January 2006 arXiv papers — page 38

Yi Qi, H. Zheng, R. Ramesh, Steven M. Anlage

We report on linear and non-linear dielectric property measurements of BaTiO3 - CoFe2O4 (BTO-CFO) ferroelectro-magnetic nano-composites and pure BaTiO3 and CoFe2O4 samples with Scanning Near Field Microwave Microscopy. The permittivity scanning image with spatial resolution on the micro-meter scale shows that the nano-composites have very uniform quality wit

Jason X. Prochaska, Hsiao-Wen Chen, Joshua S. Bloom

We investigate properties of the interstellar medium (ISM) in galaxies hosting long-duration gamma-ray bursts (GRBs) from an analysis of atomic species (MgI, FeI) and excited fine-structure levels of ions (e.g. SiII). Our analysis is guided primarily by echelle observations of GRB 050730 and GRB 051111. These sightlines exhibit fine-structure transitions of

Eric V. Linder

The structure of the dark energy equation of state phase plane holds important information on the nature of the physics. We explain the bounds of the freezing and thawing models of scalar field dark energy in terms of the tension between the steepness of the potential vs. the Hubble drag. Additionally, we extend the phase plane structure to modified gravity

Kuo-An Wu, Alain Karma, Jeffrey J. Hoyt, Mark Asta

The weak anisotropy of the interfacial free-energy $γ$ is a crucial parameter influencing dendritic crystal growth morphologies in systems with atomically rough solid-liquid interfaces. The physical origin and quantitative prediction of this anisotropy are investigated for body-centered-cubic (bcc) forming systems using a Ginzburg-Landau theory where the ord

H. Egiyan, I. G. Aznauryan, V. D. Burkert, K. A. Griffioen

The ep -> e&#39;pi^+n reaction was studied in the first and second nucleon resonance regions in the 0.25 GeV^2 < Q^2 < 0.65 GeV^2 range using the CLAS detector at Thomas Jefferson National Accelerator Facility. For the first time the absolute cross sections were measured covering nearly the full angular range in the hadronic center-of-mass frame. The structu

Manoel M. Ferreira, Fernando M. O. Moucherek

The influence of Lorentz- and CPT-violating terms (in &#34;vector&#34; and &#34;axial vector&#34; couplings) on the Dirac equation is explicitly analyzed: plane wave solutions, dispersion relations and eigenenergies are explicitly obtained. The non-relativistic limit is worked out and the Lorentz-violating Hamiltonian identified in both cases, in full agreem

S. J. Yennello, D. V. Shetty, G. A. Souliotis

The symmetry energy is an important quantity in the equation of state of isospin asymmetric nuclear matter. This currently unknown quantity is key to understanding the structure of systems as diverse as the neutron-rich nuclei and neutron stars. At TAMU, we have carried out studies, aimed at understanding the symmetry energy, in a variety of reactions such a

S. Kaviraj, S. -C. Rey, R. M. Rich, Y. -W. Lee

We demonstrate that the combination of GALEX UV photometry in the FUV (~1530 angstroms) and NUV (~2310 angstroms) passbands with optical photometry in the standard U,B,V,R,I filters can efficiently break the age-metallicity degeneracy. We estimate well-constrained ages, metallicities and their associated errors for 42 GCs in M31, and show that the full set o

Raoul-Martin Memmesheimer, Marc Timme

Precise timing of spikes and temporal locking are key elements of neural computation. Here we demonstrate how even strongly heterogeneous, deterministic neural networks with delayed interactions and complex topology can exhibit periodic patterns of spikes that are precisely timed. We develop an analytical method to find the set of all networks exhibiting a p

Zoltan Nagy, Davison E. Soper

In this paper we outline a new parton shower algorithm based on the Catani-Seymour dipole factorization. Our motivation is to have an algorithm which can naturally cooperate with the NLO calculations.

