December 2003 arXiv papers — page 2

Yusuke Nishida

Quantum chromodynamics (QCD) at finite temperature (T), baryon chemical potential (\muB) and isospin chemical potential (\muI) is studied in the strong coupling limit on a lattice with staggered fermions. With the use of large dimensional expansion and the mean field approximation, we derive an effective action written in terms of the chiral condensate and p

Chaiho Rim, Yunseok Seo, Jae Hyung Yee

The perturbative framework of the space-time non-commutative real scalar field theory is formulated, based on the unitary S-matrix. Unitarity of the S-matrix is explicitly checked order by order using the Heisenberg picture of Lagrangian formalism of the second quantized operators, with the emphasis of the so-called minimal realization of the time-ordering s

T. Abe, R. Seki, A. N. Kocharian

Thermal properties of single species nucleon matter are investigated assuming a simple form of the nucleon-nucleon interaction. The nucleons are placed on a cubic lattice, hopping from site to site and interacting through a spin-dependent force, as in the extended, attractive Hubbard model. A mean field calculation in the Hartree-Fock Bogoliubov approximatio

Thomas Geisser, Lars Hesselholt

We determine the structure modulo p of the de Rham-Witt complex of a smooth scheme X over a discrete valuation ring of mixed characteristic with log-poles along the special fiber Y and show that the sub-sheaf fixed by the Frobenius is isomorphic to the sheaf of p-adic vanishing cycles. We use this together with results of the second author and Madsen to eval

H. Itoyama, H. Kanno

N=2 supersymmetric U(N) Yang-Mills theory softly broken to N=1 by the superpotential of the adjoint scalar fields is discussed from the viewpoint of the Whitham deformation theory for prepotential. With proper identification of the superpotential we derive the matrix model curve from the condition that the mixed second derivatives of the Whitham prepotential

Milan Mosonyi, Denes Petz

Let H and K be Hilbert spaces and T be a coarse-graining from B(H) to B(K). Assume that density matrices D_1 and D_2 acting on H are given. In the paper the consequences of the existence of a coarse-graining S from B(K) to B(H) satisfying ST(D_1)=D_1 and ST(D_2)=D_2 are given. (This condition means the sufficiency of T for D_1 and D_2.) Sufficiency implies a

Pawel Wegrzyn

We discuss the quantized field inside a general one-dimensional cavity system. We recognize the $SL(2,R)$ symmetry being the remainder of the conformal group. The explanation of the lack of the resonance production for the fundamental frequency is given and the asymptotic behavior of the cavity system is properly described.

Pawel Wegrzyn

We present the study of parametric resonance in a one-dimensional cavity based on the analysis of classical optical paths. The recursive formulas for field energy are given. We separate the mechanism of particle production and the resonance amplification of radiation. The production of photons is a purely quantum effect described in terms of quantum anomalie

Yaoyun Shi

We propose an approach for quantifying a quantum circuit's quantumness as a means to understand the nature of quantum algorithmic speedups. Since quantum gates that do not preserve the computational basis are necessary for achieving quantum speedups, it appears natural to define the quantumness of a quantum circuit using the number of such gates. Intuiti

Stephen Fenner, Frederic Green, Steven Homer, Yong Zhang

We show that if a language is recognized within certain error bounds by constant-depth quantum circuits over a finite family of gates, then it is computable in (classical) polynomial time. In particular, our results imply EQNC^0 is contained in P, where EQNC^0 is the constant-depth analog of the class EQP. On the other hand, we adapt and extend ideas of Terh

E. Simon Myrgren, K. Birgitta Whaley

We present Monte Carlo wavefunction simulations for quantum computations employing an exchange-coupled array of quantum dots. Employing a combination of experimentally and theoretically available parameters, we find that gate fidelities greater than 98 % may be obtained with current experimental and technological capabilities. Application to an encoded 3 qub

Nitin Gupta, Anders Irbäck

Using a simple hydrophobic/polar protein model, we perform a Monte Carlo study of the thermodynamics and kinetics of binding to a target structure for two closely related sequences, one of which has a unique folded state while the other is unstructured. We obtain significant differences in their binding behavior. The stable sequence has rigid docking as its

