May 2001 arXiv papers — page 11

I. Ferreras, A. Melchiorri, J. Silk

There are three independent techniques for determining the age of the universe: via cosmochronology of long-lived radioactive nuclei, via stellar modelling and population synthesis of the oldest stellar populations, and via the precision cosmology that has become feasible with the mapping of the acoustic peaks in the cosmic microwave background. We demonstra

Alberto Cappi

There is now strong evidence that the main contribution to the cosmic energy density is not due to matter, but to another component with negative pressure. Its nature is still unknown: it could be the vacuum energy, manifesting itself as a positive cosmological constant with $w \equiv P/ρc^2 = -1$ ($Λ$CDM model), a spatially inhomogeneous and dynamically evo

Monica Cerruti-Sola, Piero Cipriani, Marco Pettini

The thermodynamic behaviour of self-gravitating $N$-body systems has been worked out by borrowing a standard method from Molecular Dynamics: the time averages of suitable quantities are numerically computed along the dynamical trajectories to yield thermodynamic observables. The link between dynamics and thermodynamics is made in the microcanonical ensemble

Markus Kissler-Patig

A brief review on globular cluster sub-populations in galaxies, and their constraints on galaxy formation and evolution is given. The metal-poor and metal-rich sub-populations are put in a historical context, and their properties, as known to date, are summarized. We review why the study of these sub-populations is extremely useful for the study of galaxy fo

Hinrich Meyer

A proposal is presented to construct a very large air shower array in the densely populated central area of Nord-Rhein-Westfalen (NRW). The aim would be to reach a size of approximately 4000 km$^2$ to study the highest energy end of the all particle cosmic ray spectrum, as it is accessible in the northern hemisphere.

P. Venkatakrishnan, Brajesh Kumar, S. C. Tripathy

Motivated by the various examples of spatial variability in the power of the acoustic spectrum, we attempted to look for spatial variability in the peak frequency of the spectrum. However, the determination of this peak frequency on a spatial scale of a single pixel (8 arc seconds for the GONG data) is limited by the stochastic variations in the power spectr

D. Porquet, M. Arnaud, A. Decourchelle

We have investigated the effects of a non-thermal electron population on the ionization and recombination rates. The considered electron distribution is defined as a Maxwellian function below a break energy E_b and as a power-law function of index alpha above this energy. We have calculated the collisional (direct and excitation autoionization) ionization co

Woong-Tae Kim, Eve C. Ostriker

We investigate the susceptibility of gaseous, magnetized galactic disks to formation of self-gravitating condensations using two-dimensional, local models. We focus on two issues: (1) determining the threshold condition for gravitational runaway, taking into account nonlinear effects, and (2) distinguishing the magneto-Jeans instability (MJI) that arises und

Neil J. Cornish

The gravitational wave sky is expected to have isolated bright sources superimposed on a diffuse gravitational wave background. The background radiation has two components: a confusion limited background from unresolved astrophysical sources; and a cosmological component formed during the birth of the universe. A map of the gravitational wave background can

Richard F. Lebed

We demonstrate a concise method to enumerate the number of generalized polarizabilities---quantities characterizing the independent observables in singly-virtual Compton scattering---for a target particle of arbitrary spin s. By using crossing symmetry and J^{PC} conservation, we show that this number is (10s+1+delta_{s,0}).

Gaston Giribet, Carmen Nunez

The computation of two and three point functions in the Coulomb gas free field approach to string theory in the SL(2,R)/U(1) black hole background is reviewed. An interesting relation arises when comparing the results obtained using two different screening operators. The formalism is then modified to study string theory propagating in AdS$_3$ which is consid

J. M. Miller, R. Wijnands, J. Homan, T. Belloni

We present an analysis of the high frequency timing properties of the April-May 2000 outburst of the black hole candidate and Galactic microquasar XTE J1550-564, measured with the Rossi X-ray Timing Explorer. The rapid X-ray variability we measure is consistent with the source being in either the ``very high'' or ``intermediate'' black hole s

Gabor Zala, B. N. Narozhny, I. L. Aleiner

It is well known that electron-electron interaction in disordered systems leads to logarithmically divergent Altshuler-Aronov corrections to conductivity at low temperatures ($Tτ\ll 1$; $τ$ is the elastic mean-free time). This paper is devoted to the fate of such corrections at intermediate temperatures $Tτ\ge 1$. We show that in this (ballistic) regime the

