October 2003 arXiv papers

Graciela Gelmini, Paolo Gondolo, Adrian Soldatenko

We point out that if heavy metastable particles composing the dark matter of our galaxy are responsible for the ultra-high energy cosmic rays (UHECR) then the leading tidal stream of the Sagittarius dwarf galaxy could be detected through UHECR. The signal would be an anisotropy in the UHECR flux smaller than the telltale anisotropy towards the galactic cente

Philip B. Allen, Alexander G. Abanov, Ryan Requist

Triangular symmetric molecules with mirror symmetry perpendicular to the 3-fold axis are forbidden to have a fixed electrical dipole moment. However, if the ground state is orbitally degenerate and lacks inversion symmetry, then a ``quantum'' dipole moment does exist. The system of 3 electrons in D_3h symmetry is our example. This system is realized

Nélido González-Segredo, Peter V. Coveney

By means of a three-dimensional amphiphilic lattice-Boltzmann model with short-range interactions for the description of ternary amphiphilic fluids, we study how the phase separation kinetics of a symmetric binary immiscible fluid is altered by the presence of the amphiphilic species. We find that a gradual increase in amphiphile concentration slows down dom

Alberto Vallinotto, Edmund J. Copeland, Edward W. Kolb, Andrew R. Liddle

We explore the types of slow-roll inflationary potentials that result in scalar perturbations with a constant spectral index, i.e., perturbations that may be described by a single power-law spectrum over all observable scales. We devote particular attention to the type of potentials that result in the Harrison--Zel'dovich spectrum.

Massimo Ricotti, Jeremiah P. Ostriker

We investigate the possibility that there is a first phase of partial ionisation due to X-rays produced by black hole accretion in small-mass galaxies at redshifts 7<z<20. This is followed by complete reionisation by stellar sources at z~7. This scenario is motivated by the large optical depth to Thompson scattering, tau_e=0.17, measured by WMAP. But it is a

M. Rheinhardt, D. Konenkov, U. Geppert

In former papers we showed that during the decay of a neutron star&#39;s magnetic field under the influence of the Hall--drift, an unstable rise of small--scale field structures at the expense of the large--scale background field may happen. This linear stability analysis was based on the assumption of a uniform density throughout the neutron star crust, whe

R. L. Jaffe, A. Scardicchio

We propose a new approach to the Casimir effect based on classical ray optics. We define and compute the contribution of classical optical paths to the Casimir force between rigid bodies. We reproduce the standard result for parallel plates and agree over a wide range of parameters with a recent numerical treatment of the sphere and plate with Dirichlet boun

Ofer Aharony, Joseph Marsano, Shiraz Minwalla, Kyriakos Papadodimas

We demonstrate that weakly coupled, large N, d-dimensional SU(N) gauge theories on a class of compact spatial manifolds (including S^{d-1} \times time) undergo deconfinement phase transitions at temperatures proportional to the inverse length scale of the manifold in question. The low temperature phase has a free energy of order one, and is characterized by

Richard S. De Simone, Xiaoan Wu, Scott Tremaine

We explore the heating of the velocity distribution in the solar neighbourhood by stochastic spiral waves. Our investigation is based on direct numerical integration of initially circular test-particle orbits in the sheared sheet. We confirm the conclusion of other investigators that heating by spiral structure can explain the principal features of the age-v

A. W. Rengstorf, S. L. Mufson, C. Abad, B. Adams

By observing the high galactic latitude equatorial sky in drift scan mode with the QUEST (QUasar Equatorial Survey Team) Phase 1 camera, multi-bandpass photometry on a large strip of sky, resolved over a large range of time scales (from hourly to biennially) has been collected. A robust method of ensemble photometry revealed those objects within the scan reg

Lizzie Burslem, Amie Wilkinson

In this paper we find all solvable subgroups of Diff^omega(S^1) and classify their actions. We also investigate the C^r local rigidity of actions of the solvable Baumslag-Solitar groups on the circle. The investigation leads to two novel phenomena in the study of infinite group actions on compact manifolds. We exhibit a finitely generated group Gamma and a m

Alexandre Eremenko, Sergei Merenkov

We show that for every non-negative integer d, there exist differential equations w&#39;&#39;+Pw=0, where P is a polynomial of degree d, such that some non-trivial solution w has all zeros real.