Giorgio Favrin, Anders Irbäck, Stefan Wallin

ZSPA-1 is an engineered protein that binds to its parent, the three-helix-bundle Z domain of staphylococcal protein A. Uncomplexed ZSPA-1 shows a reduced helix content and a melting behavior that is less cooperative, compared with the wild-type Z domain. Here we show that the difference in folding behavior between these two sequences can be partly understood

Giorgio Favrin, Anders Irbäck, Björn Samuelsson, Stefan Wallin

We present a Monte Carlo study of a model protein with 54 amino acids that folds directly to its native three-helix-bundle state without forming any well-defined intermediate state. The free-energy barrier separating the native and unfolded states of this protein is found to be weak, even at the folding temperature. Nevertheless, we find that melting curves

Anders Irbäck, Björn Samuelsson, Fredrik Sjunnesson, Stefan Wallin

An atomic protein model with a minimalistic potential is developed and then tested on an alpha-helix and a beta-hairpin, using exactly the same parameters for both peptides. We find that melting curves for these sequences to a good approximation can be described by a simple two-state model, with parameters that are in reasonable quantitative agreement with e

Ping Xie, Shuo-Xing Dou, Peng-Ye Wang

Myosin V and myosin VI are two classes of two-headed molecular motors of the myosin superfamily that move processively along helical actin filaments in opposite directions. Here we present a hand-over-hand model for their processive movements. In the model, the moving direction of a dimeric molecular motor is automatically determined by the relative orientat

Ping Xie, Shuo-Xing Dou, Peng-Ye Wang

Kinesin motors have been studied extensively both experimentally and theoretically. However, the microscopic mechanism of the processive movement of kinesin is still an open question. In this paper, we propose a hand-over-hand model for the processivity of kinesin, which is based on chemical, mechanical, and electrical couplings. In the model the processive

Anders Irbäck, Fredrik Sjunnesson

We study the folding thermodynamics of a beta-hairpin and two three-stranded beta-sheet peptides using a simplified sequence-based all-atom model, in which folding is driven mainly by backbone hydrogen bonding and effective hydrophobic attraction. The native populations obtained for these three sequences are in good agreement with experimental data. We also

V. Hnizdo

The expression for the Coulomb-gauge vector potential in terms of the `instantaneous' magnetic field derived by Stewart [2003 Eur. J. Phys. 24, 519] by employing Jefimenko's equation for the magnetic field and Jackson's formula for the Coulomb-gauge vector potential can be proven much more simply.

M. S. Hussein, B. V. Carlson, T. Frederico, T. Tarutina

The purpose of this work is to show that within a three-body description, the complete fusion process and the target excitation by the projectile can be taken into account by introducing a three-body optical potential in the formalism. We give a schematic description of such a potential and points to ways of testing the validity of the CDCC.

Silvius Klein

In this paper we consider the discrete one-dimensional Schroedinger operator with quasi-periodic potential v_n = λv (x + n ω). We assume that the frequency ωsatisfies a strong Diophantine condition and that the function v belongs to a Gevrey class, and it satisfies a transversality condition. Under these assumptions we prove - in the perturbative regime - th

David B. Chandler, Peter Sin, Qing Xiang

We determine the Smith normal forms of the incidence matrices of points and projective (r-1)-dimensional subspaces of PG(n,q) and of the incidence matrices of points and r-dimensional affine subspaces of AG(n,q) for all n, r, and arbitrary prime power q.

Patricia Hersh, Volkmar Welker

The purpose of this paper is twofold. 1. We give combinatorial bounds on the ranks of the groups $\Tor^{R}_\bullet(k,k)_\bullet$ in the case where $R = k[Λ]$ is an affine semi-group ring, and in the process provide combinatorial proofs for bounds by Eisenbud, Reeves and Totaro on which Tor groups vanish. In addition, we show that if the bounds hold for a fie

D. Alpay, M. Shapiro, D. Volok

We introduce the notion of rationality for hyperholomorphic functions (functions in the kernel of the Cauchy-Fueter operator). Following the case of one complex variable, we give three equivalent definitions: the first in terms of Cauchy-Kovalevskaya quotients of polynomials, the second in terms of realizations and the third in terms of backward-shift invari

V. P. Spiridonov

The notion of integral Bailey pairs is introduced. Using the single variable elliptic beta integral, we construct an infinite binary tree of identities for elliptic hypergeometric integrals. Two particular sequences of identities are explicitly described.