Jens. O Andersen, Michael Strickland

The thermodynamics of massless phi^4-theory is studied within screened perturbation theory (SPT). In this method the perturbative expansion is reorganized by adding and subtracting a mass term in the Lagrangian. We analytically calculate the pressure and entropy to three-loop order and the screening mass to two-loop order, expanding in powers of m/T. The tru

P. A. Movilla Fernandez, S. Bethke, O. Biebel, S. Kluth

A study of perturbative QCD calculations combined with power corrections to model hadronisation effects is presented. The QCD predictions are fitted to differential distributions and mean values of event shape observables measured in e+e- annihilation at centre-of-mass energies from 14 to 189 GeV. We investigate the event shape observables thrust, heavy jet

K. R. Brown, D. A. Lidar, K. B. Whaley

Motivated by the recently demonstrated ability to attach quantum dots to polymers at well defined locations, we propose a condensed phase analog of the ion trap quantum computer: a scheme for quantum computation using chemically assembled semiconductor nanocrystals attached to a linear support. The linear support is either a molecular string (e.g., DNA) or a

Yakir Aharonov, Lev Vaidman

In this paper we present the two-state vector formalism of quantum mechanics. It is a time-symmetrized approach to standard quantum theory particularly helpful for the analysis of experiments performed on pre- and post-selected ensembles. Several peculiar effects which naturally arise in this approach are considered. In particular, the concept of ``weak meas

Edi Halyo

We describe a model of hybrid quintessence in which in addition to the tracker field there is a trigger field which is responsible for ending quintessence. As a result, hybrid quintessence does not suffer from the problems associated with the eternal acceleration of the universe. We derive the hybrid quintessence potential on branes from the interbrane inter

A. Z. Gazizov, S. I. Yanush

An unknown small-x behavior of nucleon structure functions gives appreciable uncertainties to high-energy neutrino-nucleon cross-sections. We construct structure functions using at small x Regge inspired description by A. Donnachie and P. V. Landshoff with soft and hard pomerons, and employing at larger x the perturbative QCD expressions. The smooth interpol

Stefan Forste, Gabriele Honecker, Ralph Schreyer

We present supersymmetry breaking four dimensional orientifolds of type IIA strings. The compact space is a torus times a four dimensional orbifold. The orientifold group reflects one direction in each torus. RR tadpoles are cancelled by D6-branes intersecting at angles in the torus and in the orbifold. The angles are chosen such that supersymmetry is broken

M. Diehl, G. Hiller

We show that the CKM phase $2 β+γ$ can be extracted from measurement of the time dependent rates in the decays $\bar{B}^0 \to D^{(*)\pm} M^\mp$ and $B^0 \to D^{(*)\pm} M^\mp$, where $M=a_0$, $π(1300)$, $b_1$, $a_2$, $π_2$, $ρ_3$. These channels have a large asymmetry between decays of $\bar{B}^0$ and $B^0$ into the same final state. Even though the branching

J. H. Miller,, G. Cardenas, A. Garcia, W. More

We report on a macroscopic version of the single-electron transistor (SET), which we call the soliton tunneling transistor (STT). The STT, consists of a gate capacitor coupled to a NbSe$_{3}$ crystal with a charge density wave (CDW). The current-voltage characteristic of an STT is periodically modulated by the gate voltage, as in the SET,except that the peri

C. P. Burgess, M. Majumdar, D. Nolte, F. Quevedo

We show how the motion through the extra dimensions of a gas of branes and antibranes can, under certain circumstances, produce an era of inflation as seen by observers trapped on a 3-brane, with the inflaton being the inter-brane separation. Although most of our discussion refers to arbitrary p-branes, when we need to be specific we assume that they are D-b

A. H. Chamseddine, W. A. Sabra

We study curved domain wall solutions for gauged supergravity theories obtained by gauging some of the isometries of the manifold spanned by the scalars of vector and hypermultiplets. We first consider the case obtained by compactifying M-theory on a Calabi-Yau threefold in the presence of G-fluxes. It is found that supersymmetry allows for the construction

Gian Luigi Alberghi, Elena Caceres, Kevin Goldstein, David A. Lowe

We present a candidate supergravity solution for a stacked configuration of stable non-BPS D-branes in Type II string theory compactified on T^4/Z_2. This gives a supergravity description of nonabelian tachyon condensation on the brane worldvolume.

