which are temperature and luminosity sensitive providing a powerful technique to study intrinsically red and/or heavily dust embedded stellar populations. W

  32. S. Ejiri, K. Kanaya, Y. Namekawa, T. Umeda

    We study a block spin transformation in the SU(3) lattice gauge theory on anisotropic lattices to obtain Iwasaki&#39;s renormalization group improved action for anisotropic cases. For the class of actions with plaquette and $1\times2$ rectangular terms, we determine the improvement parameters as functions of the anisotropy $ξ= a_s/a_t$. We find that the prog

  33. Bruno El-Bennich, W. M Kloet, B. Loiseau

    The large set of accurate data on differential cross section and analyzing power from the CERN LEAR experiment on $\bar pp \to π^+π^-$ in the range from 360 to 1550 MeV/c is well reproduced within a distorted wave approximation approach. The initial $\bar pp$ scattering wave functions originate from a recent $\bar N N$ model. The transition operator is obtai

  34. Chris Blake, Karl Glazebrook

    We show that the baryonic oscillations expected in the galaxy power spectrum may be used as a &#34;standard cosmological ruler&#39;&#39; to facilitate accurate measurement of the cosmological equation of state. Our approach involves a straight-forward measurement of the oscillation &#34;wavelength&#39;&#39; in Fourier space, which is fixed by fundamental lin

  35. Xuedong Hu, S. Das Sarma

    We study theoretically the effects of qubit inhomogeneity on the quantum logic gate of qubit swap, which is an integral part of the operations of a quantum computer. Our focus here is to construct a robust pulse sequence for swap operation in the simultaneous presence of Zeeman inhomogeneity for quantum dot trapped electron spins and the finite-time ramp-up

  36. J. E. Hirsch

    The theory of hole superconductivity proposes that superconductivity originates in the fundamental electron-hole asymmetry of condensed matter and that it is an &#39;undressing&#39; transition. Here we propose that a natural consequence of this theory is that superconductors behave as giant atoms. The model predicts that the charge distribution in supercondu

  37. J. E. Hirsch

    In a solid, transport of electricity can occur via negative electrons or via positive holes. In the normal state of superconducting materials experiments show that transport is usually dominated by $dressed$ $positive$ $hole$ $carriers$. Instead, in the superconducting state experiments show that the supercurrent is always carried by $undressed$ $negative$ $

  38. D. Teaney

    I calculate the first correction to the thermal distribution function of an expanding gas due to shear viscosity. With this modified distribution function I estimate viscous corrections to spectra, elliptic flow, and HBT radii in hydrodynamic simulations of heavy ion collisions using the blast wave model. For reasonable values of the shear viscosity, viscous

  39. Jaume Gomis, Sanefumi Moriyama, Jongwon Park

    We study string interactions among string states with arbitrary impurities in the Type IIB plane wave background using string field theory. We reproduce all string amplitudes from gauge theory by computing matrix elements of the dilatation operator in a previously proposed basis of states. A direct correspondence is found between the string field theory and

  40. Tomaz Rejec, Anton Ramsak

    The zero-temperature linear response conductance through an interacting mesoscopic region attached to noninteracting leads is investigated. We present a set of formulae expressing the conductance in terms of the ground-state energy or persistent currents in an auxiliary system, namely a ring threaded by a magnetic flux and containing the correlated electron

  41. S. Hill, R. S. Edwards, S. I. Jones, J. M. North

    We present detailed angle-dependent single crystal electron paramagnetic resonance (EPR) data for field rotations in the hard plane of the S=10 single molecule magnet Mn12-acetate. A clear four-fold variation in the resonance positions may be attributed to an intrinsic fourth order transverse anisotropy (O44). Meanwhile, a four-fold variation of the EPR line

  42. Robert H. Brandenberger, Masahide Yamaguchi

    We discuss spontaneous baryogenesis in the warm inflation scenario. In contrast with standard inflation models, radiation always exists in the warm inflation scenario, and the inflaton must be directly coupled to it. Also, the transition to the post-inflationary radiation dominated phase is smooth and the entropy is not significantly increased at the end of

