September 2002 arXiv papers — page 14

B. Koenig, K. Fuhrmann, R. Neuhaeuser, D. Charbonneau

We present an H-band image of the companion of Chi 1 Orionis taken with the Keck adaptive optic system and NIRC2 camera equipped with a 300mas-diameter coronographic mask. The direct detection of this companion star enables us to calculate dynamical masses using only Kepler's laws M_A = 1.01 +/- 0.13 M_Sun, M_B = 0.15 +/- 0.02 M_Sun, and to study stellar

P. J. E. Peebles

Physical science has changed in the century since Lord Kelvin's celebrated essay on Nineteenth Century Clouds over the Dynamical Theory of Heat and Light, but some things are the same. Analogs in what was happening in physics then and what is happening in astronomy today serve to remind us why we can be confident the Virtual Observatory of the twenty-fir

HEGRA Collaboration, F. A. Aharonian

A search for potential point sources of very high energy gamma rays has been carried out on the data taken simultaneously by the HEGRA AIROBICC and Scintillator arrays from August 1994 to March 2000. The list of sought sources includes supernova remnants, pulsars, AGNs and binary systems. The energy threshold is around 15 TeV. For the Crab Nebula, a modest e

T. V. Mishenina, V. V. Kovtyukh, C. Soubiran, C. Travaglio

We present new observations of copper and zinc abundances in 90 metal-poor stars, belonging to the metallicity range -3< [Fe/H] < -0.5. The present study is based on high resolution spectroscopic measurements collected at the Haute Provence Observatoire (R= 42000, S/N > 100). The trend of Cu and Zn abundances as a function of the metallicity [Fe/H] is discus

M. V. Sazhin, G. Sironi, O. S. Khovanskaya

The polarization of the Cosmic Microwave Background (CMB)is a powerful observational tool at hand for modern cosmology. It allows to break the degeneracy of fundamental cosmological parameters one cannot obtain using only anisotropy data and provides new insight into conditions existing in the very early Universe. Many experiments are now in progress whose a

S. Bardelli, T. Venturi, E. Zucca, S. De Grandi

In this paper we study A3560, a rich cluster at the southern periphery of the A3558 complex, a chain of interacting clusters in the central part of the Shapley Concentration supercluster. From a ROSAT-PSPC map we find that the X-ray surface brightness distribution of A3560 is well described by two components, an elliptical King law and a more peaked and fain

R. G. Sharp, C. N. Sabbey, A. K. Vivas, A. Oemler

We combine deep, wide-field near-IR and optical imaging to demonstrate a reddening-independent quasar selection technique based on identifying outliers in the (g-z) / (z-H) colour diagram. In three fields covering a total of ~0.7 deg^2 to a depth of m_H~18, we identified 68 quasar candidates. Follow-up spectroscopy for 32 objects from this candidate list con

Vittorio Gorini, Alexander Kamenshchik, Ugo Moschella

In this note two cosmological models representing the flat Friedmann Universe filled with a Chaplygin fluid, with or without dust, are analyzed in terms of the recently proposed &#34;statefinder&#34; parameters. Trajectories of both models in the parameter plane are shown to be significantly different w.r.t. &#34;quiessence&#34; and &#34;tracker&#34; models.

Alessia Gualandris, Monica Colpi, Andrea Possenti

Was the black hole in XTE J1118+480 ejected from a globular cluster or kicked away from the galactic disk?

Monica Colpi, Alessia Gualandris, Andrea Possenti

NGC6752 hosts in its halo PSR J1911-5958A, a newly discovered binary millisecond pulsar which is the most distant pulsar ever known from the core of a globular cluster. Interestingly, its recycling history seems in conflict with a scenario of ejection resulting from ordinary stellar dynamical encounters. A scattering event off a binary system of two black ho

L. Pentericci, J. D. Kurk, C. L. Carilli, D. E. Harris

We present results from a Chandra X-ray Observatory study of the field X-ray source population in the vicinity of the radio galaxy MRC 1138-262. Many serendipitous X-ray sources are detected in an area of 8&#39;x8&#39; around the radio source and 90% are identified in our deep VLT images. The space density of such sources is higher than expected on the basis

M. Bellazzini, F. R. Ferraro, L. Origlia, E. Pancino

We present (V,I) photometry of two wide (~25 X 25 arcmin^2) fields centered on the low surface brightness dwarf spheroidal galaxies Draco and Ursa Minor. New estimates of the distance to these galaxies are provided ((m-M)_0(UMi)=19.41 \pm 0.12 and (m-M)_0(Dra)=19.84 \pm 0.14) and a comparative study of their evolved stellar population is presented. We detect

