January 2003 arXiv papers — page 5

J. Lukasik, G. Auger, M. L. Begemann-Blaich, N. Bellaize

Invariant cross sections of intermediate mass fragments in peripheral collisions of Au on Au at incident energies between 40 and 150 AMeV have been measured with the 4-pi multi-detector INDRA. The maximum of the fragment production is located near mid-rapidity at the lower energies and moves gradually towards the projectile and target rapidities as the energ

B. B. Back, PHOBOS Collaboration

The PHOBOS experiment at RHIC has measured the total multiplicity of primary charged particles as a function of collision centrality in Au+Au collisions at sqrt(s_NN) = 19.6, 130 and 200 GeV. Above sqrt(s_NN) ~ 20 GeV, the total multiplicity per participating nucleon pair (<N_ch>/<N_part/2>) in central events scales with sqrt(s) in the same way as <N_ch> in

Ugurhan Mugan, Fahd Jrad

Starting from the second Painlevé equation, we obtain Painlevé type equations of higher order by using the singular point analysis.

L. Biferale, G. Boffetta, A. Celani, A. Lanotte

We present the results of a numerical investigation of three-dimensional decaying turbulence with statistically homogeneous and anisotropic initial conditions. We show that at large times, in the inertial range of scales: (i) isotropic velocity fluctuations decay self-similarly at an algebraic rate which can be obtained by dimensional arguments; (ii) the rat

D. Hennig, J. F. R. Archilla, J. Agarwal

We study a model for polaron-like charge transport mechanism along DNA molecules with emphasis on the impact of parametrical and structural disorder. Our model Hamiltonian takes into account the coupling of the charge carrier to two different kind of modes representing fluctuating twist motions of the base pairs and H-bond distortions within the double helix

Christian Ferrari, Hynek Kovarik

We study the time decay of magnetic Stark resonant states. As our main result we prove that for sufficiently large time these states decay exponentially with the rate given by the imaginary parts of eigenvalues of certain non-selfadjoint operator. The proof is based on the method of complex translations.

Wendell Culp-Ressler

We present a theory of reduction of binary quadratic forms with coefficients in Z[lambda], where lambda is the minimal translation in a Hecke group. We generalize from the modular group Gamma(1) = SL(2,Z) to the Hecke groups and make extensive use of modified negative continued fractions.

Florentin Smarandache

Thirty-three new definitions are presented, derived from neutrosophic set, neutrosophic probability, neutrosophic statistics, and neutrosophic logic. Each one is independent, short, with references and cross references like in a dictionary style.

Imre Barany, Krystyna Kuperberg, Tudor Zamfirescu

This paper gives a partial confirmation of a conjecture of P. Agarwal, S. Har-Peled, M. Sharir, and K. Varadarajan that the total curvature of a shortest path on the boundary of a convex polyhedron in the 3-dimensional Euclidean space cannot be arbitrarily large. It is shown here that the conjecture holds for a class of polytopes for which the ratio of the r

Justin R. Peters, Ryan J. Zerr

We obtain a characterization in terms of dynamical systems of those r-discrete groupoids for which the groupoid C*-algebra is approximately finite-dimensional (AF). These ideas are then used to compute the K-theory for AF algebras by utilizing the actions of these partial homeomorphisms, and these K-theoretic calculations are applied to some specific example

Mohammed Ridha Alaimia, Justin R. Peters

We study the semicrossed product of a finite dimensional C^*-algebra by two types of commuting automorphisms, and identify them with matrix algebras of analytic functions in two variables. We look at the connections with semicrossed products by Z_+ actions.

Antonio Loria, Elena Panteley, Dobrivoje Popovic, Andrew R. Teel

In previous papers we have introduced a sufficient condition for uniform attractivity of the origin for a class of nonlinear time-varying systems which is stated in terms of persistency of excitation (PE), a concept well known in the adaptive control and systems identification literature. The novelty of our condition, called uniform delta-PE, is that it is t

Artur Nicolau, Joaquim Ortega-Cerdà, Kristian Seip

We prove that a suitably adjusted version of Peter Jones&#39; formula for interpolation by bounded holomorphic functions gives a sharp upper bound for what is known as the constant of interpolation. We show how this leads to precise and computable numerical bounds for this constant.

