Research archive

arXiv papers from July 2006

The most recent 100 records published that month. Open any paper for its original abstract, citation metadata, related research, and reading tools.

  1. Masanori Sato

    The transient phenomena of the Mach-Zender interferometer are discussed. To test the non-locality hypothesis, a single mode laser with a large coherence length is used. The behavior of a photon and its wave packets in the paths of the interferometer are discussed. Coherent photons have wave packets that overlap, thus their interference pattern is influenced

  2. The BABAR Collaboration, B. Aubert

    We report a measurement of CP-violating asymmetries in $B^0\to(\rho\pi)^0\to\pi^+\pi^-\pi^0$ decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 347 million $\Upsilon(4S) \to B\bar{B}$ decays, collected by the BaBar detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure 26 coefficients of the bil

  3. Pavel Etingof, Igor Pak

    We present a new algebraic extension of the classical MacMahon Master Theorem. The basis of our extension is the Koszul duality for non-quadratic algebras defined by Berger. Combinatorial implications are also discussed.

  4. Yitwah Cheung, Alex Eskin

    This preliminary report contains a sketch of the proof of the following result: a slowly divergent Teichmuller geodesic satisfying a certain logarithmic law is determined by a uniquely ergodic measured foliation.

  5. Christopher J. Hillar, Troels Windfeldt

    Let $K$ be a field, and let $R = K[X]$ be the polynomial ring in an infinite collection $X$ of indeterminates over $K$. Let ${\mathfrak S}_{X}$ be the symmetric group of $X$. The group ${\mathfrak S}_{X}$ acts naturally on $R$, and this in turn gives $R$ the structure of a left module over the (left) group ring $R[{\mathfrak S}_{X}]$. A recent theorem of Asc

  6. Yitwah Cheung

    In this paper we compute the Hausdorff dimension of the set D_n of points on divergent trajectories of the homogeneous flow induced by a certain one-parameter subgroup of G=SL(2,R) acting by left multiplication on the product space G^n/Gamma^n, where Gamma=SL(2,Z). We prove that the Hausdorff dimension of D_n equals 3n-(1/2) for any n greater than one.

  7. T. Garidi, J-P. Gazeau, S. Rouhani, M. V. Takook

    In the present work the massless vector field in the de Sitter (dS) space has been quantized. "Massless" is used here by reference to conformal invariance and propagation on the dS light-cone whereas "massive" refers to those dS fields which contract at zero curvature unambiguously to massive fields in Minkowski space. Due to the gauge invariance of the mass

  8. Dan A. Lee, Robert Lipshitz

    Heegaard Floer homology, first introduced by P. Ozsvath and Z. Szabo, associates to a 3-manifold Y a family of relatively graded Abelian groups HF(Y,t), indexed by Spin^c structures t on Y. In the case that Y is a rational homology sphere, Ozsvath and Szabo lift the relative Z-grading to an absolute Q-grading. This induces a relative Q-grading on \bigoplus_{

  9. Kevin Graham, Anatoly Konechny, Joerg Teschner

    We discuss how to describe time-dependent phenomena in string theory like the decay of unstable D-branes with the help of the world-sheet formulation. It is shown in a nontrivial well-controlled example that the coupling of the tachyons to propagating on-shell modes which escape to infinity can lead to time-dependent relaxation into a stationary final state.

  10. Linhua Jiang, Xiaohui Fan, Dean C. Hines, Yong Shi

    We present Spitzer observations of thirteen z~6 quasars using the Infrared Array Camera (IRAC) and Multiband Imaging Photometer for Spitzer (MIPS). All the quasars except SDSS J000552.34-000655.8 (SDSS J0005-0006) were detected with high S/N in the four IRAC channels and the MIPS 24um band, while SDSS J0005-0006 was marginally detected in the IRAC 8.0um band

  11. Aaron V. B. Arellano, Francisco S. N. Lobo

    In this work, we explore the possibility of evolving (2+1) and (3+1)-dimensional wormhole spacetimes, conformally related to the respective static geometries, within the context of nonlinear electrodynamics. For the (3+1)-dimensional spacetime, it is found that the Einstein field equation imposes a contracting wormhole solution and the obedience of the weak

  12. Miguel Mostafa

    The Pierre Auger Observatory detects ultra-high energy cosmic rays by implementing two complementary air-shower techniques. The combination of a large ground array and fluorescence detectors, known as the "hybrid" concept, means that a rich variety of measurements can be made on a single shower, providing much improved information over what is possible with