Yu. L. Bukhmastova

The distribution function of quasars with respect to apparent brightness is given, found under the assumption that quasars are, at least partially, the gravitationally enhanced images of the active nuclei of distant galaxies. A Schechter law and a two-power law for the luminosity function of the sources are used, as well as a probabilistic law of image enhan

Jeffrey Weeks, Roland Lehoucq, Jean-Philippe Uzan

When the density parameter is close to unity, the universe has a large curvature radius independently of its being hyperbolic, flat, or spherical. Whatever the curvature, the universe may have either a simply connected or a multiply connected topology. In the flat case, the topology scale is arbitrary, and there is no a priori reason for this scale to be of

M. G. Hidas, J. K. Webb, M. C. B. Ashley, C. H. Lineweaver

We are setting up a new search for transiting extrasolar planets using the 0.5m Automated Patrol Telescope at Siding Spring Observatory, Australia. We will begin regular observations in September 2002. We expect to find ~7 new planets per year.

Aigen Li

It has been suggested by a number of authors that the 2.7K cosmic microwave background (CMB) radiation might have arisen from the radiation from Population III objects thermalized by conducting cosmic graphite/iron needle-shaped dust. Due to lack of an accurate solution to the absorption properties of exceedingly elongated grains, in existing literature whic

Charles H. Lineweaver, Tamara M. Davis

It is sometimes asserted that the rapidity of biogenesis on Earth suggests that life is common in the Universe. We critically examine the assumptions inherent in this argument. Using a lottery model for biogenesis in the Universe, we convert the observational constraints on the rapidity of biogenesis on Earth into constraints on the probability of biogenesis

M. L. McConnell, J. M. Ryan, D. M. Smith, R. P. Lin

Polarization measurements of hard X-rays from solar flares can provide a direct handle on the extent to which the accelerated electrons are beamed, which, in turn, has important implications for particle acceleration models. Past efforts to measured X-ray polarization have met with only limited success. Although designed primarily as a hard X-ray imager and

Charles H. Lineweaver, Daniel Grether, Marton Hidas

Among the billions of planetary systems that fill the Universe, we would like to know how ours fits in. Exoplanet data can already be used to address the question: How common are Jupiters? Here we discuss a simple analysis of recent exoplanet data indicating that Jupiter is a typical massive planet rather than an outlier. A more difficult question to address

Kayll Lake

A class of spherically symmetric spacetimes invariantly defined by a zero flux condition is examined first from a purely geometrical point of view and then physically by way of Einstein&#39;s equations for a general fluid decomposition of the energy-momentum tensor. The approach, which allows a formal inversion of Einstein&#39;s equations, explains, for exam

H. Schmidt, J. F. Zasadzinski, K. E. Gray, D. G. Hinks

Tunneling data on magnesium diboride, MgB_2, are reviewed with a particular focus on superconductor-insulator-superconductor (SIS) junctions formed by a break-junction method. The collective tunneling literature reveals two distinct energy scales, a large gap, Delta_L~7.2 meV, close to the expected BCS value, and a small gap, Delta_S~2.4 meV. The SIS break j

T. B. Humensky, R. Alley, A. Brachmann, M. J. Browne

SLAC E-158 is an experiment designed to make the first measurement of parity violation in Moller scattering. E-158 will measure the right-left cross-section asymmetry, A_LR^Moller, in the elastic scattering of a 45-GeV polarized electron beam off unpolarized electrons in a liquid hydrogen target. E-158 plans to measure the expected Standard Model asymmetry o

Sadhan K. Adhikari, Paulsamy Muruganandam

Using the mean-field time-dependent Gross-Pitaevskii equation we study the formation of a repulsive Bose-Einstein condensate on a combined optical and harmonic traps in two and three dimensions and subsequent generation of the interference pattern upon the removal of the combined traps as in the experiment by Greiner {\it et al.} [Nature (London) {\bf 415},

F. Vazquez, P. L. Krapivsky, S. Redner

We study opinion formation in a population that consists of leftists, centrists, and rightist. In an interaction between neighboring agents, a centrist and a leftist can become both centrists or leftists (and similarly for a centrist and a rightist). In contrast, leftists and rightists do not affect each other. The initial density of centrists rho_0 controls