Jasper V. Stokman

Eigenfunctions of the Askey-Wilson second order $q$-difference operator for $0<q<1$ and $|q|=1$ are constructed as formal matrix coefficients of the principal series representation of the quantized universal enveloping algebra $U_q(sl(2,\mathbb{C}))$. The eigenfunctions are in integral form and may be viewed as analogues of Euler&#39;s integral representatio

Wolf Barth, Alessandra Sarti

A K3-surface is a (smooth) surface which is simply connected and has trivial canonical bundle. In these notes we investigate three particular pencils of K3-surfaces with maximal Picard number. More precisely the general member in each pencil has Picard number 19 and each pencil contains four surfaces with Picard number 20. These surfaces are obtained as the

Jose L. Rodriguez, Dirk Scevenels

Quillen's plus construction is a topological construction that kills the maximal perfect subgroup of the fundamental group of a space without changing the integral homology of the space. In this paper we show that there is a topological construction that, while leaving the integral homology of a space unaltered, kills even the intersection of the transfinite

David Bessis

We give a detailed account of the classical Van Kampen method for computing presentations of fundamental groups of complements of complex algebraic curves, and of a variant of this method, working with arbitrary projections (even with vertical asymptotes).

Thomas Neukirchner

We present an approach to solvable pseudo-Riemannian symmetric spaces based on papers of M.Cahen, M.Parker and N.Wallach. Thereby we reproduce the classification of solvable symmetric triples of Lorentzian signature $(1,n-1)$ and complete the case of signature $(2,n-2)$. Moreover we discuss the topology of non-simply-connected symmetric spaces.

Edward Givelberg, Julian Bunn

The human cochlea is a remarkable device, able to discern extremely small amplitude sound pressure waves, and discriminate between very close frequencies. Simulation of the cochlea is computationally challenging due to its complex geometry, intricate construction and small physical size. We have developed, and are continuing to refine, a detailed three-dimen

Jae-Wook Chung, Xiao-Song Lin

Given a diagram $D$ of a knot $K$, we consider the number $c(D)$ of crossings and the number $b(D)$ of overpasses of $D$. We show that, if $D$ is a diagram of a nontrivial knot $K$ whose number $c(D)$ of crossings is minimal, then $1+\sqrt{1+c(D)} \leq b(D)\leq c(D)$. These inequalities are shape in the sense that the upper bound of $b(D)$ is achieved by alt

K. G. Selivanov, A. V. Smilga

We construct low energy effective Lagrangians for 3d N=4 supersymmetric Yang-Mills theory with any gauge group. They represent supersymmetric sigma models at hyper-Kahlerian manifolds of dimension 4r (r is the rang of the group). In the asymptotic region, perturbatively exact explicit expression for the metric are written. We establish the relationship of th

Stefan Fredenhagen

We show how a large class of boundary RG flows in two-dimensional conformal field theories can be summarized in a single rule. This rule is a generalization of the &#39;absorption of the boundary spin&#39;-principle of Affleck and Ludwig and applies to all theories which have a description as a coset model. We give a formulation for coset models with arbitra

R. Mansouri, M. Borhani, S. Khakshournia

We consider a spherical thick 3-brane immersed in a five-dimensional bulk spacetime. We demonstrate how the thick brane equation of motion expanded in powers of the thickness of the brane can be obtained from the expected junction conditions on the boundaries of thick brane with the two embedding spacetimes. It is shown that the finite thickness leads to a f

Stefano Bellucci

We consider a two-dimensional non-commutative inverted oscillator in the presence of a constant magnetic field, coupled to the system in a ``symplectic&#39;&#39; and ``Poisson&#39;&#39; way. We show that it has a discrete energy spectrum for some value of the magnetic field.

H. Belich, M. M. Ferreira, J. A. Helayël-Neto, M. T. D. Orlando

We take as starting point the planar model arising from the dimensional reduction of the Maxwell Electrodynamics with the (Lorentz-violating) Carroll-Field-Jackiw term. We then write and study the extended Maxwell equations and the corresponding wave equations for the potentials. The solution to these equations show some interesting deviations from the usual

J. Antonio Garcia, Alberto Guijosa, J. David Vergara

We examine the extent to which the action for the membrane of M-theory (the eleven-dimensional construct which underlies and unifies all of the known string theories) simplifies in the so-called Open Membrane (OM) limit, a limit which lies at the root of the various manifestations of noncommutativity in the string context. In order for the discussion to be r

