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August 1999 arXiv papers — page 13

Showing 1,2011,300 of 2,072 papers

  1. Erick J. Weinberg

    Magnetic monopole solutions naturally arise in the context of spontaneously broken gauge theories. When the unbroken symmetry includes a non-Abelian subgroup, investigation of the low-energy monopole dynamics by means of the moduli space approximation reveals degrees of freedom that can be attributed to massless monopoles. These do not correspond to distinct

  2. Erick J. Weinberg

    I review some aspects of BPS magnetic monopoles and of electric-magnetic duality in theories with arbitrary gauge groups. When the symmetry is maximally broken to a U(1)^r subgroup, all magnetically charged configurations can be understood in terms of r species of massive fundamental monopoles. When the unbroken group has a non-Abelian factor, some of these

  3. Eduardo Eyras, Yolanda Lozano

    We construct the effective action of certain exotic branes in the Type II theories which are not predicted by their spacetime supersymmetry algebras. We analyze in detail the case of the NS-7B brane, S-dual to the D7-brane, and connected by T-duality to other exotic branes in Type IIA: the KK-6A brane and the KK-8A brane (obtained by reduction of the M-theor

  4. Reza Tavakol, George Ellis

    We consider a recent generalisation by Bousso of an earlier holography proposal by Fischler and Susskind. We demonstrate that in general inhomogeneous universes such a proposal would involve extremely complicated - possibly fractal - light sheets. Furthermore, in general such a light sheet cannot be known a priori on the basis of theory and moreover, the evo

  5. O. J. P. Eboli, T. Han, M. B. Magro, P. G. Mercadante

    We analyze the potentiality of hadron colliders to search for large extra dimensions via the production of photon pairs. The virtual exchange of Kaluza--Klein gravitons can significantly enhance this processes provided the quantum gravity scale ($M_S$) is in the TeV range. We studied in detail the subprocesses $q \bar{q} \to γγ$ and $g g \to γγ$ taking into

  6. Chris Quigg

    As an introduction to NuFact '99, the ICFA/ECFA Workshop on Neutrino Factories Based on Muon Storage Rings, I place the issues of neutrino properties and neutrino oscillations in the broader context of fermion flavor.

  7. J. R. Hiller

    Calculations in a (3+1)-dimensional model indicate that Pauli-Villars regularization can be combined with discrete light-cone quantization (DLCQ) to solve at least some field theories nonperturbatively. Discrete momentum states of Pauli-Villars particles are included in the Fock basis to automatically generate needed counterterms; the resultant increase in b

  8. M. C. Banuls, J. Bernabeu

    The observables used in the K-system to characterize T and CPT violation are no longer useful for the Bd-system, since the width difference between the physical states is vanishingly small. We show that only Im(epsilon) and Re(delta) can survive if Delta Gamma=0, and build alternative CP-odd, CPT-odd, T-odd and temporal asymmetries for the (B_CP -> B0, B0bar

  9. C. Panagiotakopoulos, K. Tamvakis

    We construct a new minimal extension of the Minimal Supersymmetric Standard Model (MSSM) by promoting the $μ$-parameter to a singlet superfield. The resulting renormalizable superpotential is enforced by a $\mathcal{Z}_5$ $R$-symmetry which is imposed on the non-renormalizable operators as well. The proposed model provides a natural solution to the $μ$-probl

  10. S. I. Alekhin, A. L. Kataev

    We perform a detailed NLO analysis of the combined CCFR xF_3 and F_2 structure functions data and extract the value of alpha_s, parameters of distributions and higher-twist (HT) terms using a direct solution of the DGLAP equation. The value of alpha_s(M_Z)=0.1222\pm 0.0048 (exp) \pm 0.0026 (theor) is obtained. Our results has a larger central value and error

  11. Rodolfo Sassot

    Recent data on diffractive photoproduction of dijets are analyzed within the framework of fracture functions and paying special attention to the consequences of the use of different rapidity gap definitions in order to identify diffractive events. Although these effects are found to be significant, it is shown that once they are properly taken into account,

  12. Merab Gogberashvili

    The solution of Einsteins equations for 4-brane embedded in 5-dimensional Anti-de-Sitter space-time is found. It is shown that the cosmological constant can provide the existence of ordinary 4-dimensional Newton's low and trapping of a matter on the brane.