J. A. Morgan

The spin-statistics connection is obtained for a simple formulation of a classical field theory containing even and odd Grassmann variables. To that end, the construction of irreducible canonical realizations of the rotation group corresponding to general causal fields is reviewed. The connection is obtained by imposing local commutativity on the fields and

Chuan-Hung Chen

Inspired by the small longitudinal polarizations (LPs) of $B\to K^* ϕ$ decays observed by BELLE and BABAR, we revise the theoretical uncertainties of perturbative QCD approach for determining hard scales of B decays, we find that the LPs of $B\to K^* ϕ$ could approach to 60% while the branching ratios (BRs) could be around $9\times 10^{-6}$. In addition, we

M. Grendar

In this paper we study the exponential decay of posterior probability of a set of sources and conditioning by rare sources for both uniform and general prior distributions of sources. The decay rate is determined by $L$-divergence and rare sources from a convex, closed set asymptotically conditionally concentrate on an $L$-projection. $L$-projection on a lin

H. E. Jackson

The helicity distribution of the strange quark sea in the proton has been extracted from measurements of polarized production of charged kaons in deep-inelastic scattering from a polarized deuterium target.

Fedwa El-Mellouhi, Normand Mousseau

The dominant charge state for the Ga vacancy in GaAs has been the subject of a long debate, with experiments proposing $-$1, $-$2 or $-$3 as the best answer. We revisit this problem using {\it ab initio} calculations to compute the effects of temperature on the Gibbs free energy of formation, and we find that the thermal dependence of the Fermi level and of

Bernard S. Kay

An encyclopedia article on mathematical aspects of quantum field theory in curved spacetime. Section titles are: Introduction and preliminaries; Construction of *-algebra for a real linear scalar field on globally hyperbolic spacetimes and some general theorems; Particle creation and the limitations of the particle concept; Theory of the stress-energy tensor

Fei Wang, Wenyu Wang, Jin Min Yang

We split the two-Higgs-doublet model by assuming very different vevs for the two doublets: the vev is at weak scale (174 GeV) for the doublet Φ_1 and at neutrino-mass scale (10^{-2} \sim 10^{-3} eV) for the doublet Φ_2. Φ_1 is responsible for giving masses to all fermions except neutrinos; while Φ_2 is responsible for giving neutrino masses through its tiny

Xiang Liu, Yan-Ming Yu, Shu-Min Zhao, Xue-Qian Li

Based on the assumption that $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ are the $(0^+, 1^+)$ chiral partners of $D_{s}$ and $D^*_s$, we evaluate the strong pionic and radiative decays of $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ in the Constituent Quark Meson (CQM) model. Our numerical results of the relative ratios of the decay widths are reasonably consistent with

Omar Mustafa, S. Habib Mazharimousavi

A class of spherically symmetric non-Hermitian Hamiltonians and their η-weak-pseudo-Hermiticity generators are presented. An operators-based procedure is introduced so that the results for the 1D Schrodinger Hamiltonian may very well be reproduced. A generalization beyond the nodeless states is proposed. Our illustrative examples include η-weak-pseudo-Hermit

J. M. Aldaz, J. Pérez Lázaro

We prove that if $f:I\subset \Bbb R\to \Bbb R$ is of bounded variation, then the noncentered maximal function $Mf$ is absolutely continuous, and its derivative satisfies the sharp inequality $\|DMf\|_1\le |Df|(I)$. This allows us obtain, under less regularity, versions of classical inequalities involving derivatives.

G. Gallavotti

Entropy creation rate is introduced for a system interacting with thermostats ({\it i.e.}, in the usual language, for a system subject to internal conservative forces interacting with ``external&#39;&#39; thermostats via conservative forces) and a fluctuation theorem for it is proved. As an application a time scale is introduced, to be interpreted as the tim

V. Hinkov, P. Bourges, S. Pailhes, Y. Sidis

A detailed inelastic neutron scattering study of the in-plane anisotropy of magnetic excitations in twin-free YBa$_2$Cu$_3$O$_{6.6}$ ($T_c =$ 61 K) reveals that the spin excitation spectra in the superconducting and normal states are qualitatively different. Below $T_c$, the spectrum consists of upward- and downward-dispersing branches with modest in-plane a

Fabio Finelli, Matteo Galaverni, Alessandro Gruppuso

We study the bending of light for static spherically symmetric (SSS) space-times which include a dark energy contribution. Geometric dark energy models generically predict a correction to the Einstein angle written in terms of the distance to the closest approach, whereas a cosmological constant $Λ$ does not. While dark energy is associated with a repulsive

Mohsen Alishahiha, Hajar Ebrahim

We study the entropy of non-supersymmetric extremal black holes which exhibit attractor mechanism by making use of the entropy function. This method, being simple, can be used to calculate corrections to the entropy due to higher order corrections to the action. In particular we apply this method for five dimensional non-supersymmetric extremal black hole wh