Abha Dev, J. S. Alcaniz, Deepak Jain

A combination of recent observational results has given rise to what is currently known as the dark energy problem. Although several possible candidates have been extensively discussed in the literature to date the nature of this dark energy component is not well understood at present. In this paper we investigate some cosmological implications of another da

B. Ercolano, M. J. Barlow, P. J. Storey, X. -W. Liu

The study of photoionized environments is fundamental to many astrophysical problems. Up to the present most photoionization codes have numerically solved the equations of radiative transfer by making the extreme simplifying assumption of spherical symmetry. Unfortunately very few real astronomical nebulae satisfy this requirement. To remedy these shortcomin

G. Cynolter

We investigate coupled gravity and a bulk scalar field on a slice of AdS_5 bulk with special BPS branes at the two ends. With the special scalar potentials on the branes the scalar field does not stabilize the size of the orbifold. With a careful treatment of the general coordinate invariance the complete tensor-scalar spectrum is presented. There are two ma

V. Elias, D. G. C. McKeon

We examine two restructurings of the series relationship between the bare and renormalized coupling constant in dimensional regularization. In one of these restructurings, we are able to demonstrate via all-orders summation of leading and successive epsilon = 0 (dimensionality = 4) poles that the bare coupling vanishes in the dimension-4 limit.

A. J. King, M. Rowan-Robinson

In order to improve the fit to the optical counts, the multi-wavelength source count model of Rowan-Robinson (2001) is improved in two ways. First, density evolution is incorporated to correspond to the mergers in hierarchical models of galaxy formation. Secondly, the evolution of dust opacity is taken into account. The luminosity and density evolution param

B. C. Clark, S. Hama, L. J. Kerr

A new method for extracting neutron densities from intermediate energy elastic proton-nucleus scattering observables uses a global Dirac phenomenological (DP) approach based on the Relativistic Impulse Approximation (RIA). Data sets for Ca40, Ca48 and Pb208 in the energy range from 500 MeV to 1040 MeV are considered. The global fits are successful in reprodu

Toni Mateos, Josep M. Pons, Pere Talavera

We construct the noncommutative deformation of the Maldacena-Nunez supergravity solution. The background describes a bound state of D5-D3 branes wrapping an S^2 inside a Calabi-Yau three-fold, and in the presence of a magnetic B-field. The dual field theory in the IR is a N=1 U(N) SYM theory with spatial noncommutativity. We show that, under certain conditio

T. M. Aliev, O. Ozcan, M. Savci

We study the possibility of detecting noncommutative QED through neutral Higgs boson pair production at (gamma--gamma) collider. This is based on the assumption that H^0 interacts directly with photon as suggested by symmetry considerations. The sensitivity of the cross-section to the noncommutative scale (Lambda_{NC}) and Higgs mass is investigated.

D. X. Wang, K. Xiao, W. H. Lei

Evolution characteristics of a Kerr black hole (BH) are investigated by considering coexistence of disc accretion with the Blandford-Znajek process (the BZ process). (i) The rate of extracting energy from the rotating BH in the BZ process and that in MC process are expressed by a unified formula, which is derived by using an improved equivalent cicuit. (ii)

D. La-Orauttapong, J. Toulouse, Z. -G. Ye, W. Chen

Neutron elastic diffuse scattering experiments performed on Pb(Zn1/3Nb2/3)O3 (PZN) and on its solid solution with PbTiO3(PT), known as PZN-xPT, with x=4.5% and 9% around many reflections show that diffuse scattering is observed around reflections with mixed indices in the transverse and diagonal directions only. From the width of the diffuse scattering peak

Andrzej A. Zdziarski, Piotr Lubinski, Marat Gilfanov, Mike Revnivtsev

We study correlations betwen X-ray spectral index, strength of Compton reflection, and X-ray and radio fluxes in accreting black holes (Seyferts and black-hole binaries). We critically evaluate the evidence for the correlation of the X-ray spectral index with the strength of Compton reflection and consider in detail statistical and systematic effects that ca

Matteo Cacciari, Gennaro Corcella, Alexander D. Mitov

We study soft-gluon radiation in top quark decay within the framework of perturbative fragmentation functions. We present results for the b-quark energy distribution, accounting for soft-gluon resummation in both the MSbar coefficient function and in the initial condition of the perturbative fragmentation function. The results show remarkable improvement and