Sheldon Lee Glashow

Mixing between light and heavy neutrino states has been proposed as an explanation (or partial explanation) for the 3-sigma NuTeV anomaly and the 2-sigma departure of the $Z^0$ invisible width from its expected value. I assume herein that neutrino masses and mixings result from the conventional seesaw mechanism involving six chiral neutrino states, the first

R. Micha, I. Tkachev

After a short review of inlationary preheating, we discuss the development of equilibrium in the frameworks of massless $λΦ^4$ model. It is shown that the process is characterised by the appearance of Kolmogorov spectra and the evolution towards thermal equilibrium follows self-similar dynamics. Simplified kinetic theory gives values for all characteristic e

A. B. Kaidalov

Predictions of the nonperturbative Quark Gluon Strings model based on the 1/N-expansion in QCD and string picture of interactions for production of states containing heavy quarks are considered. Relations between fragmentation functions for different states are used to predict the fragmentation function of c-quark to J/psi-mesons. The resulting cross section

R. Rapp, E. V. Shuryak

Nonperturbative effects in $D$-meson production in pion-nucleon and proton-nucleon collisions are investigated within the recombination model. The coalescence of perturbatively created charm quarks with sea- and valence-quarks from projectile and target fragments is shown to be competitive in magnitude with standard fragmentation calculations at both central

George Sterman

Infrared safe differential cross sections, such as event shape distributions, can be measured over wide kinematic ranges, from regions where fixed order calculations are adequate to regions where nonperturbative dynamics dominate. Such observables provide an ideal laboratory for the study of the transition between weak and strong coupling in quantum field th

ST Tsou

It is shown that all existing data on mixing between up and down fermion states (i.e. CKM matrix and neutrino oscillations) and on the hierarchical quark and lepton mass ratios between generations are consistent with the two phenomena being both consequences of a mass matrix rotating in generation space with changing energy scale. As a result, the rotation o

A. Denner, M. Melles, S. Pozzorini

We present results on the two-loop leading and angular-dependent next-to-leading logarithmic virtual corrections to arbitrary processes at energies above the electroweak scale. In the `t Hooft-Feynman gauge the relevant Feynman diagrams involving soft and collinear gauge bosons γ, Z, W^\pm coupling to external legs are evaluated in the eikonal approximation

Andrew Chamblin, Fred Cooper, Gouranga C. Nayak

If the fundamental Planck scale is near a TeV, then parton collisions with high enough center-of-mass energy should produce black holes. The production rate for such black holes has been extensively studied for the case of a proton-proton collision at \sqrt s = 14 TeV and for a lead-lead collision at \sqrt s = 5.5 TeV at LHC. As the parton energy density is

A. A. Arkhipov

It has been shown that the great ancient Pythagorean ideas have found themselves in the latest researches in high energy elementary particles and nuclear physics. In this respect we concern and discuss the mathematical, physical and geometrical aspects of the famous Froissart theorem and in this way one establishes a link of this theorem to the mathematics a

Yusuf Dincer

In this paper, I study the branching ratio of the rare radiative decay $B_s \to ν\barν γ$ in the framework of the Fourth-Generation Standard Model and the Two-Higgs-Doublet Model. It is shown that this quantity is a very effective tool for establishing new physics beyond the Standard Model. It is observed that there is a region in the parameter space in both

Simon Catterall

It is known that certain theories with extended supersymmetry can be discretized in such a way as to preserve an exact fermionic symmetry. In the simplest model of this kind, we show that this residual supersymmetric invariance is actually a BRST symmetry associated with gauge fixing an underlying local shift symmetry. Furthermore, the starting lattice actio

A. Bodek, U. K. Yang

We use new scaling variables $x_w$ and $ξ_w$, and add low $Q^2$ modifications to GRV94 and GRV98 leading order parton distribution functions such that they can be used to model electron, muon and neutrino inelastic scattering cross sections (and also photoproduction) at both very low and high energie.