Masayoshi Kaneda, Vern I. Paulsen

We use the injective envelope to study quasimultipliers of operator spaces. We prove that all representable operator algebra products that an operator space can be endowed with are induced by quasimultipliers. We obtain generalizations of the Banach-Stone theorem.

Hokuto Uehara

We study Calabi--Yau 3-folds with infinitely many divisorial contractions. We also suggest a method to describe Calabi--Yau 3-folds with the infinite automorphism group.

B. L. Mazov

Title: Global stabilization of control nonlinear system "inverted pendulum on a cart" using method of two Lyapunov functions Authors: B. L. Mazov (Nizhny Novgorod Technical University) Comments: 10 pages Subj-class: Dynamical Systems MSC-class: 34D23 (Primary); 93H10 (Secondary) In this work a mathematical apparatus for method of several global Lyapu

Ralph M. Kaufmann

Previously, we introduced a duality transformation for Euler $G$--Frobenius algebras. Using this transformation, we prove that the simple $A,D,E$ singularities and Pham singularities of coprime powers are mirror self--dual where the mirror duality is implemented by orbifolding with respect to the symmetry group generated by the grading operator and dualizing

Thomas C. Hales

These notes give a statement of the "fundamental lemma," which is a conjectural identity between p-adic integrals that arises as part of the Langlands program.

C. Ivanescu

A classification is given of certain separable nuclear C*-algebras not necessarily of real rank zero, namely the class of simple C*-algebras which are inductive limits of continuous-trace C*-algebras whose building blocks have their spectrum homeomorphic to the interval [0,1] or to a finite disjoint union of closed intervals. In particular, a classification

Yuri A. Turygin

In this paper we prove the equivalence of the questions of B.A. Pasynkov and V.V. Uspenskij. We also get some partial results answering these questions in affirmative. As a corollary to these results we get an extention of the Hurewicz formula to the extensional dimension.

Gabriel Katz

Let $M^3$ be an oriented 3-manifold. We investigate when one of the fibers or a combination of fiber components, $F_{best}$, of a \emph{harmonic} map $f: M^3 \to S^1$ with Morse-type singularities delivers the Thurston norm $χ_-([F_{best}])$ of its homology class $[F_{best}] \in H_2(M^3; \Z)$. In particular, for a map $f$ with connected fibers and any well-p

M. Lynker, R. Schimmrigk, S. Stewart

We propose a conceptual framework that leads to an abstract characterization for the exact solvability of Calabi-Yau varieties in terms of abelian varieties with complex multiplication. The abelian manifolds are derived from the cohomology of the Calabi-Yau manifold, and the conformal field theoretic quantities of the underlying string emerge from the number

H. Dehnen, V. D. Ivashchuk, V. N. Melnikov

Multidimensional cosmological-type model with n Einstein factor spaces in the theory with l scalar fields and multiple exponential potential is considered. The dynamics of the model near the singularity is reduced to a billiard on the (N-1)-dimensional Lobachevsky space H^{N-1}, N = n+l. It is shown that for n > 1 the oscillating behaviour near the singulari

Helmuth Huffel, Gerald Kelnhofer

We perform the stochastic quantization of scalar QED based on a generalization of the stochastic gauge fixing scheme and its geometric interpretation. It is shown that the stochastic quantization scheme exactly agrees with the usual path integral formulation.

