arXiv papers from August 2003

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 halo.

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

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

Andrei Khrennikov, Yaroslav Volovich

We analyze statistical consequences of a conjecture that there exists a fundamental (indivisible) quant of time. We study particle dynamics with discrete time. We show that a quantum-like interference pattern could appear as a statistical effect for deterministic particles, i.e. particles that have trajectories and obey deterministic dynamical equations, if

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

S. 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

Timothy Prescott, Francis Edward Su

Our paper gives bounds for the rate of convergence for a class of random walks on the d-dimensional torus generated by a set of n vectors in R^d/Z^d. We give bounds on the discrepancy distance from Haar measure; our lower bound holds for all such walks, and if the generators arise from the rows of a "badly approximable" matrix, then there is a corresponding

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.

Allison Woodruff, Paul M. Aoki

This paper presents an exploratory study of college-age students using two-way, push-to-talk cellular radios. We describe the observed and reported use of cellular radio by the participants, the activities and purposes for which they adopted it, and their responses. We then examine these empirical results using mediated communication theory. Cellular radios

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

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.

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

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

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

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

A. 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

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

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

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.

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.

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

Yu. 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.

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

Stanislav 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

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

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

Yu. 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

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

Yu. 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

Monica 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

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

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

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

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 $\sigma$-model limits. Combined with the ground state TBA equations the exact mass gap is computed in the O(3) and O(4) nonlinear $\sigma$-model and the results are compared to 3-loop perturbation theory and Monte Carlo data.

Jian Qi Shen

Three related topics on the quantum-vacuum geometric phases in a noncoplanarly curved optical fiber is presented: (i) a brief review: the investigation of vacuum effect and its experimental realization; (ii) the sequence of ideas of geometric phases in the fiber; (iii) three derivations of effective Hamiltonian that describes the wave propagation of photon f

Jian 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

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,

A. 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

Hendrik Heinz, Wolfgang Paul, Kurt Binder

Local pressures are important in the calculation of interface tensions and in analyzing micromechanical behavior. The calculation of local pressures in computer simulations has been limited to systems with pairwise interactions between the particles, which is not sufficient for chemically detailed systems with many-body potentials such as angles and torsions

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

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.

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.

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

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 increasingly

Boris 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

Rafael A. Vera

The Einstein&#39;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

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

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

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 Gon\c{c}alves [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 form ei

Yumei 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

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's global con

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.

Wolfgang 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. Tzortzis, E. Svoukis, H. Tsertos

A survey was carried out to determine activity concentration levels and associated dose rates from the naturally occurring radionuclides Th-232, U-238, and K-40, in the various geological formations appearing throughout the geographically accessible area of Cyprus, by means of high-resolution gamma-ray spectrometry. A total number of 115 representative soil

A. A. Arkhipov

We suggest that Kaluza-Klein idea may provide the global solution of the spectral problem in hadronic spectroscopy.

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

Michalis Tzortzis, Haralabos Tsertos

A comprehensive study was conducted to determine thorium, uranium and potassium elemental concentrations in surface soils throughout the accessible area of Cyprus using high-resolution gamma-ray spectrometry. A total of 115 soil samples was collected from all over the bedrock surface of the island based on the different lithological units of the study area.

Gunther 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

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

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

Marcel 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) through sp

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 properties are

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 $J/\psi$ and $\eta_c$ 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 tempe

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.

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.

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;

Sang 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 $\Delta q \Delta p = \hbar \sigma_0/2$, where $\sigma_0 (\geq 1)$ is a constant depending on the damping factor and natural frequency. The most general symmetric Gau

M. Hsieh, J. Kempe, S. Myrgren, K. B. Whaley

A single physical interaction might not be universal for quantum computation in general. It has been shown, however, that in some cases it can generate universal quantum computation over a subspace. For example, by encoding logical qubits into arrays of multiple physical qubits, a single isotropic or anisotropic exchange interaction can generate a universal