  13. P. McIntyre, E. Accomando, R. Arnowitt, B. Dutta

    Recent advances in superconductor properties and superconducting magnet technology have made it possible to build cost-effective, high-performance dipoles with a field of 12 Tesla - 3 times the field strength of the Tevatron. Such magnets could be used to upgrade Fermilab's collider in its existing tunnel to a collision energy $\sqrt s$= 6 TeV and lumino

  14. A. Deshpande

    Several important and unique measurements, within the standard model and of possible physics beyond it, could be made with {\em polarized HERA} in which both the proton and the electron beams are polarized. With a $\sim$820 GeV proton beam and a $\sim$27.6 GeV electron beam, the polarized HERA will enable $\vec{e}-\vec{p}$ collisions with $\sqrt{s} \sim 300$

  15. David Garfinkle, Curt Cutler, G. Comer Duncan

    We perform numerical simulations of the critical gravitational collapse of a spherically symmetric scalar field in 6 dimensions. The critical solution has discrete self-similarity. We find the critical exponent γand the self-similarity period Δ.

  16. Karl Martel

    Coalescing compact binaries have been pointed out as the most promising source of gravitational waves for kilometer-size interferometers such as LIGO. Gravitational wave signals are extracted from the noise in the detectors by matched filtering. This technique performs really well if an a priori theoretical knowledge of the signal is available. The informati

  17. C. Klein, O. Richter

    Disks of collisionless particles are important models for certain galaxies and accretion disks in astrophysics. We present here a solution to the stationary axisymmetric Einstein equations which represents an infinitesimally thin dust disk consisting of two streams of particles circulating with constant angular velocity in opposite directions. These streams

  18. Joseph O'Rourke

    Two results in "computational origami" are illustrated.

  19. D. Dulic, D. van der Marel, A. A. Tsvetkov, W. N. Hardy

    The c-axis Josephson plasmon in optimally doped single-layer and bi-layer high Tc cuprates Tl2201 and Tl2212 have been investigated using infrared spectroscopy. We observed the plasma frequencies for these two compounds at 27.8 and 25.6 cm-1 respectively, which we interpret as a Josephson resonance across the TlO blocking layers. No maximum in the temperatur

  20. A. Buldum, S. Ciraci, C. Y. Fong

    We studied the phononic heat transfer through an atomic dielectric wire with both infinite and finite lengths by using a model Hamiltonian approach. At low temperature under ballistic transport, the thermal conductance contributed by each phonon branch of a uniform and harmonic chain cannot exceed the well-known value which depends linearly on temperature bu

  21. M. S. L. du Croo de Jongh

    This thesis gives an extension for the Density Matrix Renormalisation Group (DMRG) to two dimensions and described a newly developed combination of the DMRG and a Green Function Monte Carlo simulation (GFMC). The first two chapters focus on the DMRG method. The properties are reviewed and it is shown that good quality results can be obtained for two-dimensio

  22. Philip B. Allen, Seth Aubin, R. B. Doak

    The diatomic linear chain of masses coupled by harmonic springs is a textboook model for vibrational normal modes (phonons) in crystals. In addition to propagating acoustic and optic branches, this model is known to support a ``gap mode'' localized at the surface, provided the atom at the surface has light rather than heavy mass. An elementary argume

  23. T. Herrmann, W. Nolting

    The stability of ferromagnetism at the surface at finite temperatures is investigated within the strongly correlated Hubbard model on a semi-infinite lattice. Due to the reduced surface coordination number the effective Coulomb correlation is enhanced at the surface compared to the bulk. Therefore, within the well-known Stoner-picture of band ferromagnetism

  24. Dietmar Weinmann, Sigmund Kohler, Gert-Ludwig Ingold, Peter Hänggi

    As a function of the disorder strength in a mesoscopic system, the electron dynamics crosses over from the ballistic through the diffusive towards the localized regime. The ballistic and the localized situation correspond to integrable or regular behavior while diffusive conductors correspond to chaotic behavior. The chaotic or regular character of single wa

  25. G. Michalek, J. Martinek, J. Barnas, B. R. Bulka

    Spin dependent single electron tunneling in a ferromagnetic double junction is investigated theoretically in the limit of incoherent sequential tunneling. The junction consists of a small nonmagnetic metallic grain with discrete energy levels, which is connected to two ferromagnetic electrodes. We have developed a new theoretical model taking into account ch

  26. Shigeki Onoda, Masatoshi Imada

    We investigate pseudogap phenomena in the 2D electron system. Based on the mode-mode coupling theory of antiferromagnetic (AFM) and $d_{x^2-y^2}$-wave superconducting ($d$SC) fluctuations, single-particle dynamics is analyzed. For the parameter values of underdoped cuprates, pseudogap structure grows in the single-particle spectral weight $A(k,ω)$ around the

