August 2000 arXiv papers — page 21

A. van Hameren, R. Kleiss

An extension of the SARGE-algorithm of \cite{HKD} is introduced, which includes the incoming momenta in the kinematical pole structure of the density with which the momenta are generated. The algorithm is compared with RAMBO in the integration of QCD-amplitudes in the SPHEL-approximation, and the computing times are extrapolated to those for the calculation

J. F. Bennett, J. A. Gracey

We consider the n -> 0 limit of the DGLAP splitting function gamma_gg(a) at all orders in the strong coupling constant, a, by analysing the leading order large N_f form of the associated d-dimensional critical exponent. We show that for unpolarized scattering the pole at n = 0 which appears in successive orders in perturbation theory is absent in the resumme

F. E. Close, A. Kirk

We suggest that mixing between the f0(980) and a0(980), due to their dynamical interaction with the nearby KKbar thresholds, can give rise to a significantly enhanced production rate of a0(980) relative to a2(1320) in pp -> ps (eta pi0) pf as xF -> 0. The peaking of the cross section as phi -> 0 should also occur. We show that such effects are seen in data a

Yuichiro Kiyo, Jiro Kodaira, Kazushige Morii

We discuss top quark production and its subsequent decay for searching new physics at lepton colliders. The angular dependence of the decay leptons is calculated including both QCD corrections and anomalous gamma Z - t tbar couplings. The off-diagonal spin basis for the top and anti-top quarks is shown to be useful to probe the anomalous couplings.

C. Boros, V. Guzey, M. Strikman, A. W. Thomas

We consider the effect of the transitions $n \to \Delta^{0}$ and $p \to \Delta^{+}$ in deep inelastic scattering on polarized $^3$He on the extraction of the neutron spin structure function $g_{1}^{n}(x,Q^2)$. Making the natural assumption that these transitions are the dominant non-nucleonic contributions to the renormalization of the axial vector coupling

Biswajoy Brahmachari

We discuss how predictions of Fritzsch textures can be consistent with values of fermion masses and mixing angles if we embed them in a supersymmetric grand unified theory.

M. Daum, M. Janousch, P-R. Kettle, J. Koglin

We have searched for the pion decay pi^+ --> mu^+ X, where X is a neutral particle of mass 33.905 MeV. This process was suggested by the KARMEN Collaboration to explain an anomaly in their observed time distribution of neutrino induced reactions. Having measured the muon momentum spectrum of charged pions decaying in flight, we find no evidence for this proc

ALEPH Collaboration

Hadronic Z decay data taken with the ALEPH detector at LEP1 are used to measure the three-jet rate as well as moments of various event-shape variables. The ratios of the observables obtained from b-tagged events and from an inclusive sample are determined. The mass of the b quark is extracted from a fit to the measured ratios using a next-to-leading order pr

S. Kettell

The status of rare kaon decay experiments is reviewed. With the current generation of experiments now finishing, several exciting new results are available. New limits in the search for Lepton Flavor Violation (LFV) will be discussed, as will new limits and measurements of the CKM matrix parameters. The next generation of rare kaon decay experiments and thei

Keith H. Lockitch, Nils Andersson, John L. Friedman

We study the r-modes and rotational ``hybrid'' modes of relativistic stars. As in Newtonian gravity, the spectrum of low-frequency rotational modes is highly sensitive to the stellar equation of state. If the star and its perturbations obey the same one-parameter equation of state (as with isentropic stars), there exist {\it no pure r-modes at all} -

Stefano Liberati, Tony Rothman, Sebastiano Sonego

Recent results of quantum field theory on a curved spacetime suggest that extremal black holes are not thermal objects and that the notion of zero temperature is ill-defined for them. If this is correct, one may have to go to a full semiclassical theory of gravity, including backreaction, in order to make sense of the third law of black hole thermodynamics.

Mark Miller

We perform a von Neumann stability analysis on a common discretization of the Einstein equations. The analysis is performed on two formulations of the Einstein equations, namely, the standard ADM formulation and the conformal-traceless (CT) formulation. The eigenvalues of the amplification matrix are computed for flat space as well as for a highly nonlinear

Alexander Yeh

Statistical significance testing of differences in values of metrics like recall, precision and balanced F-score is a necessary part of empirical natural language processing. Unfortunately, we find in a set of experiments that many commonly used tests often underestimate the significance and so are less likely to detect differences that exist between differe

Alexander Yeh

Grammatical relationships (GRs) form an important level of natural language processing, but different sets of GRs are useful for different purposes. Therefore, one may often only have time to obtain a small training corpus with the desired GR annotations. On such a small training corpus, we compare two systems. They use different learning techniques, but we

R. Mulet, R. Cruz, E. Altshuler

Using a simple cellular automaton with stochastic rules we show the possible emergence of thermally activated avalanches (power law distributed) in type-II superconductors. Scaling relations between the exponents characterizing these distributions and those obtained from field driven experiments are derived and proved through simulations. It is also shown th

Michio Watanabe

We have measured the electrical conductivity of Ge:Ga samples prepared by neutron-transmutation doping of isotopically enriched 70Ge single crystals in order to study the metal-insulator transition (MIT) ruling out an ambiguity due to inhomogeneous distribution of impurities. The critical exponent for the zero-temperature conductivity is 0.5 in zero magnetic

Eugene Demler, Chetan Nayak, Sankar Das Sarma

We consider a fully spin-polarized quantum Hall system with no interlayer tunneling at total filling factor $ν=1/k$ (where $k$ is an odd integer) using the Chern-Simons-Ginzburg-Landau theory. Exploiting particle-vortex duality and the concept of quantum disordering, we find a large number of possible compressible and incompressible ground states, some of wh