  13. Chun-Hsien Wu, Kin-Wang Ng, L. H. Ford

    We discuss the effect of quantum stress tensor fluctuations in deSitter spacetime upon the expansion of a congruence of timelike geodesics. We treat a model in which the expansion fluctuations begin on a given hypersurface in deSitter spacetime, and find that this effect tends to grow, in contrast to the situation in flat spacetime. This growth potentially l

  14. Rowan Killip, Mihai Stoiciu

    We study CMV matrices (a discrete one-dimensional Dirac-type operator) with random decaying coefficients. Under mild assumptions we identify the local eigenvalue statistics in the natural scaling limit. For rapidly decreasing coefficients, the eigenvalues have rigid spacing (like the numerals on a clock); in the case of slow decrease, the eigenvalues are dis

  15. Hiroki Suyari, Tatsuaki Wada

    We derive a scaling property from a fundamental nonlinear differential equation whose solution is the so-called q-exponential function. A scaling property has been believed to be given by a power function only, but actually more general expression for the scaling property is found to be a solution of the above fundamental nonlinear differential equation. In

  16. Lia Leon Chachanidze-Margolin, Shalva Tsiklauri

    The kinematical rotations of N-partical Hyperspherical basis are considered. The recurrence relation method of determination of transformation coefficients for arbitrary N-values is demonstrated.

  17. Simin Feng, Klaus Halterman, Pamela L. Overfelt

    We demonstrate that under certain conditions, fractional Talbot revivals can occur in heterostructures of composite metamaterials, such as multilayer positive and negative index media, metallodielectric stacks, and one-dimensional dielectric photonic crystals. Most importantly, without using the paraxial approximation we obtain Talbot images for the feature

  18. Alireza Saffarzadeh, Ali A. Shokri

    Using a quantum theory including spin-splitting effect in diluted magnetic semiconductors, we study the dependence of tunneling magnetoresistance (TMR) on barrier thickness, temperature and applied voltage in GaMnAs/GaAs/GaMnAs heterostructures. TMR ratios more than 65% are obtained at zero temperature, when one GaAs monolayer ($\approx$ 0.565 nm) is used as

  19. Krisztian Peters

    Most of the physics analyses at a hadron collider rely on a precise measurement of the energy of jets in the final state. This requires a precise in situ calibration of the calorimeter with the final detector setup. We present the basic procedure and results of the in situ gain calibration of the D0 HCAL in Run II. The gain calibration works on top of the pu

  20. C. A. Bonin, J. T. Lunardi, L. A. Manzoni, B. M. Pimentel

    This paper has been withdrawn by the authors

  21. Marcin Jankiewicz, Thomas W. Kephart

    We show interesting relations between extremal partition functions of a family of conformal field theories and dimensions of the irreducible representations of the Fischer-Griess Monster sporadic group. We argue that these relations can be interpreted as an extension of Monster moonshine.

  22. Geoffrey C. Bower, W. M. Goss, Heino Falcke, Donald C. Backer

    We present new high-resolution observations of Sagittarius A* at wavelengths of 17.4 to 23.8 cm with the Very Large Array in A configuration with the Pie Town Very Long Baseline Array antenna. We use the measured sizes to calibrate the interstellar scattering law and find that the major axis size of the scattering law is smaller by ~6% than previous estimate

  23. Jan O. Haerter, Michael R. Peterson, B. Sriram Shastry

    We present a finite temperature ($T$) study of the t-J model on the two-dimensional triangular lattice for the negative hopping $t$, as relevant for the electron-doped Na$_x$CoO$_2$ (NCO). To understand several aspects of this system, we study the $T$-dependent chemical potential, specific heat, magnetic susceptibility, and the dynamic Hall-coefficient acros

  24. D. S. Denisov, N. V. Mokhov, S. I. Striganov, M. A. Kostin

    With a multi-stage collimation system and magnetic iron spoilers in the tunnel, the background particle fluxes on the ILC detector can be substantially reduced. At the same time, beam-halo interactions with collimators and protective masks in the beam delivery system create fluxes of muons and other secondary particles which can still exceed the tolerable le

  25. Xiongfeng Ma

    By simulating four quantum key distribution (QKD) experiments and analyzing one decoy-state QKD experiment, we compare two data post-processing schemes based on security against individual attack by L\"{u}tkenhaus, and unconditional security analysis by Gottesman-Lo-L\"{u}tkenhaus-Preskill. Our results show that these two schemes yield close performances. Si