Walter Bergweiler, Alexandre Eremenko

We show that if a meromorphic function has two completely invariant Fatou components and only finitely many critical and asymptotic values, then its Julia set is a Jordan curve. However, even if both domains are attracting basins, the Julia set need not be a quasicircle. We also show that all critical and asymptotic values are contained in the two completely

Evgeny Ivanov, Sergey Krivonos, Olaf Lechtenfeld

Proceeding from nonlinear realizations of the most general N=4, d=1 superconformal symmetry associated with the supergroup D(2,1;α), we construct all known and two new off-shell N=4, d=1 supermultiplets as properly constrained N=4 superfields. We find plenty of nonlinear interrelations between the multiplets constructed and present a few examples of invarian

J. S. Perkins, H. Krawczynski, P. Dowkontt

We present the results of using standard IMARAD CZT detectors with a 100 MHz readout of the anode and cathode pulses. The detectors, 2 cm x 2 cm large and 0.5 cm thick, have 64 Indium pixellated anode contacts at a pitch of 2.5 mm. We investigate the possibilities to improve on the detector&#39;s photo-peak efficiency and energy resolution using two depth of

Mark A. Rubin

The Everett-interpretation description of isolated measurements, i.e., measurements involving interaction between a measuring apparatus and a measured system but not interaction with the environment, is shown to be unambiguous, claims in the literature to the contrary notwithstanding. The appearance of ambiguity in such measurements is engendered by the fact

Sandro Sorella, Seiji Yunoki

We define a numerical scheme that allows to approximate a given Hamiltonian by an effective one, by requiring several constraints determined by exact properties of generic &#39;&#39;short range&#39;&#39; Hamiltonians. In this way the standard lattice fixed node is also improved as far as the variational energy is concerned. The effective Hamiltonian is defin

D. Bauer

Semi-classical molecular dynamics simulations of small rare gas clusters in short laser pulses of 100 nm wavelength were performed. For comparison, the cluster response to 800 nm laser pulses was investigated as well. The inner ionization dynamics of the multi-electron atoms inside the cluster was treated explicitly. The simulation results underpin that at X

Gunnar Björk, Piero G. Luca Mana

An operational measure to quantify the sizes of some ``macroscopic quantum superpositions&#39;&#39;, realized in recent experiments, is proposed. The measure is based on the fact that a superposition presents greater sensitivity in interferometric applications than its superposed constituent states. This enhanced sensitivity, or ``interference utility&#39;&#

John Cardy

We show that, in any conformal field theory, the weights of all bulk primary fields that couple to N phi_{2,1} fields on the boundary are given by the spectrum of an N-particle Calogero-Sutherland model. The corresponding correlation function is simply related to the N-particle wave function. Examples are discussed for the minimal models and for the non-unit

Jelena Stajic, Suncica Elezovic-Hadzic

We study Hamiltonian walks (HWs) on Sierpinski and $n$--simplex fractals. Via numerical analysis of exact recursion relations for the number of HWs we calculate the connectivity constant $ω$ and find the asymptotic behaviour of the number of HWs. Depending on whether or not the polymer collapse transition is possible on a studied lattice, different scaling r

S. Munier, R. Peschanski

We propose a general method to study the solutions to nonlinear QCD evolution equations, based on a deep analogy with the physics of traveling waves. In particular, we show that the transition to the saturation regime of high energy QCD is identical to the formation of the front of a traveling wave. Within this physical picture, we provide the expressions fo

Shin&#39;ichi Nojiri, Sergei D. Odintsov

One possibility to explain the current accelerated expansion of the universe may be related with the presence of cosmologically evolving scalar whose mass depends on the local matter density (chameleon cosmology). We point out that matter quantum effects in such scalar-tensor theory produce the chameleon scalar field dependent conformal anomaly. Such conform

T. P. T. Dijkstra, B. Gato-Rivera, F. Riccioni, A. N. Schellekens

The aim of this paper is to study orientifolds of c=1 conformal field theories. A systematic analysis of the allowed orientifold projections for c=1 orbifold conformal field theories is given. We compare the Klein bottle amplitudes obtained at rational points with the orientifold projections that we claim to be consistent for any value of the orbifold radius

