September 2005 arXiv papers — page 5

Frank Bensch, Gary J. Melnick, David A. Neufeld, Martin Harwit

On 4 July 2005 at 1:52 UT the Deep Impact mission successfully completed its goal to hit the nucleus of 9P/Tempel 1 with an impactor, forming a crater on the nucleus and ejecting material into the coma of the comet. The 370 kg impactor collided with the sunlit side of the nucleus with a relative velocity of 10.2 km/s. NASA's Submillimeter Wave Astronomy

Peter Wolf, Fréderic Chapelet, Sebastien Bize, Andre Clairon

Lorentz Invariance (LI) is the founding postulate of Einstein's 1905 theory of relativity, and therefore at the heart of all accepted theories of physics. It characterizes the invariance of the laws of physics in inertial frames under changes of velocity or orientation. This central role, and indications from unification theories hinting toward a possibl

Andrei Moroianu

Motivated by the possible characterization of Sasakian manifolds in terms of twistor forms, we give the complete classification of compact Riemannian manifolds carrying a Killing vector field whose covariant derivative (viewed as a 2-form) is a twistor form.

Ashish Saxena, Geoff Potvin, Stefano Giusto, Amanda W. Peet

A class of axially symmetric, rotating four-dimensional geometries carrying D1, D5, KK monopole and momentum charges is constructed. The geometries are found to be free of horizons and singulaties, and are candidates to be the gravity duals of microstates of the (0,4) CFT. These geometries are constructed by performing singularity analysis on a suitably chos

Laurent Bartholdi, Benjamin Enriquez, Pavel Etingof, Eric Rains

For a positive integer n we introduce quadratic Lie algebras tr_n qtr_n and discrete groups Tr_n, QTr_n naturally associated with the classical and quantum Yang-Baxter equation, respectively. We prove that the universal enveloping algebras of the Lie algebras tr_n, qtr_n are Koszul, and find their Hilbert series. We also compute the cohomology rings of these

Eric Swanson

The status of some of the recently discovered heavy hadrons is presented.

Jesper Sommer-Larsen

Cosmological LCDM simulations of 12 M_vir~10^14 Msun galaxy groups have been performed, invoking star formation, chemical evolution with non-instantaneous recycling, metallicity dependent radiative cooling, strong star-burst driven galactic super-winds and effects of a meta-galactic UV field. At z=0, intra-group light (IGL) fractions are found to be 12-45%.

Grigol Gogoberidze

It is shown that in the presence of anisotropic kinetic dissipation existence of scale invariant power law spectrum of plasma turbulence is possible. Obtained scale invariant spectrum is not associated with the constant flux of any physical quantity. Application of the model to the high frequency part of the solar wind turbulence is discussed.

Dariusz Prorok

The global variables like the transverse energy at midrapidity, the charged particle multiplicity at midrapidity and the total multiplicity of charged particles are evaluated in the single-freeze-out statistical model for different centrality bins at RHIC at $\sqrt{s_{NN}}=130$ and 200 GeV. Full description of decays of hadron resonances is applied in these

E. Koulouridis, M. Plionis, V. Chavushyan, D. Dultzin-Hacyan

We present a three-dimensional study of the local (<100 h^-1} kpc) and the large scale (<1 h^{-1} Mpc) environment of the two main types of Seyfert AGN galaxies. For this purpose we use 48 Sy1 galaxies (with redshifts in the range 0.007<z<0.036) and 56 Sy2 galaxies (with 0.004<z<0.020), located at high galactic latitudes, as well as two control samples of no

Kamil Walczak

Electrical conduction through a two-terminal molecular device is studied using non-equilibrium Green&#39;s functions (NEGF) formalism. Such junction is made of a short linear wire which is connected to the metallic electrodes. Molecule itself is described with the help of Huckel (tight-binding) model with the electron interactions treated within extended Hub

P. H. Chavanis

We discuss the nature of quasi-stationary states (QSS) with non-Boltzmannian distribution in systems with long-range interactions in relation with a process of incomplete violent relaxation based on the Vlasov equation. We discuss several attempts to characterize these QSS and explain why their prediction is difficult in general.