  43. K. Schöbel, M. Ansorg

    Using a multi domain spectral method, we investigate systematically the general-relativistic model for axisymmetric uniformly rotating, homogeneous fluid bodies generalizing the analytically known Maclaurin and Schwarzschild solutions. Apart from the curves associated with these solutions and a further curve of configurations that rotate at the mass shedding

  44. M. C. B. Abdalla, A. L. Gadelha, I. V. Vancea

    In this work we explain the construction of the thermal vacuum for the bosonic string, as well that of the thermal boundary state interpreted as a $D_{p}$-brane at finite temperature. In both case we calculate the respective entropy using the entropy operator of the Thermo Field Dynamics Theory. We show that the contribution of the thermal string entropy is

  45. Claire Voisin

    We prove the Green conjecture for generic curves of odd genus. That is we prove the vanishing $K_{k,1}(X,K_X)=0$ for $X$ generic of genus $2k+1$. The curves we consider are smooth curves $X$ on a K3 surface whose Picard group has rank 2. This completes our previous work, where the Green conjecture for generic curves of genus $g$ with fixed gonality $d$ was p

  46. Seungwon Baek

    We consider the chargino contribution to the CP violation in $B \to ϕK_S$ decay in the minimal supersymmetric standard model at large $\tan\be$. It is shown that the Wilson coefficient $C_{8g}$ of the chromomagnetic penguin operator can be significantly enhanced by the chargino-mediated diagrams while satisfying other direct/indirect experimental constraints

  47. J. M. Carmona, J. L. Cortes, J. Gamboa, F. Mendez

    Generalizing the noncommutative harmonic oscillator construction, we propose a new extension of quantum field theory based on the concept of &#34;noncommutative fields&#34;. Our description permits to break the usual particle-antiparticle degeneracy at the dispersion relation level and introduces naturally an ultraviolet and an infrared cutoff. Phenomenologi

  48. A. Dobrzycki, K. Z. Stanek, L. M. Macri, P. J. Groot

    We present five X-ray quasars behind the Small Magellanic Cloud, increasing the number of known quasars behind the SMC by ca. 40%. They were identified via follow-up spectroscopy of serendipitous sources from the Chandra X-ray Observatory matched with objects from the OGLE database. All quasars lie behind dense parts of the SMC, and could be very useful for

  49. Ivan S. Booth, Stephen Fairhurst

    We construct a Hamiltonian formulation of quasilocal general relativity using an extended phase space that includes boundary coordinates as configuration variables. This allows us to use Hamiltonian methods to derive an expression for the energy of a non-isolated region of space-time that interacts with its neighbourhood. This expression is found to be very

  50. Emilio Santos

    Sufficient conditions for (the non-violation of) the Bell-CHSH inequalities in a mixed state of a two-qubit system are: 1) The linear entropy of the state is not smaller than 0.5, 2) The sum of the conditional linear entropies is non-negative, 3) The von Neumann entropy is not smaller than 0.833, 4) The sum of the conditional von Neumann entropies is not sma

  51. C. F. Bird, D. R. Bowler

    Short dangling bond wires (DB wires), fabricated on H-terminated Si(001) surfaces, show patterns of displacement that depend on their length. We have performed density function calculations, with and without spin-polarisation, designed to investigate the atomic and electronic structure of these wires. As expected, we find that even length wires are accuratel

  52. D. Hennig, J. F. R. Archilla

    We investigate the formation process of nonlinear vibrational modes representing broad H-bridge multi--site breathers in a DNA--shaped double strand. Within a network model of the double helix we take individual motions of the bases within the base pair plane into account. The resulting H-bridge deformations may be asymmetric with respect to the helix axis.

