September 2002 arXiv papers — page 17

P. M. Koch, Ph. Jetzer, D. Puy

We study the influence of converging cooling flow bulk motions on the Sunyaev-Zel'dovich (SZ) effect. To that purpose we derive a modified Kompaneets equation which takes into account the contribution of the accelerated electron media of the cooling flow inside the cluster frame. The additional term is different from the usual kinematic SZ-effect, which

J. A. Baldwin, G. J. Ferland, K. T. Korista, F. Hamann

We show that the mass of ionized gas in the Broad Line Regions (BLRs) of luminous QSOs is at least several hundred Msun, and probably of order 10^3-10^4 M_sun. BLR mass estimates in several existing textbooks suggest lower values, but pertain to much less luminous Seyfert galaxies or include only a small fraction of the ionized/emitting volume of the BLR. Th

M. A. Barstow, L. Binette, N. Brosch, F-Z. Cheng

The World Space Observatory is an unconventional space project proceeding via distributed studies. The present design, verified for feasibilty, consists of a 1.7-meter telescope operating at the second Largangian point of the Earth-Sun system. The focal plane instruments consist of three UV spectrometers covering the spectral band from Lyman alpha to the atm

T. Tamura, J. S. Kaastra, J. A. M. Bleeker, J. R. Peterson

Based on XMM-Newton observations of a sample of galaxy clusters, we have measured the elemental abundances (mainly O, Si, S, and Fe) and their spatial distributions in the intracluster medium (ICM). In the outer region of the ICM, observations of the O:Si:S:Fe ratio are consistent with the solar value, suggesting that the metals in the ICM were produced by a

F. D'Antona, V. Caloi, J. Montalban, P. Ventura

It is becoming clear that `self--pollution' by the ejecta of massive asymptotic giant branch stars has an important role in the early chemical evolution of globular cluster stars, producing CNO abundance spreads which are observed also at the surface of unevolved stars. Considering that the ejecta which are CNO processed must also be helium enriched, we

Francis Bernardeau, Jean-Philippe Uzan

We construct explicit models of multi-field inflation in which the primordial metric fluctuations do not necessarily obey Gaussian statistics. These models are realizations of mechanisms in which non-Gaussianity is first generated by a light scalar field and then transferred into curvature fluctuations. The probability distribution functions of the metric pe

E. Babichev, V. Dokuchaev

We derived expressions for energy, momentum and angular momentum losses due to gravitational and electromagnetic radiation from the closed superconducting chiral cosmic strings of arbitrary form. The expressions for corresponding radiation rates into the unit solid angle have the form of four-dimensional integrals. In the special case of piece-wise linear st

S. A. Levshakov, I. I. Agafonova, S. D'Odorico, A. M. Wolfe

Detailed Monte Carlo Inversion analysis of the spectral lines from three Lyman limit systems (LLS) [N(HI) > 10^{17} cm^-2] and nine lower N(HI) systems [2 10^{14} < N(HI) < 2 10^{16} cm^-2] observed in the VLT/UVES spectra of Q0347-3819 (in the range 2.21 <= z <= 3.14) and of APM BR J0307-4945 (at z = 4.21 and 4.81) is presented. Combined with the results fr

Marie M. Machacek, Greg L. Bryan, Tom Abel

We use three dimensional hydrodynamic simulations to investigate the effects of a soft X-ray background, that could have been produced by an early generation of mini-quasars, on the subsequent cooling and collapse of high redshift pregalactic clouds. The simulations use an Eulerian adaptive mesh refinement technique with initial conditions drawn from a flat

S. Frandsen, F. Carrier, C. Aerts, D. Stello

We report the firm discovery of solar-like oscillations in a giant star. We monitored the star xi Hya (G7III) continuously during one month with the CORALIE spectrograph attached to the 1.2m Swiss Euler telescope. The 433 high-precision radial-velocity measurements clearly reveal multiple oscillation frequencies in the range 50 - 130 uHz, corresponding to pe

V. I. Dokuchaev, Yu. N. Eroshenko

We argue that the observed correlations between central black holes masses M_{BH} and galactic bulge velocity dispersions σ_e in the form M_{BH}\proptoσ_e^4 may witness on the pregalactic origin of massive black holes. Primordial black holes would be the centers for growing protogalaxies which experienced multiple mergers with ordinary galaxies. This process