Ulf Lindstrom, Martin Rocek, Rikard von Unge

We show that supertwistor spaces constructed as a Kahler quotient of a hyperkahler cone (HKC) with equal numbers of bosonic and fermionic coordinates are Ricci-flat, and hence, Calabi-Yau. We study deformations of the supertwistor space induced from deformations of the HKC. We also discuss general infinitesimal deformations that preserve Ricci-flatness.

C. Wetterich

Chiral antisymmetric tensor fields can have chiral couplings to quarks and leptons. Their kinetic terms do not mix different representations of the Lorentz symmetry and a local mass term is forbidden by symmetry. The chiral couplings to the fermions are asymptotically free, opening interesting perspectives for a possible solution to the gauge hierarchy probl

Sanjay K. Ghosh, Tamal K. Mukherjee, Sibaji Raha

A thermodynamically consistent density dependent quark mass model has been used to study the velocity of sound in a hot quark-gluon plasma. The results are compared with the recent lattice data.

Jose F. Nieves, Palash B. Pal

We study the decay process of the Z boson to a photon and a graviton. The most general form of the on-shell amplitude, subject to the constraints due to the conservation of the electromagnetic and the energy-momentum tensor, is determined. The amplitude is expressed in terms of three form factors, two of which are CP-odd while one is CP-even. The latter, whi

O. Bertolami, J. G. Rosa, C. M. L. de Aragão, P. Castorina

We consider Noncommutative Quantum Mechanics with phase space noncommutativity. In particular, we show that a scaling of variables leaves the noncommutative algebra invariant, so that only the self-consistent effective parameters of the model are physically relevant. We also discuss the recently proposed relation of direct proportionality between the noncomm

V. A. Batarin, J. Butler, A. M. Davidenko, A. A. Derevschikov

A highly stable monitoring system based on blue and red light emitting diodes coupled to a distribution network comprised of optical fibers has been developed for an electromagnetic calorimeter that uses lead tungstate crystals readout with photomultiplier tubes. We report of the system prototype design and on the results of laboratory tests. Stability bette

V. V. Skokov, V. D. Toneev

In connection with the claim made at the Quark Matter 2005 Conference that the Brown-Rho scaling is ruled out by NA60 data we consider dimuon production from semi-central In+In collisions in a full dynamical model. It is shown that if only a modification of the density-dependent $ρ$-mass is allowed, the maximum of dimuon invariant mass spectra is only slight

Su-Chan Park

Using the Monte Carlo simulation method for bosonic reaction-diffusion systems introduced recently [S.-C. Park, Phys. Rev. E {\bf 72}, 036111 (2005)], one dimensional bosonic models are studied and compared to the corresponding Langevin equations derived from the coherent state path integral formalism. For the single species annihilation model, the exact asy

Ziemowit Popowicz

The extended N=2 supersymmetric Camasa - Holm equation is presented. It is accomplishe by formulation the supersymmeytric version of the Fuchssteiner method. In this framework we use two supersymmetric recursion operators of the N=2, $α=-2,4$ Korteweg - de Vries equation and constructed two different version of the supersymmetric Camassa - Holm equation. The

Y. M. Zhao, A. Arima

In this paper we obtain number of states with a given spin $I$ and a given isospin $T$ for systems with three and four nucleons in a single-$j$ orbit, by using sum rules of six-$j$ and nine-$j$ symbols obtained in earlier works.

François Martin, Emmanuel Royer

We give the algebra of quasimodular forms a collection of Rankin-Cohen operators. These operators extend those defined by Cohen on modular forms and, as for modular forms, the first of them provide a Lie structure on quasimodular forms. They also satisfy a ``Leibniz rule&#39;&#39; for the usual derivation. Rankin-Cohen operators are useful for proving arithm

Lianyi He, Meng Jin, Pengfei Zhuang

A general analysis of Meissner effect and spin susceptibility of a uniform superconductor in an asymmetric two-component fermion system is presented in nonrelativistic field theory approach. We found that, the pairing mechanism dominates the magnetization property of superconductivity, and the asymmetry enhances the paramagnetism of the system. At the turnin

Takuji Tsujimoto

Unusual elemental abundance patterns observed for stars belonging to nearby dwarf spheroidal (dSph) galaxies are discussed. Analysis of the [alpha/H] vs. [Fe/H] diagrams where alpha represents Mg or average of alpha-elements reveals that Fe from Type Ia supernovae (SNe Ia) does not contribute to the stellar abundances in the dSph galaxies where the member st

Matthias Burkardt

Generalized parton distributions can be used to obtain information about the dependence of parton distributions on the impact parameter. Potential consequences for T-odd single-spin asymmetries are discussed.