Michael Edmund Tobar, John Gideon Hartnett

A new experiment to test for the time independence of the fine structure constant, alpha, is proposed. The experiment utilizes orthogonally polarized Transverse Electric and Transverse Magnetic Whispering Gallery Modes in a single sapphire resonator tuned to similar frequencies. When configured as a dual mode sapphire clock, we show that the anisotropy of sa

K. Keahey, T. Fredian, Q. Peng, D. P. Schissel

The National Fusion Collaboratory (NFC) project was created to advance scientific understanding and innovation in magnetic fusion research by enabling more efficient use of existing experimental facilities through more effective integration of experiment, theory, and modeling. To achieve this objective, NFC introduced the concept of &#34;network services&#34

Oleg Kiselyov

This paper considers an example of Object-Oriented Programming (OOP) leading to subtle errors that break separation of interface and implementations. A comprehensive principle that guards against such errors is undecidable. The paper introduces a set of mechanically verifiable rules that prevent these insidious problems. Although the rules seem restrictive,

K. Keahey, V. Welch

In this document we describe our work-in-progress for enabling fine-grain authorization of resource management. In particular, we address the needs of Virtual Organizations (VOs) to enforce their own policies in addition to those of the resource owners.

Thomas Wolf

A method is presented that reduces the number of terms of systems of linear equations (algebraic, ordinary and partial differential equations). As a byproduct these systems have a tendency to become partially decoupled and are more likely to be factorizable or integrable. A variation of this method is applicable to non-linear systems. Modifications to improv

Thomas Wolf

A new integration technique is presented for systems of linear partial differential equations (PDEs) for which syzygies can be formulated that obey conservation laws. These syzygies come for free as a by-product of the differential Groebner Basis computation. Compared with the more obvious way of integrating a single equation and substituting the result in o

P. Blair Blakie, Robert J. Ballagh, Charles W. Clark

We demonstrate how a topological atom laser can be realized by output coupling a trapped vortex state with a Raman scattering process. We find a linearized analytic solution from which a generalized resonance condition for Raman output coupling is developed. Using numerical simulations of a two component Gross-Pitaevskii equation in two and three dimensions

P. L. Kuhns, M. J. R. Hoch, W. G. Moulton, A. P. Reyes J. Wu

59Co NMR measurements on La1-xSrxCoO3 reported here establish unequivocally, for the first time, the coexistence of ferromagnetic regions, spin glass regions, and hole poor low spin regions at all x values from 0.1 to 0.5. A zero external field NMR spectrum, which is assigned to the ferromagnetic regions, has a spectral shape which is nearly x independent at

S. Picoli, R. S. Mendes, L. C. Malacarne

In a comparative study, the q-exponential and Weibull distributions are employed to investigate frequency distributions of basketball baskets, cyclone victims, brand-name drugs by retail sales, and highway length. In order to analyze the intermediate cases, a distribution, the q-Weibull one, which interpolates the q-exponential and Weibull ones, is introduce

Mark A. Miller, Daan Frenkel

Using a combination of Monte Carlo techniques, we locate the liquid--vapor critical point of adhesive hard spheres. We find that the critical point lies deep inside the gel region of the phase diagram. The (reduced) critical temperature and density are $τ_c=0.1133\pm0.0005$ and $ρ_c=0.508\pm0.01$. We compare these results with the available theoretical predi

Todor M. Mishonov, Tihomir I. Valchev, Liliya A. Atanasova, Peter A. Ivanov

A methodical derivation of RKKY interaction in framework of T=0 Green function method is given in great detail. The article is complimentary to standard textbooks on the physics of magnetism and condensed matter physics. It is shown that the methods of statistical mechanics gives a standard and probably simplest derivation of the exchange interaction. A para

C. Gros, P. Lemmens, M. Vojta, R. Valenti

We present a comprehensive study of the coupled tetrahedra-compound Cu2Te2O5Br2 by theory and experiments in external magnetic fields. We report the observation of a longitudinal magnon in Raman scattering in the ordered state close to quantum criticality. We show that the excited tetrahedral-singlet sets the energy scale for the magnetic ordering temperatur

J. Quintanilla, K. Capelle, L. N. Oliveira

In recent photodoping experiments Decca et al. [PRL 85, 3708 (2000)] have observed an unusually long-ranged proximity effect between the superconducting and insulating phases of YBCO. Here we critically examine the claim in that reference that such long range is anomalous. We show that, once the novel nature of the experiments has been properly accounted for

M. Wouters, J. Tempere, J. T. Devreese

We present a model for sympathetic cooling of a mixture of fermionic and bosonic atomic gases in harmonic traps, based on a three-fluid description. The model confirms the experimentally observed cooling limit of about 0.2 T_F when only bosons are pumped. We propose sequential cooling -- first pumping of bosons and afterwards fermions -- as a way to obtain l