Tobias J. Osborne

We show that adiabatic evolution of a low-dimensional lattice of quantum spins with a spectral gap can be simulated efficiently. In particular, we show that as long as the spectral gap ΔE between the ground state and the first excited state is any constant independent of n, the total number of spins, then the ground-state expectation values of local operator

Alice Guionnet, Edouard Maurel-Segala

We study several-matrix models and show that when the potential is convex and a small perturbation of the Gaussian potential, the first order correction to the free energy can be expressed as a generating function for the enumeration of maps of genus one. In order to do that, we prove a central limit theorem for traces of words of the weakly interacting rand

A. P. Baeta Scarpelli, J. A. Helayel-Neto

In this paper, we extend the analysis of the Lorentz-violating Quantum Eletrodynamics to the non-Abelian case: an SO(3) Yang-Mills Lagrangian with the addition of the non-Abelian Chern-Simons-type term. We consider the spontaneous symmetry breaking of the model and inspect its spectrum in order to check if unitarity and causality are respected. An analysis o

H. Fan, B. Y. Liu, K. J. Shi

Quantum cloning of two identical mixed qubits $ρ\otimes ρ$ is studied. We propose the quantum cloning transformations not only for the triplet (symmetric) states but also for the singlet (antisymmetric) state. We can copy these two identical mixed qubits to M (M>2) copies. This quantum cloning machine is optimal in the sense that the shrinking factor between

George Lazarides

We review the main proposals of particle physics for the composition of the cold dark matter in the universe. Strong axion contribution to cold dark matter is not favored if the Peccei-Quinn field emerges with non-zero value at the end of inflation and the inflationary scale is superheavy since, under these circumstances, it leads to unacceptably large isocu

Claudio Altafini

The feedback stabilization problem for ensembles of coupled spin 1/2 systems is discussed from a control theoretic perspective. The noninvasive nature of the bulk measurement allows for a fully unitary and deterministic closed loop. The Lyapunov-based feedback design presented does not require spins that are selectively addressable. With this method, it is p

Lars Nilse

We present a complete classification of all 1D and 2D orbifold compactifications. There exist 2 one-dimensional and 17 two-dimensional orbifolds. The classification includes orbifolds such as S^1/Z_2 or T^2/Z_n, as well as less familiar ones like T^2/D_n or the Mobius strip. We derive the explicit form of the basis functions and prove their orthonormality an

M. Blagojevic, B. Cvetkovic

The role of torsion in quantum three-dimensional gravity is investigated by studying the partition function of the Euclidean theory in Riemann-Cartan spacetime. The entropy of the black hole with torsion is found to differ from the standard Bekenstein-Hawking result, but its form is in complete agreement with the first law of black hole thermodynamics.

S. Rajasekar, P. Philominathan, V. Chinnathambi

In this manuscript various components of research are listed and briefly discussed. The topics considered in this write-up cover a part of the research methodology paper of Master of Philosophy (M.Phil.) course and Doctor of Philosophy (Ph.D.) course. The manuscript is intended for students and research scholars of science subjects such as mathematics, physi

H. Mouri, Y. Taniguchi

There is observed a trend that a lower mass galaxy forms stars at a later epoch. This downsizing of star-forming galaxies has been attributed to hydrodynamical or radiative feedback processes that regulate star formation. However, here we explain the downsizing by gravitational processes alone, in the bottom-up scenario where galaxies evolve from subgalactic

Eric Bertin, Michel Droz, Guillaume Gregoire

We study analytically the emergence of spontaneous collective motion within large bidimensional groups of self-propelled particles with noisy local interactions, a schematic model for assemblies of biological organisms. As a central result, we derive from the individual dynamics the hydrodynamic equations for the density and velocity fields, thus giving a mi

Shige Peng

We introduce a notion of nonlinear expectation --G--expectation-- generated by a nonlinear heat equation with infinitesimal generator G. We first discuss the notion of G-standard normal distribution. With this nonlinear distribution we can introduce our G-expectation under which the canonical process is a G--Brownian motion. We then establish the related sto

B J Dalton

A theory of BEC interferometry in an unsymmetrical double-well trap has been developed for small boson numbers, based on the two-mode approximation. The bosons are initially in the lowest mode of a single well trap, which is split into a double well and then recombined. Possible fragmentations into separate BEC states in each well during the splitting/recomb

