August 2003 arXiv papers
Showing 1–100 of 2,790 papers
W. P. Bowen, R. Schnabel, P. K. Lam, T. C. Ralph
We present an experimental analysis of quadrature entanglement produced from a pair of amplitude squeezed beams. The correlation matrix of the state is characterized within a set of reasonable assumptions, and the strength of the entanglement is gauged using measures of the degree of inseparability and the degree of EPR paradox. We introduce controlled decoh
Nikolaos Tziolas
Revised version. Proper credits added. In this paper we study divisorial extremal neighborhoods f:Y-->X, such that X is a cAn type three dimensional terminal singularity, and C=f(E) is a smooth curve, where E is the f-exceptional divisor. We view a divisorial extremal neighborhood as a one-parameter smoothing of certain surface singularities, and based on th
Analytic non-supersymmetric background dual of a confining gauge theory and the corresponding plane wave theory of Hadrons
hep-thStanislav Kuperstein, Jacob Sonnenschein
We find a regular analytic 1st order deformation of the Klebanov-Strassler background. From the dual gauge theory point of view the deformation describes supersymmetry soft breaking gaugino mass terms. We calculate the difference in vacuum energies between the supersymmetric and the non-supersymmetric solutions and find that it matches the field theory predi
I. Krichever, A. Marshakov, A. Zabrodin
We study the integrable structure of the Dirichlet boundary problem in two dimensions and extend the approach to the case of planar multiply-connected domains. The solution to the Dirichlet boundary problem in multiply-connected case is given through a quasiclassical tau-function, which generalizes the tau-function of the dispersionless Toda hierarchy. It is
Increase of the Hawking radiation for spinor particles from Schwarzschild black holes by Dirac monopoles
astro-phYu. P. Goncharov, N. E. Firsova
An algorithm for numerical computation of the barrier transparency for the potentials surrounding Schwarzschild black holes is described for massless spinor particles. It is then applied to calculate the all configurations (including the contributions of twisted field configurations connected with Dirac monopoles) luminosity for the Hawking radiation from a
Gerald Schubert, Alexander Weisse, Gerhard Wellein, Holger Fehske
Taking into account that a proper description of disordered systems should focus on distribution functions, the authors develop a powerful numerical scheme for the determination of the probability distribution of the local density of states (LDOS), which is based on a Chebyshev expansion with kernel polynomial refinement and allows the study of large finite
K. A. Postnov, S. I. Blinnikov, D. I. Kosenko, E. I. Sorokina
Time-dependent thermal effects should accompany standard non-thermal afterglows of GRB when gamma-rays pass through inhomogeneous surroundings of the GRB site. Thermal relaxation of an optically thin plasma is calculated using time-dependent collisional ionization of the plasma ion species. X-ray emission lines are similar to those found in the fading X-ray
J. Balog, A. Hegedus
TBA integral equations are proposed for 1-particle states in the sausage- and SS-models and their $σ$-model limits. Combined with the ground state TBA equations the exact mass gap is computed in the O(3) and O(4) nonlinear $σ$-model and the results are compared to 3-loop perturbation theory and Monte Carlo data.
Shouchuan Zhang, Yanying Han
Let $H$ be an infinite-dimensional braided Hopf algebra and assume that the braiding is symmetric on $H$ and its quasi-dual $H^d$. We prove the Blattner-Montgomery duality theorem, namely we prove $$ (R # H)# H^{d} \cong R \otimes (H # H^{d}) \hbox {as algebras in braided tensor category} {\cal C}.$$ In particular, we present two duality theorems for infinit
G. Colo`, N. Van Giai
The status of the theoretical research on the compressional modes of finite nuclei and the incompressibility $K_\infty$ of nuclear matter, is reviewed. It is argued that the recent experimental data on the Isoscalar Giant Monopole Resonance (ISGMR) allow extracting the value of $K_\infty$ with an uncertainity of about $\pm$ 12 MeV. Non-relativistic (Skyrme,
Structure of pair winds from compact objects with application to emission from hot bare strange stars
astro-phA. G. Aksenov, M. Milgrom, V. V. Usov
We consider a stationary, spherically outflowing wind consisting of electron-positron pairs and photons. We do not assume thermal equilibrium, and include the two-body processes that occur in such a wind: Moller and Bhaba scattering of pairs, Compton scattering, two-photon pair annihilation, and two-photon pair production, together with their radiative three
Kaida Shi
By studying the n-dimensional cube, the author finds a new way, and use it to proves that the indefinite equation $x^n+y^n=z^n(n=>3)$ has no any solutions of positive integers.