Bing Wang, Huanwen Tang, Chonghui Guo, Zhilong Xiu

Network&#39;s resilience to the malfunction of its components has been of great concern. The goal of this work is to determine the network design guidelines, which maximizes the network efficiency while keeping the cost of the network (that is the average connectivity) constant. With a global optimization method, memory tabu search (MTS), we get the optimal

Jiun-Cheng Chen, Hsian-Hua Tseng

We prove a numerical characterization of $\mathbb{P}^n$ for varieties with at worst isolated local complete intersection quotient singularities. In dimension three, we prove such a numerical characterization of $\mathbb{P}^3$ for normal $\mathbb{Q}$-Gorenstein projective varieties.

Hélène Perrin, Yves Colombe, Brigitte Mercier, Vincent Lorent

We present experimental results and theoretical analysis of the diffuse reflection of a Bose-Einstein condensate from a rough mirror. The mirror is produced by a blue-detuned evanescent wave supported by a dielectric substrate. The results are carefully analysed via a comparison with a numerical simulation. The scattering is clearly anisotropic, more pronoun

A. A. Methot

There are many different definitions of what a Bell-Kochen-Specker proof with POVMs might be. Here we present and discuss the minimal proof on qubits for three of these definitions and show that they are indeed minimal.

R. Andrews, A. T. Joseph, E. R. Pike, Sarben Sarkar

In this paper we describe theoretically quantum control of temporal correlations of entangled photons produced by collinear type II spontaneous parametric down-conversion. We examine the effect of spectral phase modulation of the signal or idler photons arriving at a 50/50 beam splitter on the temporal shape of the entangled-photon wave packet . The coincide

X. -L. Deng, D. Porras, J. I. Cirac

A system of trapped ions under the action of off--resonant standing--waves can be used to simulate a variety of quantum spin models. In this work, we describe theoretically quantum phases that can be observed in the simplest realization of this idea: quantum Ising and XY models. Our numerical calculations with the Density Matrix Renormalization Group method

GianCarlo Ghirardi, Luca Marinatto

We review two general criteria for deciding whether a pure bipartite quantum state describing a system of two identical particles is entangled or not. The first one considers the possibility of attributing a complete set of objective properties to each particle belonging to the composed system, while the second is based both on the consideration of the Slate

GianCarlo Ghirardi, Luca Marinatto

We prove that every conceivable hidden variable model reproducing the quantum mechanical predictions of almost any entangled state must necessarily violate Bell&#39;s locality condition. The proof does not involve the consideration of any Bell inequality but it rests on simple set theoretic arguments and it works for almost any noncompletely factorizable sta

M. S. Leifer

In the past few years it has been shown that universal quantum computation can be obtained by projective measurements alone, with no need for unitary gates. This suggests that the underlying logic of quantum computing may be an algebra of sequences of quantum measurements rather than an algebra of products of unitary operators. Such a Sequential Quantum Logi

Chi-Yee Cheung

The no-go theorem of unconditionally secure quantum bit commitment depends crucially on the assumption that Alice knows in detail all the probability distributions generated by Bob. We show that if a protocol is concealing, then the cheating unitary transformation is independent of any parameters (including probability distributions) secretly chosen by Bob,

Qing-yu Cai

The crucial issue of quantum communication protocol is its security. In this paper, we show that all the deterministic and direct two-way quantum communication protocols, sometimes called ping-pong (PP) protocols, are insecure when an eavesdropper uses the invisible photon to eavesdrop on the communication. With our invisible photon eavesdropping (IPE) schem