J. D. Vergados, P. Quentin, D. Strottman

The recent WMAP data have confirmed that exotic dark matter together with the vacuum energy (cosmological constant) dominate in the flat Universe. Supersymmetry provides a natural dark matter candidate, the lightest supersymmetric particle (LSP). Thus the direct dark matter detection is central to particle physics and cosmology. Most of the research on this

Hrvoje Stefancic

We examine cosmological models with generalized phantom energy (GPE). Generalized phantom energy satisfies the supernegative equation of state, but its evolution with the scale factor is generally independent, i.e. not determined by its equation of state. The requirement of general covariance makes the gravitational constant time-dependent. It is found that

Dumitru Astefanesei, Eugen Radu

We consider rotating boson star solutions in a three-dimensional anti-de Sitter spacetime and investigate the influence of the rotation on their properties. The mass and angular momentum of these configurations are computed by using the counterterm method. No regular solution is found in the limit of vanishing cosmological constant.

Andrea Quadri

A power-counting renormalizable model into which massive Yang-Mills theory is embedded is analyzed. The model is invariant under a nilpotent BRST differential s. The physical observables of the embedding theory, defined by the cohomology classes of s in the Faddeev-Popov neutral sector, are given by local gauge-invariant quantities constructed only from the

Norio Konno

There has recently been considerable interest in quantum walks in connection with quantum computing. The walk can be considered as a quantum version of the so-called correlated random walk. We clarify a strong structural similarity between both walks and study limit theorems and absorption problems for correlated random walks by our PQRS method, which was us

M. V. Cheremisin

The beating pattern of Shubnikov-de Haas oscillations is reproduced in both the crossed and tilted magnetic field configuration and in presence of zero-field valley splitting in Si-MOSFET system. The consequences of IQHE in extremely dilute 2DEG are discussed.

Jan T. Sobczyk

We perform a detail analysis of two models of neutrino CC Delta production on free nucleons. First model is a standard one based on nucleon-Delta transition current with several form-factors. Second model is a starting point for a construction of Marteau model with sophisticated analytical computations of nuclear effects. We conclude that both models lead to

Klaus Dolag, Dario Grasso, Volker Springel, Igor Tkachev

We construct a map of deflections of ultra-high energy cosmic rays by extragalactic magnetic fields using a magneto-hydrodynamical simulation of cosmic structure formation that realistically reproduces the positions of known galaxy clusters in the Local Universe. Large deflection angles occur in cluster regions, which however cover only an insignificant frac

Fabrizio Tamburini, Bruce Bassett, Antonio Bianchini, Alberto Franceschini

The paper has been deeply reviewed and compeltely re-written.

Gianluca Grignani, Donatella Marmottini, Pasquale Sodano

Using the recently proposed generalization to an arbitrary number of colors of the strong coupling approach to lattice gauge theories\cite{Grignani:2003uv}, we compute the chiral condensate of massless QCD in the &#39;t Hooft limit.

C. D. Westbrook, R. C. Ball, P. R. Field, A. J. Heymsfield

Aggregation of ice crystals is a key process governing precipitation. Individual ice crystals exhibit considerable diversity of shape, and a wide range of physical processes could influence their aggregation; despite this we show that a simple computer model captures key features of aggregate shape and size distribution reported recently from Cirrus clouds.

Erik Sjöqvist

The nonlocal and topological nature of the molecular Aharonov-Bohm (MAB) effect is examined for real electronic Hamiltonians. A notion of preferred gauge for MAB is suggested. The MAB effect in the linear + quadratic $E\otimes ε$ Jahn-Teller system is shown to be essentially analogues to an anisotropic Aharonov-Casher effect for an electrically neutral spin$

V. Ryzhii

We consider the effect of microwave radiation on the Hall resistivity in two-dimension electron systems. It is shown that the photon-assisted impurity scattering of electrons can result in oscillatory dependences of both dissipative and Hall components of the conductivity and resistivity tensors on the ratio of radiation frequency to cyclotron frequency. The

Dipankar Chakrabarti, A. Harindranath, Lubomir Martinovic, Grigorii B. Pivovarov

We present nonperturbative light-front energy eigenstates in the broken phase of a two dimensional $\fracλ{4!}ϕ^4$ quantum field theory using Discrete Light Cone Quantization and extrapolate the results to the continuum limit. We establish degeneracy in the even and odd particle sectors and extract the masses of the lowest two states and the vacuum energy de