Neil P. Oxtoby, H. M. Wiseman, He-Bi Sun

We consider charge-qubit monitoring (continuous-in-time weak measurement) by a single-electron transistor (SET) operating in the sequential-tunneling regime. We show that commonly used master equations for this regime are not of the Lindblad form that is necessary and sufficient for guaranteeing valid physical states. In this paper we derive a Lindblad-form

Xiaohu Yang, Frank C. van den Bosch, H. J. Mo, Shude Mao

We use galaxy groups selected from the Sloan Digital Sky Survey to examine the alignment between the orientation of the central galaxy (defined as the brightest group member) and the distribution of satellite galaxies. By construction, we therefore only address the alignment on scales smaller than the halo virial radius. We find a highly significant alignmen

Kenneth R. Brown, Robert J. Clark, Isaac L. Chuang

Quantum simulation uses a well-known quantum system to predict the behavior of another quantum system. Certain limitations in this technique arise, however, when applied to specific problems, as we demonstrate with a theoretical and experimental study of an algorithm to find the low-lying spectrum of a Hamiltonian. While the number of elementary quantum gate

Dorje C. Brody, Lane P. Hughston

Space-time symmetries and internal quantum symmetries can be placed on equal footing in a hyperspin geometry. Four-dimensional classical space-time emerges as a result of a decoherence that disentangles the quantum and the space-time degrees of freedom. A map from the quantum space-time to classical space-time that preserves the causality relations of space-

Alexander Stibor, Andre Stefanov, Fabienne Goldfarb, Elisabeth Reiger

Imaging of surface adsorbed molecules is investigated as a novel detection method for matter wave interferometry with fluorescent particles. Mechanically magnified fluorescence imaging turns out to be an excellent tool for recording quantum interference patterns. It has a good sensitivity and yields patterns of high visibility. The spatial resolution of this

Milos V. Lokajicek

The support of Copenhagen quantum mechanics in the discussion concerning EPR experiments has been based fundamentally on two mistakes. First, quantum mechanics as well as hidden-variable theory give the same predictions; the statement of Belinfante from 1973 about the significant difference must be denoted as mistake. Secondly, the experimental violation of

H. S. Eisenberg, J. F. Hodelin, G. Khoury, D. Bouwmeester

The bunching of two single photons on a beam-splitter is a fundamental quantum effect, first observed by Hong, Ou and Mandel. It is a unique interference effect that relies only on the photons&#39; indistinguishability and not on their relative phase. We generalize this effect by demonstrating the bunching of two Bell states, created in two passes of a nonli

Klaus Dietz

m-Qubit states are imbedded in $\mathfrak{Cl}_{2^m}$ Clifford algebras. Their probability spectra then depend on $O(2m)$ or $O(2m+1)$ invariants. Parameter domains for $O(2m(+1))-$ vector and tensor configurations, generalizing the notion of a Bloch sphere, are derived.

Matti Selg

A recently proposed reference potential approach to the inverse Schrödinger problem is further developed. As previously, theoretical developments are demonstrated on example of diatomic xenon molecule in its ground electronic state. An exactly solvable reference potential for this quantum system is used, which enables to solve the related energy eigenvalue p

Simon Anders, Hans J. Briegel

According to the Gottesman-Knill theorem, a class of quantum circuits, namely the so-called stabilizer circuits, can be simulated efficiently on a classical computer. We introduce a new algorithm for this task, which is based on the graph-state formalism. It shows significant improvement in comparison to an existing algorithm, given by Gottesman and Aaronson

H. S. Eisenberg, J. F. Hodelin, G. Khoury, D. Bouwmeester

Multiphoton path entanglement is created without applying post-selection, by manipulating the state of stimulated parametric down-conversion. A specific measurement on one of the two output spatial modes leads to the non-local bunching of the photons of the other mode, forming the desired multiphoton path entangled state. We present experimental results for

Paul Smolen, Douglas A. Baxter, John H. Byrne

The induction of late long-term potentiation (L-LTP) involves complex interactions among second messenger cascades. To gain insights into these interactions, a mathematical model was developed for L-LTP induction in the CA1 region of the hippocampus. The differential equation-based model represents actions of protein kinase A (PKA), MAP kinase (MAPK), and Ca