Nils Andersson, G. L. Comer

We develop a flux-conservative formalism for a Newtonian multi-fluid system, including dissipation and entrainment (i.e. allowing the momentum of one fluid to be a linear combination of the velocities of all fluids). Maximum use is made of mass, energy, and linear and angular momentum conservation to specify the equations of motion. Also used extensively are

L. Casillas, F. J. Espinosa, R. Huerta-Quintanilla, M. Rodriguez-Achach

We present a linear agent based model on brand competition. Each agent belongs to one of the two brands and interacts with its nearest neighbors. In the process the agent can decide to change to the other brand if the move is beneficial. The numerical simulations show that the systems always condenses into a state when all agents belong to a single brand. We

Christopher J. Erickson, Brian Neyenhuis, Dallin S. Durfee

We have demonstrated a high temperature vapor cell for absorption spectroscopy on the Ca intercombination line. The cell uses a dual chamber design to achieve the high temperatures necessary for an optically dense vapor while avoiding the necessity of high temperature vacuum valves and glass-to-metal seals. We have observed over 50 percent absorption in a si

M. Lazar, R. Schlickeiser

A rigorous and most general covariant kinetic formalism is developed to study the nonlinear waves interaction in relativistic Vlasov plasmas. The typical nonlinear plasma reaction is a nonlinear current measured by the nonlinear plasma conductivity, and these quantities are derived here on the basis of relativistic Vlasov-Maxwell equations. Knowing the nonli

Edoardo Milotti

Many simulations of stochastic processes require colored noises: I describe here an exact numerical method to simulate power-law noises: the method can be extended to more general colored noises, and is exact for all time steps, even when they are unevenly spaced (as may often happen for astronomical data, see e.g. N. R. Lomb, Astrophys. Space Sci. {\bf 39},

G. Maero, P. Quarati, F. Ferro

An interest for the low-energy range of the nonextensive distribution function arises from the study of radiative recombination in electron cooling devices in particle accelerators, whose experimentally measured reaction rates are much above the theoretical prediction. The use of generalized distributions, that differ from the Maxwellian in the low energy pa

Gabor Papp, Szilard Pafka, Maciej A. Nowak, Imre Kondor

We study empirical covariance matrices in finance. Due to the limited amount of available input information, these objects incorporate a huge amount of noise, so their naive use in optimization procedures, such as portfolio selection, may be misleading. In this paper we investigate a recently introduced filtering procedure, and demonstrate the applicability

Andrei P. Kirilyuk

Universal and rigorously derived concept of dynamic complexit (physics/9806002) shows that any system of interacting components, including society and civilisation, exists only as a process of highly inhomogeneous, qualitative development of its complexity. Modern state of civilisation corresponds to the end of unfolding of a big enough level of complexity.

Pekka Alitalo, Stanislav Maslovski, Sergei Tretyakov

We experimentally demonstrate a prototype of a cylindrical enlarging lens capable of enhancing and restoring evanescent fields. The enabling phenomenon is the resonant excitation of coupled surface modes in a system of two cylindrical arrays of small resonant particles. As was shown in [J. Appl. Phys. 96, 1293 (2004)], this phenomenon in planar arrays can be

V. S. Timoteo, C. L. Lima

We review the implementation of a q-deformed fermionic algebra in the Nambu--Jona-Lasinio model (NJL). The gap equations obtained from a deformed condensate as well as from the deformation of the NJL Hamiltonian are discussed. The effect of both temperature and deformation in the chiral symmetry restoration process as well as in the pion properties is studie

B. B. Back, PHOBOS Collaboration

The charged-particle pseudorapidity density for Au+Au collisions at sqrt(s_NN)=62.4 GeV has been measured over a wide range of impact parameters and compared to results obtained at other energies. As a function of collision energy, the pseudorapidity distribution grows systematically both in height and width. The mid-rapidity density is found to grow approxi

A. Jachens, J. Schumacher, B. Eckhardt, K. Knobloch

We investigate spatial and temporal cross-correlations between streamwise and normal velocity components in three shear flows: a low-dimensional model for vortex-streak interactions, direct numerical simulations for a nearly homogeneous shear flow and experimental data for a turbulent boundary layer. A driving of streamwise streaks by streamwise vortices giv