Hai-Yang Cheng, Chun-Khiang Chua, Chien-Wen Hwang

We study the decay constants and form factors of the ground-state s-wave and low-lying p-wave mesons within a covariant light-front approach. Numerical results of the form factors for transitions between a heavy pseudoscalar meson and an s-wave or p-wave meson and their momentum dependence are presented in detail. In particular, form factors for heavy-to-lig

Julien Barre&#39;, Thierry Dauxois, Giovanni De Ninno, Duccio Fanelli

We propose a new approach, based on statistical mechanics, to predict the saturated state of a single-pass, high-gain free-electron laser (FEL). In analogy with the violent relaxation process in self-gravitating systems and in the Euler equation of 2D turbulence, the initial relaxation of the laser can be described by the statistical mechanics of an associat

Yuri Ozhigov

A quantum unitary evolution alternated with measurements is simulated by a bubble filled with fictitious particles called amplitude quanta that move chaotically and can be transformed by the simple rules that look like chemical reactions. A basic state of simulated system is treated as a collision of the two corresponding amplitude quanta, that gives the qua

Myoung Won Cho, Seunghwan Kim

It is known that magnetic vortices in two dimensional Heisenberg models with easy-plane anisotropy exhibit an instability depending on the anisotropy strength. In this paper, we study the statistic behavior of the two-dimensional easy-plane Heisenberg models with distance-dependent interactions, $J_{xy}(r)$ and $J_z(r)$ for in-plane and out-of-plane componen

Myoung Won Cho, Seunghwan Kim

In animal experiments, the observed orientation preference (OP) and ocular dominance (OD) columns in the visual cortex of the brain show various pattern types. Here, we show that the different visual map formations in various species are due to the crossover behavior in anisotropic systems composed of orientational and scalar components such as easy-plane He

Kazue Kudo, Tetsuo Deguchi

The level-spacing distribution of a spin 1/2 XXZ chain is numerically studied under random magnetic field. We show explicitly how the level statistics depends on the lattice size L, the anisotropy parameter $Δ$, and the mean amplitude of the random magnetic field h. In the energy spectrum, quantum integrability competes with nonintegrability derived from the

Jacek Pawelczyk, Rafal R. Suszek

An algebraic formulation of the stringy geometry on simple current orbifolds of the WZW models of type A_N is developed within the framework of Reflection Equation Algebras, REA_q(A_N). It is demonstrated that REA_q(A_N) has the same set of outer automorphisms as the corresponding current algebra A^{(1)}_N which is crucial for the orbifold construction. The

Mokhtar Aouina, John R. Klein

For a closed PL manifold M, we consider the configuration space F(M,k) of ordered k-tuples of distinct points in M. We show that a suitable iterated suspension of F(M,k) is a homotopy invariant of M. The number of suspensions we require depends on three parameters: the number of points k, the dimension of M and the connectivity of M. Our proof uses a mixture

J. D. Bashford, P. D. Jarvis, J. G. Sumner, M. A. Steel

An analysis of the Kimura 3ST model of DNA sequence evolution is given on the basis of its continuous Lie symmetries. The rate matrix commutes with a U(1)xU(1)xU(1) phase subgroup of the group GL(4) of 4x4x4 invertible complex matrices acting on a linear space spanned by the 4 nucleic acid base letters. The diagonal `branching operator&#39; representing spec

G. L. Delzanno, G. Lapenta, M. Rosenberg

We present a simulation study of the charging of a dust grain immersed in a plasma, considering the effect of electron emission from the grain (thermionic effect). It is shown that the OML theory is no longer reliable when electron emission becomes large: screening can no longer be treated within the Debye-Huckel approach and an attractive potential well for

Apollo Go

A pair of $B^0\bar B^0$ mesons from $Υ(4S)$ decay exhibit EPR type non-local particle-antiparticle (flavor) correlation. It is possible to write down Bell Inequality (in the CHSH form: $S\le2$) to test the non-locality assumption of EPR. Using semileptonic $B^0$ decays of $Υ(4S)$ at Belle experiment, a clear violation of Bell Inequality in particle-antiparti