C. P. Dullemond

In this paper the two-dimensional structure of protoplanetary disks around Herbig Ae/Be stars is studied. This is done by constructing a self-consistent model based on 2-D radiative transfer coupled to the equation of vertical hydrostatics. As a simplifying assumption a grey opacity is used. It is found that the disk can adopt four different structures, depe

T. Kato, M. Uemura, R. Ishioka, J. Pietz

We observed the 2001 November superoutburst of CC Cnc. This observation makes the first detailed coverage of a superoutburst of this object. The best-determined mean superhump period is 0.075518 +/- 0.000018 d, which is 2.7% longer than the reported orbital period. This fractional superhump excess is a quite typical value for a normal SU UMa-type dwarf nova,

Emma Ryan-Weber, Rachel Webster, Kenji Bekki

We report the discovery of a new HI ring around the S0 galaxy NGC 1533. The ring orbits at a radius of 35 kpc, well outside the optical extent of the galaxy. We have conducted N-body/SPH numerical simulations to show this HI ring could be the merger remnant of a tidally destroyed galaxy. We find no optical component associated with the HI ring. However, obse

Yasufumi Kojima, Koh-ichi Sakata

The frequencies and damping times due to gravitational radiation are calculated for self-bound quark star models. The results are compared with those for neutron star models. They are markedly contrasted in less relativistic cases. The distinction derived here from a simple model of quark stars may be relevant to the future theoretical and observational stud

Nicolas A. Pereyra, Timothy R. Kallman

We present time-dependent numerical hydrodynamic models of line-driven accretion disk winds in cataclysmic variable systems and calculate wind mass-loss rates and terminal velocities. The models are 2.5-dimensional, include an energy balance condition with radiative heating and cooling processes, and includes local ionization equilibrium introducing time dep

Stanimir Metchev, Lynne Hillenbrand, Russel White

From adaptive optics observations with the Palomar 5-meter telescope we place upper limits on the masses of any planetary companions located between ~30-230 AU away from Vega, where our data are sensitive to depths ranging from H=12.5 mag to H=19.0 mag fainter than Vega itself. Our observations cover a plus-shaped area with two 25&#34;x57&#34; elements, excl

Elizabeth Barton Gillespie, Margaret J. Geller, Scott J. Kenyon

Galaxy-galaxy interactions rearrange the baryons in galaxies and trigger substantial star formation; the aggregate effects of these interactions on the evolutionary histories of galaxies in the Universe are poorly understood. We combine B and R-band photometry and optical spectroscopy to estimate the strengths and timescales of bursts of triggered star forma

C. R. Contaldi, J. R. Bond, D. Pogosyan, B. S. Mason

We derive cosmological parameters from the CBI measurements of the Cosmic Microwave Background (CMB) angular power spectrum. Our results provide an independent confirmation of the standard $Ω_{\rm tot}=1$ $Λ$CDM model within the adiabatic, inflationary paradigm. Above $\ell=2000$ the observations show evidence of power in excess of that expected in the stand

Matthias Burkardt

Generalized parton distributions (GPDs) with purely transverse momentum transfer can be interpreted as Fourier transforms of the distribution of partons in impact parameter space. The helicity-flip GPD $E(x,0,-\Dps)$ is related to the distortion of parton distribution functions in impact parameter space if the target is not a helicity eigenstate, but has som

Joris Gerssen, Roeland P. van der Marel, Karl Gebhardt, Puragra Guhathakurta

We analyze HST/STIS spectra (see Paper I) of the central region of the dense globular cluster M15. We infer the velocities of 64 individual stars, two-thirds of which have their velocity measured for the first time. This triples the number of stars with measured velocities in the central 1 arcsec of M15 and doubles the number in the central 2 arcsec. Combine

Jairo Sinova, C. B. Hanna, A. H. MacDonald

We demonstrate a direct connection between the density profile of a system of ultra-cold trapped bosonic particles in the rapid-rotation limit and its condensate fraction. This connection can be used to probe the crossover from condensed vortex-lattice states to uncondensed quantum fluid states that occurs in rapidly rotating boson systems as the particle de