G. Cristadoro

Dynamical zeta functions provide a powerful method to analyze low dimensional dynamical systems when the underlying symbolic dynamics is under control. On the other hand even simple one dimensional maps can show an intricate structure of the grammar rules that may lead to a non smooth dependence of global observable on parameters changes. A paradigmatic exam

Oliver Robertshaw, Paul Tod

We consider two problems arising in the study of the Schrödinger-Newton equations. The first is to find their Lie point symmetries. The second, as an application of the first, is to investigate an approximate solution corresponding to widely separated lumps of probability. The lumps are found to move like point particles under a mutual inverse-square law of

F. Caravenna, G. Giacomin, M. Gubinelli

We consider a model of a random copolymer at a selective interface which undergoes a localization/delocalization transition. In spite of the several rigorous results available for this model, the theoretical characterization of the phase transition has remained elusive and there is still no agreement about several important issues, for example the behavior o

Péter Lévay

The differential geometric aspects of Geometric Phases are reviewed.

Ralph L. Cohen, Paul Norbury

In this paper we define and study the moduli space of metric-graph-flows in a manifold M. This is a space of smooth maps from a finite graph to M, which, when restricted to each edge, is a gradient flow line of a smooth (and generically Morse) function on M. Using the model of Gromov-Witten theory, with this moduli space replacing the space of stable holomor

Hua Bai

Chekhov, Fock and Kashaev introduced a quantization of the Teichmüller space $\mathcal{T}^q(S)$ of a punctured surface $S$, and an exponential version of this construction was developed by Bonahon and Liu. The construction of the quantum Teichmüller space crucially depends on certain coordinate change isomorphisms between the Chekhov-Fock algebras associated

G. M. Kudryavtseva, G. Y. Tsyaputa

The structure of the automorphism group of the sandwich semigroup IS_n is described in terms of standard group constructions.

Frank Leitenberger

We use the theory of the quantum group $U_q(gl(2,\RR))$ in order to develop a quantum theory of invariants and show a decomposition of invariants into a Gordan-Capelli series. Higher binary forms are introduced on the basis of braided algebras. We define quantised invariants and give basic examples. We show that the symbolic method of Clebsch and Gordan work

Frank Leitenberger

We classify all SL(2,R)-covariant Poisson structures on the Lobachevsky plane with respect to all multiplicative Poisson structures on SL(2,R) and describe Quantisations for all these Poisson structures.

Frank Leitenberger

Quantum deformations of sets of points of the real and the complexified projective line are constructed. These deformations depend on the deformation parameter q and certain further parameters λ_{ij}. The deformations for which the subspace of polynomials of degree three has a basis of ordered monomials are selected. We show that the corresponding algebras o

Frank Leitenberger

We define noncommutative binary forms. Using the typical representation of Hermite we prove the fundamental theorem of algebra and we derive a noncommutative Cardano formula for cubic forms. We define quantized elliptic and hyperelliptic differentials of the first kind. Following Abel we prove Abel&#39;s Theorem.

Frank Leitenberger

By a transfer principle Pascal&#39;s Theorem is equivalent to a theorem about point pairs on the real line. It appears that Pascal&#39;s Theorem is equivalent to the vanishing of a common invariant of six quadratic forms. Using the q-deformed invariant theory of \cite{L} we construct corresponding quantum invariants by a computer calculation.

Charles Cadman

We use twisted stable maps to answer the following question. Let E\subset P^2 be a smooth cubic. How many rational degree d curves pass through a general points of E, have b specified tangencies with E and c unspecified tangencies, and pass through 3d-1-a-2b-c general points of P^2? The answer is given as a generalization of Kontsevich&#39;s recursion. We al

Christian Rosendal

A topological group G is defined to have property (OB) if any G-action by isometries on a metric space, which is separately continuous, has bounded orbits. We study this topological analogue of the socalled Bergman property in the context of Polish groups, where we show it to have several interesting reformulations and consequences. We subsequently apply the