Mario Stipčević
Non-deterministic random bits are needed in many scientific fields. Unfortunately today's computers are very limited in ability to produce them. We present here a method for extraction of non-deterministic random bits from random physics processes, and one practical realization of a physical generator based on it. The method is shown to deliver increasin
Jose P. Palao, R. Kosloff
The dynamics of a quantum system driven by an external field is well described by a unitary transformation generated by a time dependent Hamiltonian. The inverse problem of finding the field that generates a specific unitary transformation is the subject of study. The unitary transformation which can represent an algorithm in a quantum computation is imposed
Guillaume Adenier, Andrei Yu. Khrennikov
We propose here an experimental test of the fair sampling assumption in two-channel EPR-Bell experiments for which the detection loophole holds.
B. Sun, M. S. Chapman, L. You
We extend an earlier model by Law {\it et al.} \cite{law} for a cavity QED based single-photon-gun to atom-photon entanglement generation and distribution. We illuminate the importance of a small critical atom number on the fidelity of the proposed operation in the strong coupling limit. Our result points to a promisingly high purity and efficiency using cur
An Experimental Realization of Quantum-vacuum Geometric Phases by Using the Gyrotropic-medium Optical Fiber
quant-phJian Qi Shen
The connection between the quantum-vacuum geometric phases (which originates from the vacuum zero-point electromagnetic fluctuation) and the non-normal product procedure is considered in the present Letter. In order to investigate this physically interesting geometric phases at quantum-vacuum level, we suggest an experimentally feasible scheme to test it by
Hayato Goto, Haibo Wang, Tomoyuki Horikiri, Yasuo Yanagihara
Two-photon interference of multimode two-photon pairs produced by an optical parametric oscillator has been observed for the first time with an unbalanced interferometer. The time correlation between the multimode two photons has a multi-peaked structure. This property of the multimode two-photon state induces two-photon interference depending on delay time.
Development of a triple GEM UV-photon detector operated in pure CF4 for the PHENIX experiment
physics.ins-detA. Kozlov, I. Ravinovich, L. Shekhtman, Z. Fraenkel
Results obtained with a triple GEM detector operated in pure CF4 with and without a reflective CsI photocathode are presented. The detector operates in a stable mode at gains up to 10^4. A deviation from exponential growth starts to develop when the total charge exceeds ~ 4 10^6 e leading to gain saturation when the total charge is ~ 2 10^7 e and making the
Ahmad Moshaii, Rasool Sadighi-Bonabi, Mohammad Taeibi-Rahni
The non-linear bubble dynamics equations in a compressible liquid have been modified considering the effects of compressibility of both the liquid and the gas at the bubble interface. A new bubble boundary equation has been derived, which includes a new term resulted from the liquid bulk viscosity effects. The influence of this term has been numerically inve
C. Gorria, Yu. B. Gaididei, M. P. Soerensen, P. L. Christiansen
We consider the propagation of sine-Gordon kinks in a planar curved strip as a model of nonlinear wave propagation in curved wave guides. The homogeneous Neumann transverse boundary conditions, in the curvilinear coordinates, allow to assume a homogeneous kink solution. Using a simple collective variable approach based on the kink coordinate, we show that cu
M. C. Nucci
In (Nucci M.C. 1994, Physica D 78 p.124), we have found that iterations of the nonclassical symmetries method give rise to new nonlinear equations, which inherit the Lie point symmetry algebra of the given equation. In the present paper, we show that special solutions of the right-order heir-equation correspond to classical and nonclassical symmetries of the
O. V. Kaptsov, A. V. Schmidt
A construction of differential constraints compatible with partial differential equations is considered. Certain linear determining equations with parameters are used to find such differential constraints. They generalize the classical determining equations used in the search for admissible Lie operators. As applications of this approach non-linear heat equa
Itai Benjamini, Gady Kozma
Sharp estimates for the length of loop erased random walk between two vertices on the [n]^d -torus, d > 4, are established. The mean length is order n^{d/2} . In dimension 4 we have only an upper bound.
Bennett Chow, Richard Hamilton
We introduce a geometric evolution equation for 3-manifolds with sectional curvature of one sign which is in some sense dual to the Ricci flow. On a closed 3-manifold with negative sectional curvature, we establish short time existence and a pair of monotonicity formulas for solutions to the flow. One of these formulas shows that, provided the solution exist
Alexandru Ghitza
In a letter to Tate (published in Israel J. Math. in 1996), J.-P. Serre proves that the systems of Hecke eigenvalues given by modular forms (mod p) are the same as the ones given by locally constant functions on an adelic double coset space constructed from the endomorphism algebra of a supersingular elliptic curve. We generalize this result to Siegel modula
Guy Katriel
We present a proof of the Sturm-Hurwitz theorem, using basic calculus.