Giovanni Amelino-Camelia, Luisa Doplicher

Some recent studies of the properties of D-particles suggest that in string theory a rather conventional description of spacetime might be available up to scales that are significantly smaller than the Planck length. We test this expectation by analyzing the localization of a space-time event marked by the collision of two D-particles. We find that a spatial

A. E. Shalyt-Margolin

In this paper a new small parameter associated with the density matrix deformation (density pro-matrix)studied in previous works of the author is introduced into the Generalized Quantum Mechanics (GQM), i.e. quantum mechanics involving description of the Early Universe. It is noted that this parameter has its counterpart in the generalized statistical mechan

Satoshi Iso, Hiroshi Umetsu

We construct a supermatrix model whose classical background gives two-dimensional noncommutative supersphere. Quantum fluctuations around it give the supersymmetric gauge theories on the fuzzy supersphere constructed by Klimcik. This model has a parameter $β$ which can tune masses of the particles in the model and interpolate various supersymmetric gauge the

M. W. Kalinowski

We consider in the paper some consequences of the nonsymmetric Kaluza-Klein (Jordan-Thiry) theory with spontaneous symmetry breaking connecting to the existence of the warp factor and communnication in extra-dimensions. We consider a toy model of a time machine.

Chuan-Tsung Chan, Jen-Chi Lee

We show that U(\infty) symmetry transformations of the noncommutative field theory in the Moyal space are generated by a combination of two W_{1+\infty} algebras in the Landau problem. Geometrical meaning of this infinite symmetry is illustrated by examining the transformations of an invariant subgroup on the noncommutative solitons, which generate deformati

M. V. Chistyakov, N. V. Mikheev

The two-photon two-neutrino interaction induced by magnetic field is investigated. In particular the processes $γγ\to ν\bar ν$ and $γ\to γν\bar ν$ are studied in the presence of strong magnetic field. An effective Lagrangian and partial amplitudes of the processes are presented. Neutrino emissivities due to the reactions $γγ\to ν\bar ν$ and $γ\to γν\bar ν$ a

A. N. Ioannisian, N. A. Kazarian

We have studied mixing and masses of three left handed Majorana neutrinos in the model, which assumes exactly degenerate neutrino masses at some "neutrino unification" scale. Such a simple theoretical ansatz naturally leads to quasidegenerate neutrinos. The neutrino mass splittings induced by renormalization effects. In the model we found that the pa

D. J. H. Chung, L. L. Everett, G. L. Kane, S. F. King

After an introduction recalling the theoretical motivation for low energy (100 GeV to TeV scale) supersymmetry, this review describes the theory and experimental implications of the soft supersymmetry-breaking Lagrangian of the general minimal supersymmetric standard model (MSSM). Extensions to include neutrino masses and nonminimal theories are also discuss

Francesco Sannino

I briefly discuss effective Lagrangians for strong interactions while concentrating on two specific lagrangians for QCD at large matter density. I then introduce spectral duality in QCD a la Montonen and Olive. The latter is already present in QCD in the hadronic phase. However it becomes transparent at large chemical potential. Finally I show the relevance

I. F. Ginzburg, I. P. Ivanov

We obtain tree-level unitarity constraints for the Two Higgs Doublet Model (2HDM) with explicit CP-violation. We limit ourselves to the case with soft violation of the discrete Z_2 symmetry of theory. The key role is played by the rephasing invariance of the 2HDM lagrangian. Our simple approach for derivation of these constraints can be easily transferred to

Pedro Bicudo

The mass gap equation for spontaneous chiral symmetry breaking is studied directly in Minkowsky space. In hadronic physics, spontaneous chiral symmetry breaking is crucial to generate a constituent mass for the quarks, and to produce the Partially Conserved Axial Current theorems, including a small mass for the pion. Here a class of finite kernels is used, e

F. Jegerlehner

I present a summary of recent developments as they have been discussed in the many interesting contributions to the workshop SIGHAD03 at Pisa.

A. V. Nesterenko

A recently developed model for the QCD analytic invariant charge is compared with quenched lattice simulation data on the static quark-antiquark potential. By employing this strong running coupling one is able to obtain the confining quark-antiquark potential in the framework of the one-gluon exchange model. To achieve this objective a technique for evaluati

M. Lorente

Following recent assumptions to unify quantum mechanics and general relativity, the structure of spacetime is suppose to be a consequence of the relations among some fundamental objects, and its concept can be formulated without the reference to the intuition. As physical consequences the continuous laws should be translated in to difference equations and th

G. Eigen, G. P. Dubois-Felsmann, D. G. Hitlin, F. C. Porter

We report upon the present status of global fits to Cabibbo-Kobayashi-Maskawa matrix.