  26. J. Pittler, W. Bu, D. Vaknin, A. Travesset

    Anionic DMPA monolayers spread on LaCl$_3$ solutions reveal strong cation adsorption and a sharp transition to surface overcharging at unexpectedly low bulk salt concentrations. We determine the surface accumulation of La$^{3+}$ with anomalous x-ray reflectivity and find that La$^{3+}$ compensates the lipid surface charge by forming a Stern layer with $\appr

  27. Paata Kakashvili, Henrik Johannesson, Sebastian Eggert

    We calculate the finite-temperature local spectral weight (LSW) of a Luttinger liquid with an "open" (hard wall) boundary. Close to the boundary the LSW exhibits characteristic oscillations indicative of spin-charge separation. The line shape of the LSW is also found to have a Fano-like asymmetry, a feature originating from the interplay between electron-ele

  28. B. T. Draine, Aigen Li

    Infrared (IR) emission spectra are calculated for dust composed of mixtures of amorphous silicate and graphitic grains, including varying amounts of polycyclic aromatic hydrocarbon (PAH) particles. The models are constrained to reproduce the average Milky Way extinction curve. The calculations include the effects of single-photon heating. Updated IR absorpti

  29. A. Trionfi, S. Lee, D. Natelson

    In cold, mesoscopic conductors, two-level fluctuators lead to time-dependent universal conductance fluctuations (TDUCF) manifested as $1/f$ noise. In Au nanowires, we measure the magnetic field dependence of TDUCF, weak localization (WL), and magnetic field-driven (MF) UCF before and after treatments that alter magnetic scattering and passivate surface fluct

  30. S. R. Pottasch, J. Bernard-Salas

    A summary is given of planetary nebulae abundances from ISO measurements. It is shown that these nebulae show abundance gradients (with galactocentric distance), which in the case of neon, argon, sulfur and oxygen (with four exceptions) are the same as HII regions and early type star abundance gradients. The abundance of these elements predicted from these g

  31. Mirjam Cvetic, Paul Langacker

    We construct new supersymmetric SU(5) Grand Unified Models based on Z4 x Z2 orientifolds with intersecting D6-branes. Unlike constructions based on Z2 x Z2 orientifolds, the orbifold images of the three-cycles wrapped by D6-branes correspond to new configurations and thus allow for models in which, in addition to the chiral sector in 10 and 5-bar representat

  32. The BABAR Collaboration, B. Aubert

    Branching fraction and asymmetry measurements of charmless $B^+\to K^{*+}h^+_1h^-_2$ (where $h_{1,2}$ = $K$, $\pi$) decays are presented, using a data sample of 232 million $\Upsilon(4S) \to$ $BB$ decays collected with the BaBar detector at the SLAC PEP-II asymmetric-energy $B$ factory. Using a maximum likelihood fit, the following branching fraction results

  33. Sucharit Sarkar, Jiajun Wang

    In this paper, we give an algorithm to compute the hat version of the Heegaard Floer homology of a closed oriented three-manifold. This method also allows us to compute the filtrations coming from a null-homologous link in a three-manifold.

  34. E. Boulat, P. Mehta, N. Andrei, E. Shimshoni

    We study the low-temperature heat transport in clean two-leg spin ladder compounds coupled to three-dimensional phonons. We argue that the very large heat conductivities observed in such systems can be traced back to the existence of approximate symmetries and corresponding weakly violated conservation laws of the effective (gapful) low--energy model, namely

  35. Yi Hu

    We show that the moduli space of stable n-pointed rational curves can be flatly degenerated to a projective toric variety. We arrive at this by showing that the Chow quotients of the Grassmannians admit toric degenerations, which in turn, follows from a theorem that we prove for toric degenerations of more general Chow quotients. Along the way, we also argue

  36. The BABAR Collaboration, B. Aubert

    We present a preliminary measurement of CP-violation parameters in the decay B0 -> K+K-K0, using approximately 347 million BBbar events collected by the BABAR detector at SLAC. Reconstructing the neutral kaon as KS -> pi+pi-, KS -> pi0pi0, or KL, we analyze the Dalitz plot distribution and measure fractions to intermediate states. We extract CP parameters fr

  37. The BABAR Collaboration, B. Aubert

    We report measurements of the inclusive electron momentum spectra in decays of charged and neutral B mesons, and of the ratio of semileptonic branching fractions ${\cal B}\xspace(\B^+ \to X e \nu)$ and ${\cal B}\xspace(\B^0 \to X e \nu)$. These were performed on a sample of 231 million $B\kern 0.18em\bar{\kern -0.18em B}{}\xspace$ events recorded with the \m

  38. T. Rozek, D. Grzonka, H. -H. Adam, A. Budzanowski

    Sigma+ hyperon production was measured at the COSY-11 spectrometer via the p p --> n K+ Sigma+ reaction at excess energies of Q = 13 MeV and Q = 60 MeV. These measurements continue systematic hyperon production studies via the p p --> p K+ Lambda/Sigma0 reactions where a strong decrease of the cross section ratio close-to-threshold was observed. In order to

  39. John B. Etnyre

    In this note we observe, answering a question of Eliashberg and Thurston, that all contact structures on a closed oriented 3-manifold are $C^\infty$-deformations of foliations.