  27. A. Iomin, S. Fishman

    It is shown that a family of models associated with the kicked Harper model is relevant for cyclotron resonance experiments in an antidot array. For this purpose a simplified model for electronic motion in a related model system in presence of a magnetic field and an AC electric field is developed. In the limit of strong magnetic field it reduces to a model

  28. Takeo Kato, Masatoshi Imada

    Thermodynamics and transport properties of resistance-shunted Josephson junctions are studied theoretically in the tight-binding limit E_C/E_J<<1, where E_C and E_J are a charging energy and a Josephson coupling energy respectively. Based on a phenomenological harmonic-oscillator model, weak coupling region K=R_Q/R<<1 is analytically studied, where R and R_Q

  29. Yoichi Ando, G. S. Boebinger, A. Passner, L. F. Schneemeyer

    We present the resistively-determined upper critical field H^ρ_{c2}(T) and the irreversibility lines H^ρ_{irr}(T) of various high-T_c cuprates, deduced from measurements in 61-T pulsed magnetic fields applied parallel to the c-axis. The SHAPE of both H^ρ_{c2}(T) and H^ρ_{irr}(T) depends monotonically on the anisotropy of the material and none of the samples

  30. J. E. Larkin, I. S. McLean, J. R. Graham, E. E. Becklin

    This paper presents infrared spectra taken with the newly commissioned NIRSPEC spectrograph on the Keck Telescope of the High Redshift Radio Galaxy MRC 2025-218 (z=2.630) and an extremely red galaxy (R-K > 6 mag) 9&#39;&#39; away. These observations represent the deepest infrared spectra of a radio galaxy to date and have allowed for the detection of Hbeta,

  31. Renyue Cen

    I present an overview of some of the recent advances in our understanding of the distribution and evolution of the ordinary, baryonic matter in the universe. Two observations that strongly suggest that most of the baryons seen at high redshift ($z\ge 2$) have turned into some forms yet undetected at $z=0$ are highlighted. With the aid of large-scale cosmolog

  32. Brad K. Gibson, Peter B. Stetson, Wendy L. Freedman, Jeremy R. Mould

    Cepheid-based distances to seven Type Ia supernovae (SNe)-host galaxies have been derived using the standard HST Key Project on the Extragalactic Distance Scale pipeline. For the first time, this allows for a transparent comparison of data accumulated as part of three different HST projects, the Key Project, the Sandage et al. Type Ia SNe program, and the Ta

  33. Tereasa G. Brainerd, Casey J. Law, James Brauher, S. G. Djorgovski

    We present a preliminary measurement of the angular clustering of faint ($R \le 25$) field galaxies in which we concentrate on the behavior of $w(θ)$ on small angular scales ($θ\ls 10&#39;&#39;$). The galaxies are strongly clustered and $w(θ)$ is well-characterized by a power law of the form $A_w θ^{-δ}$. The best-fitting value of the power law index, $δ$, i

  34. Andrew F. Nelson, Willy Benz

    We present 2D hydrodynamic simulations of circumstellar disks around protostars using a `Piecewise Parabolic Method&#39; (PPM) code. We include a point mass embedded within the disk and follow the migration of that point mass through the disk. Companions with masses $M_c\ga 0.5M_J$ can open a gap in the disk sufficient to halt rapid migration through the dis

  35. Andrew F. Nelson, Willy Benz, Tamara Ruzmaikina

    We present a series of 2-d ($r,ϕ$) hydrodynamic simulations of marginally self gravitating disks around protostars using an SPH code. We implement simple dynamical heating and we cool each location as a black body, using a photosphere temperature obtained from the local vertical structure. We synthesize SEDs from our simulations and compare them to fiducial

  36. F. Combes

    Recent progress in the understanding of the role of bars and gravitational instabilities in galaxy disks is reviewed. It has been proposed that bars can produce mass transfer towards the center, and progressively metamorphose late-type galaxies in early-types, along the Hubble sequence. Through this mass transfer, bars are self-destroyed, and can act only du

  37. Martino Romaniello, Nino Panagia, Salvatore Scuderi

    We have studied the stellar populations in a region of 30 pc around SN 1987A in the Large Magellanic Cloud using multi-band HST-WFPC2 images. The effective temperature, luminosity and reddening of each detected star were determined by fitting the measured broad band magnitudes to the ones calculated with model atmospheres. The resulting HR diagram reveals th