John Krizmanic, Brian Morgan, Robert Streitmatter, Neil Gehrels

Diffractive/refractive optics, such as Phase Fresnel Lenses (PFL&#39;s), offer the potential to achieve excellent imaging performance in the x-ray and gamma-ray photon regimes. In principle, the angular resolution obtained with these devices can be diffraction limited. Furthermore, improvements in signal sensitivity can be achieved as virtually the entire fl

F. Stefani, G. Gerbeth, U. Guenther

The irregular polarity reversals of the Earth&#39;s magnetic field have attracted much interest during the last decades. Despite the fact that recent numerical simulations of the geodynamo have shown nice polarity transitions, the very reason and the basic mechanism of reversals are far from being understood. Using a paradigmatic mean-field dynamo model with

Avshalom C. Elizur, Meir Shinitzky

P-violation of the nuclear weak force was hitherto believed to manifest itself only in asymmetric $β$-emission due to neutron decay. Molecules with space asymmetry (like L and D amino acids) are affected by this parity violation, yielding a parity violation energy difference (PVED) between chiral isomers in the order of $10^{-16}$ ev. In specific cases, wher

Michaël Sanrey, Marc Joyeux, Dmitrii A. Sadovskii

Classical plane switching takes place in systems with a pronounced 1:2 resonance, where the degree of freedom with lowest frequency is doubly-degenerate. Under appropriate conditions, one observes a periodic and abrupt precession of the plane in which the doubly-degenerate motion takes place. In this article, we show that quantum plane switching exists in CO

Jianhua Xiao

Many researches show that the complicated motion of fluid, such as turbulence, cannot be well solved by the Navier-Stokes equation. Chen Zida has founded that the definition of vortex, based on the Stokes decomposition, cannot well describe the local rotation when the velocity gradient is highly asymmetric. Chen reformulates the Stokes S+R decomposition into

Zao-Chun Gao, Y. S. Chen, Yang Sun

A possible scheme of realizing shell model calculations for heavy nuclei is based on a deformed basis and the projection technique. Here we present a new development for odd-odd nuclei, in which one starts with triaxially-deformed multi-quasi-particle configurations, builds the shell-model space through exact three-dimensional angular-momentum-projection, an

Franjo Krmpotić

The possibility of applying the Quasiparticle Tamm-Dancoff Approximation (QTDA) to describe the nuclear double beta decay is explored. Several serious inconveniences found in the Quasiparticle Random Phase Approximation (QRPA), such as: i) the extreme sensitivity of the $2νββ$ decay amplitudes ${\cal M}_{2ν}$ on the residual interaction in the particle-parti

Tetsufumi Hirano

We can establish a new picture, the perfect fluid sQGP core and the dissipative hadronic corona, of the space-time evolution of produced matter in relativistic heavy ion collisions at RHIC. It is also shown that the picture works well also in the forward rapidity region through an analysis based on a new class of the hydro-kinetic model and is a manifestatio

T. Niksic, D. Vretenar, P. Ring

We report the first study of restoration of rotational symmetry and fluctuations of the quadrupole deformation in the framework of relativistic mean-field models. A model is developed which uses the generator coordinate method to perform configuration mixing calculations of angular momentum projected wave functions, calculated in a relativistic point-couplin

G. Baur, S. Typel

Indirect methods in nuclear astrophysics are discussed. Recent work on Coulomb dissociation and an effective-range theory of low-lying electromagnetic strength of halo nuclei is presented. Coulomb dissociation of a halo nucleus bound by a zero-range potential is proposed as a homework problem (for further references see G. Baur and S. Typel, nucl-th/0504068)

F. Huang, Z. Y. Zhang, Y. W. Yu

Using the resonating group method (RGM), we dynamically study the baryon-meson interactions in chiral quark model. Some interesting results are obtained: (1) The Sigma K state has an attractive interaction, which consequently results in a Sigma K quasibound state. When the channel coupling of Sigma K and Lambda K is considered, a sharp resonance appears betw

Takao Sakaguchi

Direct photon production in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV has been measured. The result is compared to several theoretical calculations, and found that it is not inconsistent with ones including thermal radiation from QGP or jet-photon conversion process on top of a NLO pQCD expectation. The direct photon contribution in dilepton measurement is