  40. A. D. Kennedy

    This is the write-up of three lectures on algorithms for dynamical fermions that were given at the ILFTN workshop 'Perspectives in Lattice QCD' in Nara during November 2005. The first lecture is on the fundamentals of Markov Chain Monte Carlo methods and introduces the Hybrid Monte Carlo (HMC) algorithm and symplectic integrators; the second lecture covers t

  41. Yusuke Nishida, Dam Thanh Son

    We construct systematic expansions around four and two spatial dimensions for a Fermi gas near the unitarity limit. Near four spatial dimensions such a Fermi gas can be understood as a weakly interacting system of fermionic and bosonic degrees of freedom. To the leading and next-to-leading orders in the expansion over epsilon=4-d, with d being the dimensiona

  42. Latha Venkataraman, Jennifer E. Klare, Colin Nuckolls, Mark S. Hybertsen

    The conductance of a single metal-molecule-metal junction depends critically on the conformations of the molecule. In the simple case of a biphenyl, two phenyl rings linked together by a single C-C bond, the conductance is expected to depend on the relative twist angle between the two rings, with the planar conformation having the highest conductance. A numb

  43. Alexander Khodjamirian

    The problem of hadronic input in charmless nonleptonic B decays is discussed. QCD sum rules and their light-cone versions (LCSR) provide an important part of this input, such as the decay constant $f_B$ and $B\to \pi$ form factor. Employing the LCSR technique, the $B\to \pi\pi$ hadronic matrix elements with emission, penguin and annihilation topologies are c

  44. M. Bender, P. Bonche, P. -H. Heenen

    We discuss shape coexistence in the neutron-deficient Kr72-Kr78 isotopes in the framework of configuration mixing calculations of particle-number and angular-momentum projected axial mean-field states obtained from self-consistent calculations with the Skyrme interaction SLy6 and a density-dependent pairing interaction. While our calculation reproduces quali

  45. Steve Blanchet, Pasquale Di Bari

    Flavor effects in leptogenesis reduce the region of the see-saw parameter space where the final predictions do not depend on the initial conditions, the strong wash-out regime. In this case we show that the lowest bounds holding on the lightest right-handed (RH) neutrino mass and on the reheating temperature for hierarchical heavy neutrinos, do not get relax

  46. Jonathan L. Rosner

    A definite relative phase and amplitude exists between the doubly-Cabibbo-% suppressed amplitude for $D^0 \to \ko M^0$ and the Cabibbo-favored amplitude for $D^0 \to \ok M^0$, where $M^0 = (\pi^0,\eta,\eta')$: $A(D^0 \to \ko M^0) = - \tan^2 \theta_C A(D^0 \to \ok M^0)$. Here $\theta_C$ is the Cabibbo angle. This relation, although previously recognized (for

  47. Gautam Rupak, Thomas Schaefer, Andrei Kryjevski

    We consider a polarized Fermi gas in the unitarity limit. Results are calculated analytically up to next-to-leading order in an expansion about d=4 spatial dimensions. We find a first order transition from superfluid to normal phase. The critical chemical potential asymmetry for this phase transition is delta_mu_c= 2/(mu epsilon)*(1-0.467\epsilon), where eps

  48. Yannis Bakopoulos, Theophanis Raptis, Doxaras Ioannis

    The Divider set, as an innovative alternative concept to maximal disks, Voronoi sets and cut loci, is presented with a formal definition based on topology and differential geometry. The relevant mathematical theory by previous authors and a comparison with other medial axis definitions is presented. Appropriate applications are proposed and examined.