D. Sornette

This review is a partial synthesis of the book ``Why stock market crash&#39;&#39; (Princeton University Press, January 2003), which presents a general theory of financial crashes and of stock market instabilities that his co-workers and the author have developed over the past seven years. The study of the frequency distribution of drawdowns, or runs of succe

O. V. Dolgov, R. S. Gonnelli, G. A. Ummarino, A. A. Golubov

In the present work we calculate the tunneling density of states (DOS) of MgB% $_{2}$ for different tunneling directions by directly solving the two-band Eliashberg equations (EE) in the real-axis formulation. This procedure reveals the fine structures of the DOS due to the optical phonons. Then we show that the numeric inversion of the standard \emph{single

A. S. Alexandrov

Most of the proposed models of high-temperature superconductivity (HTSC) are based on the short-range electron-electron correlations or/and on a short-range electron-phonon interaction. However, in the cuprates the screening is poor due to a low carrier density, layered crystal structure, and high ionicity of the lattice. We develop further the bipolaron mod

M. Nazih, A. de Visser, L. Zhang, O. Tegus

We report thermal expansion measurements carried out on a single-crystal of the giant magnetocaloric effect material Gd5(Si0.43Ge0.57)4. At the magneto-structural phase transition at T_0 ~ 240 K, large steps in the relative length change DELTAL/L along the principle crystallographic axes are observed. The single-step behaviour in DELTAL/L indicates that the

You-Quan Li, Shi-Jian Gu, Zu-Jian Ying

In this paper we solve one dimensional SU(3) bosons with repulsive $δ$-function interaction by means of Bethe ansatz method. The features of ground state and low-lying excited states are studied by both numerical and analytic methods. We show that the ground state is a SU(3) color ferromagnetic state. The configurations of quantum numbers for the ground stat

M. H. Ghatee, A. Maleki, H. Ghaed-Sharaf

The recent empirical correlation for the surface tension is further investigated for universality. C5-C8 liquid hydrocarbons, for which accurate surface tension data over the complete liquid range are available, are used. Functional reduced surface entropy is derived, which is in the general form of Trouton&#39;s rule. It is characterized by the critical exp

A. Liebsch

The Mott insulator LaVO$_3$ is known to become metallic if La is replaced by small concentrations of Ca. Since surface quasi-particle spectra of various perovskites are more strongly correlated than their bulk spectra, the coexistence of a metallic bulk and an insulating surface layer might be feasible. To investigate this possibility the dynamical mean fiel

A. Liebsch

Quasi-particle spectra of the layer perovskite Sr$_2$RuO$_4$ are calculated within Dynamical Mean Field Theory for increasing values of the on-site Coulomb energy $U$. At small $U$ the planar geometry splits the $t_{2g}$ bands near $E_F$ into a wide, two-dimensional $d_{xy}$ band and two narrow, nearly one-dimensional $d_{xz,yz}$ bands. At larger $U$, howeve

Sergei V. Kalinin, Dawn A. Bonnell

Electric Scanning Probe Microscopies are used to characterize the surface behavior of ferroelectric materials. The effects of local charge density on the chemistry and physics of ferroelectric surfaces are investigated. The kinetics and thermodynamics parameters of adsorption are assessed by variable temperature Scanning Surface Potential Microscopy. Contras

P. Engels, I. Coddington, P. C. Haljan, V. Schweikhard

We study the formation of large vortex aggregates in a rapidly rotating dilute-gas Bose-Einstein condensate. When we remove atoms from the rotating condensate with a tightly focused, resonant laser, the density can be locally suppressed, while fast circulation of a ring-shaped superflow around the area of suppressed density is maintained. Thus a giant vortex

Alexander Unzicker, Karl Fabian

A circular twist disclination is a nontrivial example of a defect in an elastic continuum that causes large deformations. The minimal potential energy and the corresponding displacement field is calculated by solving the Euler-Lagrange-equations. The nonlinear incompressibility constraint is rigorously taken into account. By using an appropriate curvilinear