Gang Liu

The purpose of this paper is to derive the dynamical equations for the period vectors of a periodic system under constant external stress. The explicit starting point is Newton&#39;s second law applied to halves of the system. Later statistics over indistinguishable translated states and forces associated with transport of momentum are applied to the resulti

B. C. Tiburzi, G. A. Miller

We use a two-body, light-cone pion wave function (which vanishes when one of the constituents carries all of the plus-momentum) to construct a double distribution. We show that the resulting generalized parton distribution has incorrect behavior at the crossover between kinematic regions. Furthermore the positivity constraints are not respected. On the other

I. Rogachevskii, N. Kleeorin

An effect of sheared large-scale motions on a mean electromotive force in a nonrotating turbulent flow of a conducting fluid is studied. It is demonstrated that in a homogeneous divergence-free turbulent flow the alpha-effect does not exist, however a mean magnetic field can be generated even in a nonrotating turbulence with an imposed mean velocity shear du

Walter D. Goldberger, Yasunori Nomura, David R. Smith

We construct a realistic theory of grand unification in AdS_5 truncated by branes, in which the unified gauge symmetry is broken by boundary conditions and the electroweak scale is generated by the AdS warp factor. We show that the theory preserves the successful gauge coupling unification of the 4D MSSM at leading-logarithmic level. Kaluza-Klein (KK) towers

Bo He, T. P. Cheng, Ling-Fong Li

When mu-e-gamma (or tau-mu-gamma) loop involves a vector boson, the amplitude is suppressed by more than two powers of heavy particle masses. However we show that the scalar boson loop diagrams are much less damped. Particularly, the loop amplitude in which the intermediate fermion and scalar boson have comparable masses is as large as possible, as allowed b

Rei Inoue

Based on the work by Smirnov and Zeitlin, we study a simple realization of the matrix construction of the affine Jacobi varieties. We find that the realization is given by a classical integrable model, the extended Lotka-Volterra lattice. We investigate the integrable structure of the representative for the gauge equivalence class of matrices, which is isomo

Y. Kopelevich, V. V. Lemanov, S. Moehlecke, J. H. S. Torres

Measurements of the basal-plane resistivity rho_a(T,H) performed on highly oriented pyrolitic graphite, with magnetic field H parallel to the c-axis in the temperature interval 2 - 300 K and fields up to 8 T, provide evidence for the occurrence of both field - induced and zero-field superconducting instabilities. Additionally, magnetization M(T,H) measuremen

Hagen Kleinert, Flavio S. Nogueira, Asle Sudbo

We point out that the permanent confinement in a compact 2+1-dimensional U(1) Abelian Higgs model is destroyed by matter fields in the fundamental representation. The deconfinement transition is Kosterlitz-Thouless like. The dual theory is shown to describe a three-dimensional gas of point charges with logarithmic interactions which arises from an anomalous

Carl H. Albright, S. M. Barr

It has been shown recently that the problem of rapid proton decay induced by dimension five operators arising from the exchange of colored Higgsinos can be simply avoided in grand unified models where a fifth spatial dimension is compactified on an orbifold. Here we demonstrate that this idea can be used to solve the Higgsino-mediated proton decay problem in

Marats Golovkins, Maksim Kravtsev

To study relationship between quantum finite automata and probabilistic finite automata, we introduce a notion of probabilistic reversible automata (PRA, or doubly stochastic automata). We find that there is a strong relationship between different possible models of PRA and corresponding models of quantum finite automata. We also propose a classification of

Martin Sombra

We compute the successive minima of the projective toric variety $X_\cA$ associated to a finite set $ \cA \subset \Z^n$. As a consequence of this computation and of the results of S.-W. Zhang on the distribution of small points, we derive estimates for the height of the subvariety $X_\cA$ and of the $\cA$-resultant. These estimates allow us to obtain an arit

Eckhard Meinrenken

Let $G$ be a compact, simply connected simple Lie group. We give a construction of an equivariant gerbe with connection on $G$, with equivariant 3-curvature representing a generator of $H^3_G(G,\Z)$. Technical tools developed in this context include a gluing construction for gerbes and a theory of equivariant bundle gerbes.

Ernest Ma

Given the experimental evidence for $ν_μ- ν_τ$ oscillations, the existence of lepton flavor violation in $τ$ decays is a theoretical certainty. In this brief review, I consider the connection between models of neutrino mass and the expected observability of some $τ$ decays.