Marco Abate, Filippo Bracci, Francesca Tovena

Let $M$ be a complex manifold and $S\subset M$ a (possibly singular) subvariety of $M$. Let $f\colon M\to M$ be a holomorphic map such that $f$ restricted to $S$ is the identity. We show that one can associate to $f$ a holomorphic section $X_f$ of a sheaf related to the embedding of $S$ in $M$ and that such a section reads the dynamical behavior of $f$ along

Sergey A. Denisov, Alexander Kiselev

We review recent advances in the spectral theory of Schrödinger operators with decaying potentials. The area has seen spectacular progress in the past few years, stimulated by several conjectures stated by Barry Simon starting at the 1994 International Congress on Mathematical Physics in Paris. The one-dimensional picture is now fairly complete, and provides

Lam Raga A. Markely, David Andrzejewski, Erick Butzlaff, Alexander Kiselev

We study analytically and numerically a model describing front propagation of a KPP reaction in a fluid flow. The model consists of coupled one-dimensional reaction-diffusion equations with different drift coefficients. The main rigorous results give lower bounds for the speed of propagation that are linear in the drift coefficient, which agrees very well wi

John Armstrong

The extension of the knot group $π_1(S^3\setminus K)$ to the category of tangles is introduced via a new category-theoretic construction. Through this presentation, a new avenue of proof for results about knot groups is opened.

P. Constantin, A. Kiselev, L. Ryzhik, A. Zlatos

We study enhancement of diffusive mixing on a compact Riemannian manifold by a fast incompressible flow. Our main result is a sharp description of the class of flows that make the deviation of the solution from its average arbitrarily small in an arbitrarily short time, provided that the flow amplitude is large enough. The necessary and sufficient condition

Ferit Ozturk, Klaus Niederkrüger

We show that Brieskorn manifolds with their standard contact structures are contact branched coverings of spheres. This covering maps a contact open book decomposition of the Brieskorn manifold onto a Milnor open book of the sphere.

Giambattista Marini

Let C be a complex curve of genus g, let J(C) be its Jacobian and let R(C) be its tautological ring, that is, the group of algebraic cycles modulo algebraic equivalence. We study the algebraic structure of R(C). In particular, we give a detailed description of all the possibilities that may occur for g<9: we construct convenient basis and we determine the ma

Ehud Hrushovski, Ya&#39;acov Peterzil

We use a new construction of an o-minimal structure, due to Lipshitz and Robinson, to answer a question of van den Dries regarding the relationship between arbitrary o-minimal expansions of real closed fields and structures over the real numbers. We write a first order sentence which is true in the Lipshitz-Robinson structure but fails in any possible interp

Paolo Piccione, Daniel V. Tausk

Symmetric connections that are compatible with semi-Riemannian metrics can be characterized using an existence result for an integral leaf of a (possibly non integrable) distribution. In this paper we give necessary and sufficient conditions for a left-invariant connection on a Lie group to be the Levi-Civita connection of some semi-Riemannian metric on the

Michael Hellus

The number of equations needed to cut out a variety given by an ideal is called the arithmetic rank (of the ideal). It was shown in [8] that the notion of arithmetic rank is strongly related to the concept of regular sequences on the Matlis duals of certain local cohomology modules and thus is related to the set of associated primes of such Matlis duals. Whi

Hechun Zhang, R. B. Zhang

A string basis is constructed for each subalgebra of invariants of the function algebra on the quantum special linear group. By analyzing the string basis for a particular subalgebra of invariants, we obtain a ``canonical basis&#39;&#39; for every finite dimensional irreducible $U_q({\mathfrak{sl}}(n))$-module. It is also shown that the algebra of functions

V. O. Nikiforov, A. L. Fradkov, B. R. Andrievsky

The relative degree limitation for adaptive observer-based synchronization schemes is overcome. The scheme is extended to nonpassifiable systems. Two synchronization methods are described and justified based on augmented error adaptive observer and high-order tuners. The solution is based on modern theory of nonlinear adaptive control, particularly on nonlin

Alberto Abbondandolo, Pietro Majer

We give an alternative proof of the stable manifold theorem as an application of the (right and left) inverse mapping theorem on a space of sequences. We investigate the diffeomorphism class of the global stable manifold, a problem which in the general Banach setting gives rise to subtle questions about the possibility of extending germs of diffeomorphisms.