  53. Colin Rourke, Brian Sanderson

    This is the third of three papers about the Compression Theorem: if M^m is embedded in Q^q X R with a normal vector field and if q-m > 0, then the given vector field can be straightened (ie, made parallel to the given R direction) by an isotopy of M and normal field in Q X R. The theorem can be deduced from Gromov&#39;s theorem on directed embeddings [M Grom

  54. T. B. Pittman, J. D. Franson

    We report a violation of Bell&#39;s inequality using one photon from a parametric down-conversion source and a second photon from an attenuated laser beam. The two photons were entangled at a beam splitter using the post-selection technique of Shih and Alley [Phys. Rev. Lett. 61, 2921 (1988)]. A quantum interference pattern with a visibility of 91% was obtai

  55. S. Janssen, J. Ryckebusch, T. Van Cauteren

    Results for response functions for kaon electroproduction on the proton are presented. A tree-level hadrodynamical model is adopted and it is shown that some of the electroproduction response functions are particularly powerful with the eye on gaining control over the parameterization of the background diagrams. The existing data set for the p(e,e&#39;K+)Lam

  56. S. S. Bulanov, V. A. Novikov, L. B. Okun, A. N. Rozanov

    The dependence of the Z-resonance shape on the location of the threshold of the N\bar{N} production (N is the 4th generation neutrino) is analyzed. The bounds on the existence of 4th generation are derived from the comparison of the theoretical expression for the Z-lineshape with the experimental data. The 4th generation is excluded at 95% C. L. for m_N<46.7

  57. P. Colangelo, F. De Fazio

    We use light-cone QCD sum rules to evaluate the strong coupling $g_{f_0 K^+ K^-}$ which enters in several analyses concerning the scalar $f_0(980)$ meson. The result: $6.2\le g_{f_0 K^+ K^-}\le 7.8$ GeV is larger than in previous determinations.

  58. V. P. Goncalves, M. V. T. Machado

    The heavy quark production in ultraperipheral heavy ion collisions is investigated, in particular we focus on the results from the coherent interactions given by the two-photon process. One addresses the heavy quark total cross sections at photon level considering the saturation model and the BFKL dynamics in the color dipole picture. The corresponding cross

  59. Shahar Hod

    Black-hole quasinormal modes (QNM) have been the subject of much recent attention, with the hope that these oscillation frequencies may shed some light on the elusive theory of quantum gravity. We compare numerical results for the QNM spectrum of the (rotating) Kerr black hole with an {\it exact} formula Re$ω\to T_{BH}\ln 3+Ωm$, which is based on Bohr&#39;s

  60. Junegone Chay, Chul Kim

    We consider nonleptonic B decays into two light mesons at leading order in soft-collinear effective theory, and show that the decay amplitudes are factorized to all orders in alpha_s. The operators for nonleptonic B decays in the full theory are first matched to the operators in SCET_I, which is the effective theory appropriate for sqrt{m_b Lambda} <mu <m_b

  61. T. Stauber

    The finite-size Tomonaga-Luttinger Hamiltonian with an arbitrary potential is mapped onto a non-interacting Fermi gas with renormalized potential. This is done by means of flow equations for Hamiltonians and is valid for small electron-electron interaction. This method also yields an alternative bosonization formula for the transformed field operator which m

  62. A. V. Pak, D. V. Pavluchenko, S. S. Petrosyan, V. G. Serbo

    Methods of gamma-gamma, gamma-electron luminosities measurement at photon colliders based on Compton scattering of laser photons on high energy electrons at linear colliders are considered.

  63. C. Wetterich

    Crossover quintessence predicts that the time variation of fundamental couplings is substantially faster at redshift $z\approx 2$ than over the past few billion years. This could reconcile the reported time variation of the fine structure constant from quasar absorption lines with severe bounds from archeo-nuclear physics and high precision tests of the equi

  64. A. V. Gichuk, V. P. Neznamov, Yu. V. Petrov

    The paper proposes an algorithm for regularization of the self-energy expressions for a Dirac particle that meets the relativistic and gauge invariance requirements.