Patrik L. Ferrari, Herbert Spohn

A statistical mechanics model for a faceted crystal is the 3D Ising model at zero temperature. It is assumed that in one octant all sites are occupied by atoms, the remaining ones being empty. Allowed atom configurations are such that they can be obtained from the filled octant through successive removals of atoms with breaking of precisely three bonds. If V

Fred C. Adams, Greg Laughlin

This paper explores the intermediate-time dynamics of newly formed solar systems with a focus on possible mechanisms for planetary migration. We consider two limiting corners of the available parameter space -- crowded systems containing N=10 giant planets in the outer solar system, and solar systems with N=2 planets that are tidally interacting with a circu

Beverley J. Wills, Zhaohui Shang

The evolution of luminous QSOs is linked to the evolution of massive galaxies. We know this because the relic black-holes found locally have masses dependent on the properties of the host galaxy&#39;s bulge. An important way to explore this evolution would be to measure dependences of black hole masses and Eddington accretion ratios over a range of redshifts

Mark C. Neyrinck, Andrew J. S. Hamilton, Nickolay Y. Gnedin

By comparing the PSCz galaxy power spectrum with haloes from nested and phased N-body simulations, we try to understand how IRAS infrared-selected galaxies populate dark-matter haloes. We pay special attention to the way we identify haloes in the simulations.

Douglas P. Finkbeiner

A full-sky H-alpha map with 6 arcmin (FWHM) resolution is presented. This map is a composite of the Virginia Tech Spectral line Survey (VTSS) in the north and the Southern H-Alpha Sky Survey Atlas (SHASSA) in the south. The Wisconsin H-Alpha Mapper (WHAM) survey provides a stable zero-point over 3/4 of the sky on a 1 degree scale. This composite map can be u

K. Mukai, A. Kinkhabwala, J. R. Peterson, S. M. Kahn

We present Chandra HETG spectra of seven cataclysmic variables. We find that they divide unambiguously into two distinct types. Spectra of the first type are remarkably well fit by a simple cooling flow model, which assumes only steady-state isobaric radiative cooling. The maximum temperature and the normalization, which provides a highly precise measurement

Caroline E. J. M. L. J. Terquem

We calculate the linear torque exerted by a planet on a circular orbit on a disc containing a toroidal magnetic field. All fluid perturbations are singular at the so--called magnetic resonances, where the Doppler shifted frequency of the perturbation matches that of a slow MHD wave propagating along the field line. These lie on both sides of the corotation r

A. Moretti, S. Campana, D. Lazzati, G. Tagliaferri

We present the X-ray source number counts in two energy bands (0.5-2 and 2-10 keV) from a very large source sample: we combine data of six different surveys, both shallow wide field and deep pencil beam, performed with three different satellites (ROSAT, Chandra and XMM-Newton). The sample covers with good statistics the largest possible flux range so far: [2

R. F. Shen, L. M. Song

We have studied the averaged power density spectra (PDSs) of two classes of long-duration gamma-ray bursts in the recent classification by Balastegui et al.(2001) based on neural network analysis. Both PDSs follow a power law over a wide frequency range with approximately the same slope, which indicates that a process with a self-similar temporal property ma

Neil J. Cornish, Shane L. Larson

The Laser Interferometer Space Antenna (LISA) will operate as an AM/FM receiver for gravitational waves. For binary systems, the source location, orientation and orbital phase are encoded in the amplitude and frequency modulation. The same modulations spread a monochromatic signal over a range of frequencies, making it difficult to identify individual source

E. Vazquez-Semadeni, J. Ballesteros-Paredes, R. S. Klessen

We compile a holistic scenario for molecular cloud (MC) evolution and control of the star formation efficiency (SFE), and present a first set of numerical tests of it. A {\it lossy} compressible cascade can generate density fluctuations and further turbulence at small scales from large-scale motions, implying that the turbulence in MCs may originate from the

Alejandro Perez

In this article we review the present status of the spin foam formulation of non-perturbative (background independent) quantum gravity. The article is divided in two parts. In the first part we present a general introduction to the main ideas emphasizing their motivations from various perspectives. Riemannian 3-dimensional gravity is used as a simple example

V. A. De Lorenci, E. S. Moreira,

We show that a dispiration (a disclination plus a screw dislocation) polarizes the vacuum of a scalar field giving rise to an energy momentum tensor which, as seen from a local inertial frame, presents non vanishing off-diagonal components. The results may have applications in cosmology (chiral cosmic strings) and condensed matter physics (materials with lin