  38. E. F. Bell, W. J. G. de Blok

    We have assessed the significance of Tully and Verheijen&#39;s (1997) bimodal Ursa Major Cluster spiral galaxy near-infrared surface brightness distribution, focussing on whether this bimodality is simply an artifact of small number statistics. A Kolmogorov-Smirnov style of significance test shows that the total distribution is fairly represented by a single

  39. S. G. Djorgovski, S. C. Odewahn, R. R. Gal, R. Brunner

    We report on the current status of our search for protoclusters around quasars at z > 4. While the search is still very incomplete, clustered companion galaxies are found in virtually every case examined so far. The implied comoving number densities of protogalaxies are two to four orders of magnitude higher than expected for the general field, but are compa

  40. Geoffrey C. Bower

    We give a progress report on a snapshot 86 GHz-VLBI survey of the EGRET blazars with the observatories of the CMVA. A high fraction (17/18) of the EGRET blazars were detected on the Pico Veleta-Onsala baseline with a baseline length on the order of 500 $Mλ$. The detection threshold on the Pico Veleta-Onsala baseline was $\sim 0.2$ Jy. Six of these sources we

  41. J. G. Cuby, P. Saracco, A. F. M. Moorwood, S. D&#39;Odorico

    We report the discovery of an isolated brown dwarf with similar properties to the binary object Gliese 229B and to the newly discovered field brown dwarf SDSS 1624+00. Although exhibiting similar colors, its magnitude of ~20.5 is about 6 and 5 magnitudes fainter than Gliese 229B and SDSS 1624+00 respectively. This is the third methane brown dwarf reported to

  42. Yu-Chung N. Cheng, Lawrence M. Krauss

    We re-analyze constraints on the cosmological constant that can be obtained by examining the statistics of strong gravitational lensing of distant quasars by intervening galaxies, focusing on uncertainties in galaxy models (including velocity dispersion, luminosity functions, core radii and magnification bias effects) and on the parameters of the galaxy dist

  43. A. S. Alexandrov, A. M. Bratkovsky

    We calculate the value of the Fröhlich electron-phonon interaction in manganites, cuprates, and some other charge-transfer insulators and show that this interaction is much stronger than any relevant magnetic interaction. A polaron shift due to the Fröhlich interaction, which is about 1 eV, suggests that carriers in those systems are small (bi)polarons at al

  44. L. S. Levitov

    Critical states are studied by a real space RG in the problem with strong diagonal disorder and long range power law hopping. The RG flow of the distribution of coupling parameters is characterized by a family of non-trivial fix points. We consider the RG flow of the distribution of participation ratios of eigenstates. Scaling of participation ratios is sens

  45. Fabian H. L. Essler

    We analyse the three-particle scattering continuum in quasi one dimensional integer spin Heisenberg antiferromagnets within a low-energy effective field theory framework. We exactly determine the zero temperature dynamical structure factor in the O(3) nonlinear sigma model and in Tsvelik&#39;s Majorana fermion theory. We study the effects of interchain coupl

  46. A. N. Soklakov, R. Schack

    We derive a simple closed form for the matrix elements of the quantum baker&#39;s map that shows that the map is an approximate shift in a symbolic representation based on discrete phase space. We use this result to give a formal proof that the quantum baker&#39;s map approaches a classical Bernoulli shift in the limit of a small effective Plank&#39;s consta

  47. F. Halzen, D. W. Hooper

    We recalculate the diffuse flux of high energy neutrinos produced by Gamma Ray Bursts (GRB) in the relativistic fireball model. Although we confirm that the average single burst produces only ~10^{-2} high energy neutrino events in a detector with 1 km^2 effective area, i.e. about 10 events per year, we show that the observed rate is dominated by burst-to-bu

  48. D. Bazeia, F. A. Brito

    We present a way of tiling the plane with a regular hexagonal network of defects. The network is stable and follows in consequence of the three-junctions that appear in a model of two real scalar fields that presents $Z_3$ symmetry. The $Z_3$ symmetry is effective in both the vacuum and defect sectors, and no supersymmetry is required to build the network.