Bernd Sturmfels, Seth Sullivant

The construction of joins and secant varieties is studied in the combinatorial context of monomial ideals. For ideals generated by quadratic monomials, the generators of the secant ideals are obstructions to graph colorings, and this leads to a commutative algebra version of the Strong Perfect Graph Theorem. Given any projective variety and any term order, w

Peter Quast

We study families of submanifolds in symmetric spaces of compact type arising as exponential images of s-orbits of variable radii. Special attention is given to the cases where the s-orbits are symmetric.

Yakov Varshavsky

The goal of this paper is to give a simple proof of Deligne&#39;s conjecture (proven by Fujiwara) and to generalize it to the situation appearing in our joint project with David Kazhdan on the global Langlands correspondence over function fields. Our proof holds in the realm of ordinary algebraic geometry and does not use rigid geometry.

Richard Dipper, Stephen Doty, Jun Hu

In this paper we prove Schur-Weyl duality between the symplectic group and Brauer algebra over an arbitrary infinite field $K$. We show that the natural homomorphism from the Brauer algebra $B_n(-2m)$ to the endomorphism algebra of tensor space $(K^{2m})^{\otimes n}$ as a module over the symplectic similitude group $GSp_{2m}(K)$ (or equivalently, as a module

Yasushi Homma

We study geometric first order differential operators on quaternionic Kähler manifolds. Their principal symbols are related to the enveloping algebra and Casimir elements for $\Sp(1)\Sp(n)$. This observation leads to anti-symmetry of the principal symbols and Bochner-Weitzenböck formulas for operators. As an application, we estimate the first eigenvalues of

Christoph A. Stephan

In [7-9] and [10] the conjecture is presented that almost-commutative geometries, with respect to sensible physical constraints, allow only the standard model of particle physics and electro-strong models as Yang-Mills-Higgs theories. In this publication a counter example will be given. The corresponding almost-commutative geometry leads to a Yang-Mills-Higg

V. I. Ritus

Defined by Bogoliubov coefficients the spectra of pairs of Bose (Fermi) massless quanta, emitted by point mirror in 1+1-space, coincide up to multiplier $e^2/ \hbar c$ with the spectra of photons (scalar quanta), emitted by point electric (scalar) charge in 3+1-space for any common trajectory of the sources. The integral connection of the propagator of a pai

D. I. Kazakov, G. S. Vartanov

The structure of the UV divergencies in higher dimensional nonrenormalizable theories is analysed. Based on renormalization operation and renormalization group theory it is shown that even in this case the leading divergencies (asymptotics) are governed by the one-loop diagrams the number of which, however, is infinite. Explicit expression for the one-loop c

Forough Nasseri

In this Reply, using E.R. Bezerra de Mello&#39;s comment, I correct calculations and results presented in Phys. Lett. B 614 (2005) 140-142 about fine structure constant in the spacetime of a cosmic string.

Holger B. Nielsen, Masao Ninomiya

We seek here to unify the second law of thermodynamics with the other laws, or at least to put up a law behind the second law of thermodynamics. Assuming no fine tuning, concretely by a random Hamiltonian, we argue just from equations of motion -- but {\em without} second law -- that entropy cannot go first up and then down again except with the rather stric

Fiorenzo Bastianelli

We describe how to construct and compute unambiguously path integrals for particles moving in a curved space, and how these path integrals can be used to calculate Feynman graphs and effective actions for various quantum field theories with external gravity in the framework of the worldline formalism. In particular, we review a recent application of this wor

A. P. Balachandran, Kumar S. Gupta, S. Kurkcuoglu

Waves on ``commutative&#39;&#39; spacetimes like R^d are elements of the commutative algebra C^0(R^d) of functions on R^d. When C^0(R^d) is deformed to a noncommutative algebra {\cal A}_θ(R^d) with deformation parameter θ({\cal A}_0 (R^d) = C^0(R^d)), waves being its elements, are no longer complex-valued functions on R^d. Rules for their interpretation, suc

Y. H. Yuan

The meson spectroscopy is studied in the framework of the QCD string model. The mesons are composed of spinless quarks which move relativistically. We show that the QCD string model reproduces the straight line Regge trajectories and exibit the correct string slopes for both light-light and heavy-light mesons. We also present the exact numerical solution and

J. Lowe, M. D. Scadron

We use recent data on K^+ -> pi^+ e^+ e^-, together with known values for the pion form factor, to derive experimental values for the kaon electromagnetic form factor for 0 < q^2 < 0.125 (GeV/c)^2. The results are then compared with the predictions of the Vector Meson Dominance model, which gives a good fit to the experimental results.