Jahanshah Davoudi, Joerg Schumacher

We present numerical studies of stretching of Hookean dumbbells in a turbulent Navier-Stokes flow with a linear mean profile, <u_x>=Sy. In addition to the turbulence features beyond the viscous Kolmogorov scale η, the dynamics at the equilibrium extension of the dumbbells significantly below eta is well resolved. The variation of the constant shear rate S ca

N M J Woodhouse

By an extension of Harnad&#39;s and Dubrovin&#39;s `duality&#39; constructions, the general isomonodromy problem studied by Jimbo, Miwa, and Ueno is equivalent to one in which the linear system of differential equations has a regular singularity at the origin and an irregular singularity at infinity (both resonant). The paper looks at this dual formulation o

Jochen Fromm

The engineering and design of self-organizing systems with emergent properties is a long-standing problem in the field of complex and distributed systems, for example in the engineering of self-organizing Multi-Agent Systems. The problem of combining engineering with emergence - to find a simple rule for a complex pattern - equals the problem of science in g

Alex H. Barnett

Consider the Laplacian in a bounded domain in R^d with general (mixed) homogeneous boundary conditions. We prove that its eigenfunctions are `quasi-orthogonal&#39; on the boundary with respect to a certain norm. Boundary orthogonality is proved asymptotically within a narrow eigenvalue window of width o(E^{1/2}) centered about E, as E->infinity. For the spec

Alain Connes, Matilde Marcolli

This text is written for the volume of the school/conference &#34;Noncommutative Geometry 2005&#34; held at IPM Tehran. It gives a survey of methods and results in noncommutative geometry, based on a discussion of significant examples of noncommutative spaces in geometry, number theory, and physics. The paper also contains an outline (the ``Tehran program&#3

Salman Abdulali

We show that any effective Hodge structure of CM-type occurs (without having to take a Tate twist) in the cohomology of some CM abelian variety over C. As a consequence we get a simple proof of the theorem (due to Hazama) that the usual Hodge conjecture for the class of all CM abelian varieties implies the general Hodge conjecture for the same class.

Siegfried Echterhoff, Dana P. Williams

We study conditions on a $C^*$-dynamical system $(A,G,α)$ under which induction of primitive ideals (resp. irreducible representations) from stabilizers for the action of $G$ on the primitive ideal space $\Prim(A)$ give primitive ideals (resp. irreducible representations) of the crossed product $A\rtimes_αG$. The results build on earlier results of Sauvageot

Yuuki Abe, Toshiki Nakashima

The purpose of this paper is to compute the Drinfel&#39;d polynomials for two types of evaluation representations of quantum affine algebras at roots of unity and construct those representations as the submodules of evaluation Schnizer modules. Moreover, we obtain the necessary and sufficient condition for that the two types of evaluation representations are

A. Shapiro, S. Kaplan, M. Teicher

The notion of Bezout matrix is an essential tool in studying broad variety of subjects: zeroes of polynomials, stability of differential equations, rational transformations of algebraic curves, systems of commuting nonselfadjoint operators, boundaries of quadrature domains etc. We present a survey of several properties of Bezout matrices and their applicatio

Andreas Thom

We analyze the algebraic structure of the Connes fusion tensor product (CFTP) in the case of bi-finite Hilbert modules over a von Neumann algebra M. It turns out that all complications in its definition disappear if one uses the closely related bi-modules of bounded vectors. We construct an equivalence of monoidal categories with duality between a category o

Yulij Ilyashenko

An upper bound of the variation of argument of a holomorphic function along a curve on a Riemann surface is given. This bound is expressed through the Bernstein index of the function multiplied by a geometric constant. The Bernstein index characterizes growth of the function from a smaller domain to a larger one. The geometric constant in the estimate is exp

N. S. Dairbekov, G. P. Paternain

We show that an arbitrary Anosov Gaussian thermostat on a surface is dissipative unless the external field has a global potential.