Calculation of Rozansky-Witten invariants on the Hilbert schemes of points on a K3 surface and the Generalised Kummer varieties
math.AGMarc A. Nieper-Wisskirchen
By showing a structural result on how the Rozansky-Witten invariants of Hilbert schemes of points on a K3 surface and the Generalised Kummer varieties depend on the dimension, we give a method how to compute a large class of Rozansky-Witten invariants in terms of Chern numbers.
R. Loll, W. Westra
It is well-known that the sum over topologies in quantum gravity is ill-defined, due to a super-exponential growth of the number of geometries as a function of the space-time volume, leading to a badly divergent gravitational path integral. Not even in dimension 2, where a non-perturbative quantum gravity theory can be constructed explicitly from a (regulari
Falk Bruckmann, Daniel Nogradi, Pierre van Baal
We review how instanton solutions at finite temperature can be seen as boundstates of constituent monopoles, discuss some speculations concerning their physical relevance and the lattice evidence for their presence in a dynamical context.
Dirac equation in the confining SU(3)-Yang-Mills field and the relativistic effects in quarkonia spectra
hep-phYu. P. Goncharov, E. A. Choban
The recently obtained solutions of Dirac equation in the confining SU(3)-Yang-Mills field in Minkowski spacetime are applied to describe the energy spectra of quarkonia (charmonium and bottomonium). The nonrelativistic limit is considered for the relativistic effects to be estimated in a self-consistent way and it is shown that the given effects are extremel
M. R. Schindler, J. Gegelia, S. Scherer
We formulate the infrared regularization of Becher and Leutwyler in a form analogous to our recently proposed extended on-mass-shell renormalization. In our formulation, IR regularization can be applied straightforwardly to multi-loop diagrams with an arbitrary number of particles with arbitrary masses.
Dirac equation in the confining SU(3)-Yang-Mills field and relativistic effects in charmonium spectrum
hep-phYu. P. Goncharov
The recently obtained solutions of the Dirac equation in the confining SU(3)-Yang-Mills field in Minkowski spacetime are applied to describe the energy spectrum of charmonium. The nonrelativistic limit is considered for the relativistic effects to be estimated in a self-consistent way and it is shown that the given effects could be extremely important for bo
Wei Zhu, Jian-hong Ruan, Ji-feng Yang, Zhen-qi Shen
Parton distributions in the small $x$ region are numerically predicted by using a modified DGLAP equation with the GRV-like input distributions. We find that gluon recombination at twist-4 level obviously suppresses the rapid growth of parton densities with $x$ decrease. We show that before the saturation scale $Q^2_s$ is reached, saturation and partial satu
Iain A. Bertram
Results are presented from analyses of jet data produced in pbarp collisions at $\sqrt{s}$ = 1960 GeV collected with the DZero and CDF detectors during 2002--03 at the Fermilab Tevatron Collider. Preliminary measurements of the inclusive jet cross section, the dijet mass spectrum, and jet structure are presented.