M. M. Sargsian, S. Simula, M. I. Strikman

A detailed study of inclusive deep inelastic scattering (DIS) from mirror A = 3 nuclei at large values of the Bjorken variable x is presented. The main purpose is to estimate the theoretical uncertainties on the extraction of the neutron DIS structure function from such nuclear measurements. On one hand, within models in which no modification of the bound nu

W. Grimus, L. Lavoura

We consider lepton mixing in an extension of the Standard Model with three right-handed neutrino singlets. We require that the three lepton numbers L_e, L_\mu, and L_\tau be separately conserved in the Yukawa couplings, and we assume that they are softly broken only by the Majorana mass matrix M_R of the neutrino singlets. In this framework, where lepton-num

S. Oberholzer, E. V. Sukhorukov, C. Strunk, C. Schoenenberger

Shot noise of series quantum point contacts forming a sequence of cavities in a two dimensional electron gas are studied theoretically and experimentally. Noise in such a structure originates from local scattering at the point contacts as well as from chaotic motion of the electrons in the cavities. We found that the measured shot noise is in reasonable agre

Chong-Sun Chu, Valentin V. Khoze, Gabriele Travaglini

We propose a new mechanism of spontaneous supersymmetry breaking in noncommutative gauge theories. We find that in N=1 noncommutative gauge theories both supersymmetry and gauge invariance are dynamically broken. Supersymmetry is broken spontaneously by a Fayet-Iliopoulos D-term which naturally arises in a noncommutative U(n) theory. For a non-chiral matter

T. Duguet, P. Bonche, P. -H. Heenen, J. Meyer

In order to extract informations on pairing correlations in nuclei from experimental mass differences, the different contributions to odd-even mass differences are investigated within the Skyrme HFB method. In this first paper, the description of odd nuclei within HFB is discussed since it is the key point for the understanding of the above mentioned contrib

Hongchen Fu, Xiaoguang Wang, Allan I Solomon

A necessary and sufficient condition for the maximal entanglement of bipartite nonorthogonal pure states is found. The condition is applied to the maximal entanglement of coherent states. Some new classes of maximally entangled coherent states are explicited constructed; their limits give rise to maximally entangled Bell-like states.

D. Brace, B. L. Cerchiai, A. F. Pasqua, U. Varadarajan

We present a cohomological method for obtaining the non-Abelian Seiberg-Witten map for any gauge group and to any order in theta. By introducing a ghost field, we are able to express the equations defining the Seiberg-Witten map through a coboundary operator, so that they can be solved by constructing a corresponding homotopy operator.

Vicente Garzó, J. W. Dufty

Hydrodynamic equations for a binary mixture of inelastic hard spheres are derived from the Boltzmann kinetic theory. A normal solution is obtained via the Chapman-Enskog method for states near the local homogeneous cooling state. The mass, heat, and momentum fluxes are determined to first order in the spatial gradients of the hydrodynamic fields, and the ass

Igor Batalin, Robert Marnelius

A general master action in terms of superfields is given which generates generalized Poisson sigma models by means of a natural ghost number prescription. The simplest representation is the sigma model considered by Cattaneo and Felder. For Dirac brackets considerably more general models are generated.

E. Müller-Hartmann, A. Reischl

The derivation of effective spin models describing the low energy magnetic properties of undoped CuO_2-planes is reinvestigated. Our study aims at a quantitative determination of the parameters of effective spin models from those of a multi-band model and is supposed to be relevant to the analysis of recent improved experimental data on the spin wave spectru

Edvard Moertsell, Christofer Gunnarsson, Ariel Goobar

We investigate the effects of gravitational lensing due to intervening galaxies on the recently discovered Type Ia supernova at z=1.7, SN1997ff, in the Hubble Deep Field North. We find that it is possible to obtain a wide range of magnifications by varying the mass and/or the velocity dispersion normalization of the lensing galaxies. In order to be able to u

Ion I. Cotăescu, Mihai Visinescu

In a previous article it was proved that the extensions of the Taub-NUT geometry do not admit Killing-Yano tensors, even if they possess St\" {a}ckel-Killing tensors. Here the analysis is taken further, and it is shown that, in general, this class of metrics does not even admit f-symbols. The only exception is the original Taub-NUT metric which possesses

Seiho Matsumoto, Makoto Sakamoto, Shogo Tanimura

We propose a field theoretical model that exhibits spontaneous breaking of the rotational symmetry. The model has a two-dimensional sphere as extra dimensions of the space-time and consists of a complex scalar field and a background gauge field. The Dirac monopole, which is invariant under the rotations of the sphere, is taken as the background field. We sho

Gianluca Occhetta, Jaroslaw A. Wisniewski

Let X be a complete toric variety and let Y be a smooth projective variety with Picard number one. We prove that, if there exists a surjective morphism from X to Y, then Y is a projective space.