Steven Dale Cutkosky

Suppose that $f:X\to Y$ is a dominant morphism of 3-folds over an algebraically closed field of characteristic zero. We prove that there exist sequences of blow ups of points and nonsingular curves $Φ:X_1\to X$ and $Ψ:Y_1\to Y$ such that the induced map $f_1:Y_1\to X_1$ is a toroidal morphism. This extends an earlier proof of the author of this theorem with

Randal Douc, Arnaud Guillin, Eric Moulines

This paper studies limit theorems for Markov Chains with general state space under conditions which imply subgeometric ergodicity. We obtain a central limit theorem and moderate deviation principles for additive not necessarily bounded functional of the Markov chains under drift and minorization conditions which are weaker than the Foster-Lyapunov conditions

Patrick Boily

Spirals are common in Nature: the snail&#39;s shell and the ordering of seeds in the sunflower are amongst the most widely-known occurrences. While these are static, dynamic spirals can also be observed in excitable systems such as heart tissue, retina, certain chemical reactions, slime mold aggregates, flame fronts, etc. The images associated with these spi

David Fisher, Theron Hitchman

We announce a generalization of Zimmer&#39;s cocycle superrigidity theorem proven using harmonic map techniques. This allows us to generalize many results concerning higher rank lattices to all lattices in semisimple groups with property $(T)$. In particular, our results apply to SP(1,n) and $F_4^{-20}$ and lattices in those groups. The main technical step i

A. Martinez-Finkelshtein

This is an expanded version of the talk given at the conference ``Constructive Functions Tech-04&#39;&#39;. We survey some recent results on canonical representation and asymptotic behavior of polynomials orthogonal on the unit circle with respect to an analytic weight. These results are obtained using the steepest descent method based on the Riemann-Hilbert

T. D. Browning, D. R. Heath-Brown

Let $X \subset \mathbb{P}^n$ be a non-singular hypersurface of degree $d>1$, and let $ε>0$. This paper is concerned with the conjecture that there are $O(B^{n-1+ε})$ rational points on $X$ that have height at most $B$, in which the implied constant is allowed to depend only upon $d, ε$ and $n$. In particular this conjecture is shown to hold as soon as $d>4$.

Petr P. Kulish, Anton M. Zeitlin

The quantization procedure for both N=1 and N=2 supersymmetric Korteweg-de Vries (SUSY KdV) hierarchies is constructed. Namely, the quantum counterparts of the monodromy matrices, built by means of the integrated vertex operators, are shown to satisfy a specialization of reflection equation, leading to the quantum integrable theory. The relation of such mode

Giampiero Esposito, Guglielmo Fucci, Alexander Yu. Kamenshchik, Klaus Kirsten

A general method exists for studying Abelian and non-Abelian gauge theories, as well as Euclidean quantum gravity, at one-loop level on manifolds with boundary. In the latter case, boundary conditions on metric perturbations h can be chosen to be completely invariant under infinitesimal diffeomorphisms, to preserve the invariance group of the theory and BRST

Richard F. Lebed

This talk outlines recent advances using QCD in the 1/N_c limit aimed at understanding baryon scattering processes and their embedded short-lived baryon resonances. In this presentation we emphasize developing qualitative physical insight over presenting results of detailed calculations.

Stanley F Radford, Wayne W. Repko

We examine the spectra and radiative decays of the cc-bar and bb-bar systems using a model which incorporates the complete one-loop spin-dependent perturbative QCD short distance potential, a linear confining term including (spin-dependent) relativistic corrections to order v^2/c^2, and a fully relativistic treatment of the kinetic energy. We compare the pre

Tomohiro Matsuda

Cosmic strings in the brane Universe have recently gained a great interest. I think the most interesting story is that future cosmological observations distinguish them from the conventional cosmic strings. If the strings are the higher-dimensional objects that can (at least initially) move along the compactified space, and finally settle down to (quasi-)deg

Namit Mahajan

This paper has been withdrawn by the author.

Jiri Chyla

The QCD corrections to photon structure functions are defined in a way consistent with the factorization scheme invariance. It is shown that the conventional DIS$_γ$ factorization scheme does not respect this invariance and is thus deeply flawed. The origins of the divergent behavior of photonic coefficient function at large $x$ are analyzed and recipe to re

M. Göckeler, R. Horsley, A. C. Irving, D. Pleiter

We present a determination of the strange quark mass for two flavours (nf=2) of light dynamical quarks using the axial Ward identity. The calculations are performed on the lattice using O(a) improved Wilson fermions and include a fully non-perturbative determination of the renormalisation constant. In the continuum limit we find in the MSbar scheme at 2GeV,