Michael Unger
The atmospheric muon spectrum between 20 and 2000 GeV was measured with the L3 magnetic muon spectrometer for zenith angles ranging from 0 to 58 degrees. Due to the large data set and the good detector resolution, a precision of 2.6% at 100 GeV was achieved for the absolute normalization of the vertical muon flux. The momentum dependence of the ratio of posi
D. J. Summers
We report the results of a blind search for flavor-changing neutral current (FCNC), lepton-flavor violating, and lepton-number violating decays of D+, Ds+, and D0 mesons (and their antiparticles) into 2-, 3-, and 4-body states including a lepton pair. Such decays may involve Flavor-Changing Neutral Currents, Leptoquarks, Horizontal Gauge Bosons, or Majorana
Esther M. Arkin, Michael A. Bender, Erik D. Demaine, Martin L. Demaine
We explore the following problem: given a collection of creases on a piece of paper, each assigned a folding direction of mountain or valley, is there a flat folding by a sequence of simple folds? There are several models of simple folds; the simplest one-layer simple fold rotates a portion of paper about a crease in the paper by +-180 degrees. We first cons
Direct observation of orbital ordering in La$_{0.5}$Sr$_{1.5}$MnO$_4$ using soft x-ray diffraction
cond-mat.str-elS. B. Wilkins, P. D. Spencer, P. D. Hatton, S. P. Collins
We report the first direct resonant soft x-ray scattering observations of orbital ordering. We have studied the low temperature phase of La$_{0.5}$Sr$_{1.5}$MnO$_4$, a compound that displays charge and orbital ordering. Previous claims of orbital ordering in such materials have relied on observations at the Manganese $K$ edge. These claims have been question
Alexei E. Koshelev
In very anisotropic layered superconductors a tilted magnetic field generates crossing vortex lattices of pancake and Josephson vortices (JVs). We study the properties of an isolated JV in the lattice of pancake vortices. JV induces deformations in the pancake vortex crystal, which, in turn, substantially modify the JV structure. The phase field of the JV is
Mai Suan Li
The present review is given on the paramagnetic Meissner effect observed in conventional and ceramic high-Tc superconductors. We discuss two mechanisms leading to this phenomenon: the d-wave and the flux compensation. It is shown that the chiral glass phase may occur in granular superconductors possessing d-wave pairing symmetry. Dynamical phenomena such as
Dependence of Empirical Fundamental Diagram on Spatial-Temporal Traffic Patterns Features
cond-mat.stat-mechBoris S. Kerner
It is shown that the branch of the empirical fundamental diagram for congested traffic strongly depends both on the type of the congested pattern at a freeway bottleneck and on the freeway location where the fundamental diagram is measured. Since the type of the pattern at the same bottleneck can depend on traffic demand, a qualitative form of the empirical
Boris S. Kerner
A microscopic theory of control of spatial-temporal congested traffic pattern at freeway bottlenecks is presented. Based on empirical spatial-temporal features of congested patterns at freeway bottlenecks which have recently been found, different control strategies for prevention or reducing of the patterns are simulated and compared. The studied control str
Nobuki Maeda
We study spin and charge striped states at the half-filled high Landau level in the zero Zeeman energy limit using a Hartree-Fock approximation. It is shown that a ferromagnetic striped Hall state is more stable than the antiferromagnetic striped state or charge striped state. We calculate the collective excitations using the single mode approximation.
N. Bernhoeft, J. A. Paixão, C. Detlefs, S. B. Wilkins
Using resonant x-ray scattering to perform diffraction experiments at the U M$_{4}$ edge novel reflections of the generic form $<kkk>$ have been observed in UAs$_{0.8}$Se$_{0.2}$ where $\vec{k} = < k00>$, with $k = {1/2}$ reciprocal lattice units, is the wave vector of the primary (magnetic) order parameter. The $<kkk>$ reflections, with $10^{-4}$ of the $<k
Duncan Forbes, Michael Beasley, Kenji Bekki, Jean Brodie
The relics of disrupted satellite galaxies around the Milky Way and Andromeda have been found, but direct evidence of a satellite galaxy in the early stages of being disrupted has remained elusive. We have discovered a dwarf satellite galaxy in the process of being torn apart by gravitational tidal forces as it merges with a larger galaxy's dark matter h
A. Finoguenov, U. G. Briel, J. P. Henry
XMM-Newton observations of the outskirts of the Coma cluster of galaxies confirm the existence of a soft X-ray excess claimed previously and show it comes from warm thermal emission. Our data provide a robust estimate of its temperature (~0.2 keV) and oxygen abundance (~0.1 solar). Using a combination of XMM-Newton and ROSAT All-Sky Survey data, we rule out
L. Deharveng, B. Lefloch, A. Zavagno, J. Caplan
We present millimetre-line imaging of the Galactic HII region Sh 104. We show that it is surrounded by a ring of molecular gas and dust. Four large molecular condensations are regularly spaced around the ring. These condensations are themselves fragmented and contain several massive dense cores. A deeply embedded cluster is observed in the near IR towards th
Probing the presence of a single or binary black hole in the globular cluster NGC 6752 with pulsar dynamics
astro-phMonica Colpi, Michela Mapelli, Andrea Possenti
The five millisecond pulsars that inhabit NGC 6752 display locations or accelerations that are quite unusual compared to all other pulsars known in globular clusters. In particular PSR-A, a binary pulsar, lives in the cluster halo, while PSR-B and PSR-E, located in the core, show remarkably high negative spin derivatives. This is suggestive that some uncommo
New Astrophysical Tests from the Einstein's Equivalence Principle and Gravitational Experiments
astro-phRafael A. Vera
The Einstein's equivalence principle and experiments, in which bodies and observers are in different G potentials, have been used to prove that the chain of hypothesis coming from assuming the absolute invariability of the bodies, after a change of G potential, are wrong. The absolute changes of frequencies, masses and lengths of every well-defined part
Anzhong Wang
Recently, the gravitational collapse of an infinite cylindrical thin shell of matter in an otherwise empty spacetime with two hypersurface orthogonal Killing vectors was studied by Gonçalves [Phys. Rev. {\bf D65}, 084045 (2002).]. By using three "alternative" criteria for trapped surfaces, the author claimed to have shown that {\em they can never for
V. Subrahmanyam
Entanglement sharing among pairs of spins in Heisenberg antiferromagnets is investigated using the concurrence measure. For a nondegenerate S=0 ground state, a simple formula relates the concurrence to the diagonal correlation function. The concurrence length is seen to be extremely short. A few finite clusters are studied numerically, to see the trend in hi
S. Fortunato, D. Stauffer, A. Coniglio
The number of spanning clusters in four to nine dimensions does not fully follow the expected size dependence for random percolation.