K. Takahashi, M. Watanabe, K. Sato, T. Totani

The effects of three-flavor neutrino oscillation on the supernova neutrino spectrum are studied. We calculate the expected event rate and energy spectra, and their time evolution at the Superkamiokande (SK) and the Sudbury Neutrino Observatory (SNO), by using a realistic neutrino burst model based on numerical simulations of supernova explosions. We also emp

Luca Peliti

I consider a class of fitness landscapes, in which the fitness is a function of a finite number of phenotypic "traits", which are themselves linear functions of the genotype. I show that the stationary trait distribution in such a landscape can be explicitly evaluated in a suitably defined "thermodynamic limit", which is a combination of infi

Yang Sun, Javid A. Sheikh

Recent experiments have demonstrated that the rotational-alignment for the $N=Z$ nuclei in the mass-80 region is considerably delayed as compared to the neighboring $N \ne Z$ nuclei. We investigate whether this observation can be understood by a known component of nuclear residual interactions. It is shown that the quadrupole-pairing interaction, which expla

Zeng-Bing Chen, Jian-Wei Pan, Yong-De Zhang

We propose a feasible scheme to create $n$-party ($n\geq 2$) polarization-entangled photon states in a controllable way. The scheme requires only single-photon sources, single-photon quantum non-demolition measurement (SP-QNDM) and simple linear optical elements, usually with high perfections. The SP-QNDM acts as a non-destructive projection measurement onto

Graeme Mitchison, Serge Massar, Stefano Pironio

We give a bound on the minimum number of photons that must be absorbed by any quantum protocol to distinguish between two transparencies. We show how a quantum Zeno method in which the angle of rotation is varied at each iteration can attain this bound in certain situations.

Ulrich Mohrhoff

Several errors in Stapp's interpretation of quantum mechanics and its application to mental causation (Henry P. Stapp, "Quantum theory and the role of mind in nature," e-Print quant-ph/0103043) are pointed out. An interpretation of (standard) QM that avoids these errors is presented.

Jose L. Cereceda

We consider a situation in which two parties, Alice and Bob, share a 3-qubit system coupled in an initial maximally entangled, GHZ state. By manipulating locally two of the qubits, Alice can prepare any one of the eight 3-qubit GHZ states. Thus the sending of Alice's two qubits to Bob, entails 3 bits of classical information which can be recovered by Bob

Malik Rakhmanov

The Doppler effect in Fabry-Perot cavities with suspended mirrors is analyzed. Intrinsically small, the Doppler shift accumulates in the cavity and becomes comparable to or greater than the line-width of the cavity if its finesse is high or its length is large. As a result, damped oscillations of the cavity field occur when one of the mirrors passes a resona

T. Binnewies, G. Wilpers, U. Sterr, F. Riehle

Ultracold atoms at temperatures close to the recoil limit have been achieved by extending Doppler cooling to forbidden transitions. A cloud of ^40Ca atoms has been cooled and trapped to a temperature as low as 6 μK by operating a magneto-optical trap on the spin-forbidden intercombination transition. Quenching the long-lived excited state with an additional

Min Yan, Edward G. Rickey, Yifu Zhu

We report an experimental demonstration of photon switching by quantum interference in a four-level atomic system proposed by Harris and Yamamoto (Phys. Rev. Lett. 81, 3611 (1998)). Quantum interference inhibits single-photon absorption but enhances third-order, two-photon type absorption in the four-level system. We have observed greatly enhanced nonlinear

Ding-Yu Chung

The cyclic universe model is a modification of the ekpyrotic universe and the pyrotechnic universe models. The cyclic universe goes through the six transitions: the triplet universe, the inflation, the big bang, the quintessence, the big crush, and the deflation transitions. The universe starts with eleven dimensional space-time with two boundary 9-branes se