  49. L. L. Bonilla, A. Carpio, J. C. Neu, W. G. Wolfer

    The formation and growth of helium bubbles due to self-irradiation in plutonium has been modelled by a discrete kinetic equations for the number densities of bubbles having $k$ atoms. Analysis of these equations shows that the bubble size distribution function can be approximated by a composite of: (i) the solution of partial differential equations describin

  50. D. A. Mazurenko, X. Shan, J. C. P. Stiefelhagen, C. M. Graf

    Coherent acoustic radial oscillations of thin spherical gold shells of submicron diameter excited by an ultrashort optical pulse are observed in the form of pronounced modulations of the transient reflectivity on a subnanosecond time scale. Strong acousto-optical coupling in a photonic crystal enhances the modulation of the transient reflectivity up to 4%. T

  51. Jonathan E. Moussa, Marvin L. Cohen

    Two simple bounds on the $T_c$ of conventional, phonon-mediated superconductors are derived within the framework of Eliashberg theory in the strong coupling regime. The first bound is set by the total electron-phonon coupling available within a material given the hypothetical ability to arbitrarily dope the material. This bound is studied by deriving a gener

  52. Nestor Armesto, Larry McLerran, Carlos Pajares

    We discuss forward-backward correlations in the mutliplicity of produced particles in heavy ion collisions. We find the Color Glass Condensate generates distinctive predictions for the long range component of this correlation. In particular, we predict the growth of the long range correlation with the centrality of the collision. We argue that the correlatio

  53. Charles F. Dunkl

    There is a commutative algebra of differential-difference operators, acting on polynomials on R_2, associated with the reflection group B2. This paper presents an integral transform which intertwines this algebra, allowing one free parameter, with the algebra of partial derivatives. The method of proof depends on properties of a certain class of balanced ter

  54. Marcelo O Terra Cunha, Vlatko Vedral

    We review how to obtain spin entangled pairs of fermions from a Fermi gas. An experiment with neutrons is proposed in order to get such pairs.

  55. C. Konar, D. J. Saikia, M. Jamrozy, J. Machalski

    We present new radio observations at frequencies ranging from 240 to 4860 MHz of the well-known, double-double radio galaxy (DDRG), J1453+3308, using both the Giant Metrewave Radio Telescope (GMRT) and the Very Large Array (VLA). These observations enable us to determine the spectra of the inner and outer lobes over a large frequency range and demonstrate th

  56. Nagalakshmi A Rao, B. A. Kagali

    While Klein paradox is often encountered in the context of scattering of relativistic particles at a potential barrier, we presently discuss a puzzling situation that arises with the Klein-Gordon equation for bound states. With the usual minimal coupling procedure of introducing the interaction potential, a paradoxical situation arises when the 'hill' become

  57. J. A. O. Matos, S. M. A. Gama, H. J. Ruskin, A. Sharkasi

    We use a new method of studying the Hurst exponent with time and scale dependency. This new approach allow us to recover the major events affecting worldwide markets (such as the September 11th terrorist attack) and analyze the way those effects propagate through the different scales. The time-scale dependence of the referred measures demonstrates the releva

  58. Glauber T. Silva

    The present study concerns the dynamic radiation force on solid elastic spheres exerted by a plane wave with two frequencies (bichromatic wave) considering the nonlinearity of the fluid. Our approach is based on solving the wave scattering for the sphere in the quasilinear approximation within the preshock wave range. The dynamic radiation force is then obta

  59. J. Bourassa, B. Roostaei, R. Cote, H. A. Fertig

    Recent experiments on strongly correlated bilayer quantum Hall systems strongly suggest that, contrary to the usual assumption, the electron spin degree of freedom is not completely frozen either in the quantum Hall or in the compressibles states that occur at filling factor $\nu =1.$ These experiments imply that the quasiparticles at $\nu =1$ could have bot

  60. Steffen Bohn, Marcelo O. Magnasco

    We minimize the dissipation rate of an electrical network under a global constraint on the sum of powers of the conductances. We construct the explicit scaling relation between currents and conductances, and show equivalence to a a previous model [J. R. Banavar {\it et al} Phys. Rev. Lett. {\bf 84}, 004745 (2000)] optimizing a power-law cost function in an a

  61. V. V. Shokurov

    To construct a resulting model in LMMP is sufficient to prove existence of log flips and their termination for certain sequences. We prove that LMMP in dimension $d-1$ and termination of terminal log flips in dimension $d$ imply, for any log pair of dimension $d$, the existence of a {\em resulting} log model: a strictly log minimal model or a strictly log te

  62. Tim D. Austin, Itai Benjamini

    For any initial configuration of fewer than N/2 cars the BML model will self organize to attain speed one. On the other hand, there is a configuration of size m in which no car can move if and only if m is at least 2N.