Giovanni Amelino-Camelia, Jerzy Kowalski-Glikman, Gianluca Mandanici, Andrea Procaccini

Investigations of the possibility that some novel ``quantum" properties of spacetime might induce a modification dispersion relation focused at first on scenarios with Planck-scale violations of Lorentz symmetry. More recently several studies have considered the possibility of a ``doubly special relativity", in which the modification of the dispersio

Sergio M. C. V. Goncalves

We consider spherically symmetric spacetimes with matter whose timelike flow is assumed to be shear-free. A number of results on the formation and visibility of spacetime singularities is proven, with the main one being that shear-free collapse cannot admit locally naked singularities (which implies absence of globally naked singularities). We conjecture tha

Sergio M. C. V. Goncalves

We consider four-dimensional spacetimes $(M,{\mathbf g})$ which obey the Einstein equations ${\mathbf G}={\mathbf T}$, and admit a global spacelike $G_{1}={\mathbb R}$ isometry group. By means of dimensional reduction and local analyis on the reduced (2+1) spacetime, we obtain a sufficient condition on ${\mathbf T}$ which guarantees that $(M,{\mathbf g})$ ca

Sergio M. C. V. Goncalves

We show that (3+1) vacuum spacetimes admitting a global, spacelike, one-parameter Lie group of isometries of translational type cannot contain apparent horizons. The only assumption made is that of the existence of a global spacelike Killing vector field with infinite open orbits; the four-dimensional vacuum spacetime metric is otherwise arbitrary. This resu

S. L. Cherkas

We have shown that DeWitt constraint H=0 on the physical states of the Universe does not prevent Heisenberg operators and its mean values to evolve with time. Mean value from observable, which is singular in classical theory, is also singular in a quantum case.

M. Lorente

We present current theories about the structure of space and time, where the building blocks are some fundamental entities (yes-no experiment, quantum processes, spin net-work, preparticles) that do not presuppose the existence of space and time. The relations among these objects are the base for a pregeometry of discrete character, the continuous limit of w

Sean A. Hayward

A recent refinement of Penrose's conformal framework for asymptotically flat space-times is summarized. The key idea concerns advanced and retarded conformal factors, which allow a rigid description of infinity as a locally metric light cone. In the new framework, the Bondi-Sachs energy-flux integrals of ingoing and outgoing gravitational radiation decay

Sergio M. C. V. Goncalves

We show that four-dimensional Lorentzian metrics admitting a global spacelike Lie group of isometries, $G_{1}={\mathbb R}$, which obey the Einstein equations for vacuum and certain types of matter, cannot contain apparent horizons. The assumed global isometry allows for the dimensional reduction of the (3+1) system to a (2+1) picture, wherein the four-dimens

L. S. Schulman, B. Gaveau

A stochastic dynamics framework for the study of complex systems is presented.

A. Ya. Maltsev, S. P. Novikov

In this article we give the basic concept of the "Topological Numbers" in theory of quasiperiodic functions. The main attention is paid to apperance of such values in transport phenomena including Galvanomagnetic phenomena in normal metals (Chapter 1) and the modulations of 2D electron gas (Chapter 2). We give just the main introduction to both of th

C. Malyshev

A continual model of non-singular screw dislocation lying along a straight infinitely long circular cylinder is investigated in the framework of translational gauge approach with the Hilbert--Einstein gauge Lagrangian. The stress--strain constitutive law implies the elastic energy of isotropic continuum which includes the terms of second and third orders in

A. Ya. Maltsev, S. P. Novikov

We represent here the full description of all asymptotic regimes of conductivity behavior in the so-called "Geometric Strong Magnetic Field limit" in the 3D single crystal normal metals with topologically complicated Fermi surfaces. In particular, new observable integer-valued characteristics of conductivity of the topological origin were introduced

A. A Gippius, E. N. Morozova, A. S. Moskvin, A. V. Zalessky

We report on {6,7}Li nuclear magnetic resonance measurements of the spin-chain compound LiCu2O2 in the paramagnetic and magnetically ordered states. Below T about 24 K the NMR lineshape presents a clear signature of incommensurate (IC) static modulation of the local magnetic field consistent with an IC spiral modulation of the magnetic moments. {7}Li NMR rev