Xin-Nian Wang

Coherence, multiple scattering and the interplay between soft and hard processes are discussed. These physics phenomena are essential for understanding the nuclear dependences of rapidity density and $p_T$ spectra in high-energy heavy-ion collisions. The RHIC data have shown the onset of hard processes and indications of high $p_T$ spectra suppression due to

Thomas R. Hemmert

Recent developments in calculations of low energy nucleon properties utilizing effective chiral field theories with explicit spin 3/2 matter fields are presented. In particular, the role of Delta resonances in microscopic calculations of the anomalous magnetic moments of the Nucleon is discussed and a comparison to lattice data is performed. Furthermore, the

T. Duguet, P. Bonche, P. -H. Heenen, J. Meyer

The odd-even mass staggering in nuclei is analyzed in the context of self-consistent mean-field calculations, for spherical as well as for deformed nuclei. For these nuclei, the respective merits of the energy differences $Δ^{(3)}$ and $Δ^{(5)}$ to extract both the pairing gap and the time-reversal symmetry breaking effect at the same time are extensively di

Inkyu Park, The PHOBOS Collaboration

The measurement of elliptic flow for charged particles in Au-Au collisions at $\sqrt{s_{_{NN}}} = 130$ GeV using the PHOBOS detector at the Relativistic Heavy Ion Collider (RHIC) is presented. Charge particle distributions over a wide pseudo-rapidity region ($|η|<5.3$) are measured by the PHOBOS silicon multiplicity detectors. These distributions are used to

G. David, PHENIX Collaboration

Transverse momentum spectra for identified $π^0$&#39;s in the range 1 GeV/c $< p_T <$ 4 GeV/c have been measured by the PHENIX experiment in Au-Au collisions at $\sqrt{s}=130$ GeV. The spectra from peripheral nuclear collisions are consistent with the simple expectation of scaling the spectra from p+p collisions by the average number of nucleon-nucleon binar

Joachim Weber, Fritz Haake, Petr A. Braun, Christopher Manderfeld

Resonances of the (Frobenius-Perron) evolution operator P for phase-space densities have recently attracted considerable attention, in the context of interrelations between classical and quantum dynamics. We determine these resonances as well as eigenvalues of P for Hamiltonian systems with a mixed phase space, by truncating P to finite size in a Hilbert spa

Janne V. Kujala, Tuomas J. Lukka

We analyze the steady-state flow as a function of the initial density for a class of deterministic cellular automata rules (``traffic rules&#39;&#39;) with periodic boundary conditions [H. Fuks and N. Boccara, Int. J. Mod. Phys. C 9, 1 (1998)]. We are able to predict from simple considerations the observed, unexpected cutoff of the average flow at unity. We

Mark D. Gould, Wen-Li Yang, Yao-Zhong Zhang, Shao-You Zhao

We propose a general method for constructing boundary integrable Gaudin models associated with (twisted) affine algebras ${\cal G}^{(k)} (k=1, 2)$, where ${\cal G}$ is a simple Lie algebra or superalgebra. Many new integrable Gaudin models with boundaries are constructed using this approach.

Fritz Gesztesy, Helge Holden

We provide a detailed treatment of the Camassa--Holm (CH) hierarchy with special emphasis on its algebro-geometric solutions. In analogy to other completely integrable hierarchies of soliton equations such as the KdV or AKNS hierarchies, the CH hierarchy is recursively constructed by means of basic polynomial formalism invoking a spectral parameter. Moreover

Jamal Berakdar

This work reviews recent advances in the analytical treatment of the continuum spectrum of correlated few-body non-relativistic Coulomb systems. The exactly solvable two-body problem serves as an introduction to the non-separable three-particle system. For the latter case we discuss the existence of an approximate separability of the long and the short-range

Christopher J Fewster, Rainer Verch

Quantum fields are well known to violate the weak energy condition of general relativity: the renormalised energy density at any given point is unbounded from below as a function of the quantum state. By contrast, for the scalar and electromagnetic fields it has been shown that weighted averages of the energy density along timelike curves satisfy `quantum we

Rafe Mazzeo, Frank Pacard

We examine here the space of conformally compact metrics $g$ on the interior of a compact manifold with boundary which have the property that the $k^{th}$ elementary symmetric function of the Schouten tensor $A_g$ is constant. When $k=1$ this is equivalent to the familiar Yamabe problem, and the corresponding metrics are complete with constant negative scala

Tatsuya Akasaka

We construct an integral PBW basis and an integral crystal basis of the quantum affine algebra of type A$_{2}^{(2)}$.