  49. N. S. Deger, A. Kaya, E. Sezgin, P. Sundell

    We couple n copies of N=(2,0) scalar multiplets to a gauged N=(2,0) supergravity in 2+1 dimensions which admits AdS_3 as a vacuum. The scalar fields are charged under the gauged R-symmetry group U(1) and parametrize certain Kahler manifolds with compact or non-compact isometries. The radii of these manifolds are quantized in the compact case, but arbitrary o

  50. A. C. Durst, P. A. Lee

    Due to the node structure of the gap in a d-wave superconductor, the presence of impurities generates a finite density of quasiparticle excitations at zero temperature. Since these impurity-induced quasiparticles are both generated and scattered by impurities, prior calculations indicate a universal limit (Ω-> 0, T -> 0) where the transport coefficients obta

  51. A. M. Bratkovsky, A. P. Levanyuk

    We study the domain structure in ferroelectric thin films with a `passive&#39; layer (material with damaged ferroelectric properties) at the interface between the film and electrodes within a continuous medium approximation. An abrupt transition from a monodomain to a polydomain state has been found with the increase of the `passive&#39; layer thickness $d$.

  52. J. Schaffner-Bielich, R. Mattiello, H. Sorge

    Weak SU(3) symmetry is successfully applied to the weak hadronic decay amplitudes of octet hyperons. Weak nonmesonic and mesonic decays of various dibaryons with strangeness, their dominant decay modes, and lifetimes are calculated. Production estimates for BNL&#39;s Relativistic Heavy-Ion Collider are presented employing wave function coalescence. Signals f

  53. S. Flach, O. Yevtushenko, Y. Zolotaryuk

    We consider the classical dynamics of a particle in a one-dimensional space-periodic potential U(X) = U(X+2π) under the influence of a time-periodic space-homogeneous external field E(t)=E(t+T). If E(t) is neither symmetric function of t nor antisymmetric under time shifts $E(t \pm T/2) \neq -E(t)$, an ensemble of trajectories with zero current at t=0 yields

  54. N. Kivel, L. Mankiewicz, M. V. Polyakov

    We have calculated the NLO corrections for the leading twist amplitude of the reaction $γ^*γ\toππ$ at large virtuality of the photon and at $W^2\ll Q^2$. With a simple model for the two-pion quark and gluon distribution amplitudes we have estimated that the NLO effects may reduce the leading-order amplitude by as much as 30%. We have found that besides the u

  55. Keshav Dasgupta, Govindan Rajesh, Savdeep Sethi

    We study the properties of M and F theory compactifications to three and four dimensions with background fluxes. We provide a simple construction of supersymmetric vacua, including some with orientifold descriptions. These vacua, which have warp factors, typically have fewer moduli than conventional Calabi-Yau compactifications. The mechanism for anomaly can

  56. Alister W. Graham, Mercedes Prieto

    We investigate recent claims that the Hubble sequence of spiral galaxies is scale-free. Fundamental to this investigation is the fact that within the photometric data of 86 spiral galaxies from de Jong & van der Kruit - from which these claims were made - a trend exists between morphological type and bulge profile shape. While late-type spiral bulges are des

  57. Jayita Chatterjee, A. N. Das

    The two-site single-polaron problem is studied within the perturbative expansions using different standard phonon basis obtained through the Lang Firsov (LF), modified LF (MLF) and modified LF transformation with squeezed phonon states (MLFS). The role of these convergent expansions using the above prescriptions in lowering the energy and in determining the

  58. S. Capitani, M. Göckeler, R. Horsley, B. Klaus

    We present quenched lattice QCD results for the contribution of higher-twist operators to the lowest non-trivial moment of the pion structure function. To be specific, we consider the combination $F_2^{π^+} + F_2^{π^-} - 2 F_2^{π^0}$ which has $I = 2$ and receives contributions from 4-Fermi operators only. We introduce the basis of lattice operators. The ren

  59. Elena Gubankova, Chueng-Ryong Ji, Stephen R. Cotanch

    The systematic approach to study bound states in quantum chromodynamics is presented. The method utilizes nonperturbative flow equations in the confining background, that makes possible to perform perturbative renormalization and to bring the QCD Hamiltonian to a block-diagonal form with the number of quasiparticles conserving in each block. The effective bl

  60. Mario Eudave-Munoz

    We show that for each pair of positive integers g and n, there are infinitely many tunnel number one knots, whose exteriors contain an essential meridional surface of genus g, and with 2n boundary components. We also show that for each positive integer n, there are tunnel number one knots whose exteriors contain n disjoint, non-parallel, closed incompressibl

  61. Jose L. Cereceda

    In this paper the failure of Hardy&#39;s nonlocality proof for the class of maximally entangled states is considered. A detailed analysis shows that the incompatibility of the Hardy equations for this class of states physically originates from the fact that the existence of quantum perfect correlations for the three pairs of two-valued observables (D_11,D_21