Sameer Sapra, D. D. Sarma

In order to provide a quantitatively accurate description of the band gap variation with sizes in various II-VI semiconductor nanocrystals, we make use of the recently reported tight-binding parametrization of the corresponding bulk systems. Using the same tight-binding scheme and parameters, we calculate the electronic structure of II-VI nanocrystals in rea

S. Peng, F. Ding, B. Urbanc, S. V. Buldyrev

We study the aggregation of peptides using the discrete molecular dynamics simulations. At temperatures above the alpha-helix melting temperature of a single peptide, the model peptides aggregate into a multi-layer parallel beta-sheet structure. This structure has an inter-strand distance of 0.48 nm and an inter-sheet distance of 1.0 nm, which agree with exp

Jae-Hyeon Eom, Sung-Sik Lee, Ki-Seok Kim, Sung-Ho Suck Salk

The U(1) holon-pair boson theory of Lee and Salk(Phys. Rev. B 64, 052501 (2001)) is applied to investigate the quantum scaling behavior of optical conductivity in the two dimensional systems of strongly correlated electrons. We examine the role of both the gauge field fluctuations and spin pair excitations on the w/T scaling behavior of the optical conductiv

Jens Eggers, Robert Evans

We comment on a recent theory of dynamic wetting, that is based directly upon a model for interface formation, introduced by Shikhmurzaev. We argue that the treatment of surface tension and its relaxation, inherent in the original model, is physically flawed.

A. Pashkin, V. Zelezny, M. Savinov, J. Petzelt

Chen Ang, Bhalla and Cross [Phys. Rev. B 64, 184104 (2001)] have studied the low-frequency (20 Hz -- 100 kHz) dielectric dispersion of the KTaO3 crystal under a dc electric field. Performing fits of the electric field dependence they came to conclusion that an appreciable contribution to the dielectric permittivity originates from polar clusters. In this Com

I. S. Burmistrov

We study the conductivity of two-dimensional interacting electrons on the half-filled $N$th Landau level with $N \gg 1$ in the presence of the quenched disorder. The existence of the unidirectional charge-density wave state at temperature $T<T_c$, where $T_c$ is the transition temperature, leads to the anisotropic conductivity tensor. We find that the leadin

G. M. Shmelev, E. M. Epshtein, A. S. Matveev

A fluctuation theory is presented for the nonequilibrium second order phase transition in a quasi-two-dimensional electron gas. A transverse (with respect to the current through the sample) spontaneous electric field as an order parameter and a driving longitudinal field as a control parameter are used. In addition to the earlier results, the intrawell dynam

Y. Alhassid, T. Rupp

We derive a universal Hamiltonian for a quantum dot in the presence of spin-orbit interaction in the symmetry limits of a strong spin-dependent Aharonov-Bohm-like term. We also derive a closed expression for the conductance through such a dot, and use it to study the effects of spin-orbit on the conductance peak statistics in the presence of an exchange inte

D. J. Huang, W. B. Wu, G. Y. Guo, H-J Lin

We found that the conventional model of orbital ordering of 3x^2-r^2/3y^2-r^2 type in the eg states of La_0.5Sr_1.5MnO_4 is incompatible with measurements of linear dichroism in the Mn 2p-edge x-ray absorption, whereas these eg states exhibit predominantly cross-type orbital ordering of x^2-z^2/y^2-z^2. LDA+U band-structure calculations reveal that such a cr

A. Helmstetter, S. Hergarten, D. Sornette

Following Hergarten and Neugebauer [2002] who discovered aftershock and foreshock sequences in the Olami-Feder-Christensen (OFC) discrete block-spring earthquake model, we investigate to what degree the simple toppling mechanism of this model is sufficient to account for the properties of earthquake clustering in time and space. Our main finding is that synt

R. Kawai, X. Sailer, L. Schimansky-Geier, C. Van den Broeck

Bistability generated via a pure noise-induced phase transition is reexamined from the view of bifurcations in macroscopic cumulant dynamics. It allows an analytical study of the phase diagram in more general cases than previous methods. In addition using this approach we investigate patially-extended systems with two degrees of freedom per site. For this sy