Mina Teicher

In this paper we present the Braid Monodromy Type (BMT) of curves and surfaces; past, present and future. The BMT is an invariant that can distinguish between non-isotopic curves; between different families of surfaces of general type; between connected components of moduli space of surfaces and between non symplectmorphic 4-manifolds. BMT is a finer invaria

Hai-Shan Han, Zun-Quan Xia, Antonino Del Popolo

This paper is to explore a model of the ABS Algorithms for dealing with a class of systems of linear stochastic equations A xi=eta satisfying eta sim N_m(v, I_{m}). It is shown that the iteration step alpha_{i} is N(V,π) and approximation solutions is xi_{i} \sim N_n(U,Σ) for this algorithm model. And some properties of (V,π)$ and $(U,Σ) are given.

Xing Li, Ying Liu, Antonino Del Popolo

This report is devoted to some C++ codes implementing the implicit LU class algorithms for solving linear determined, and undetermined systems with $n$ variables and $m$ equations. A main program used in part of the numerical test is given in the last section.

Rita Ferraro

Let C be a reduced, irreducible, not degenerate curve, not contained on surfaces of degree <s; when d=deg(C) is large with respect to s, the arithmetic genus p_a(c) is bounded by a function G(d, r, s) which is of type d^2/2s+O(d). The existence of such a bound for curves in P^3 was announced by Halphen in 1870 and proved by Gruson and Peskine in 1978; for cu

Alexander Soshnikov

We prove that under fairly general conditions properly rescaled determinantal random point field converges to a generalized Gaussian random process.

Xingang Chen, Erick J. Weinberg

We use the moduli space approximation to study the time evolution of magnetically charged configurations in a theory with an SU(N+2) gauge symmetry spontaneously broken to U(1) x SU(N) x U(1). We focus on configurations containing two massive and N-1 massless monopoles. The latter do not appear as distinct objects, but instead coalesce into a cloud of non-Ab

E. Ivanov

We outline, on a few instructive examples, the characteristic features of the approach to superbranes and super Born-Infeld theories based on the concept of partial spontaneous breaking of global supersymmetry (PBGS). The examples include the N=1, D=4 supermembrane and the ``space-filling&#39;&#39; D2- and D3-branes. Besides giving a short account of the ava

J. F. Sparks

We examine Kaluza-Klein branes in detail. Specifically, we show that codimension four submanifolds that are stationary under a semi-free circle action may be interpreted as branes or antibranes in the Kaluza-Klein reduced space that are magnetically charged under the Kaluza-Klein field strength. We derive the equation in cohomology that is satisfied by such

John Ellis, N. E. Mavromatos, D. V. Nanopoulos

An accelerating Universe can be accommodated naturally within non-critical string theory, in which scattering is described by a superscattering matrix \$ that does not factorize as a product of $S$- and $S^\dagger$-matrix elements and time evolution is described by a modified Liouville equation characteristic of open quantum-mechanical systems. We describe b

G. Dvali, Q. Shafi, S. Solganik

We discuss a calculable version of brane inflation, in which a set of parallel D-brane and anti-D-brane worlds, initially displaced in extra dimension, slowly attract each other. In the effective four-dimensional theory this slow motion of branes translates into a slow-roll of a scalar field (proportional to their separation) with a flat potential that drive

Ron Y. Donagi, Justin Khoury, Burt A. Ovrut, Paul J. Steinhardt

It is shown that there exist large classes of BPS vacua in heterotic M-theory which have negative tension on the visible orbifold plane, positive tension on the hidden plane and positive tension, physical five-branes in the bulk space. Explicit examples of such vacua are presented. Furthermore, it is demonstrated that the ratio, beta/|alpha|, of the bulk fiv

Y. M. Cho, H. W. Lee, D. G. Pak

We calculate a one loop effective action of SU(2) QCD in the presence of the monopole background, and find a possible connection between the resulting QCD effective action and a generalized Skyrme-Faddeev action of the non-linear sigma model. The result is obtained using the gauge-independent decomposotion of the gauge potential into the topological degrees

V. I. Inozemtsev, R. Sasaki

The universal formulation of spin exchange models related to Calogero-Moser models implies the existence of integrable hierarchies, which have not been explored. We show the general structures and features of the spin exchange model hierarchies by taking as examples the well-known Heisenberg spin chain with the nearest neighbour interactions. The energy spec

Subir Ghosh

The Hamiltonian dynamics of a compressible inviscid fluid is formulated as a gauge theory. The idea of gauge equivalence is exploited to unify the study of apparantly distinct physical problems and solutions of new models can be generated from known fluid velocity profiles.