Piotr T. Chrusciel, Erwann Delay
We construct manifold structures on various sets of solutions of the general relativistic initial data sets.
R. Casana, V. Ya. Fainberg, B. M. Pimentel, J. S. Valverde
The thermodynamical partition function of the Duffin-Kemmer-Petiau theory is evaluated using the imaginary-time formalism of quantum field theory at finite temperature and path integral methods. The DKP partition function displays two features: (i) full equivalence with the partition function for charged scalar particles and charged massive spin 1 particles;
A. E. F. Djemai, H. Smail
In this work, we develop a general framework in which Noncommutative Quantum Mechanics (NCQM) is showed to be equivalent to Quantum Mechanics (QM) on a suitable transformed Quantum Phase Space (QPS). Imposing some constraints on this particular transformation, we firstly find that the product of the two noncommutativity parameters possesses a lower bound in
Jesus Martinez-Linares, Julio Vargas-Medina
A formalism have been recently derived [J. Martinez-Linares and D. Harmin, quantum-ph/0306057] allowing one to separate different sources of which-way information contributing to the total distinguishability D of the ways in a two-way interferometer. Here we apply the formalism to a Quantum Optical Ramsey Interferometer where both sources, the a-priori predi
Jesus Martinez-Linares, Julio Vargas-Medina
A scheme for an atomic beam quantum self-eraser is presented. The proposal is based on time reversal invariance on a quantum optical Ramsey fringes experiment, where a realization of complementarity for atomic coherence can be achieved. It consists of two high finesse resonators that are pumped and probed by the same atom. This property relates quantum erasi
Squeezed States of the Generalized Minimum Uncertainty State for the Caldirola-Kanai Hamiltonian
quant-phSang Pyo Kim
We show that the ground state of the well-known pseudo-stationary states for the Caldirola-Kanai Hamiltonian is a generalized minimum uncertainty state, which has the minimum allowed uncertainty $Δq Δp = \hbar σ_0/2$, where $σ_0 (\geq 1)$ is a constant depending on the damping factor and natural frequency. The most general symmetric Gaussian states are obtai
K. A. Kirkpatrick
Withdrawn. Replaced by quant-ph/0308160 (cf accompanying txt file)
Evolution of economic entities under heterogeneous political/environmental conditions within a Bak-Sneppen-like dynamics
physics.soc-phMarcel Ausloos, Paulette Clippe, Andrzej Pekalski
A model for economic behavior, under heterogeneous spatial economic conditions is developed. The role of selection pressure in a Bak-Sneppen-like dynamics with entity diffusion on a lattice is studied by Monte-Carlo simulation taking into account business rule(s), like enterprise - enterprise short range location "interaction"(s), business plan(s) th
Li-Ching Hsieh, Chang-Heng Chang, Liaofu Luo, Fengmin Ji
Statistical analysis of distributions of occurrence frequencies of short words in 108 microbial complete genomes reveals the existence of a set of universal "root-sequence lengths" shared by all microbial genomes. These lengths and their universality give powerful clues to the way microbial genomes are grown. We show that the observed genomic propert
Borislav Pavlov
CMS experiment will use Resistive Plate Chambers (RPCs) as dedicated muon trigger detectors. The first 24 RPCs for the barrel muon system of the CMS experiment have been assembled and tested. A brief description of the cosmic muon telescope used for the tests is given. The preliminary results for the chamber performance are presented.