David H. Miller

Using the CLEO-c detector and a data sample of 0.8 million D+D- pairs at the Psi(3770) a search has been performed for flavor changing neutral current and lepton number violating decays of D+ mesons to final states with dielectrons. No signals are observed and 90% confidence limits are set for specific decay modes in the range of a few times ten to the minus

J. M. Butterworth

QCD is the accepted (that is, the effective) theory of the strong interaction; studies at colliders are no longer designed to establish this. Such studies can now be divided into two categories. The first involves the identification of observables which can be both measured and predicted at the level of a few percent. Such studies parallel those of the elect

J. Menezes, P. P. Avelino, C. Santos

We study spatial variations of the fine-structure constant in the presence of static straight cosmic strings in the weak-field approximation in Einstein gravity. We work in the context of a generic Bekenstein-type model and consider a gauge kinetic function linear in the scalar field. We determine an analytical form for the scalar field and the string metric

F. Rahaman, R. Mondal, M. Kalam

We investigate a local cosmic string with a phenomenological energy momentum tensor as prescribed by Vilenkin, in presence of C-field . The solutions of full nonlinear Einstein&#39;s equations for exterior and interior regions of such a string are presented.

Sang Pyo Kim

After explaining the physical origin of the quasinormal modes of perturbations in the background geometry of a black hole, I critically review the recent proposal for the quantization of the black-hole area based on the real part of quasinormal modes. As instantons due to the barriers of black-hole potentials lie at the root of a discrete set of complex quas

Jean-Pierre Gazeau, Marc Lachieze-Rey, Wlodzimierz Piechocki

We compare the respective efficiencies of three quantization methods (group theoretical, coherent state and geometric) by quantizing the dynamics of a free massive particle in two-dimensional de Sitter space. For each case we consider the realization of the principal series representation of $SO_0(1,2) $ group and its two-fold covering SU(1,1). We demonstrat

Benoît Girard, David Filliat, Jean-Arcady Meyer, Alain Berthoz

This article describes a biomimetic control architecture affording an animat both action selection and navigation functionalities. It satisfies the survival constraint of an artificial metabolism and supports several complementary navigation strategies. It builds upon an action selection model based on the basal ganglia of the vertebrate brain, using two int

T. Emig, R. L. Jaffe, M. Kardar, A. Scardicchio

We find the exact Casimir force between a plate and a cylinder, a geometry intermediate between parallel plates, where the force is known exactly, and the plate--sphere, where it is known at large separations. The force has an unexpectedly weak decay \sim L/(H^3 \ln(H/R)) at large plate--cylinder separations H (L and R are the cylinder length and radius), du

C. Regal, D. S. Jin

This thesis presents experiments probing physics in the crossover between Bose-Einstein condensation (BEC) and BCS superconductivity using an ultracold gas of atomic fermions. Scattering resonances in these ultracold gases (known as Feshbach resonances) provide the unique ability to tune the fermion-fermion interactions. The work presented here pioneered the

Alina Ciach

A coarse-grained description of the restricted primitive model is considered in terms of the local charge- and number-density fields. Exact reduction to a one-field theory is derived, and exact expressions for the number-density correlation functions in terms of higher-order correlation functions for the charge-density are given. It is shown that in continuu

S. C. Ferreira, S. O. Ferreira

Recent experiments involving CdTe films grown on Si(111) substrates by hot wall epitaxy revealed features not previously observed [S. O. Ferreira \textit{et al.}, J. Appl. Phys. \textbf{93}, 1195 (2003)]. This system, which follows the Volmer-Weber growth mode with nucleation of isolated 3D islands for less than one monolayer of evaporated material, was desc

Srdjan Ostojic, Ellak Somfai, Bernard Nienhuis

Force networks form the skeleton of static granular matter. They are the key ingredient to mechanical properties, such as stability, elasticity and sound transmission, which are of utmost importance for civil engineering and industrial processing. Previous studies have focused on the global structure of external forces (the boundary condition), and on the pr

N. M. Oliveira-Neto, E. M. F. Curado, F. D. Nobre, M. A. Rego-Monteiro

The dynamics of the approach to equilibrium of the hydrogen atom is investigated numerically through a Monte Carlo procedure. We show that, before approaching ionization, the hydrogen atom may live in a quasi-equilibrium state, characterized by aging, whose duration increases exponentially as the temperatures decreases. By analyzing the quasi-equilibrium sta