  62. V. V. Dodonov, M. A. Andreata

    We obtain explicit analytical expressions for the quadrature variances and the photon distribution functions of the electromagnetic field modes excited from vacuum or thermal states due to the non-stationary Casimir effect in an ideal one-dimensional Fabry--Perot cavity with vibrating walls, provided the frequency of vibrations is close to a multiple frequen

  63. G. J. Milburn

    We show how a conditional displacement of the vibrational mode of trapped ions can be used to simulate nonlinear collective and interacting spin systems including nonlinear tops and Ising models (a universal two qubit gate), independent of the vibrational state of the ion. Thus cooling to the vibrational ground state is unnecessary provided the heating rate

  64. Samuel L. Braunstein, Giacomo M. D&#39;Ariano, G. J. Milburn, Massimiliano F. Sacchi

    We give a transfer theorem for teleportation based on twisting the entanglement measurement. This allows one to say what local unitary operation must be performed to complete the teleportation in any situation, generalizing the scheme to include overcomplete measurements, non-abelian groups of local unitary operations (e.g., angular momentum teleportation),

  65. Jeeva S. Anandan

    The nature of a physical law is examined, and it is suggested that there may not be any fundamental dynamical laws. This explains the intrinsic indeterminism of quantum theory. The probabilities for transition from a given initial state to a final state then depends on the quantum geometry that is determined by symmetries, which may exist as relations betwee

  66. Pretterebner Julius

    This article shows the relations between the electricity, magnetism, gravity and mechanics by presenting an existing hidden structure in the Maxwell equations. This hidden structure allows to discover the classical physic from a new point of view leading to the unified theory (UT).

  67. J. N. Abdurashitov, T. V. Ibragimova, A. V. Kalikhov

    A kind of analysis of waveform of voltage pulse in small proportional counter is described. The technique is based on deconvolution of recorded pulse with a response function of the counter. It allows one to restore a projection of the track of initial ionization to the radius of the counter, or a charge collection function.

  68. P. Maris, P. C. Tandy

    The ladder Bethe-Salpeter solution for the dressed photon-quark vertex is used to study the low-momentum behavior of the pion electromagnetic and the $γ^\star π^0 γ$ transition form factors. With model parameters previously fixed by light meson masses and decay constants, the low-momentum slope of both form factors is in excellent agreement with the data. In

  69. P. Maris

    The masses and decay constants of the light mesons are studied within a ladder-rainbow truncation of the set of Dyson-Schwinger equations using a model 2-point gluon function. The one phenomenological parameter and two current quark masses are fitted to reproduce $f_π$, $m_π$ and $m_K$. Our results for $f_K$, and for the vector mesons $ρ$, $ϕ$, and $K^\star$

  70. J. Meng, I. Tanihata

    The Relativistic Continuum Hartree Bogoliubov theory (RCHB), which is the extension of the Relativistic Mean Field and the Bogoliubov transformation in the coordinate representation, has been used to study tin isotopes. The pairing correlation is taken into account by a density-dependent force of zero range. RCHB is used to describe the even-even tin isotope

  71. Yuri Kondratiev, Jose Luis Silva, Michael Roeckner

    In this paper we extend the result obtained in \cite{AKR97} (see also \cite {AKR96}) on the representation of the intrinsic pre- Dirichlet form $\mathcal{E}_{π_σ}^Γ$ of the Poisson measure $π_σ$ in terms of the extrinsic one $\mathcal{E}_{π_σ,H_σ^{X}}^{P}$. More precisely, replacing $π_σ$ by a Gibbs measure $μ$ on the configuration space $Γ_{X}$ we derive a

  72. Andreas Gathmann

    For any smooth complex projective variety X and smooth very ample hypersurface Y in X, we develop the technique of genus zero relative Gromov-Witten invariants of Y in X in algebro-geometric terms. We prove an equality of cycles in the Chow groups of the moduli spaces of relative stable maps that relates these relative invariants to the Gromov-Witten invaria

  73. Nguyen Quoc Tho

    We propose in this paper the construction of non-commutative Chern characters of the C*-algebras of spheres and quantum spheres. The final computation gives us a clear relation with the ordinary Z/(2)-graded Chern characters of tori or their normalizers.

  74. Gilles Pisier

    We give an alternate proof of one of the inequalities proved recently for martingales (=sums of martingale differences) in a non-commutative $L_p$-space, with $1<p<\infty$, by Q. Xu and the author. This new approach is restricted to $p$ an even integer, but it yields a constant which is $O(p)$ when $p\to \infty$ and it applies to a much more general kind of

  75. Alexandre A. Panin, Anatoly V. Yakovlev

    We construct Galois theory for sublattices of certain complete modular lattices and their automorphism groups. A well-known description of the intermediate subgroups of the general linear group over an Artinian ring containing the group of diagonal matrices, due to Z.I.Borewicz and N.A.Vavilov, can be obtained as a consequence of this theory.