Bao-Sen Shi, Akihisa Tomita

In this paper, we demonstrate efficient generation of collinearly propagating, degenerate pulsed photon pairs based on a bulk Periodically Poled Potassium Titanyl Phosphate pumped by an ultrashort pulse laser. Using a single-mode fiber as a spatial mode filter, we detect about 3200 coincidence counts per second per milliwatt pump power. After we consider mai

S. Tewari, S. M. Brown, P. Kenyon, M. Balcerzak

While it is not possible to directly the observe evolution of multigene families, the best alternative is to compare orthologous family members among several closely-related species with varying degrees of reproductive isolation. Using RT-PCR we show that in pea (Pisum sativum) each member of the pathogenesis-related PR10 family has a distinct pattern of exp

Joel Heinrich

The value of the likelihood is occasionally used by high energy physicists as a statistic to measure goodness-of-fit in unbinned maximum likelihood fits. Simple examples are presented that illustrate why this (seemingly intuitive) method fails in practice to achieve the desired goal.

Metod Saniga, Rosolino Buccheri

The paper presents, to our knowledge, a first fairly comprehensive and mathematically well-underpinned classification of the psychopathology of time (and space). After reviewing the most illustrative first-person accounts of &#34;anomalous/peculiar&#34; experiences of time (and, to a lesser degree, also space) we introduce and describe in detail their algebr

Ken Sasaki

We examine the spinning behavior of egg-shaped axisymmetric bodies whose cross sections are described by several oval curves similar to real eggs with thin and fat ends. We use the gyroscopic balance condition of Moffatt and Shimomura and analyze the slip velocity of the bodies at the point of contact as a function of $θ$, the angle between the axis of symme

S. Shlomo, V. M. Kolomietz, B. K. Agrawal

We calculate the transition density for the overtone of the isosclar giant monopole resonance (ISGMR) from the response to an appropriate external field $\hat{f}_ξ(r)$ obtained using the seemiclassical fluid dynamic approximation and the Hartree-Fock (HF) based random phase approximation (RPA). We determine the mixing parameter $ξ$ by maximizing the ratio of

A. Covello, L. Coraggio, A. Gargano, N. Itaco

Odd-odd nuclei around double shell closures are a direct source of information on the proton-neutron interaction between valence nucleons. We have performed shell-model calculations for doubly odd nuclei close to $^{208}$Pb, $^{132}$Sn and $^{100}$Sn using realistic effective interactions derived from the CD-Bonn nucleon-nucleon potential. The calculated res

A. I. Machavariani

A new kind of the relativistic three-body equations for the three fermion systems are suggested. These equations are derived in the framework of the standard field-theoretical $S$-matrix approach in the time-ordered three dimensional form. Therefore corresponding relativistic covariant equations are three-dimensional from the beginning. The solutions of the

Zoltan Batiz, Franz Gross

We introduce a generalization of 1+1 dimensional large Nc QCD, which we refer to as ``reduced&#39;&#39; QCD, or rQCD. In this model gluons and quark momenta live in 1+1 dimensions only, but the quark spin and all other particles (leptons, and the photon) live in the full 1+3 dimensions. The bound states of quarks and antiquarks are identical to those origina

W. P. Tan, S. R. Souza, R. J. Charity, R. Donangelo

We develop an improved Statistical Multifragmentation Model that provides the capability to calculate calorimetric and isotopic observables with precision. With this new model we examine the influence of nuclear isospin on the fragment elemental and isotopic distributions. We show that the proposed improvements on the model are essential for studying isospin

M. Caamano, D. Cortina-Gil, K. Suemmerer, J. Benlliure

We have measured production cross sections and longitudinal momentum distributions of fragments from neutron-deficient 36Ar at 1.05 A.GeV. The production cross-sections show excellent agreement with the predictions of the semiempirical formula EPAX. We have compared these results, involving extremly neutron deficient nuclei, with model calculations to extrac

B. Grammaticos, A. Ramani, Y. Ohta

We present a geometric description, based on the affine Weyl group E_{6}^{(1)}, of two discrete analogues of the Painlevé VI equation, known as the asymmetric q-P_{V} and asymmetric d-P_{IV}. This approach allows us to describe in a unified way the evolution of the mapping along the independent variable and along the various parameters (the latter evolution

A. V. Tsiganov, O. V. Goremykin

We consider two-site XXX Heisenberg magnets with different boundary conditions, which are integrable systems on so(4) possessing additional cubic and quartic integrals of motion. The separated variables for these models are constructed using the Sklyanin method.