Ira Z. Rothstein

This letter is an investigation of the pion form factor utilizing recently developed effective field theory techniques. The primary results reported are: Both the transition and electromagnetic form factors are corrected at order $Λ/Q$. However, these corrections only arise due to time ordered products which are sensitive to soft components of the pion. The

Nima Arkani-Hamed, Hsin-Chia Cheng, Paolo Creminelli, Lisa Randall

We present a new model of inflation in which the inflaton is the extra component of a gauge field in a 5d theory compactified on a circle. The chief merit of this model is that the potential comes only from non-local effects so that its flatness is not spoiled by higher dimensional operators or quantum gravity corrections. The model predicts a red spectrum (

Jamal Jalilian-Marian

We argue that high gluon density effects at small $x$ are important for the calculation of ultra-high energy neutrino nucleon cross sections due to the phenomenon of geometric scaling. We calculate the cross section for $νN \to μX$, including high gluon density effects, using the all twist formalism of McLerran and Venugopalan and show that it can be related

L. Perivolaropoulos

We consider a Brans-Dicke scalar field stabilized by a general power law potential with power index $n$ at a finite equilibrium value. Redshifting matter induces oscillations of the scalar field around its equilibrium due to the scalar field coupling to the trace of the energy momentum tensor. If the stabilizing potential is sufficiently steep these high fre

A. Gusev, P. Flin, V. Pervushin, S. Vinitsky

The Kepler problem is considered in a space with the Friedmann--Lemaitre--Robertson--Walker metrics of the expanding universe. The covariant differential of the Friedmann coordinates (X=a(t)x) is considered as a possible mechanism of the formation of galaxies and clusters of galaxies. The cosmic evolution leads to decreasing energy of particles, causing free

Jun Nishimura, Soo-Jong Rey, Fumihiko Sugino

Built upon the proposal of Kaplan et.al. [hep-lat/0206109], we construct noncommutative lattice gauge theory with manifest supersymmetry. We show that such theory is naturally implementable via orbifold conditions generalizing those used by Kaplan {\sl et.al.} We present the prescription in detail and illustrate it for noncommutative gauge theories latticize

R. N. Mohapatra, M. K. Parida, G. Rajasekaran

Starting with the hypothesis that quark and lepton mixings are identical at or near the GUT scale, we show that the large solar and atmospheric neutrino mixing angles together with the small reactor angle $U_{e3}$ can be understood purely as a result of renormalization group evolution. The only requirements are that the three neutrinos must be quasi degenera

R. J. Fries, S. A. Bass, B. Muller, C. Nonaka

We argue that the emission of hadrons with transverse momentum up to about 5 GeV/c in central relativistic heavy ion collisions is dominated by recombination, rather than fragmentation of partons. This mechanism provides a natural explanation for the observed constant baryon-to-meson ratio of about one and the apparent lack of a nuclear suppression of the ba

Bedangadas Mohanty, Jan-e Alam

We have studied the rapidity distribution of secondary hadrons produced in nucleus-nucleus collisions at ultra-relativistic energies within the ambit of the Landau&#39;s hydrodynamical model. A reasonable description of the data can also be obtained by using the Bjorken&#39;s hydrodynamical model if the boost invariance is restricted to a finite rapidity ran

C. Carasco, J. Bermuth, P. Merle, P. Bartsch

Asymmetries in quasi-elastic pol 3He(pol e,e&#39;p) have been measured at a momentum transfer of 0.67 (GeV/c)^2 and are compared to a calculation which takes into account relativistic kinematics in the final state and a relativistic one-body current operator. With an exact solution of the Faddeev equation for the 3He-ground state and an approximate treatment

Saar Rahav, Ido Gilary, Shmuel Fishman

The dynamics of classical and quantum systems which are driven by a high frequency ($ω$) field is investigated. For classical systems the motion is separated into a slow part and a fast part. The motion for the slow part is computed perturbatively in powers of $ω^{-1}$ to order $ω^{-4}$ and the corresponding time independent Hamiltonian is calculated. Such a

Tarun Deep Saini, T. Padmanabhan, Sarah Bridle

We show that the distance measures (such as the luminosity and angular diameter distances) are linear functionals of the equation-of-state function w(z) of the dark energy to a fair degree of accuracy in the regimes of interest. That is, the distance measures can be expressed as a sum of (i) a constant and (ii) an integral of a weighting function multiplied