Tetsuo Deguchi

Some features of integrable lattice models are reviewed for the case of the six-vertex model. By the Bethe ansatz method we derive the free energy of the six-vertex model. Then, from the expression of the free energy we show analytically the critical singularity near the phase transition in the anti-ferroelectric regime, where the essential singularity simil

T. Crenny, S. R. Federman

We used archival data acquired with the Copernicus satellite to reexamine CO column densities because self-consistent oscillator strengths are now available. Our focus is on lines of sight containing modest amounts of molecular species. Our resulting column densities are small enough that self-shielding from photodissociation is not occurring in the clouds p

R. M. Bandyopadhyay, K. M. Blundell, Ph. Podsiadlowski, J. C. A. Miller-Jones

We present early results from the first IR imaging of the weak X-ray sources discovered in a recent Chandra survey towards the Galactic Centre. From our VLT observations we will identify likely counterparts to a sample of the hardest sources in order to place constraints on the nature of this previously unknown population.

A. De Luca, S. Mereghetti, P. A. Caraveo, M. Moroni

In August 2002, XMM-Newton devoted two full orbits to the observation of 1E 1207.4-5209, making this isolated neutron star the most deeply scrutinized galactic target of the mission. Thanks to the high throughput of the EPIC instrument, ~360,000 photons were collected from the source, allowing for a very sensitive study of the temporal and spectral behaviour

Arthur D. Chernin

Cosmic internal symmetry (COINS) relates cosmic vacuum, dark matter, baryons and radiation, in a finite universe. Evidence for COINS comes from the concordance data, including the WMAP data. COINS is behind 1)the cosmic coincidence, 2)the spatial flatness, 3)cosmic entropy, 4)initial amplitude of cosmic perturbations. COINS suggests also a solution to the na

Piotr Magierski, Aurel Bulgac

In the inner crust of a neutron star, due to the high density and pressure, nuclei which are still present, are immersed in a neutron superfluid. One then expects that the dynamical properties of nuclei are significantly affected. In order to estimate the magnitude of the effect associated with the presence of a superfluid medium, we formulate the hydrodynam

Piotr Magierski

The inner crust of a neutron star consists of nuclei immersed in a superfluid neutron liquid. As these nuclei move through the fermionic medium they bring it into motion as well. As a result their mass is strongly renormalized and the spectrum of the ion lattice vibrations is significantly affected. Consequently we predict that the specific heat and the latt

Bon-Chul Koo, Ji-hyun Kang

We estimate the number of old, radiative supernova remnants (SNRs) detectable in HI 21-cm emission line in the Galaxy. According to our result, the contamination due to the Galactic background HI emission limits the number of visible SNRs to 270, or 9% of the total HI SNRs. The telescope sensitivity further limits the number. We compare the result with obser

M. W. Kalinowski

We consider a dynamics of Higgs&#39; field in the framework of cosmological models involving the scalar field from Nonsymmetric Kaluza-Klein (Jordan-Thiry) Theory. The field plays here a role of a quintessence field. We consider phase transition in cosmological models of the second and of the first order due to evolution of Higgs&#39; field. We developed inf

M. W. Kalinowski

We calculate a mass of a quintessence particle of order 0.00001 eV and we find several solutions for quintessence field equation. We consider also a quintessence speed of sound in several schemes and quintessence fluctuations.

Lie-Wen Chen, C. M. Ko, Zi-Wei Lin

Higher-order anisotropic flows $v_{4}$ and $v_{6}$ in heavy ion collisions at the Relativistic Heavy Ion Collider are studied in a multiphase transport model that has previously been used successfully for describing the elliptic flow $v_2$ in these collisions. We find that the same parton scattering cross section of about 10 \textrm{mb} used in explaining th

Robert Jaffe, Frank Wilczek

Theoretical considerations prompted by discovery of the exotic Theta(uudds*) baryon led us to propose a dynamical picture emphasizing the role of diquark correlations, which are also useful in elucidating other aspects of low-energy QCD. A notable prediction of this picture is the existence of new exotic and non-exotic S=-2 ``cascade&#39;&#39; baryons with s

Suresh K Maran

This article has been withdrawn.