Sibel Baskal, Elena Georgieva, Y. S. Kim

According to Eugene Wigner, quantum mechanics is a physics of Fourier transformations, and special relativity is a physics of Lorentz transformations. Since two-by-two matrices with unit determinant form the group SL(2,c) which acts as the universal covering group of the Lorentz group, the two-by-two matrices constitute the natural language for special relat

Nils Bruin

We determine the rational integers x,y,z such that x^3+y^9=z^2 and gcd(x,y,z)=1. First we determine a finite set of curves of genus 10 such that any primitive solution to x^3+y^9=z^2 corresponds to a rational point on one of those curves. We observe that each of these genus 10 curves covers an elliptic curve over some extension of Q. We use this cover to app

Paul Jung

The symmetric exclusion process and the voter model are two interacting particle systems for which a dual finite particle system allows one to characterize its invariant measures. Adding spontaneous births and deaths to the two processes still allows one to use the dual to obtain information about the original process. We study the noisy voter-exclusion proc

S. V. Shadrin

We reduce the calculation of the simplest Hodge integrals to some sums over decorated trees. Since Hodge integrals are already calculated, this gives a proof of a rather interesting combinatorial theorem and a new representation of Bernoulli numbers.

B. Agrebaoui, M. Ben Ammar, N. Ben Fraj, V. Ovsienko

We study non-trivial deformations of the natural action of the Lie algebra $\mathrm{Vect}({\mathbb R}^n)$ on the space of differential forms on ${\mathbb R}^n$. We calculate abstractions for integrability of infinitesimal multi-parameter deformations and determine the commutative associative algebra corresponding to the miniversal deformation in the sense of

Aldo Conca

The Castelnuovo-Mumford regularity $\reg(I)$ is one of the most important invariants of a homogeneous ideal $I$ in a polynomial ring. A basic question is how the regularity behaves with respect to taking powers of ideals. It is known that in the long-run $\reg(I^k)$ is a linear function of $k$. We show that in the short-run the regularity of $I^k$ can be qui

V. Manuilov, K. Thomsen

Let $A$, $B$ be C*-algebras; $A$ separable, $B$ $σ$-unital and stable. We introduce a notion of translation invariance for asymptotic homomorphisms from $SA=C_0(\mathbb R)\otimes A$ to $B$ and show that the Connes-Higson construction applied to any extension of $A$ by $B$ is homotopic to a translation invariant asymptotic homomorphism. In the other direction

V. Manuilov, K. Thomsen

We consider the semigroup $Ext(A,B)$ of extensions of a separable C*-algebra $A$ by a stable C*-algebra $B$ modulo unitary equivalence and modulo asymptotically split extensions. This semigroup contains the group $Ext^{-1/2}(A,B)$ of invertible elements (i.e. of semi-invertible extensions). We show that the functor $Ext^{1/2}(A,B)$ is homotopy invariant and

David Ben-Zvi, Thomas Nevins

We present a bridge between the KP soliton equations and the Calogero-Moser many-body systems through noncommutative algebraic geometry. The Calogero-Moser systems have a natural geometric interpretation as flows on spaces of spectral curves on a ruled surface. We explain how the meromorphic solutions of the KP hierarchy have an interpretation via a noncommu

Wolfgang Lueck

We give a survey on L^2-invariants such as L^2-Betti numbers and L^2-torsion taking an algebraic point of view. We discuss their basic definitions, properties and applications to problems arising in topology, geometry, group theory and K-theory.

Olle Haeggstroem, Christof Kuelske

We study Gibbs properties of the fuzzy Potts model in the mean field case (i.e on a complete graph) and on trees. For the mean field case, a complete characterization of the set of temperatures for which non-Gibbsianness happens is given. The results for trees are somewhat less explicit, but we do show for general trees that non-Gibbsianness of the fuzzy Pot

Manuel Blickle

A simple formula computing the multiplier ideal of a monomial ideal on an arbitrary affine toric variety is given. Variants for the multiplier module and test ideals are also treated.