A. V. Avdeenkov, D. C. E. Bortolotti, J. L. Bohn
We explore the character of a novel set of ``field-linked'' states that were predicted in [A. V. Avdeenkov and J. L. Bohn, Phys. Rev. Lett. 90, 043006 (2003)]. These states exist at ultralow temperatures in the presence of an electrostatic field, and their properties are strongly dependent on the field's strength. We clarify the nature of these q
T. Frederico, J. H. O. Sales, B. V. Carlson, P. U. Sauer
The projection of the four-dimensional two-body Bethe-Salpeter equation at the light-front hypersurface is discussed. Elimination of the relative time is performed using a quasi-potential expansion, which is shown to be equivalent to an infinite set of coupled equations for the Green's functions of the different light-front Fock-states.
Ramesh Sreekantan
We define an analogue of the `Real' Deligne cohomology group at a prime of semi-stable or good reduction of a variety. We also define regulator maps to this group and formulate a conjecture about the image. This allows us to formulate a non-Archimedian version of Beilinson's Hodge-D-conjecture, S-integral and function field versions of Beilinson'
Zur Entartung gezuegelter Gruppenoperationen auf Kurven (Degeneration of restrained group actions on curves)
math.AGGunther Cornelissen, Fumiharu Kato
An action of a finite group on a smooth projective curve over an algebraically closed field of positive characteristic is called restrained, if all second ramification groups are trivial (e.g., every group action on an ordinary curve is restrained). When the ramification indices satisfy certain numerical criteria, we construct a degenerating equivariant quas
I. Scherbak
We consider the Gaudin model associated to a point z in C^n with pairwise distinct coordinates and to the subspace of singular vectors of a given weight in the tensor product of irreducible finite-dimensional sl_2-representations, [G]. The Bethe equations of this model provide the critical point system of a remarkable rational symmetric function. Any critica
I. Scherbak
Heine and Stieltjes in their studies of linear second-order differential equations with polynomial coefficients having a polynomial solution of a preassigned degree, discovered that the roots of such a solution are the coordinates of a critical point of a certain remarkable symmetric function, [He], [St]. Their result can be reformulated in terms of the Schu
S. M. Troshin, N. E. Tyurin
We note that recent results on the role of final state interactions in deep inelastic scattering make more complicated an extraction of a nucleon spin fraction carried by quarks from the experimental data obtained in deep inelastic scattering.
Indications for Criticality at Zero Curvature in a 4d Regge Model of Euclidean Quantum Gravity
hep-latWolfgang Beirl, Bernd A. Berg
We re-examine the approach to four-dimensional Euclidean quantum gravity based on the Regge calculus. A cut-off on the link lengths is introduced and consequently the gravitational coupling and the cosmological constant become independent parameters. We determine the zero curvature, $<R> =0$, line in the coupling constant plane by numerical simulations. When
M. Asakawa, T. Hatsuda
Analyzing correlation functions of charmonia at finite temperature ($T$) on $32^3\times(32-96)$ anisotropic lattices by the maximum entropy method (MEM), we find that $J/ψ$ and $η_c$ survive as distinct resonances in the plasma even up to $T \simeq 1.6 T_c$ and that they eventually dissociate between $1.6 T_c$ and $1.9 T_c$ ($T_c$ is the critical temperature
Topological Charged Black Holes in High Dimensional Spacetimes and Their Formation from Gravitational Collapse of a Type II Fluid
gr-qcYumei Wu, M. F. A. da Silva, N. O. Santos, Anzhong Wang
Topological charged black holes coupled with a cosmological constant in $R^{2}\times X^{D-2}$ spacetimes are studied, where $X^{D-2}$ is an Einstein space of the form ${}^{(D-2)}R_{AB} = k(D-3) h_{AB}$. The global structure for the four-dimensional spacetimes with $k = 0$ is investigated systematically. The most general solutions that represent a Type $II$ f
Alexander Haubold
We present a new visualization method to summarize and present periodic population movement between distinct locations, such as floors, buildings, cities, or the like. In the specific case of this paper, we have chosen to focus on student movement between college dormitories on the Columbia University campus. The visual information is presented to the inform
Alexander Haubold, John R. Kender
We present a new method for segmenting, and a new user interface for indexing and visualizing, the semantic content of extended instructional videos. Using various visual filters, key frames are first assigned a media type (board, class, computer, illustration, podium, and sheet). Key frames of media type board and sheet are then clustered based on contents
Magneto-optical properties of the quantum dot - impurity center systems synthesized in a transparent dielectric matrix