Ralf Schützhold, Ralf Kuhn, Michael Meyer-Hermann, Günter Plunien

We prove that the massless neutral $λΦ^4$-theory does not possess a unique vacuum. Based on the Wightman axioms the non-existence of a state which preserves Poincar{é} and scale invariance is demonstrated non-perturbatively for a non-vanishing self-interaction. We conclude that it is necessary to break the scale invariance in order to define a vacuum state.

Ulrich Nierste

Next-to-leading order QCD corrections to the width difference Delta Gamma in the B_s-meson system are presented. I further discuss how Delta Gamma can be used to detect new physics.

R. Escribano, J. -M. Frere, D. Monderen, V. Van Elewyck

We discuss the gravitational lensing of neutrinos by astrophysical objects. Unlike photons, neutrinos can cross a stellar core; as a result, the lens quality improves. We also estimate the depletion of the neutrino flux after crossing a massive object and the signal amplification expected. While Uranians alone would benefit from this effect in the Sun, simil

Kazutaka Sudoh, Han-Wen Huang, Toshiyuki Morii

In order to get information about the polarized gluon distribution in a proton, we studied the electroproduction of ψ&#39; in polarized electron and polarized proton collisions in the framework of the NRQCD factorization approach. The value of the cross section dΔσ/ dp_T^2 for color-octet mechanism is about 5 times larger than that for color-singlet one, and

V. A. Petrov, A. V. Prokudin

A model of a three Pomeron contribution to high energy elastic $pp$ and $\bar p p$ scattering is proposed. The data are well described for all momenta ($0.01\le |t|\le 14. GeV^2$) and energies ($8.\le\sqrt{s}\le 1800. GeV$) ($χ^2/{\rm d.o.f.}=2.74$). The model predicts the appearance of two dips in the differential cross-section which will be measured at LHC

I. V. Andreev

The photon production arising due to time variation of the medium has been considered. The Hamilton formalism for photons in time-variable medium (plasma) has been developed with application to inclusive photon production. The results have been used for calculation of the photon production in the course of transition from quark-gluon phase to hadronic phase

J. C. Collins, J. Pumplin

We propose a new and rather stringent criterion for testing the goodness of fit between a theory and experiment. It is motivated by the paradox that the criterion on χ^2 for testing a theory is much weaker than the criterion for finding the best fit value of a parameter in the theory. We present a method by which the stronger parameter-fitting criterion can

E. Levin

This talk is an attempt to review all our knowledge on saturation at low $x$ both theoretical and experimental, to stimulate a search for saturation effects at THERA. The main goals of this presentation are 1. To discuss an intuitive picture of the deep inelastic scattering that leads to the saturation of the parton densities; 2. To show that the saturation

Tsung-Wen Yeh

We proposed a new formulation for heavy quark effective theory (HQET), whose Lagrangian is hermitian and has a manifest reparameterization invariance. As an application, we calculated the semileptonic and nonleptonic inclusive heavy hadron decay rates up to second order mass corrections and found that there are no kinetic energy correction terms.

B. Aubert, BABAR Collaboration

We present measurements of the branching fractions and a search for CP-violating charge asymmetries in charmless hadronic decays of B mesons into two-body final states of kaons and pions. The results are based on a data sample of approximately 23 million BB(bar) pairs collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. We find the fol

Mark Mandelkern

The PEP-N experiment requires a fast on-line luminosity monitor of modest accuracy plus an off-line method of determining integrated luminosity with accuracy of 0.01 for each pb$^{-1}$. We propose the PEP-2 monitor, based on observing single bremsstrahlung at zero degrees to the positron direction at collision for the former and the use of Bhabha scatters at