B. Schlittgen, T. Wettig

Using the character expansion method, we generalize several well-known integrals over the unitary group to the case where general complex matrices appear in the integrand. These integrals are of interest in the theory of random matrices and may also find applications in lattice gauge theory.

Ryutaroh Matsumoto

We show how to convert a quantum stabilizer code to a one-way or two-way entanglement distillation protocol. The proposed conversion method is a generalization of those of Shor-Preskill and Nielsen-Chuang. The recurrence protocol and the quantum privacy amplification protocol are equivalent to the protocols converted from [[2,1]] stabilizer codes. We also gi

Hsiao-Ping Hsu, Vishal Mehra, Walter Nadler, Peter Grassberger

An improved version of the pruned-enriched-Rosenbluth method (PERM) is proposed and tested on finding lowest energy states in simple models of lattice heteropolymers. It is found to outperform not only the previous version of PERM, but also all other fully blind general purpose stochastic algorithms which have been employed on this problem. In many cases it

K. Capelle

A generating coordinate is introduced into the exchange-correlation functional of density-functional theory (DFT). The many-body wave function is represented as a superposition of Kohn-Sham (KS) Slater determinants arising from different values of the generating coordinate. This superposition is used to variationally calculate many-body energies and wave fun

Maulik K. Parikh, Ivo Savonije, Erik Verlinde

We propose that for every event in de Sitter space, there is a CPT-conjugate event at its antipode. Such an ``elliptic&#39;&#39; $Z_2$-identification of de Sitter space provides a concrete realization of observer complementarity: every observer has complete information. It is possible to define the analog of an S-matrix for quantum gravity in elliptic de Sit

Changhyun Ahn, Kyungsung Woo

The scalar potentials of the non-semi-simple CSO(p,8-p)(p=7,6,5) gaugings of N=8 supergravity are studied for critical points. The CSO(7,1) gauging has no G_2-invariant critical points, the CSO(6,2) gauging has three new SU(3)-invariant AdS critical points and the CSO(5,3) gauging has no SO(5)-invariant critical points. The scalar potential of CSO(6,2) gaugi

M. Bozovic, Z. Pajovic, Z. Radovic

We study coherent quantum transport through a superconducting film connected to normal-metal electrodes. Simple expressions for the differential conductance and the local density of states are obtained in the clean limit and for transparent interfaces. Quasiparticle interference causes periodic vanishing of the Andreev reflection at the energies of geometric

A. Cruz, L. A. Fernandez, S. Jimenez, J. J. Ruiz-Lorenzo

We study the fluctuation-dissipation relations for a three dimensional Ising spin glass in a magnetic field both in the high temperature phase as well as in the low temperature one. In the region of times simulated we have found that our results support a picture of the low temperature phase with broken replica symmetry, but a droplet behavior can not be com

Ji-Sheng Chen, Jia-Rong Li, Peng-Fei Zhuang

The dispersion relation of $ρ$ meson in both timelike and spacelike regimes in hot and dense nuclear medium is analyzed and compared with $σ$ meson based on the quantum hadrodynamics model. The pole and screening masses of $ρ$ and $σ$ are discussed. The behavior of screening mass of $ρ$ is different from that of $σ$ due to different Dirac- and Fermi-sea cont

R. A. Blythe, A. J. Bray

The problem of a diffusing particle moving among diffusing traps is analyzed in general space dimension d. We consider the case where the traps are initially randomly distributed in space, with uniform density rho, and derive upper and lower bounds for the probability Q(t) (averaged over all particle and trap trajectories) that the particle survives up to ti

C. Giunti, M. Tanimoto

We propose a scheme of lepton mixing in which the unitary matrix that diagonalizes the neutrino mass matrix is bimaximal and the deviation from bimaximal of the lepton mixing matrix is due to the unitary matrix that diagonalizes the charged-lepton mass matrix. This matrix is assumed to be hierarchical, like the quark mixing matrix. It is shown that in genera

Tadafumi Ohsaku

We investigate the relativistic model of superconductivity in (2+1)-dimension. We employ the massless Gross-Neveu model at finite temperature and density, to study the superconductivity and superconducting instability. Our investigation is related to the superconductivity in (2+1)-dimensional two-band systems like ${\rm MgB_{2}}$ or intercalated graphite.