John Ellis, Dimitri Nanopoulos, Keith A. Olive, Yudi Santoso

We estimate the mass of the lightest neutral Higgs boson h in the minimal supersymmetric extension of the Standard Model with universal soft supersymmetry-breaking masses (CMSSM), subject to the available accelerator and astrophysical constraints. For m_t = 174.3 GeV, we find that 114 GeV < m_h < 127 GeV and a peak in the tan beta distribution simeq 55. We o

M. Kirch, A. Manashov, A. Schafer

The extension of the method [arXiv:hep-ph/0503109] for solving the leading order evolution equation for Generalized Parton Distributions (GPDs) is presented. We obtain the solution of the evolution equation both for the flavor nonsinglet quark GPD and singlet quark and gluon GPDs. The properties of the solution and, in particular, the asymptotic form of GPDs

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

We study static magnetic monopoles in the context of varying alpha theories and show that there is a group of models for which the t&#39;Hooft-Polyakov solution is still valid. Nevertheless, in general static magnetic monopole solutions in varying alpha theories depart from the classical t&#39;Hooft-Polyakov solution with the electromagnetic energy concentra

Jacques Soffer

We propose a novel mechanism for exclusive diffractive Higgs production $pp \to Hpp$, in which the Higgs carries a significant fraction of the projectile proton&#39;s momentum. This mechanism will then provide a clear experimental signal for Higgs production, due to the small background in this kinematic region. The key assumption underlying our analysis is

Z. Xu, C. Greiner

Employing a newly developed pQCD inspired parton cascade we simulate the space time evolution of gluons which are produced initially in a heavy ion collision at RHIC energy. The inelastic $gg \leftrightarrow ggg$ interactions are for the first time implemented obeying full detailed balance. The numerical results show that thermalization of gluons is mainly d

Yu. A. Tarasov, S. L. Fokin

We investigate the suppression of $π^0$-spectrum in a wide range of $p_\perp$ up 60 GeV/c which is caused by the energy loss of the gluon and quark jets in quark-gluon plasma. The physical characteristics of initial and mixed phases were found in the effective quasiparticle model by analogy with previous work \cite{5}. The PHENIX data up 10 GeV/c within the

Seungwon Baek, F. J. Botella, David London, Joao P. Silva

If new physics (NP) is present in B -> pi pi decays, it can affect the isospin I=2 or I=0 channels. In this paper, we discuss various methods for detecting and measuring this NP. The techniques have increasing amounts of theoretical hadronic input. If NP is eventually detected in B -> pi pi -- there is no evidence for it at present -- one will be able to dis

O. V. Utyuzh, G. Wilk, Z. Wlodarczyk

We describe an attempt to model numerically Bose-Einstein correlations (BEC) from &#34;within&#34;, i.e., by using them as the most fundamental ingredient of some Monte Carlo event generator (MC) rather than considering them as a kind of (more or less important, depending on the actual situation) &#34;afterburner&#34;, which inevitably changes original physi

Masayasu Harada

In this write-up, I summarize the key ingredients of the vector manifestaion formulated in the hidden local symmetry theory, in which the $ρ$ meson becomes massless degenerated with the pion at the chiral phase transition point.

S. N. Yang, S. S. Kamalov

The Dubna-Mainz-Taipei (DMT) dynamical model for pion electromagnetic production, which describe well the existing data from threshold up to 1 GeV photon lab energy is presented and used to analyze recent data in the $Δ$ region . We find that within DMT model, the bare $Δ$ is almost spherical while the physical $Δ$ is oblate. The deformation is almost satura