S. Kumano

The NuTeV collaboration reported anomalously large weak mixing angle sin^2 theta_W in comparison with the standard model prediction. Neutrino and antineutrino charged- and neutral-current events are analyzed for extracting sin^2 theta_W. Although the Paschos-Wolfenstein relation is not directly used in the analysis, it plays an important role in the determin

H. Kimura, M. Kofu, Y. Matsumoto, K. Hirota

Low-energy spin excitations of La1.85Sr0.15Cu1-yZnyO4 were studied by neutron scattering. In y=0.004, the incommensurate magnetic peaks show a well defined ``spin gap&#39;&#39; below Tc. The magnetic signals at omega=3 meV decrease below Tc=27 K for y=0.008, also suggesting the gap opening. At lower temperatures, however, the signal increases again, implying

H. Fujii

The momentum diffusion effect of the quark pair due to the multiple scattering in a nuclear medium is studied to explain the observed J/psi yields in SPS experiments. The resulting suppression is found to be insufficient to reproduce the J/psi yield in Pb-Pb collisions at SPS energy.

Yuji Sugawara

We calculate the thermal partition function of DLCQ superstring on the maximally supersymmetric pp-wave background, which is realized as the Penrose limit of orbifolded $AdS_5\times S^5$ and known to be dual to the $\mathcal{N}=2$ ``large&#39;&#39; quiver gauge theory as shown by S. Mukhi, M. Rangamani and E. Verlinde, hep-th/0204147. Making use of the path-

A. L. Pokrovsky, A. L. Efros

We argue that the widely spread opinion that the left-handed media (LHM) are characterized by a negative refractive index $n_-$ is misleading. Since n does not enter into Maxwell&#39;s equations and boundary conditions, any medium may be described by both positive n and negative $n_-=-n$. Two thermodynamic inequalities are presented, that make a difference b

Sze Kui Ng

It is shown that a photon with a specific frequency can be identified with the Dirac magnetic monopole. When a Dirac-Wilson line forms a Dirac-Wilson loop, it is a photon. This loop model of photon is exactly solvable. From the winding numbers of this loop-form of photon, we derive the quantization properties of energy and electric charge. A new QED theory i

James B. Hartle

The predictions of the Bohmian and the decoherent (or consistent) histories formulations of the quantum mechanics of a closed system are compared for histories -- sequences of alternatives at a series of times. For certain kinds of histories, Bohmian mechanics and decoherent histories may both be formulated in the same mathematical framework within which the

Mario J. Pinheiro

From the principle of maximum entropy for a closed system in thermal equilibrium, for the first instance a clear relation is shown to exist between total entropy S (in terms of arrangements of particles) and the classical expression for the force acting on a particle in a rotating frame. We determine relationships between arrangement of particles and force i

Bjoern Naundorf, Jan A. Freund

Detection and location of moving prey utilizing electrosense or mechanosense is a strategy commonly followed by animals which cannot rely on visual sense or hearing. In this article we consider the possibility to detect the source of a localized stimulus that travels along a chain of detectors at constant speed. The detectors are autonomous oscillators whose

Reginald T. Cahill

So far proposed quantum computers use fragile and environmentally sensitive natural quantum systems. Here we explore the new notion that synthetic quantum systems suitable for quantum computation may be fabricated from smart nanostructures using topological excitations of a stochastic neural-type network that can mimic natural quantum systems. These developm

Monique Signore, Denis Puy

Over the last decade, cosmological observations have attained a level of precision which allows for detailed comparison with theoretical predictions. In this paper, we briefly review some studies of the current and prospected constraints imposed by measurements of the cosmic microwave background radiation, of the mass and of the expansion of the Universe.

V. G. Gueorguiev, J. P. Draayer

A one-dimensional harmonic oscillator in a box is used to introduce the oblique-basis concept. The method is extended to the nuclear shell model by combining traditional spherical states, which yield a diagonal representation of the usual single-particle interaction, with collective configurations that track deformation. An application to 24Mg, using the rea

C. Garcia-Recio, J. Nieves, E. Ruiz Arriola, M. Vicente Vacas

The $s-$wave meson-baryon scattering amplitude is analyzed for the strangeness $S=-1$ and isospin I=0 sector in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry. Four two-body channels have been considered: $\bar K N$, $πΣ$, $ηΛ$, $ K Ξ$. The needed two particle irreducible matrix amplitude is taken from lowest order Chiral Perturbati