John Schliemann

We study the correlation energy, the effective anisotropy parameter, and quantum fluctuations of the pseudospin magnetization in bilayer quantum Hall systems at total filling factor nu=1 by means of exact diagonalizations of the Hamiltonian in the spherical geometry. We compare exact diagonalization results for the ground state energy with finite-size Hartre

Francisco D. Mazzitelli, María J. Sánchez, Norberto N. Scoccola, Javier von Stecher

The Casimir interaction between two perfectly conducting, infinite, concentric cylinders is computed using a semiclassical approximation that takes into account families of classical periodic orbits that reflect off both cylinders. It is then compared with the exact result obtained by the mode-by-mode summation technique. We analyze the validity of the semic

L. You, X. X. Yi, X. H. Su

We propose a protocol for conditional quantum logic between two 4-state atoms inside a high Q optical cavity. The process detailed in this paper utilizes a direct 4-photon 2-atom resonant process and has the added advantage of commonly addressing the two atoms when they are inside the high Q optical cavity.

Hamidreza Simchi

The relations between Bell&#39;s inequality and quantum probability trees are explained against the background offered by the concept of a quantum probability tree built in others works. It is shown that f we use a concept of probability tree it will not be necessary we set aside the principle of separability and principle of locality.

Y. -J. Han, Y. -S. Zhang, G. -C. Guo

Due to the no-cloning theorem, the unknown quantum state can only be cloned approximately or exactly with some probability. There are two types of cloners: universal and state-dependent cloner. The optimal universal cloner has been found and could be viewed as a special state-dependent quantum cloner which has no information about the states. In this paper,

Jae-weon Lee, Chang Ho Kim, Eok Kyun Lee, Jaewan Kim

Identifying the Bolch sphere with the Riemann sphere(the extended complex plane), we obtain relations between single qubit unitary operations and Möbius transformations on the extended complex plane.

C. P. Achenbach, J. H. Cobb

A Monte Carlo simulation has been performed to track light rays in cylindrical fibres by ray optics. The trapping efficiencies for skew and meridional rays in active fibres and distributions of characteristic quantities for all trapped light rays have been calculated. The simulation provides new results for curved fibres, where the analytical expressions are

S. Bellucci, V. M. Biryukov, Yu. A. Chesnokov, V. Guidi

A particle beam of very small cross-section is useful in many accelerator applications including biological and medical ones. We show the capability of the channeling technique using a micron-sized structure on a surface of a single crystal, or using a nanotube, to produce beam of a cross-section down to 1 square micrometer (or nanometer). The channeled beam

Mark W. Paris

Basic theoretical issues relating to the response of confined relativistic particles are considered including the scaling of the response in spacelike and timelike regions of momentum transfer and the role of final state interactions. A simple single particle potential model incorporating relativity and linear confinement is solved exactly and its response i

V. E. Oberacker, A. S. Umar, E. Teran

We have developed a new Hartree-Fock-Bogoliubov (HFB) code which has been specifically designed to study ground state properties of nuclei near the neutron and proton drip lines. The unique feature of our code is that it takes into account the strong coupling to high-energy continuum states, up to an equivalent single-particle energy of 60 MeV. We solve the

L. Mornas, J. P. Suarez Curieses, J. Diaz Alonso

We explore the possible formation of ordered phases in neutron star matter. In the framework of a quantum hadrodynamics model where neutrons, protons and Lambda hyperons interact via the exchange of mesons, we compare the energy of the usually assumed uniform, liquid phase, to that of a configuration in which di-lambda pairs immersed in an uniform nucleon fl

Jong-Won Kim, Sang-Yoon Kim, Brian Hunt, Edward Ott

We consider the existence of robust strange nonchaotic attractors (SNA&#39;s) in a simple class of quasiperiodically forced systems. Rigorous results are presented demonstrating that the resulting attractors are strange in the sense that their box-counting dimension is N+1 while their information dimension is N. We also show how these properties are manifest

J. Main, G. Wunner, E. Atilgan, H. S. Taylor

In systems with few degrees of freedom modern quantum calculations are, in general, numerically more efficient than semiclassical methods. However, this situation can be reversed with increasing dimension of the problem. For a three-dimensional system, viz. the hyperbolic four-sphere scattering system, we demonstrate the superiority of semiclassical versus q

A. N. F. Aleixo, A. B. Balantekin, M. A. Candido Ribeiro

A decomposition of identity is given as a complex integral over the coherent states associated with a class of shape-invariant self-similar potentials. There is a remarkable connection between these coherent states and Ramanujan&#39;s integral extension of the beta function.