cond-mat.mtrl-sciV. D. Krevchik, A. B. Grunin, A. K. Aringazin, M. B. Semenov
Magneto-optical absorption by the quantum dot (QD) with impurity center (IC or D(-)-center) complexes synthesized in a transparent dielectric matrix, with consideration of the QD size dispersion, is theoretically studied. Within the framework of effective mass approach, the analytical expression for the light impurity magneto-optical absorption coefficient f
D. S. Petrov, C. Salomon, G. V. Shlyapnikov
We discuss the behavior of weakly bound bosonic dimers formed in a cold Fermi gas at a large positive scattering length $a$ for the interspecies interaction. We find the exact solution for the dimer-dimer elastic scattering and obtain a strong decrease of their collisional relaxation and decay with increasing $a$. The large ratio of the elastic to inelastic
G. Foffi, W. Gotze, F. Sciortino, P. Tartaglia
Molecular-dynamics simulations are presented for two correlation functions formed with the partial density fluctuations of binary hard-sphere mixtures in order to explore the effects of mixing on the evolution of glassy dynamics upon compressing the liquid into high-density states. Partial-density-fluctuation correlation functions for the two species are rep
Pankaj Mishra, Jokhan Ram, Yashwant Singh
We have used the density-functional theory to locate the freezing transitions and calculate the values of freezing parameters for a system of long elongated molecules which interact via the Gay-Berne pair potential. The pair correlation functions of isotropic phase which enter in the theory as input informations are found from the Percus-Yevick integral equa
Pilar Ruiz-Lapuente
The light curve of SN 1572 is described in the terms used nowadays to characterize SNeIa. By assembling the records of the observations done in 1572--74 and evaluating their uncertainties, it is possible to recover the light curve and the color evolution of this supernova. It is found that, within the SNe Ia family, the event should have been a SNIa with a n
Craig Tyler, Brent Janus, Diego Santos-Noble
The high redshifts of the most distant known quasars, and the best estimates of their black hole masses, require that supermassive black holes (SMBHs) must have formed very early in history. Several mechanisms for creating and growing these holes have been proposed. Here we present an evaluation of the timescales needed for various critical processes in orde
Barbara A. Whitney, Kenneth Wood, J. E. Bjorkman, Martin Cohen
We present model spectral energy distributions, colors, polarization, and images for an evolutionary sequence of a low-mass protostar from the early collapse stage (Class 0) to the remnant disk stage (Class III). We find a substantial overlap in colors and SEDs between protostars embedded in envelopes (Class 0-I) and T Tauri disks (Class II), especially at m
Peter Lundqvist, Seppo Mattila, Jesper Sollerman, E. Baron
Since April 2000, a program using the ESO/VLT/UVES to search for early circumstellar signatures from nearby supernovae has been conducted. Until now, two Type Ia supernovae have been observed, SNe 2000cx and 2001el. Here we report on preliminary results for SNe 2001el, and we discuss how the observations can be used together with detailed modeling to derive
Yeuk-Kwan E. Cheung, Laurent Freidel, Konstantin Savvidy
We provide a complete solution of closed strings propagating in Nappi-Witten space. Based on the analysis of geodesics we construct the coherent wavefunctions which approximate as closely as possible the classical trajectories. We then present a new free field realization of the current algebra using the gamma, beta ghost system. Finally we construct the qua
R. D. Matheus, F. S. Navarra, M. Nielsen, R. Rodrigues da Silva
We consider a $[ud]^2\bar{s}$ current in the QCD sum rule framework to study the mass of the recently observed pentaquark state $Θ^+(1540)$, obtaining good agreement with the experimental value. We also study the mass of the pentaquark $[ud]^2\bar{d}$. Our results are compatible with the interpretation of the $[ud]^2\bar{d}$ state as being the Roper resonanc
Vittorio Giovannetti, Seth Lloyd, Lorenzo Maccone
We analyze the role of nonlinear Hamiltonians in bosonic channels. We show that the information capacity as a function of the channel energy is increased with respect to the corresponding linear case, although only when the energy used for driving the nonlinearity is not considered as part of the energetic cost and when dispersive effects are negligible.
W. T. Ford
I describe the experimental determination of the CKM angle beta from measurements of the decay time separation delta t between B0 mesons produced as B Bbar pairs in e+e- annihilation. The current results from leading and non-leading decay modes are presented and compared.
Bogdan Nica
We describe a correspondence between spaces with walls and CAT(0) cube complexes.