  63. Y. Nakajima, H. Shishido, H. Nakai, T. Shibauch

    We present a systematic study of the dc-resistivity, Hall effect, and magnetoresistance in the normal state of quasi 2D heavy fermion superconductors CeMIn5 (M: Rh and Co) under pressure. Here the electronic system evolves with pressure from an antiferromagnetic (AF) metal, through a highly unconventional non-Fermi liquid, and finally into a Fermi-liquid sta

  64. Andrea Passamonti

    This thesis investigates in the time domain a particular class of second order perturbations of a perfect fluid non-rotating compact star: those arising from the coupling between first order radial and non-radial perturbations. This problem has been treated by developing a gauge invariant formalism based on the 2-parameter perturbation theory (Sopuerta, Brun

  65. Florentin Smarandache, Jean Dezert

    This paper introduces the notion of qualitative belief assignment to model beliefs of human experts expressed in natural language (with linguistic labels). We show how qualitative beliefs can be efficiently combined using an extension of Dezert-Smarandache Theory (DSmT) of plausible and paradoxical quantitative reasoning to qualitative reasoning. We propose

  66. P. Deuar, P. D. Drummond

    The quantum dynamics of colliding Bose-Einstein condensates with 150 000 atoms are simulated directly from the Hamiltonian using the stochastic positive-P method. Two-body correlations between the scattered atoms and their velocity distribution are found for experimentally accessible parameters. Hanbury Brown-Twiss or thermal-like correlations are seen for c

  67. The BABAR Collaboration, B. Aubert

    We report on a search for the rare decay modes $B^+\to e^+ \nu_e$ and $B^+\to \mu^+ \nu_\mu$ with data collected from the BaBar detector at the PEP-II $e^+e^-$ storage ring. This search utilizes a new technique in which we fully reconstruct the accompanying $B^-$ in $\Upsilon(4S)\righarrow B^+ B^-$ events, and look for a mono-energetic lepton in the $B^+$ re

  68. Jean-Luc Thiffeault, Khalid Kamhawi

    We consider steady gravity-driven flow of a thin layer of viscous fluid over a curved substrate. The substrate has topographical variations (`bumps') on a large scale compared to the layer thickness. Using lubrication theory, we find the velocity field in generalized curvilinear coordinates. We correct the velocity field so as to satisfy kinematic constraint

  69. Davide Lazzati

    Synchrotron is considered the dominant emission mechanism in the production of gamma-ray burst photons in the prompt as well as in the afterglow phase. Polarization is a characteristic feature of synchrotron and its study can reveal a wealth of information on the properties of the magnetic field and of the energy distribution in gamma-ray burst jets. In this

  70. Shing-Tung Yau

    This is lecture notes of a talk I gave at the Morningside Center of Mathematics on June 20, 2006. In this talk, I survey on Poincare and geometrization conjecture.

  71. Andre Joyal, Myles Tierney

    We show that complete Segal spaces and Segal categories are Quillen equivalent to quasi-categories.

  72. S. G. Ghosh, D. W. Deshkar

    The general solution of the Einstein equation for higher dimensional (HD) spherically symmetric collapse of inhomogeneous dust in presence of a cosmological term, i.e., exact interior solutions of the Einstein field equations is presented for the HD Tolman-Bondi metrics imbedded in a de Sitter background. The solution is then matched to exterior HD Scwarschi

  73. Y. Miroshnychenko, W. Alt, I. Dotsenko, L. Förster

    We have recently demonstrated the creation of regular strings of neutral caesium atoms in a standing wave optical dipole trap using optical tweezers [Y. Miroshnychenko et al., Nature, in press (2006)]. The rearrangement is realized atom-by-atom, extracting an atom and re-inserting it at the desired position with sub-micrometer resolution. We describe our exp

  74. Joseph Y. Halpern, Riccardo Pucella

    Logics for security protocol analysis require the formalization of an adversary model that specifies the capabilities of adversaries. A common model is the Dolev-Yao model, which considers only adversaries that can compose and replay messages, and decipher them with known keys. The Dolev-Yao model is a useful abstraction, but it suffers from some drawbacks:

  75. G. S. Agarwal, J. Banerji

    We consider the evolution of a two-mode system of bosons under the action of a Hamiltonian that generates linear SU(2) transformations. The Hamiltonian is generic in that it represents a host of entanglement mechanisms, which can thus be treated in a unified way. We start by solving the quantum dynamics analytically when the system is initially in a Fock sta

  76. M. Camarda, F. Siringo, R. Pucci, A. Sudbo

    The geometric properties of critical fluctuations in the 3D XY model are analyzed. The 3D XY model is a lattice model describing superfluids. We present a direct evaluation of the Hausdorff dimension D_H of the vortex loops which are the critical fluctuations of the 3D XY model. We also present analytical arguments for why \vartheta in the scaling relation \