E. Burgos, Horacio Ceva, R. P. J. Perazzo

This is a comment on a paper by S. Hod and E. Nakar, published in Phys. Rev. Lett. 88, 238702 (2002)

Pavel Krtous, Jiri Podolsky

Radiative properties of gravitational and electromagnetic fields generated by uniformly accelerated charged black holes in asymptotically de Sitter spacetime are studied by analyzing the C-metric exact solution of the Einstein-Maxwell equations with a positive cosmological constant. Its global structure and physical properties are thoroughly discussed. We ex

Alexandre Arbey, Julien Lesgourgues, Pierre Salati

Dwarf spiral galaxies - and in particular the prototypical DDO 154 - are known to be completely dominated by an unseen component. The putative neutralinos - so far the favored explanation for the astronomical dark matter - fail to reproduce the well measured rotation curves of those systems because these species tend to form a central cusp whose presence is

E. L. Bratkovskaya, W. Cassing, H. Stoecker

We calculate open charm and charmonium production in $Au+Au$ reactions at $\sqrt{s}$ = 200 GeV within the hadron-string dynamics (HSD) transport approach employing open charm cross sections from $pN$ and $πN$ reactions that are fitted to results from PYTHIA and scaled in magnitude to the available experimental data. Charmonium dissociation with nucleons and

Alexander Yu. Vlasov

In this paper is presented an abstract theory of quantum processors and controllers, special kind of quantum computational network defined on a composite quantum system with two parts: the controlling and controlled subsystems. Such approach formally differs from consideration of quantum control as some external influence on a system using some set of Hamilt

Shiyin Shen, H. J. Mo, Simon D. M. White, Michael R. Blanton

abridged: We use a complete sample of about 140,000 galaxies from the Sloan Digital Sky Survey (SDSS) to study the size distribution of galaxies and its dependence on their luminosity, stellar mass, and morphological type. The large SDSS database provides statistics of unprecedented accuracy. For each type of galaxy, the size distribution at given luminosity

J. Nieves

We use standard distorted wave theory techniques and dimensional regularization to find out solutions of the nucleon-nucleon Lippman--Schwinger equation with a kernel determined by the Weinberg&#39;s next-to-leading potential, which consists of one--pion exchange and additional contact terms with derivatives. Though for simplicity, we restrict the discussion

Eric Bois, Ludmila Kiseleva-Eggleton, Nicolas Rambaux, Elke Pilat-Lohinger

The orbits in the HD 160691 planetary system at first appeared highly unstable, but using the MEGNO and FLI techniques of global dynamics analysis in the orbital parameter space we have found a stabilizing mechanism that could be the key to its existence. In order to be dynamically stable, the HD 160691 planetary system has to satisfy the following condition

Masashi Hamanaka, Kouichi Toda

We present a noncommutative version of the Burgers equation which possesses the Lax representation and discuss the integrability in detail. We find a noncommutative version of the Cole-Hopf transformation and succeed in the linearization of it. The linearized equation is the (noncommutative) diffusion equation and exactly solved. We also discuss the properti

M. Cirasuolo, M. Magliocchetti, A. Celotti, L. Danese

We present a detailed analysis of a sample of radio-detected quasars, obtained by matching together objects from the FIRST and 2dF Quasar Redshift Surveys. The dataset consists of 113 sources, spanning a redshift range 0.3 < z < 2.2, with optical magnitudes 18.25 < b_J < 20.85 and radio fluxes S_{1.4 GHz} < 1 mJy. These objects exhibit properties such as red

Z. C. Tu, Z. C. Ou-Yang

An elegant formula for coordinates of carbon atoms in a unit cell of a single-walled nanotube (SWNT) is presented and a new molecular motor of double-walled carbon nanotube whose inner tube is a long (8,4) SWNT and outer tube a short (14,8) SWNT is constructed. The interaction between inner an outer tubes is analytically derived by summing the Lennard-Jones

Andrea Quadri

It is shown that the problem of the recursive restoration of the Slavnov-Taylor (ST) identities at the quantum level for anomaly-free gauge theories is equivalent to the problem of parameterizing the local approximation to the quantum effective action in terms of ST functionals, associated with the cohomology classes of the classical linearized ST operator.