B. Bagchi, C. Quesne

Potential algebras are extended from Hermitian to non-Hermitian Hamiltonians and shown to provide an elegant method for studying the transition from real to complex eigenvalues for a class of non-Hermitian Hamiltonians associated with the complex Lie algebra A$_1$.

Sergei Konyagin, Izabella Laba

We consider two number-theoretic problems arising from Fuglede&#39;s spectral set conjecture: characterizing finite sets that tile integers, and finding polynomials with (0,1) coefficients whose roots have a certain multiplicative structure. We verify several special cases of the relevant conjectures; in particular, we find necessary and sufficient condition

William Fulton

We give an exposition of the theory of adjoints and conductors for curves on nonsingular surfaces, emphasizing the case of plane curves, for which the presentation is particularly elementary. This is closely related to Max Noether&#39;s ``AF+BG&#39;&#39; theorem, which is proved for curves with arbitrary multiple components.

Mu-Tao Wang

Let $M=Σ_1\times Σ_2$ be the product of two compact Riemannian manifolds of dimension $n\geq 2 $ and two, respectively. Let $Σ$ be the graph of a smooth map $f:Σ_1\mapsto Σ_2$, then $Σ$ is an $n$-dimensional submanifold of $M$. Let ${\frak G}$ be the Grassmannian bundle over $M$ whose fiber at each point is the set of all $n$-dimensional subspaces of the tan

Ioannis Kontoyiannis, Sean Meyn

Consider the partial sums {S_t} of a real-valued functional F(Phi(t)) of a Markov chain {Phi(t)} with values in a general state space. Assuming only that the Markov chain is geometrically ergodic and that the functional F is bounded, the following conclusions are obtained: 1. Spectral theory: Well-behaved solutions can be constructed for the ``multiplicative

Craig Huneke

This paper is based on a talk given by the author in October, 1997 at a conference at Columbia University in celebration of Hyman Bass&#39;s 65th birthday. The paper details some of the history of Gorenstein rings and their uses.

Craig Huneke

We prove cancellation theorems for special ideals in Gorenstein local rings. These theorems take the form that if KI is contained in JI, then K is contained in J.

Thomas Marley, Janet C. Vassilev

Let T be a commutative Noetherian local ring of dimension at least two and R=T[x_1,...,x_n] a polynomial ring in n variables over T. Consider R as a graded ring with deg T = 0 and deg x_i = 1 for all i. Let I=R_+ and f a homogeneous polynomial whose coefficients form a system of parameters for T. We show that the socle of H^n_I(R/fR) is infinite dimensional,

Cornelius Griffin

This work examines the commutator structure of some closed subgroups of the wild group of automorphisms of a local field with perfect residue field, a group we call $\Cal J.$ In particular, we establish a new approach to evaluating commutators in $\Cal J$ and using this method investigate the normal subgroup structure of some classes of index subgroups of $\

G. K. Sankaran

The moduli space of abelian surfaces with polarisation of type (1,t) and a bilevel structure is of general type if t is odd and at least 17.

Martin R Bridson, Karen Vogtmann

The automorphism group of a finitely generated free group is the normal closure of a single element of order 2. If $m$ is less than $n$ then a homomorphism $Aut(F_n)\to Aut(F_m)$ can have cardinality at most 2. More generally, this is true of homomorphisms from $\Aut(F_n)$ to any group that does not contain an isomorphic copy of the symmetric group $S_{n+1}$

C. Series

We study limits of quasifuchsian groups for which the bending measures on the convex hull boundary tend to zero, giving necessary and sufficient conditions for the limit group to exist and be Fuchsian. As an application we complete the proof of a conjecture made in \cite{S1}, that the closure of pleating varieties for quasifuchsian groups meet Fuchsian space

L. Keen, C. Series

In this paper we give a complete description of the space $ \QF $ of quasifuchsian punctured torus groups in terms of what we call {\em pleating invariants}. These are natural invariants of the boundary $\bch$ of the convex core of the associated hyperbolic 3-manifold $M$ and give coordinates for the non-Fuchsian groups $\QF - \F$. The pleating invariants of