  77. F. Calura, F. Matteucci

    We compute the type Ia, Ib/c and II supernova (SN) rates as functions of the cosmic time for galaxies of different morphological types. We use four different chemical evolution models, each one reproducing the features of a particular morphological type: E/S0, S0a/b, Sbc/d and Irr galaxies. We essentially describe the Hubble sequence by means of decreasing e

  78. F. Clementi, M. Gallegati, G. Kaniadakis

    Starting from the generalized exponential function $\exp_{\kappa}(x)=(\sqrt{1+\kappa^{2}x^{2}}+\kappa x)^{1/\kappa}$, with $\exp_{0}(x)=\exp(x)$, proposed in Ref. [G. Kaniadakis, Physica A \textbf{296}, 405 (2001)], the survival function $P_{>}(x)=\exp_{\kappa}(-\beta x^{\alpha})$, where $x\in\mathbf{R}^{+}$, $\alpha,\beta>0$, and $\kappa\in[0,1)$, is consid

  79. Thomas Holenstein

    Consider a game where a refereed a referee chooses (x,y) according to a publicly known distribution P_XY, sends x to Alice, and y to Bob. Without communicating with each other, Alice responds with a value "a" and Bob responds with a value "b". Alice and Bob jointly win if a publicly known predicate Q(x,y,a,b) holds. Let such a game be given and assume that t

  80. Frank Schuhmacher

    We prove explit formulas for the decomposition of a differential graded Lie algebra into a minimal and a linear $L_\infty$-algebra. We define a category of metric $L_\infty$-algebras, called Palamodov $L_\infty$ algebras, where the structure maps satisfy a certain convergence condition and deduce a decomposition theorem for differential graded Lie algebras i

  81. T. Hanney

    A general class of mass transport models with Q species of conserved mass is considered. The models are defined on a lattice with parallel discrete time update rules. For one-dimensional, totally asymmetric dynamics we derive necessary and sufficient conditions on the mass transfer dynamics under which the steady state factorises. We generalise the model to

  82. S. P. Willner, A. L. Coil, W. M. Goss, M. L. N. Ashby

    A new 6-cm survey of almost 0.6 square degrees to a limit of 0.55-mJy/beam (10-sigma) finds 37 isolated radio sources and 7 radio source pairs (not necessarily physical companions). IRAC counterparts are identified for at least 92% of the radio sources within the area of deep IRAC coverage, which includes 31 isolated sources and 6 pairs. This contrasts with

  83. Stanimir Andonov

    The sixth product level called compliant product is a connecting element between the physical product characteristics and the strategy of the producer company. The article discusses the differentiation among the product offers of companies working in the global markets, as well as the strategies which they use and could use in that respect.

  84. Daniel E. Sheehy, Leo Radzihovsky

    We study resonantly-paired s-wave superfluidity in a degenerate gas of two species (hyperfine states labeled by $\uparrow,\downarrow$) of fermionic atoms when the numbers $N_{\uparrow}$ and $N_{\downarrow}$ of the two species are {\it unequal}, i.e., the system is "polarized". We find that the continuous crossover from the Bose-Einstein condensate (BEC) limi

  85. I. M. Merhasin, Boris A. Malomed, Y. B. Band

    We construct families of incoherent matter-wave solitons in a repulsive degenerate Bose gas trapped in an optical lattice (OL), i.e., gap solitons, and investigate their stability at zero and finite temperature, using the Hartree-Fock-Bogoliubov equations. The gap solitons are composed of a coherent condensate, and normal and anomalous densities of incoheren

  86. Ivan V. Arzhantsev, Juergen Hausen

    Given a multigraded algebra $A$, it is a natural question whether or not for two homogeneous components $A_u$ and $A_v$, the product $A_{nu}A_{nv}$ is the whole component $A_{nu+nv}$ for $n$ big enough. We give combinatorial and geometric answers to this question.