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

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 quasi-bound s

V. 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

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

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

Daniele C. E. Bortolotti, John L. Bohn

We consider the problem of an atomic beam propagating quantum mechanically through an atom beam splitter. Casting the problem in an adiabatic representation (in the spirit of the Born-Oppenheimer approximation in molecular physics) sheds light on explicit effects due to non-adiabatic passage of the atoms through the splitter region. We are thus able to probe

Laird M. Close, Francois Wildi, Michael Lloyd-Hart, Guido Brusa

We present the first scientific images obtained with a deformable secondary mirror adaptive optics system. We utilized the 6.5m MMT AO system to produce high-resolution (FWHM=0.07'') near infrared (1.6 um) images of the young (~1 Myr) Orion Trapezium theta 1 Ori cluster members. A combination of high spatial resolution and high signal to noise allowed the po

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 $\Theta^+(1540)$, 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 res

C. J. McKinstrie, P. J. Winzer

This report contains a tutorial introduction to the method of importance sampling. The use of this method is illustrated for simulations of the noise-induced energy jitter of return-to-zero pulses in optical communication systems.

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.

Felix Lev

The modern quantum theory is based on the assumption that quantum states are represented by elements of a complex Hilbert space. It is expected that in future quantum theory the number field will be not postulated but derived from more general principles. We consider the choice of the number field in quantum theory based on a Galois field (GFQT) discussed in

Bogdan Nica

We describe a correspondence between spaces with walls and CAT(0) cube complexes.

Peter W. Milonni, Robert W. Boyd

Motivated by recent discussions concerning the manner in which damping appears in the electric polarizability, we show that (a) there is a dependence of the nonresonant contribution on the damping and that (b) the damping enters according to the "opposite sign prescription." We also discuss the related question of how the damping rates in the polarizability

Andrew Gould, Julio Chaname

We present a catalog of 424 common proper motion companions to Hipparcos stars with good (>3 sigma) parallaxes, thereby effectively providing new parallaxes for these companions. Compared to stars in the Hipparcos catalog, these stars are substantially dimmer. The catalog includes 20 WDs and an additional 29 stars with M_V>14, the great majority of the latte

D. J. Dean, M. Hjorth-Jensen

Using many-body perturbation theory and coupled-cluster theory, we calculate the ground-state energy of He-4 and O-16. We perform these calculations using a no-core G-matrix interaction derived from a realistic nucleon-nucleon potential. Our calculations employ up to two-particle-two-hole coupled-cluster amplitudes.

A. T. Boothroyd, P. G. Freeman, D. Prabhakaran, M. Enderle

We have studied magnetic correlations in several compositions of stripe-ordered La2-xSrxNiO4. In this paper we show how polarized-neutron scattering has helped uncover important features of the magnetic ordering and spin dynamics. In particular, polarization analysis has enabled us (1) to characterize a spin reorientation transition, (2) to identify anisotro

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

A. T. Boothroyd, P. G. Freeman, D. Prabhakaran, H. Woo

We report neutron scattering measurements of the spectrum of magnetic excitations in the stripe-ordered phase of La2-xSrxNiO4 (x=0.275 and 1/3). The propagating spin excitations follow a similar dispersion relation for the two compositions, but the line widths are broader for x=0.275 than for x=1/3.

A. A. Arkhipov

In this note we propose to search new strange $a_2^s(1520)$-meson which is a strange partner of the $a_2(1311)$-meson observed in a three-pion system.

Rainer Kaltenbaek, Markus Aspelmeyer, Thomas Jennewein, Caslav Brukner

Quantum physics experiments in space using entangled photons and satellites are within reach of current technology. We propose a series of fundamental quantum physics experiments that make advantageous use of the space infrastructure with specific emphasis on the satellite-based distribution of entangled photon pairs. The experiments are feasible already tod

Gottfried 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, $\epsilon$, to be perturbatively small, a successful phenomenology requires $\epsilon = {\cal O}(1)$. We show that the constraint to have small $\epsilon$ is actually unnecessary:

Vishvajit V. S. Gautam

In this paper we propose a naive construction of 2-dimensional extended topological quantum field theories (TQFTs), which can be further generalized to the higher-dimension extended TQFTs.