Bethany Marsh, Markus Reineke

In this paper we show that there is a link between the combinatorics of the canonical basis of a quantized enveloping algebra and the monomial bases of the second author arising from representations of quivers. We prove that some reparametrization functions of the canonical basis, arising from the link between Lusztig&#39;s approach to the canonical basis an

Shahn Majid

We find a unique torsion free Riemannian spin connection for the natural Killing metric on the quantum group $C_q[SL_2]$, using a recent frame bundle formulation. We find that its covariant Ricci curvature is essentially proportional to the metric (i.e. an Einstein space). We compute the Dirac operator and find for $q$ an odd $r$&#39;th root of unity that it

Andrei Frolov, Lev Kofman

We investigate the generation of primordial gravitational waves from inflation in braneworld cosmologies with extra dimensions. Advantage of using primordial gravitational waves to probe extra dimensions is that their theory depends only on the geometry, not on the microscopic models of inflation and stabilization. D(D-3)/2 degrees of freedom of the free bul

Stefano Arnone, Antonio Gatti, Tim R. Morris

A manifestly gauge invariant exact renormalization group for pure SU(N) Yang-Mills theory is proposed, along with the necessary gauge invariant regularisation which implements the effective cutoff. The latter is naturally incorporated by embedding the theory into a spontaneously broken SU(N|N) super-gauge theory, which guarantees finiteness to all orders in

Marek Rogatko

Avoiding the problem of the existence of asymptotically constant spinors satysfying certain differential equations on a non-compact hypersrface we presented the proof of positivity of the ADM and Bondi energy in Einstein-Maxwell axion-dilaton gravity. In our attitude spinor fields defining the enwergy need only be defined near infinity and there satysfying p

Ashoke Sen

Recent analysis suggests that the classical dynamics of a tachyon on an unstable D-brane is described by a scalar Born-Infeld type action with a runaway potential. The classical configurations in this theory at late time are in one to one correspondence with the configuration of a system of non-interacting (incoherent), non-rotating dust. We discuss some asp

V. A. Smirnov

Recent results on the analytical evaluation of double-box Feynman integrals and the corresponding methods of evaluation are briefly reviewed.

J. L. Goity, C. L. Schat, N. N. Scoccola

The masses of the negative parity SU(6) 70-plet baryons are analyzed in the 1/Nc expansion to order 1/Nc and to first order in SU(3) breaking. At this level of precision there are twenty predictions. Among them there are the well known Gell-Mann Okubo and equal spacing relations, and four new relations involving SU(3) breaking splittings in different SU(3) m

E. Jenkins

The masses of heavy quark baryons are studied in an expansion in 1/N_c, SU(3) flavor symmetry breaking, and heavy-quark symmetry breaking. Very accurate model-independent mass relations are obtained for charm and bottom baryons.

A. De Roeck, C. Royon

This note summarizes the discussion session on diffractive Higgs production at the DIS2002 workshop.

Jeffrey A. Bowers, Krishna Rajagopal

We describe the crystalline phase of color superconducting quark matter. This phase may occur in quark matter at densities relevant for compact star physics, with possible implications for glitch phenomena in pulsars. We use a Ginzburg-Landau approach to determine that the crystal has a face-centered-cubic (FCC) structure. Moreover, our results indicate that

L. Zhou, F. X. Lee, W. Wilcox, J. Christensen

We extract the magnetic polarizability from the quadratic response of a hadron&#39;s mass shift in progressively small static magnetic fields. The calculation is done on a 24x12x12x24 lattice at a = 0.17 fm with an improved gauge action and the clover quark action. The results are compared to those from experiments and models where available.

G. S. Guralnik, J. Doll, R. Easther, P. Emirdag

Two new approaches to numerical QFT are presented.