David E. Miller, Abdel-Nasser M. Tawfik

We look at two well known examples of interacting systems relating to condensed matter in which we put the strong interacting parameters. At high quark chemical potentials and low temperatures we study the entropy arising from the excitation in the BCS model of superconductivity and the Bose-Einstein condensation (BEC) of colored quark pairs. We compare it w

P. Marecki

The quantum electrodynamics in presence of background external fields is developed. Modern methods of local quantum physics allow to formulate the theory on arbitrarily strong possibly time-dependent external fields. Non-linear observables which depend only locally on the external field are constructed. The tools necessary for this formulation, the parametri

Chi-Yi Chen, Kang Li, You-Gen Shen

The role that the auxiliary scalar field $ϕ$ played in Brans-Dicke cosmology is discussed. If a constant vacuum energy is assumed to be the origin of dark energy, then the corresponding density parameter would be a quantity varying with $ϕ$; and almost all of the fundamental components of our universe can be unified into the dynamical equation for $ϕ$. As a

G. Brida, M. Chekhova, M. Genovese, M. Gramegna

A conditioned unitary transformation ($90^o$ polarization rotation) is performed at single-photon level. The transformation is realized by rotating polarization for one of the photons of a polarization-entangled biphoton state (signal photon) by means of a Pockel&#39;s cell triggered by the detection of the other (idler) photon after polarization selection.

David Garfinkle

Numerical simulations of the approach to the singularity in vacuum spacetimes are presented here. The spacetimes examined have no symmetries and can be regarded as representing the general behavior of singularities. It is found that the singularity is spacelike and that as it is approached, the spacetime dynamics becomes local and oscillatory.

F. Pennini, A. Plastino

With the help of the coherent states&#39; basis we establish an interesting connection among i) the so-called Wehrl entropy, ii) Fisher&#39;s information measure $I$, and iii) the canonical ensemble entropy for the one-dimensional quantum harmonic oscillator (HO). We show that the contribution of the excited HO spectrum to the mean thermal energy is given by

D. Q. Lamb, T. Q. Donaghy, C. Graziani

HETE-2 has provided strong evidence that the properties of X-Ray Flashes (XRFs), X-ray-rich GRBs, and GRBs form a continuum, and therefore that these three kinds of bursts are the same phenomenon. A key feature found by HETE-2 is that the density of bursts is roughly constant per logarithmic interval in burst fluence S_E and observed spectral peak energy Ep_

L. Ya. Glozman

It is shown that experimental meson states with spins J=0,1,2,3 in the energy range 1.9 - 2.4 GeV obtained in recent partial wave analysis of proton-antiproton annihilation at LEAR remarkably confirm all predictions of chiral symmetry restoration. Classification of excited $\bar q q$ mesons according to the representations of chiral $U(2)_L \times U(2)_R$ gr

Naoki Kawashima, Kenji Harada

World-line quantum Monte Carlo methods are reviewed with an emphasis on breakthroughs made in recent years. In particular, three algorithms -- the loop algorithm, the worm algorithm, and the directed-loop algorithm -- for updating world-line configurations are presented in a unified perspective. Detailed descriptions of the algorithms in specific cases are a

K. Iida, T. Matsuura, M. Tachibana, T. Hatsuda

Thermal color superconducting phase transitions in high density three-flavor quark matter are investigated in the Ginzburg-Landau approach. Effects of nonzero strange quark mass, electric and color charge neutrality, and direct instantons are considered. Weak coupling calculations show that an interplay between the mass and electric neutrality effects near t

Aaron Clauset, Cristopher Moore

The topology of the Internet has typically been measured by sampling traceroutes, which are roughly shortest paths from sources to destinations. The resulting measurements have been used to infer that the Internet&#39;s degree distribution is scale-free; however, many of these measurements have relied on sampling traceroutes from a small number of sources. I

Kazuhiro Kuboki, Hidenori Takahashi

We study theoretically the proximity effect between ferromagnets (F) and superconductors (S) with broken time-reversal symmetry (${\cal T}$). A chiral $(p_x\pm ip_y)$-wave, and a $d_{x^2-y^2}$-wave superconductor, the latter of which can form ${\cal T}$-breaking surface state, i.e., $(d_{x^2-y^2} \pm is)$-state, are considered for the S side. The spatial var