S. Schneider, J. Haidenbauer, C. Hanhart, J. A. Niskanen

We study pion absorption on 3He employing trinucleon wave functions calculated from modern realistic NN interactions (Paris, CD Bonn). Even though the use of the new wave functions leads to a significant improvement over older calculations with regard to both cross section and polarization data, there are hints that polarization data with quasifree kinematic

Andreas Schmitt, Qun Wang, Dirk H. Rischke

We study color superconductivity with $N_f=1,2,$ and 3 massless flavors of quarks. We present a general formalism to derive and solve the gap equations for condensation in the even-parity channel. This formalism shows that the leading-order contribution to the gap equation is unique for all color superconductors studied here, and that differences arise solel

Dieter Drechsel

The main features of the resonance structure of the nucleon are discussed, particular with regard to the helicity dependence of real and virtual photoabsorption. The dependence of the partial cross sections on both the resonance helicity amplitudes and the electromagnetic multipoles is outlined. The general structure of the Compton tensor is reviewed and app

L. V. Fil&#39;kov

A searche for supernarrow dibaryons (SND) and exotic baryons with small masses is reviewed. As a result of the study of the reaction pd->p+pX_1, three narrow peaks at M_{pX_1}=1904, 1926, and 1942 MeV have been observed. The analysis of the angular distributions of the protons from the decay of the pX_1 states showed that the peaks found can be explained as

Victor M. Perez-Garcia, Vadym Vekslerchik

We study a new class of vector solitons in trapped Nonlinear Schrodinger systems modelling the dynamics of coupled light beams in GRIN Kerr media and atomic mixtures in Bose-Einstein condensates. These solitons exist for different spatial dimensions, their existence is studied by means of a systematic mathematical technique and the analysis is made for inhom

V. G. Gueorguiev, A. I. Georgieva, P. P. Raychev, R. P. Roussev

A natural embedding $A_{m-1}\oplus A_{n-1}\subset A_{mn-1}$ for the corresponding quantum algebras is constructed through the appropriate comultiplication on the generators of each of the $A_{m-1}$ and $A_{n-1}$ algebras. The above embedding is proved in their $q$-boson realization by means of the isomorphism between the $\mathcal{A}_q^{-}$ (mn)$\sim {\otime

Anurag K. Singh

We show that the property of F-regularity does not deform, and thereby settle this longstanding open question in the theory of tight closure. Specifically, we construct a three dimensional domain R which is not F-regular (or even F-pure), but has a quotient R/tR which is F-regular. Similar examples are also constructed over fields of characteristic zero. Our

Anurag K. Singh

Hochster and Huneke showed that the property of F-regularity deforms for Gorenstein rings, i.e., if (R,m) is a Gorenstein local ring such that R/tR is F-regular for some nonzerodivisor t in m, then R is F-regular. This result was later extended to the case of Q-Gorenstein rings by Smith (for rings of characteristic zero) and Aberbach, Katzman, and MacCrimmon

William Fulton

Answering a question raised by S. Friedland, we show that the possible eigenvalues of Hermitian matrices (or compact operators) A, B, and C with C <= A + B are given by the same inequalities as in Klyachko&#39;s theorem for the case where C = A + B, except that the equality corresponding to tr(C) = tr(A) + tr(B) is replaced by the inequality corresponding to

Anurag K. Singh

In the ring R=K[X,Y,Z]/(X^3+Y^3+Z^3), where K is a field of prime characteristic p other than 3, determining the tight closure of the ideal (X^2, Y^2, Z^2)R had existed as a classic example of the difficulty involved in tight closure computations. We settle this question, compute the Frobenius closure of this ideal, and generalize these results to the diagon

Anurag K. Singh

We demonstrate that the ring of invariants for the natural action of a subgroup G of GL_n(F_q) on a polynomial ring R=K[X_1,...,X_n] need not be F-pure. In these examples G is the symplectic group over a finite field, and the invariant subrings are always complete intersections by the work of Carlisle and Kropholler. These examples are of special interest fr

Anurag K. Singh

An equidimensional local ring is F-rational if and only if one ideal generated by a system of parameters is tightly closed. The question of whether a non-equidimensional local ring can have a tightly closed ideal generated by a system of parameters has been a long-standing open problem, and for certain classes of non-equidimensional rings we prove that this

Jonathan Brundan

This is a companion article to my papers on Kazhdan-Lusztig polynomials and character formulae for the Lie superalgebras gl(m|n) (much revised!) and q(n). The goal is to develop the general theory of tilting modules for Lie superalgebras, working in a general graded setting very similar to work of Soergel (Character formulae for tilting modules over Kac-Mood