  76. Alexandre A. Panin

    A complete description of subgroups in the general linear group over a semilocal ring containing the group of diagonal matrices was obtained by Z.I.Borewicz and N.A.Vavilov. It is shown in the present paper that a similar description holds for the intermediate subgroups of the group of all automorphisms of the lattice of right submodules of a free finite ran

  77. John H. Schwarz

    Following Sen&#39;s discovery of various stable non-BPS D-branes, K-theory has been shown to be the appropriate mathematical framework for classifying conserved D-brane charges. The classification accounts for known D-branes and predicts some new ones including a D8-brane in type I superstring theory. After briefly reviewing these developments, we discuss ce

  78. S. Ying

    A relativistic quantum field theory is presented for finite density problems based on the principle of locality. It is found that, in addition to the conventional ones, a local approach to the relativistic quantum field theories at both zero and finite density consistent with the violation of Bell like inequalities should contain, and provide solutions to at

  79. Amir Mulic

    In this note we display an observation about the geometrical properties of the gauge group manifold of the standard electroweak theory, and the values of the gauge coupling constants. Heuristically obtained stucture relates the value 137.036... to the low energy U(1) coupling. The constuction resembles techniques recently used within the framework of the str

  80. Vo Van Thuan

    Based on the dual principle in super-luminous Lorentz transformation this work shows that pseudo-spin of a time-like bradyon appears to space-like observers as iso-spin of a corresponding tachyon. Due to the weak interaction, lepton-tachyon appears as neutrino with hidden imaginary transcendent mass, suppressed by a factor of $ρ\sim G_F m^2_0$ compared to th

  81. Michael Gronau

    This is a quick review of CP non-conservation in $B$ physics. Several methods are described for testing the Kobayashi-Maskawa single phase origin of CP violation in B decays, pointing out some limitations due to hadronic uncertainties. A few characteristic signatures of new physics in B decay asymmetries are listed.

  82. Robert Fleischer

    Several new strategies to extract CKM phases, including a determination of $γ$ from $B_{s(d)}\to J/ψK_S$ decays and a general approach, which makes use of the angular distributions of certain $B_{d,s}$ modes, such as $B_d\to J/ψρ^0$ and $B_s\to J/ψϕ$, are discussed. Special emphasis is put on a simultaneous determination of $β$ and $γ$ with the help of the d

  83. Robert Fleischer

    After a brief review of the present status of the standard methods to extract CKM phases from CP-violating effects in non-leptonic B-decays, an overview of recent theoretical developments in this field is given, including extractions of $γ$ from $B\toπK$ and $B_{s(d)}\to J/ψK_S$ decays, a simultaneous determination of $β$ and $γ$, which is provided by the mo

  84. H. Satz

    We first consider the origin of colour deconfinement, comparing in particular spontaneous symmetry breaking and percolation. Next we specify the onset of deconfinement in nuclear collisions through parton percolation, and with parameters determined at SPS energy, we give quantitative predictions for charmonium suppression at RHIC. Finally we show that the pa

  85. L. M. Sehgal

    I review the theoretical basis of the prediction that the decay K_L -> pi+ pi- e+ e- should show a large CP- and T-violation, a prediction now confirmed by the KTeV experiment. The genesis of the effect lies in a large violation of CP- and T-invariance in the decay K_L -> pi+ pi- gamma, which is encrypted in the polarization state of the photon. The decay K_

  86. A. V. Belitsky, D. Müller, L. Niedermeier, A. Schäfer

    We study the amplitude of deeply virtual Compton scattering in next-to-leading order of perturbation theory including the two-loop evolution effects for different sets of skewed parton distributions (SPDs). It turns out that in the minimal subtraction scheme the relative radiative corrections are of order 20-50%. We analyze the dependence of our predictions

  87. George Japaridze, Wolf-Dieter Nowak, Avto Tkabladze

    We investigate $J/ψ$ photoproduction asymmetries in the framework of the NRQCD factorization approach. It is shown that the color octet contribution leads to large uncertainties in the predicted asymmetries which rules out the possibility to precisely measure the gluon polarization in the nucleon through this final state. For small values of the color octet

  88. Martin Lemoine

    We calculate the number density of helicity $\pm3/2$ gravitinos produced out of the vacuum by the non-static gravitational field in a generic inflation scenario. We compare it to the number density of gravitinos produced in particle interactions during reheating.