Thomas Bauer, Thomas Peternell

We investigate the structure of smooth projective 3-folds X with -K_X nef and K_X^3=0.

Sheng-Li Tan, De-Qi Zhang

We express explicitly the integral closures of some ring extensions; this is done for all Bring-Jerrard extensions of any degree as well as for all general extensions of degree < 6; so far such an explicit expression is known only for degree < 4 extensions. As a geometric application we present explicitly the structure sheaf of every Bring-Jerrard covering s

Roberto Paoletti

Suppose given an Hamiltonian action of a compact semisimple Lie group on a polarized complex projective manifold $(M,L)$. We study by means of microlocal techniques the local and global asymptotic behaviour of linear series on $M$ defined in terms of the action and the irreducible representations of $G$.

Jean-Camille Birget

We prove new results about the remarkable infinite simple groups introduced by Richard Thompson in the 1960s. We define the groups as partial transformation groups and we give a faithful representation in the Cuntz C*-algebra. For the finitely presented simple group T_fin (also known as V) we show that the word-length and the table size satisfy an n log n re

H. Weigel

We study the vacuum polarization (Casimir) energy in renormalizable, continuum quantum field theory in the presence of a background field, designed to impose Dirichlet boundary conditions on the fluctuating quantum field. In two and three spatial dimensions the Casimir energy diverges as a background field becomes concentrated on the surface on which the Dir

B. Kleihaus, J. Kunz, K. Myklevoll

We construct sphaleron solutions in Weinberg-Salam theory, which possess only discrete symmetries. Related to rational maps of degree N, these sphalerons carry baryon number Q_B=N/2. The energy density of these sphalerons reflects their discrete symmetries. We present an N=3 sphaleron with tetrahedral energy density, an N=4 sphaleron with cubic energy densit

M. Gasperini

We present a model of dark energy based on the string effective action, and on the assumption that the dilaton is strongly coupled to dark matter. We discuss the main differences between this class of models and more conventional models of quintessence,uncoupled to dark matter. This paper is based on talks presented at the &#34;VII Congresso Nazionale di Cos

N. Beisert, M. Bianchi, J. F. Morales, H. Samtleben

We test the spectrum of string theory on AdS_5 x S^5 derived in hep-th/0305052 against that of single-trace gauge invariant operators in free N=4 super Yang-Mills theory. Masses of string excitations at critical tension are derived by extrapolating plane-wave frequencies at g_{YM}=0 down to finite J. On the SYM side, we present a systematic description of th

T. Banks, W. Fischler

We present a new version of holographic cosmology, which is compatible with present observations. A primordial $p=ρ$ phase of the universe is followed by a brief matter dominated era and a brief period of inflation, whose termination heats the universe. The flatness and horizon problems are solved by the $p=ρ$ dynamics. The model is characterized by two para

R. Clarkson, A. M. Ghezelbash, R. B. Mann

We show that the class of four-dimensional Taub-Bolt(NUT) spacetimes with positive cosmological constant for some values of NUT charges are stable and have entropies that are greater than that of de Sitter spacetime, in violation of the entropic N-bound conjecture. We also show that the maximal mass conjecture, which states &#34;any asymptotically dS spaceti

S. Hesselbach, O. Kittel, G. Moortgat-Pick, W. Oeller

Several results obtained within the SUSY group of the ECFA/DESY linear collider study are presented: (i) a possibility to determine tan beta and the trilinear couplings A_f via polarisation in sfermion decays, (ii) the impact of complex MSSM parameters on the third generation sfermion decays, (iii) determination of CP violation in the complex MSSM via T-odd

C. P. Burgess, N. S. Dzhalilov, M. Maltoni, T. I. Rashba

We update the best constraints on fluctuations in the solar medium deep within the solar Radiative Zone to include the new SNO-salt solar neutrino measurements. We find that these new measurements are now sufficiently precise that neutrino oscillation parameters can be inferred independently of any assumptions about fluctuation properties. Constraints on flu

K. -P. O. Diener, S. Dittmaier, W. Hollik

We calculate the O(alpha) electroweak corrections to charged- and neutral-current deep-inelastic neutrino scattering off an isoscalar target. The full one-loop-corrected cross sections, including hard photonic corrections, are evaluated and compared to an earlier result which was used in the NuTeV analysis. In particular, we compare results that differ in in