Pablo Garcia-Abia

A search for pair-produced charged Higgs bosons is performed with the L3 detector at LEP using data collected at centre-of-mass energies between 200 and 209 GeV, corresponding to an integrated luminosity of 217.8 pb^-1. We observe an excess of events in the H+-H -> cscs and csτνchannels in the mass region around 68 GeV, which is most significant at low value

G. Oliveira-Neto

We study an analytical solution to the Einstein&#39;s equations in 2+1-dimensions, representing the self-similar collapse of a circularly symmetric, minimally coupled, massless, scalar field. Depending on the value of certain parameters, this solution represents the formation of black holes. Since our solution is asymptotically flat, our black holes do not h

Gerald Vones

It is postulated that the action of the FRW-universe is the cosmological term of Einsteins theory (no curvature term - R0 Cosmology). The expansion equation emerging from the embedding of this most simple brane world with variable speed of light is deduced. The universal dimensionless coupling constant of gravity is addressed. Some implications on the deep p

Maximiliano Ujevic, Patricio S. Letelier

Analytical and numerical solutions for the integral curves of the velocity field (streamlines) of a steady-state flow of an ideal fluid with $p = ρ$ equation of state are presented. The streamlines associated with an accelerate black hole and a rigid sphere are studied in some detail, as well as, the velocity fields of a black hole and a rigid sphere in an e

Steven Bird, Gary Simons

As language data and associated technologies proliferate and as the language resources community rapidly expands, it has become difficult to locate and reuse existing resources. Are there any lexical resources for such-and-such a language? What tool can work with transcripts in this particular format? What is a good format to use for linguistic data of this

Eran Halperin, Ram Nathaniel, Uri Zwick

We obtain the following new coloring results: * A 3-colorable graph on $n$ vertices with maximum degree~$Δ$ can be colored, in polynomial time, using $O((Δ\logΔ)^{1/3} \cdot\log{n})$ colors. This slightly improves an $O((Δ^{{1}/{3}} \log^{1/2}Δ)\cdot\log{n})$ bound given by Karger, Motwani and Sudan. More generally, $k$-colorable graphs with maximum degree $

Jian-Xin Zhu, C. S. Ting

The local density of states (LDOS) at one of the vortex lattice cores in a high Tc superconductor is studied by using a self-consistent mean field theory including interactions for both antiferromagnetism (AF) and d-wave superconductivity (DSC). The parameters are chosen in such a way that in an optimally doped sample the AF order is completely suppressed wh

Andreas Kluemper, Kazumitsu Sakai

We study an integrable model of one-dimensional strongly correlated electrons at finite temperature by explicit calculation of the correlation lengths of various correlation functions. The model is invariant with respect to the quantum superalgebra U_q(sl(2|1)) and characterized by the Hubbard interaction, correlated hopping and pair-hopping terms. Using the

G. Drazer, J. Koplik, B. Khusid, A. Acrivos

The dynamics of macroscopically homogeneous sheared suspensions of neutrally buoyant, non-Brownian spheres is investigated in the limit of vanishingly small Reynolds numbers using Stokesian dynamics. We show that the complex dynamics of sheared suspensions can be characterized as a chaotic motion in phase space and determine the dependence of the largest Lya

Yuriy Makhlin, Alexander Mirlin

Statistics of charge transport in an adiabatic pump are determined by the dynamics of the scattering matrix S(t). We show that, up to an integer offset, the statistics depend only on the corresponding path N(t)=S^\daggerσ_3 S in the coset space (the sphere for a single channel). For a general loop S(t) we solve for the noise-minimizing pumping strategy. The

V. K. Thorsmølle, R. D. Averitt, M. P. Maley, L. N. Bulaevskii

We have unambiguously observed the c-axis Josephson Plasma Resonance (JPR) in high-T$_{c}$ cuprate Tl$_{2}$Ba$_{2}$CaCu$_{2}$O$_{8}$ superconducting thin films employing terahertz time-domain spectroscopy in transmission as a function of temperature in zero magnetic field. These are the first measurements of the JPR temperature dependence of a high-$T_{c}$ m

Qing-feng Sun, Hong Guo

We present a theoretical analysis of a possible route for directly detecting Kondo resonances in local density of states (LDOS) of an interacting quantum dot. By very weakly couple a third and/or a fourth lead to a two-probe quantum dot and measuring differential conductance through these extra links, we show that Kondo peaks directly map onto the differenti