Ph. de Forcrand, S. Kim, T. Takaishi

Within the reweighting approach, one has the freedom to choose the Monte Carlo action so that it provides a good overlap with the finite-μmeasure but remains simple to simulate. We explore several choices of action in the regime of small μ. Simulating with a finite isospin chemical potential μ_I=μgives a better overlap than the standard choice μ=0, with no c

C. Pagliarone

Tevatron Experiments: CDF and D$\not$O collected during October 1992 and February 1996 (Run I) a data sample of roughly 120 $pb^{-1}$ $ p \bar{p}$ collisions at a center of mass energy $\sqrt{s}=$ 1.8 TeV. A large variety of physical studies have been performed using these data. Current paper reviews last results obtained searching for physics beyond the Sta

Alex Smith

New results from charm experiments have led to renewed interest in this physics. The charm sector is now seen as a powerful tool to search for new physics and to advance our understanding of the standard model. We owe much of this progress to the combination of precision vertexing and large data samples collected by recent e+e- and fixed target experiments.

P. Bernardini

MACRO experiment operated in the Gran Sasso underground laboratory. Neutrino events collected by this detector are used in order to study the atmospheric neutrino flux. Different measurements in different energy samples are in full agreement and show evidence of neutrino oscillation phenomenon. Also the search for neutrino astrophysical sources is reported.

Xiaoyan SHEN

The previous results of J/psi radiative decays from MARKIII, DM2, Crystal Ball and BESI are briefly reviewed in this talk. The main part of this talk focuses on presenting the recent results from BESII 58 million J/psi data, including the Partial Wave Analysis (PWA) results, the measurement of eta_c mass, as well as search for some interesting states.

Zhong Chao Wu

It is shown that in d=11 supergravity, under a very reasonable ansatz, the nearly flat spacetime in which we are living must be 4-dimensional without appealing to the Anthropic Principle. Can we dispel the Anthropic Principle completely from cosmology?

T. Eiter, M. Fink, G. Sabbatini, H. Tompits

Recently, several approaches to updating knowledge bases modeled as extended logic programs have been introduced, ranging from basic methods to incorporate (sequences of) sets of rules into a logic program, to more elaborate methods which use an update policy for specifying how updates must be incorporated. In this paper, we introduce a framework for reasoni

Nicola Scafetta, Sergio Picozzi, Bruce J. West

A computational model for the distribution of wealth among the members of an ideal society is presented. It is determined that a realistic distribution of wealth depends upon two mechanisms: an asymmetric flux of wealth in trading transactions that advantages the poorer of the two traders and a non-stationary creation and destruction of individual wealth. Th

T. Timusk, C. C. Homes

We discuss the peak at 400 cm-1, which is seen in c-axis conductivity spectra of underdoped high temperature superconductors. The model of van der Marel and Munzar, where the peak is the result of a transverse plasmon arising from a low frequency conductivity mode between the closely spaced planes, fits our data well. Within the model we find that the temper

F. Rivadulla, E. Winkler, J. -S. Zhou, J. B. Goodenough

Single crystals of the systems Pr0.5(Ca1-xSrx)0.5MnO3, (Pr1-yYy)0.5(Ca1-xSrx)0.5MnO3, and Sm0.5Sr0.5MnO3 were grown to provide a series of samples with fixed ratio Mn(III)/Mn(IV)=1 having geometric tolerance factors that span the transition from localized to itinerant electronic behavior of the MnO3 array. A unique ferromagnetic phase appears at the critical

Hui Zhao, Sebastian Moehl, Sven Wachter, Heinz Kalt

The in-plane transport of excitons in ZnSe quantum wells is investigated directly by microphotoluminescence in combination with a solid immersion lens. Due to the strong Froehlich coupling, the initial kinetic energy of the excitons is well controlled by choosing the excess energy of the excitation laser. When increasing the laser excess energy, we find a ge

Yin-Zhong Wu, Dong-Lai Yao, Wen Dong, Zhen-Ya Li

The polarization and the susceptibility of a ferroelectric multilayer with a non-ferroelectric slab are investigated within the framework of transverse Ising model with a four-spin interaction term. The effect of the thickness and the position of the non-ferroelectric slab are investigated in this paper. We find that the increase of the thickness of the non-

C. C. Homes, T. Vogt, S. M. Shapiro, W. Si

The cubic perovskite-related ceramic CaCu3Ti4O12 has a very high static dielectric constant ~10000 at room temperature (RT), which drops to about 100 below about 100 K. Substituting Cd for Ca reduces the RT value of the dielectric constant by over an order of magnitude. The large the dielectric constant may be due to an internal barrier layer capacitance (IB