  65. Matthew Gursky, Jeff Viaclovsky

    We present a conformal deformation involving a fully nonlinear equation in dimension 4, starting with positive scalar curvature. Assuming a certain conformal invariant is positive, one may deform from positive scalar curvature to a stronger condition involving the Ricci tensor. We also give a new conformally invariant condition for positivity of the Paneitz

  66. M. Higuchi, K. Higuchi

    The Hohenberg-Kohn theorem of the density functional theory is extended by modifying the Levy constrained-search formulation. The new theorem allows us to choose arbitrary physical quantities as the basic variables which determine the ground-state properties of the system. Moreover, the theorem establishes a minimum principle with respect to variations in th

  67. Gregg Jaeger, Mihail Teodorescu-Frumosu, Alexander Sergienko, Bahaa E. A. Saleh

    We investigate the behavior of quantum states under stochastic local quantum operations and classical communication (SLOCC) for fixed numbers of qubits. We explicitly exhibit the homomorphism between complex and real groups for two-qubits, and use the latter to describe the effect of SLOCC operations on two-qubit states. We find an expression for the polariz

  68. Aalok Pandya, Ashok K. Nagawat

    In this paper, the projective geometry is used to describe the features of spherical manifold and discreteness in quantum evolution. As a system evolves in time the state vector changes and it traces out a curve in Hilbert space. Geometrically, the evolution is represented as a closed curve in the projective Hilbert space. In recent times many attempts have

  69. D. Mauro

    In this thesis we study several features of the operatorial approach to classical mechanics pionereed by Koopman and von Neumann (KvN) in the Thirties. In particular in the first part we study the role of the phases of the KvN states. We analyze, within the KvN theory, the two-slit experiment and the Aharonov-Bohm effect and we make a comparison between the

  70. I. L. Egusquiza, L. J. Garay

    Real clocks are not perfect. This must have an effect in our predictions for the behaviour of a quantum system, an effect for which we present a unified description encompassing several previous proposals. We study the relevance of clock errors in the Zeno effect, and find that generically no Zeno effect can be present (in such a way that there is no contrad

  71. F. Brau

    In a recent article, Sastry has proposed a quantum mechanics of smeared particles. We show that the effects induced by the modification of the Heisenberg algebra, proposed to take into account the delocalization of a particle defined via its Compton wavelength, are important enough to be excluded experimentally.

  72. Z. Y. Zeng, G. J. Zeng, L. M. Kuang, L. D. Zhang

    We studied the dynamic effects of an electromagnetic(EM) wave with circular polarization on a two-level damped atom. The results demonstrate interesting ac Stark split of energy levels of damped atom. The split levels have different energies and lifetimes, both of which depend on the interaction and the damping rate of atom. When the frequency of the EM wave

  73. Fam Le Kien, K. Hakuta

    We investigate the parametric beating of a quantum probe field with a prepared Raman coherence in a far-off-resonance medium, and describe the resulting multiplexing processes. We show that the normalized autocorrelation functions of the probe field are exactly reproduced in the Stokes and anti-Stokes sideband fields. We find that an initial coherent state o

  74. Kazuyuki Fujii

    In this paper we treat the 2--level system interacting with external fields without the rotating wave approximation and construct some approximate solutions in the strong coupling regime.

  75. A. J. Brizard, E. R. Tracy

    A mini-conference on Hamiltonian and Lagrangian methods in fluid and plasma physics was held on November 14, 2002, as part of the 44th meeting of the Division of Plasma Physics of the American Physical Society. This paper summarizes the material presented during the talks scheduled during the Mini-Conference, which was held to honor Allan Kaufman on the occa

  76. A. A. Kozlov

    The original method of treatment of various pathological processes in human skin covers is described. The method has a brightly expressed differential action: destroying pathologic cells it does not render any influence on healthy cells. The examples of application of a method for treatment of some kinds of skin pathologies are given.