S. V. Ivanov

A group $G$ given by a presentation $G = < \mathcal A \| \mathcal R >$ is called weakly finitely presented if every finitely generated subgroup of $G$, generated by (images of) some words in $\mathcal A^{\pm 1}$, is naturally isomorphic to the subgroup of a group $G_0 = < \mathcal A_0 \| \mathcal R_0>$, where $\mathcal A_0 \subseteq \mathcal A$, $\mathcal R_

Laurent Berger

The purpose of this article is to give a proof of the $C_{EP,F}(V)$ conjecture for some semi-stable representations and of the $δ_{\Zp}(V)$ conjecture for some crystalline representations. There are two major ingredients: first, the computation of Tamagawa numbers using a variation on results of Fontaine-Laffaille and of Bloch-Kato, and second some continuit

Jailton C. Ferreira

It is shown that if every odd integer $n > 5$ is the sum of three primes, then every even integer $n > 2$ is the sum of two primes. A conditional proof of Goldbach&#39;s conjecture, based on Cramér&#39;s conjecture, is presented. Theoretical and experimental results available on Goldbach&#39;s conjecture allow that a less restrictive conjecture than Cramér&#

Boris Solomyak, Hui Xu

We consider the &#34;Mandelbrot set&#34; $M$ for pairs of complex linear maps, introduced by Barnsley and Harrington in 1985 and studied by Bousch, Bandt and others. It is defined as the set of parameters $λ$ in the unit disk such that the attractor $A_λ$ of the IFS $\{λz-1, λz+1\}$ is connected. We show that a non-trivial portion of $M$ near the imaginary a

Darren Glass

In this paper we suppose G is a finite group acting tamely on a regular projective curve X over Z and V is an orthogonal representation of G of dimension 0 and trivial determinant. Our main result determines the sign of the $ε$-constant $ε(X/G,V)$ in terms of data associated to the archimedean place and to the crossing points of irreducible components of fin

Astrid Reifegerste

Egge and Mansour have recently studied permutations which avoid 1243 and 2143 regarding the occurrence of certain additional patterns. Some of the open questions related to their work can easily be answered by using permutation diagrams. Like for 132-avoiding permutations the diagram approach gives insights into the structure of {1243,2143}-avoiding permutat

Bruce Solomon

The projection of a compact oriented submanifold M^{n-1} in R^{n+1} on a hyperplane P^{n} can fail to bound any region in P. We call this ``projecting to zero.&#39;&#39; Example: The equatorial S^1 in S^2 projects to zero in any plane containing the x_3-axis. Using currents to make this precise, we show: A lipschitz (homology) (n-1)-sphere embedded in a comp

R. M. Green

Let $A$ be an associative algebra with identity and with trace. We study the family of planar algebras on 1-boxes that arise from $A$ in the work of Jones, but with the added assumption that the labels on the 1-boxes come from a discrete hypergroup in the sense of Sunder. This construction equips the algebra $P_n^A$ with a canonical basis, $\BB_n^A$, which t

Asen L. Dontchev

We prove that if a mapping F:X to Y, where X and Y are Banach spaces, is metrically regular at x for y and its inverse F^{-1} is convex and closed valued locally around (x,y), then for any function G:X to Y with lip G(x)regF(x|y)) < 1, the mapping (F+G)^{-1} has a continuous local selection around (x, y+G(x)) which is also calm.

Timothy J. McLarnan, Gregory S. Warrington

For permutations x and w, let mu(x,w) be the coefficient of highest possible degree in the Kazhdan-Lusztig polynomial P_{x,w}. It is well-known that the coefficients mu(x,w) arise as the edge labels of certain graphs encoding the representations of S_n. The 0-1 Conjecture states that the mu(x,w) are either 0 or 1. We present two counterexamples to this conje

Ekaterina Amerik

Let $X$ be a complex projective bundle. We prove that $X$ admits an endomorphism of degree $>1$ and commuting with the projection to the base, if and only if $X$ trivializes after a finite covering. When $X$ is the projectivization of a vector bundle $E$ of rank 2, we prove that it has an endomorphism of degree $>1$ on a general fiber only if $E$ splits afte

Sacha Blumen

We create Resthetikhin-Turaev topological invariants of closed orientable three-manifolds from the quantum supergroup U_q(osp(1|2n)) at certain even roots of unity. To construct the invariants we develop tensor product theorems for finite dimensional modules of U_q(osp(1|2n)) at roots of unity.