  89. K. Naito, Y. Nemoto, M. Takizawa, K. Yoshida

    U_A(1) symmetry breaking is studied by introducing the flavor mixing interaction proposed by Kobayashi, Maskawa and &#39;t Hooft. Combining the one gluon exchange interaction, the rainbow like Schwinger-Dyson equation and the ladder like Bethe-Salpeter equation are derived. The anomalous PCAC relation in the framework of this approximation is considered. The

  90. Hael Collins, Aaron K. Grant, Howard Georgi

    The top quark seesaw mechanism offers a method for constructing a composite Higgs field without the usual difficulties that accompany traditional technicolor or topcolor theories. The focus of this article is to study the phenomenology of the new physics required by this mechanism. After establishing a set of criteria for a plausible top quark seesaw theory,

  91. M. Heyssler, R. Ruckl, H. Spiesberger

    Pair production of leptoquarks at future e+e- linear colliders is investigated for center-of-mass energies of 500 GeV and 800 GeV and an integrated luminosity of 500 fb^-1. Based on a Monte Carlo simulation we estimate the event rates for signal as well as background processes and evaluate the discovery potential. As an example of virtual effects we consider

  92. W. Bietenholz, I. Hip

    We test exact and approximate Ginsparg-Wilson fermions with respect to their chiral and scaling behavior in the 2-flavor Schwinger model. We first consider explicit approximate GW fermions in a short range, then we proceed to their chiral correction by means of the ``overlap formula&#39;&#39;, and finally we discuss a numerically efficient perturbative chira

  93. V. L. Rykov

    Just in months ahead, the first high luminosity collisions of two polarized proton beams are expected to occur at RHIC in BNL at sqrt{s} up to 500 GeV, bringing a new quality to the collider physics. In collisions of polarized particles, the presence of two axial vectors of initial polarizations, fully controlled by experimenters, may dramatically increase t

  94. William G. Laarakkers, Eric Poisson

    This two-part contribution to the Proceedings of the Eighth Canadian Conference on General Relativity and Relativistic Astrophysics is devoted to the evolution of a massless scalar field in two black-hole spacetimes which are not asymptotically flat. In Part I (authored by Eric Poisson) we consider the evolution of a scalar field propagating in Schwarzschild

  95. G. L. Comer, David Langlois, Lap Ming Lin

    We develop a general formalism to treat, in general relativity, the linear oscillations of a two-fluid star about static (non-rotating) configurations. Such a formalism is intended for neutron stars, whose matter content can be described, as a first approximation, by a two-fluid model: one fluid is the neutron superfluid, which is believed to exist in the co

  96. Dahlia Malkhi, Michael Reiter, Avishai Wool

    Replicated services accessed via {\em quorums} enable each access to be performed at only a subset (quorum) of the servers, and achieve consistency across accesses by requiring any two quorums to intersect. Recently, $b$-masking quorum systems, whose intersections contain at least $2b+1$ servers, have been proposed to construct replicated services tolerant o

  97. Dahlia Malkhi, Yishay Mansour, Michael Reiter

    We study how to efficiently diffuse updates to a large distributed system of data replicas, some of which may exhibit arbitrary (Byzantine) failures. We assume that strictly fewer than $t$ replicas fail, and that each update is initially received by at least $t$ correct replicas. The goal is to diffuse each update to all correct replicas while ensuring that

  98. Dahlia Malkhi, Michael Reiter

    Mobile code presents a number of threats to machines that execute it. We introduce an approach for protecting machines and the resources they hold from mobile code, and describe a system based on our approach for protecting host machines from Java 1.1 applets. In our approach, each Java applet downloaded to the protected domain is rerouted to a dedicated mac

  99. Dahlia Malkhi, Michael Merritt, Ohad Rodeh

    A secure reliable multicast protocol enables a process to send a message to a group of recipients such that all correct destinations receive the same message, despite the malicious efforts of fewer than a third of the total number of processes, including the sender. This has been sh own to be a useful tool in building secure distributed services, albeit with

  100. George F. Bertsch, Thomas Papenbrock

    We compute numerically the yrast line for harmonically trapped boson systems with a weak repulsive contact interaction, studying the transition to a vortex state as the angular momentum L increases and approaches N, the number of bosons. The L=N eigenstate is indeed dominated by particles with unit angular momentum, but the state has other significant compon