  77. Juhao Wu, Tor Raubenheimer, Gennady Stupakov

    Most studies of Coherent Synchrotron Radiation (CSR) have only considered the radiation from independent dipole magnets. However, in the damping rings of future linear colliders, a large fraction of the radiation power will be emitted in damping wigglers. In this paper, the longitudinal wakefield and impedance due to CSR in a wiggler are derived in the limit

  78. P. J. Borycki, J. Ginocchio, W. Nazarewicz, M. Stoitsov

    Using relations between wave functions obtained in the framework of the relativistic mean field theory, we investigate the effects of pseudospin and spin symmetry breaking on the single nucleon wave functions in spherical nuclei. In our analysis, we apply both relativistic and non-relativistic self-consistent models as well as the harmonic oscillator model.

  79. G. Gori, F. Barranco, E. Vigezzi, R. A. Broglia

    The coupling of single-particle motion and of vibrations in $^{11}_4$Be produces dressed neutrons which spend only a fraction of the time in pure single-particle states, and which weighting differently from the bare neutrons, lead to parity inversion. The interaction of the two least bound neutrons in the ground state of $^{12}_4$Be mediated by the $v_{14}$

  80. M. A. Huertas

    In a previous paper, the convergence of the effective field theory approach of Furnstahl, Serot and Tang to the nuclear many-body problem was studied by applying it to selected doubly-magic, and neighboring single-particle and single-hole, nuclei far from stability. The success of that approach, interpreted through density functional theory, would imply reli

  81. Rene Friedrichs, Andreas Engel

    We derive a closed equation for the shape of the free surface of a magnetic fluid subject to an external magnetic field. The equation is strongly non-local due to the long range character of the magnetic interaction. We develop a systematic multiple scale perturbation expansion in which the non-locality is reduced to the occurrence of the Hilbert transform o

  82. Chavalarias David, Bourgine Paul

    The aim of this article is to address the question of the endogenization of mimetic processes in formal models of social systems. Starting from some studies about cognitive differences between humans and animals, we propose a formal framework which has the advantage to endogenise mimetic rules and give a comprehensive description of a heterogeneous populatio

  83. R. Fioresi, M. A. Lledo

    In this paper we study algebraic supergroups and their coadjoint orbits as affine algebraic supervarieties. We find an algebraic deformation quantization of them that can be related to the fuzzy spaces of non commutative geometry.

  84. Frederic Laurent-Polz

    We study the dynamics of $N$ point vortices on a rotating sphere. The Hamiltonian system becomes infinite dimensional due to the non-uniform background vorticity coming from the Coriolis force. We prove that a relative equilibrium formed of latitudinal rings of identical vortices for the non-rotating sphere persists to be a relative equilibrium when the sphe

  85. Camille Plenat

    This paper deals with the Nash problem, which claims that there are as many families of arcs on a singular germ of surface $U$ as there are essential components of the exceptional divisor in the desingularisation of this singularity. Let $\mathcal{H}=\bigcup \bar{N_α}$ be a particular decomposition of the set of arcs on $U$, described later on. We give two n

  86. Elizabeth Stanhope

    We first show that a Laplace isospectral family of Riemannian orbifolds, satisfying a lower Ricci curvature bound, contains orbifolds with points of only finitely many isotropy types. If we restrict our attention to orbifolds with only isolated singularities, and assume a lower sectional curvature bound, then the number of singular points in an orbifold in s

  87. Roger Fenn, Colin Rourke, Brian Sanderson

    We study cubical sets without degeneracies, which we call square sets. These sets arise naturally in a number of settings and they have a beautiful intrinsic geometry; in particular a square set C has an infinite family of associated square sets J^i(C), i=1,2,..., which we call James complexes. There are mock bundle projections p_i:|J^i(C)|-->|C| (which we c

  88. R. M. Brouwer

    Rings form a bicategory [Rings], with classes of bimodules as horizontal arrows, and bimodule maps as vertical arrows. The notion of Morita equivalence for rings can be translated in terms of bicategories in the following way. Two rings are Morita equivalent if and only if they are isomorphic objects in the bicategory. We repeat this construction for von Neu

  89. Francesca Antoci

    We give some necessary conditions and sufficient conditions for the compactness of the embedding of Sobolev spaces $W^{1,p}(Ω,w) \to L^p(Ω,w),$ where $w$ is some weight on a domain $Ω\subset \Real^n$.