Kai Cieliebak, Dietmar A. Salamon

We derive a wall crossing formula for the symplectic vortex invariants of toric manifolds. As an application, we give a proof of Batyrev&#39;s formula for the quantum cohomology of a monotone toric manifold with minimal Chern number at least two.

Edward Swartz

There is a one-to-one correspondence between geometric lattices and the intersection lattices of arrangements of homotopy spheres. When the arrangements are essential and fully partitioned, Zaslavsky&#39;s enumeration of the cells of the arrangement still holds. An application of the theory shows that all minimal cellular resolutions of matroid Steiner ideal

Dimitrios I. Dais, Martin Henk

Based on Nakajima&#39;s Classification Theorem we describe the precise form of the binomial equations which determine toric locally complete intersection (&#34;l.c.i&#39;&#39;) singularities.

Gefry Barad

We compute the rank of the first homology group and we study the higher Betti numbers of the real points of the Deligne-Mumford-Knudsen compactification of stable n-pointed curves of genus 0,which coincides with the Chow quotient (RP^1)^n//PGL(2,R)(after Kapranov).

Jonathan Brundan

The problem of computing the characters of the finite dimensional irreducible representations of the Lie superalgebra $\mathfrak{gl}(m|n)$ over $\C$ was solved a few years ago by V. Serganova. In this article, we present an entirely different approach. One consequence is a direct and elementary proof of a conjecture made by van der Jeugt and Zhang for the co

M. Cataldo

In three-dimensional Einstein-Maxwell gravity the electrostatic Banados-Teitelboim-Zanelli solution and the magnetostatic Hirschmann-Welch solution are connected by a duality mapping. Here we point out that a similar duality mapping exists among circularly symmetric electrostatic and magnetostatic spacetimes, and electric and magnetic stationary solutions, f

Christiaan Hofman, Jae-Suk Park

We study topological open membranes of BF type in a manifest BV formalism. Our main interest is the effect of the bulk deformations on the algebra of boundary operators. This forms a homotopy Lie algebra, which can be understood in terms of a closed string field theory. The simplest models are associated to quasi-Lie bialgebras and are of Chern-Simons type.

Giampiero Esposito, Giuseppe Marmo, Cosimo Stornaiolo

Peierls brackets are part of the space-time approach to quantum field theory, and provide a Poisson bracket which, being defined for pairs of observables which are group invariant, is group invariant by construction. It is therefore well suited for combining the use of Poisson brackets and the full diffeomorphism group in general relativity. The present pape

Shun-ichi Yamaguchi

We study four-point correlation functions with logarithmic behaviour in Liouville field theory on a sphere, which consist of one kind of the local operators. We study them as non-integrated correlation functions of the gravitational sector of two-dimensional quantum gravity coupled to an ordinary conformal field theory in the conformal gauge. We also examine

M. Rausch de Traubenberg

F-Lie algebras are natural generalisations of Lie algebras (F=1) and Lie superalgebras (F=2). We give finite dimensional examples of F-Lie algebras obtained by an inductive process from Lie algebras and Lie superalgebras. Matrix realizations of the $F-$Lie algebras constructed in this way from osp(2|m) are given. We obtain a non-trivial extension of the Poin

G. Toledo Sanchez

The result by Burnett-Kroll (BK) states that for radiative decays the interference of ${\cal O}(ω^{-1})$ in the photon energy $ω$, vanishes after sum over polarizations of the involved particles. Using radiative decays of vector mesons we show that if the vector meson is polarized the ${\cal O}(ω^{-1})$ terms are null only for the canonical value of the magn

Benjamin Grinstein, Dan Pirjol

It has been proposed to determine the CKM matrix element |V_ub| in a model-independent way from a combination of rare and semileptonic B and D decays near the zero recoil point. An essential ingredient in such a determination is a heavy quark symmetry relation connecting the form-factors appearing in B -> K* e+e- to semileptonic form factors relevant for B -

S. Moretti

I review all the new features of the HERWIG event generator which are relevant to Linear Collider (LC) physics starting from version 6.1

A. Dedes, J. Ellis, M. Raidal

We study the rates allowed for the Higgs-mediated decays $B_{s,d}^0\toμτ, eτ$ and $τ\to μμμ, eμμ$ in supersymmetric seesaw models, assuming that the only source of lepton flavour violation (LFV) is the renormalization of soft supersymmetry-breaking terms due to off-diagonal singlet-neutrino Yukawa interactions. These decays are strongly correlated with, and