  87. P. F. Harrison, W. G. Scott, T. J. Weiler

    In fermion mixing phenomenology, the matrix of moduli squared, P=(|U|^2), is well-known to carry essentially the same information as the complex mixing matrix U itself, but with the advantage of being phase-convention independent. The matrix K (analogous to the Jarlskog CP-invariant J) formed from the real parts of the mixing matrix "plaquette" products is s

  88. Mariano Lopez de Haro, Santos B. Yuste, Andres Santos

    Recent Monte Carlo simulation results for the contact values of polydisperse hard-sphere mixtures at a hard planar wall are considered in the light of a universality assumption made in approximate theoretical approaches. It is found that the data seem to fulfill the universality ansatz reasonably well, thus opening up the possibility of inferring properties

  89. Jean Dezert, Albena Tchamova, Florentin Smarandache, Pavlina Konstantinova

    In this paper we consider and analyze the behavior of two combinational rules for temporal (sequential) attribute data fusion for target type estimation. Our comparative analysis is based on Dempster's fusion rule proposed in Dempster-Shafer Theory (DST) and on the Proportional Conflict Redistribution rule no. 5 (PCR5) recently proposed in Dezert-Smarandache

  90. James Graber

    LISA may make it possible to test the black-hole uniqueness theorems of general relativity, also called the no-hair theorems, by Ryan's method of detecting the quadrupole moment of a black hole using high-mass-ratio inspirals. This test can be performed more robustly by observing inspirals in earlier stages, where the simplifications used in making inspiral

  91. M. N. Popescu, S. Dietrich, G. Oshanin

    We study the equilibrium properties of a model for a binary mixture of catalytically-reactive monomers adsorbed on a two-dimensional substrate decorated by randomly placed catalytic bonds. The interacting $A$ and $B$ monomer species undergo continuous exchanges with particle reservoirs and react ($A + B \to \emptyset$) as soon as a pair of unlike particles a

  92. T. L. Schmidt, A. Komnik, A. O. Gogolin

    We analyze the full counting statistics of charge transfer through a quantum dot in the Kondo regime, when coupled to an arbitrary number of terminals N. At the unitary Kondo fixed point and for N>2 we recover distinct anticorrelations of currents in concurring transport channels, which are related to the fermionic Hanbury Brown and Twiss (HBT) antibunching.

  93. B. Clarke, Ao Yuan

    Sample size criteria are often expressed in terms of the concentration of the posterior density, as controlled by some sort of error bound. Since this is done pre-experimentally, one can regard the posterior density as a function of the data. Thus, when a sample size criterion is formalized in terms of a functional of the posterior, its value is a random var

  94. Nicolai Kuntze, Dominique Maehler, Andreas U. Schmidt

    Reputation and recommendation systems are fundamental for the formation of community market places. Yet, they are easy targets for attacks which disturb a market's equilibrium and are often based on cheap pseudonyms used to submit ratings. We present a method to price ratings using trusted computing, based on pseudonymous tickets.

  95. B. Enriquez, G. Halbout

    We introduce the notion of Gamma-Lie bialgebra, where Gamma is a group. These objects give rise to cocommutative co-Poisson algebras, for which we construct quantization functors. This enlarges the class of co-Poisson algebras for which a quantization is known. Our result relies on our earlier work, where we showed that twists of Lie bialgebras can be quanti

  96. Klaus Kassner

    It is demonstrated that the description of surface-diffusion controlled dynamics via the phase-field method is less trivial than it appears at first sight. A seemingly straightforward approach previously used in the literature is shown to fail to produce the correct asymptotics, albeit in a subtle manner. An apparently obvious alternative fails for a complem

  97. Sophonie Blaise Tchapnda

    Some future global properties of cosmological solutions for the Einstein-Vlasov-Maxwell system with surface symmetry are presented. Global existence is proved, the homogeneous spacetimes are future complete for causal trajectories, and the same is true for inhomogeneous plane-symmetric solutions with small initial data. In the latter case some decay properti

  98. J. C. Phillips

    ARPES and wide area, high resolution STM studies of a micaceous cuprate high temperature superconductor have shown strong nanoscale gap disorder, but the question of whether this disorder is intrinsic and necessary for HTSC, or merely incidental to either this material, or even only its surface, appears to be an open one. We present the case that it is merel

  99. The BABAR Collaboration, B. Aubert

    We present an observation of $B\to\eta^\prime K^*$. The data sample corresponds to 232 million $B\bar{B}$ pairs collected with the BABAR detector at the PEP-II asymmetric-energy $B$ Factory at SLAC. We measure the branching fractions (in units of $10^{-6}$) $\mathcal{B}(B^0\to\eta^\prime K^{*0}) = 3.8\pm1.1\pm0.5$ and $\mathcal{B}(B^+\to\eta^\prime K^{*+}) =

  100. Félix Werner, Yvan Castin

    We consider N atoms trapped in an isotropic harmonic potential, with s-wave interactions of infinite scattering length. In the zero-range limit, we obtain several exact analytical results: mapping between the trapped problem and the free-space zero-energy problem, separability in hyperspherical coordinates, SO(2,1) hidden symmetry, and relations between the