  90. M. Zakai

    The paper considers (a) Representations of measure preserving transformations (``rotations&#39;&#39;) on Wiener space, and (b) The stochastic calculus of variations induced by parameterized rotations $\{T_θw, 0 \le θ\le \eps\}$: ``Directional derivatives&#39;&#39; $(dF(T_θw)/d θ)_{θ=0}$, ``vector fields&#39;&#39; or ``tangent processes&#39;&#39; $(dT_θw /dθ)

  91. Nicolas Burq

    Consider $M$, a bounded domain in ${\mathbb R}^d$, which is a Riemanian manifold with piecewise smooth boundary and suppose that the billiard associated to the geodesic flow reflecting on the boundary acording to the laws of geometric optics is ergodic. We prove that the boundary value of the eigenfunctions of the Laplace operator with reasonable boundary co

  92. Jean-Marc Schlenker

    Let $P$ be a (non necessarily convex) embedded polyhedron in $\R^3$, with its vertices on an ellipsoid. Suppose that the interior of $P$ can be decomposed into convex polytopes without adding any vertex. Then $P$ is infinitesimally rigid. More generally, let $P$ be a polyhedron bounding a domain which is the union of polytopes $C_1, ..., C_n$ with disjoint i

  93. Veronica Felli

    We study the problem of existence of surfaces in ${\bf R}^3$ parametrized on the sphere ${\mathbb S}^2$ with prescribed mean curvature $H$ in the perturbative case, i.e. for $H=H_0+εH_1$, where $H_0$ is a nonzero constant, $H_1$ is a $C^2$ function and $ε$ is a small perturbation parameter.

  94. Casim Abbas

    See http://www.math.msu.edu/~abbas or Wiley preprint server.

  95. A. Burstein, T. Mansour

    We find generating functions the number of strings (words) containing a specified number of occurrences of certain types of order-isomorphic classes of substrings called subword patterns. In particular, we find generating functions for the number of strings containing a specified number of occurrences of a given 3-letter subword pattern.

  96. V. P. Akulov, Oktay Cebecioglu, A. Pashnev

    In the framework of nonlinear realizations we rederive the action of the N=2 SuperConformal Quantum Mechanics (SCQM). We propose also the WZNW -- like construction of the interaction term in the lagrangian with the help of Cartan&#39;s Omega forms.

  97. El Mostapha Sahraoui

    The baryon vertex of IIB superstring theory on $AdS_{5}\times \mathbb{R}P^{5}$, for the case of orthogonal groups, is studied. The energy of the three brane decayed from an original five brane is calculated explicitly. The radius of this decayed three brane, for a BPS configuration, is also given and interpreted.

  98. Chia-Hung V. Chang, We-Fu Chang, John N. Ng

    We study the generation of neutrino masses in the $SU(3)_W$ electroweak unified theory in $M_4\times S_1/(Z_2\times Z&#39;_2)$ spacetime. By appropriate orbifolding, the bulk symmetry $SU(3)_W$ is broken into $SU(2)_L \times U(1)_Y$ at one of the fixed points, where the quarks reside. The leptons form $SU(3)_W$ triplets, localized at the other symmetric fixe

  99. L. Afanasyev, A. Lanaro, J. Schacher

    These are the proceedings of the workshop &#34;HadAtom02&#34;, held at the CERN, October 14 - 15, 2002. The main topic of the workshop concerned the physics of hadronic atoms and in this contest recent results from experiments and theory were presented. These proceedings contain the list of participants, the scientific program and a short contribution from e

  100. Massimo Giovannini

    In quintessential inflationary model, the same master field that drives inflation becomes, later on, the dynamical source of the (present) accelerated expansion. Quintessential inflationary models require a curvature scale at the end of inflation around $10^{-6}M_{\rm P}$ in order to explain the large scale fluctuations observed in the microwave sky. If the