B. Nicolescu, J. R. Cudell, V. V. Ezhela, P. Gauron

We consider several classes of analytic parametrizations of hadronic scattering amplitudes, and compare their predictions to all available forward data in hadron-hadron, gamma-p and gamma-gamma reactions. Although these parametrizations are very close for SQRTs larger than 9 GeV, it turns out that they differ markedly at low energy, where a universal Pomeron

Irit Maor, Ram Brustein

We show that various scalar field models of dark energy predict degenerate luminosity distance history of the Universe and thus cannot be distinguished by supernovae measurements alone. In particular, models with a vanishing cosmological constant (the value of the potential at its minimum) are degenerate with models with a positive or negative cosmological c

W. Bernreuther, A. Brandenburg, Z. G. Si, P. Uwer

We present results at NLO QCD for hadronic production and decay of top quark pairs, taking into account t tbar spin correlations.

qing wang, Yu-Ping Kuang, Hua Yang, Qin Lu

Based on a previous study of deriving the chiral Lagrangian (CL) from QCD, we illustrate the main feature of QCD predictions for the CL coefficients (CLC) in certain approximations. We first show that, in the large-N(c) limit, the anomaly part contributions to the CLC are exactly cancelled by certain terms in the normal part contributions (NPC), so that the

P. Z. Skands

In supersymmetric scenarios with broken R-parity, baryon number violating sparticle decays are possible. We report on the development of a framework allowing detailed studies with special attention given to the hadronization phase. In our model, implemented in the Pythia event generator, the baryon number violating vertex is associated with the appearance of

K. Werner, H. J. Drescher, S. Ostapchenko, T. Pierog

The interpretation of experimental results at RHIC and in the future also at LHC requires very reliable and realistic models. Considerable effort has been devoted to the development of such models during the past decade, many of them being heavily used in order to analyze data. There are, however, serious inconsistencies in the above-mentioned approaches. In

N. V. Mikheev, E. N. Narynskaya

The neutrino-electron scattering in a dense degenerate magnetized plasma under the conditions $μ^2 > 2eB \gg μE$ is investigated. The volume density of the neutrino energy and momentum losses due to this process are calculated. The results we have obtained demonstrate that plasma in the presence of an external magnetic field is more transparent for neutrino

Yong-Yeon Keum

We look at two methods to determine the weak phases $ϕ_2$ and $ϕ_3$ from $B \to ππ$ and $Kπ$ decays within the perturbative QCD approach. We obtain quite interesting bounds on $ϕ_2$ and $ϕ_3$ from recent experimental measurements in asymmetric B-factory: $55^o \leq ϕ_2 \leq 100^o$ and $51^o \leq ϕ_3 \leq 129^o$. Specially we predict the possibility of large

Jun Tabei, Hiroshi Hotta

Constraints on the common trilinear coupling constant $A_{0}$ are obtained in the minimal supergravity model. $A_{0}$ is usually given at GUT scale $M_{X}$ by-hand, and has been regarded as one of the five arbitrary parameters in this model. However, $B(M_{Z})$ as the common bilinear coupling constant $B$ at the electroweak scale $M_{Z} \simeq 91$(GeV) is fi

Konstantinos Orginos, RBC Collaboration

We present the status of our calculation of the first few moments of the nucleon structure functions. Our calculations are done using domain wall fermions in the quenched approximation with the DBW2 gauge action at 1.3GeV inverse lattice spacing.

D. Becirevic, Ph. Boucaud, V. Gimenez, C. -J. D. Lin

We present results of several numerical studies with Wilson fermions relevant for kaon physics. We compute the B_K parameter by using two different methods and extrapolate to the continuum limit. Our preliminary result is B_K(2 GeV)=0.66(7). Delta I=3/2 K->pi pi matrix elements are obtained by using the next-to-leading order expressions derived in chiral per

Kerryann M. Foley, G. Peter Lepage

We derive the continuum and lattice tree-level moving NRQCD (mNRQCD) through order 1/m^2. mNRQCD is a generalization of NRQCD for dealing with hadrons with nonzero velocity u_mu. The quark&#39;s total momentum is written as P^mu=Mu^mu+k^mu where k^mu << Mu^mu is discretized and Mu^mu is treated exactly. Radiative corrections to couplings on the lattice are d