Deog Ki Hong, Stephen D. H. Hsu
We show that higher dimensional models (brane worlds) in which the scale of quantum gravity $M_*$ is much smaller than the apparent scale $M_P \sim 10^{19}$ GeV are in conflict with bounds arising from holography and black hole entropy. The thermodynamic entropy of astrophysical black holes and sub-horizon volumes during big bang nucleosynthesis exceed the r
Enlarging the Parameter Space of Heterotic M-Theory Flux Compactifications to Phenomenological Viability
hep-thGottfried Curio, Axel Krause
Heterotic M-Theory is a promising candidate for that corner of M-theory which makes contact with the real world. However, while the theory requires one of its expansion parameters, $ε$, to be perturbatively small, a successful phenomenology requires $ε= {\cal O}(1)$. We show that the constraint to have small $ε$ is actually unnecessary: instead of the origin
STAR Collaboration, J. Adams
We present the first large-acceptance measurement of event-wise mean transverse momentum mean p_t fluctuations for Au-Au collisions at nucleon-nucleon center-of-momentum collision energy sqrt{s_{NN}} = 130 GeV. The observed non-statistical mean p_t fluctuations substantially exceed in magnitude fluctuations expected from the finite number of particles produc
Takuya Tsukioka, Yoshiyuki Watabiki
We investigate the quantization of the bosonic string model which has a local U(1)_V * U(1)_A gauge invariance as well as the general coordinate and Weyl invariance on the world-sheet. The model is quantized by Lagrangian and Hamiltonian BRST formulations {á} la Batalin, Fradkin and Vilkovisky and noncovariant light-cone gauge formulation. Upon the quantizat
R. Shyam, H. Lenske, U. Mosel
The exclusive $K^+$ meson production in a proton-nucleus collision, leading to two body final states, is investigated in a fully covariant two-nucleon model based on the effective Lagrangian picture. The explicit kaon production vertex is described via creation, propagation and decay into relevant channel of $N^*$(1650), $N^*$(1710) and $N^*$(1720) intermedi
L. Acedo, A. Santos
We consider a fluid of $d$-dimensional spherical particles interacting via a pair potential $ϕ(r)$ which takes a finite value $ε$ if the two spheres are overlapped ($r<σ$) and 0 otherwise. This penetrable-sphere model has been proposed to describe the effective interaction of micelles in a solvent. We derive the structural and thermodynamic functions in the
Andrey V. Kravtsov, Andreas A. Berlind, Risa H. Wechsler, Anatoly A. Klypin
We analyze the halo occupation distribution (HOD), the probability for a halo of mass M to host a number of subhalos N, and two-point correlation function of galaxy-size dark matter halos using high-resolution dissipationless simulations of the concordance flat LCDM model. The halo samples include both the host halos and the subhalos, distinct gravitationall
Topological constraints on spiral wave dynamics in spherical geometries with inhomogeneous excitability
nlin.PSJörn Davidsen, Leon Glass, Raymond Kapral
We analyze the way topological constraints and inhomogeneity in the excitability influence the dynamics of spiral waves on spheres and punctured spheres of excitable media. We generalize the definition of an index such that it characterizes not only each spiral but also each hole in punctured, oriented, compact, two-dimensional differentiable manifolds and s
K. Thirulogasanthar, G. Honnouvo, A. Krzyzak
A class of vector coherent states is derived with multiple of matrices as vectors in a Hilbert space, where the Hilbert space is taken to be the tensor product of several other Hilbert spaces. As examples vector coherent states with multiple of quaternions and octonions are given. The resulting generalized oscillator algebra is briefly discussed. Further, ve
Hot Spots and Pseudogaps for Hole- and Electron-Doped High-Temperature Superconductors
cond-mat.str-elDavid Senechal, A. -M. S. Tremblay
Using cluster perturbation theory, it is shown that the spectral weight and pseudogap observed at the Fermi energy in recent Angle Resolved Photoemission Spectroscopy (ARPES) of both electron and hole-doped high-temperature superconductors find their natural explanation within the t-t'-t''-U Hubbard model in two dimensions. The value of the inter
C. Done, G. Wardzinski, M. Gierlinski
We compare the evolution of spectral shape with luminosity in GRS 1915+105 with that of 'normal' black holes. The pathological time variability of GRS 1915+105 does not indicate that it belongs in a different class to all the other objects. At comparable fraction of Eddington luminosity its spectra and (more importantly) time variability behaviour ar
Luca Donetti, Claudio Destri
The properties of scale-free random trees are investigated using both preconditioning on non-extinction and fixed size averages, in order to study the thermodynamic limit. The scaling form of volume probability is found, the connectivity dimensions are determined and compared with other exponents which describe the growth. The (local) spectral dimension is a