Shan-Gui Zhou

I present some recent applications of a light cone QCD-inspired model with the mass squared operator consisting of a harmonic oscillator potential as confinement in the meson spectra. The model gives an universal and satisfactory description of both singlet and triplet states of S-wave mesons. In the present work P-wave D_s mesons are also investigated. The

U. Aglietti, R. Sghedoni, L. Trentadue

The full O(alpha_S) transverse momentum distribution for the b -> s+gamma decay is computed. Results are presented in analytic form. An improved expression for the coefficient function taking into account subleading operators is given and an exact expression for the remainder function associated with the leading operator O_7 is also derived.

D. Kharzeev, K. Tuchin

We consider the production of open charm in heavy ion collisions in the framework of the Color Glass Condensate. In the central rapidity region at RHIC, for the charm quark yield we expect N(coll) (number of collisions) scaling in the absence of final-state effects. At higher energies, or forward rapidities at RHIC, the saturation scale exceeds the charm qua

C. Csaki, C. Grojean, J. Hubisz, Y. Shirman

We consider fermions on an extra dimensional interval. We find the boundary conditions at the ends of the interval that are consistent with the variational principle, and explain which ones arise in various physical circumstances. We apply these results to higgsless models of electroweak symmetry breaking, where electroweak symmetry is not broken by a scalar

S. Digal, S. Fortunato, H. Satz

Parton percolation provides geometric deconfinement in the pre-equilibrium stage of nuclear collisions. The resulting parton condensate can lead to charmonium suppression. We formulate a local percolation condition viable for non-uniform collision environments and show that it correctly reproduces the suppression observed for S-U and Pb-Pb collisions at the

Shan-Gui Zhou, Hans-Christian Pauli

We show that the mass of the recently found meson, Ds(2317) could be reproduced by an effective light cone Hamiltonian model with a harmonic oscillator potential as confinement -- the light cone harmonic oscillator model.

SCALAR Collaboration, Teiji Kunihiro, Shin Muroya, Atsushi Nakamura

We explore whether &#34;f$_{0}$(600) or $σ$&#34; exists as a pole in QCD, by a full lattice QCD simulation on the $8^{3} \times 16$ lattice using the plaquette action and Wilson fermions. It is shown that a low-mass $σ$ pole exists owing to the disconnected diagram of the meson propagator. A discussion is given on the physical content of the $σ$.

F. J. Yndurain

In these notes we present an introductory review on various topics about low energy pion physics (some kaon physics is discussed as well). Among these, we include the uses of analyticity and unitarity to describe partial wave amplitudes (for which we give accurate and economical parametrizations) and form factors; (forward) dispersion relations; and the use

Fabio L. Braghin

The relevance of the pion mass, provenient from a term which explicitely breaks chiral symmetry in the Lagrangian, for nucleon magnetic moment in the frame of the Skyrmion model in two different versions: the usual Skyrme model and a modified one which includes a coupling to a light scalar meson field, the sigma $σ(\simeq 500-600$ MeV). The results are compa

T. Blum

I present a preliminary calculation of the hadronic vacuum polarization for 2+1 flavors of improved Kogut-Susskind quarks by utilizing a set of gauge configurations recently generated by the MILC collaboration. The polarization function $Π(q^2)$ is then used to calculate the lowest order (in $α_{QED}$) hadronic contribution to the muon anomalous magnetic mom

Andreas S. Kronfeld

This paper is a review of heavy quarks in lattice gauge theory, focusing on methodology. It includes a status report on some of the calculations that are relevant to heavy-quark spectroscopy and to flavor physics.

Michael Burghard Smy

The time variation of the elastic scattering rate of solar neutrinos with electrons in Super-Kamiokande-I was fit to the day/night variations expected from active two-neutrino oscillations in the Large Mixing Angle region. Combining Super-Kamiokande measurements with other solar and reactor neutrino data, the mixing angle is determined as sin^2theta=0.276+0.

Thomas Kluge

Event shapes and jet shapes in neutral current deep inelastic scattering and photoproduction are studied with the H1 and ZEUS detectors at HERA. The measurements are compared to next-to-leading-order QCD calculations and Monte Carlo models. The strong coupling constant is determined from subjet multiplicities.