R. W. Nunes, David Vanderbilt

In a recent Letter [N. Lehto and S. Oberg, Phys. Rev. Lett. 80, 5568 (1998)], Lehto and Oberg investigated the effects of strain fields on the core structure of the 90-degree partial dislocation in silicon, especially the influence of the choice of supercell periodic boundary conditions in theoretical simulations. We show that their results for the relative

R. W. Nunes, David Vanderbilt

We compare the models that have been proposed in the literature for the atomic structure of the 90-degree partial dislocation in the homopolar semiconductors, silicon, diamond, and germanium. In particular, we examine the traditional single-period and our recently proposed double-period core structures. Ab-initio and tight-binding results on the core energie

Yoram Louzoun, Sorin Solomon, Henri Atlan, Irun R. Cohen

Biological systems, unlike physical or chemical systems, are characterized by the very inhomogeneous distribution of their components. The immune system, in particular, is notable for self-organizing its structure. Classically, the dynamics of natural systems have been described using differential equations. But, differential equation models fail to account

M. Weissmann, A. M. Llois

The spectroscopic characteristics of systems with adsorbed d impurities on noble metal surfaces should depend on the number and geometric arrangement of the adsorbed atoms and also on their d band filling. Recent experiments using scanning tunneling microscopy have probed the electronic structure of all 3d transition metal impurities and also of Co dimers ad

C. Simserides

We calculate the electronic states of Al$_x$Ga$_{1-x}$As/GaAs/Al$_x$Ga$_{1-x}$As double heterojunctions subjected to a magnetic field parallel to the quasi two-dimensional electron gas. We study the energy dispersion curves, the density of states, the electron concentration and the distribution of the electrons in the subbands. The parallel magnetic field in

F. A. B. F. de Moura, U. Tirnakli, M. L. Lyra

For a family of logistic-like maps, we investigate the rate of convergence to the critical attractor when an ensemble of initial conditions is uniformly spread over the entire phase space. We found that the phase space volume occupied by the ensemble $W(t)$ depicts a power-law decay with log-periodic oscillations reflecting the multifractal character of the

A. N. Timoshevskii, V. A. Timoshevskii, B. Z. Yanchitsky

Carbon and nitrogen austenites, modeled by Fe8N and Fe8C superstructures are studied by full-potential LAPW method. Structure parameters, electronic and magnetic properties as well as hyperfine interaction parameters are obtained. Calculations prove that Fe-C austenite can be successfully modeled by ordered Fe8C superstructure. The results show that chemical

Dirk K. Morr, Alexander V. Balatsky

We argue that the results of recent scanning tunneling microscopy, angle-resolved photoemission and infrared spectroscopy experiments on the CuO chains of YBa$_2$Cu$_3$O$_{6+x}$ are consistently explained within a proximity model by the interplay of a coherent chain-plane and an incoherent interchain coupling. We show that the CuO$_2$ planes act as an ohmic

RC Ball, R Blumenfeld

The transmission of stress through a marginally stable granular pile in two dimensions is exactly formulated in terms of a vector field of loop forces, and thence in terms of a single scalar potential. The loop force formulation leads to a local constitutive equation coupling the stress tensor to {\it fluctuations} in the local geometry. For a disordered pil

J. E. de Freitas, L. S. Lucena, L. R. da Silva, H. J. Hilhorst

Our recent Monte Carlo results [Phys. Rev. E 61 (2000) 6330] for the one-dimensional reaction-diffusion process A+B->2B and B->A lead to the correlation length exponent estimate nu=2.21 +/- 0.05. In a comment on our work [cond-mat/0007366] the exact value is claimed to be nu=2. We reply that the arguments advanced in the comment fail to prove the claim.

Veronica I. Marconi, Daniel Dominguez

We study the non-equilibrium dynamical regimes of a moving vortex lattice in the periodic pinning of a Josephson junction array (JJA) for {\it finite temperatures} in the case of a fractional or submatching field. We obtain a phase diagram for the current driven JJA as a function of the driving current I and temperature T. We find that when the vortex lattic

Kirill Katsov, John D. Weeks

We derive an exact equation for density changes induced by a general external field that corrects the hydrostatic approximation where the local value of the field is adsorbed into a modified chemical potential. Using linear response theory to relate density changes self-consistently in different regions of space, we arrive at an integral equation for a hard

Joachim Hermisson, Holger Wagner, Michael Baake

A variety of selection-mutation models for DNA (or RNA) sequences, well known in molecular evolution, can be translated into a model of coupled Ising quantum chains. This correspondence is used to investigate the genetic variability and error threshold behaviour in dependence of possible fitness landscapes. In contrast to the two-state models treated hithert

Y. Moreno, J. B. Gomez, A. F. Pacheco

Using the global fiber bundle model as a tractable scheme of progressive fracture in heterogeneous materials, we define the branching ratio in avalanches as a suitable order parameter to clarify the order of the phase transition occurring at the collapse of the system. The model is analyzed using a probabilistic approach suited to smooth fluctuations. The br

Alexander I. Olemskoi, Alexei V. Khomenko

Self-organizing system is studied whose behavior is governed by field of an order parameter, a fluctuation amplitude of conjugate field and a couple of Grassmannian conjugated fields that define the entropy as a control parameter. Within the framework of self-consistent approach the dependencies of macro- and microscopic susceptibilities as well as memory an

C. Simserides, U. Hohenester, G. Goldoni, E. Molinari

We investigate theoretically the spatial dependence of the linear absorption spectra of single and coupled semiconductor quantum dots, where the strong three-dimensional quantum confinement leads to an overall enhancement of Coulomb interaction and, in turn, to a pronounced renormalization of the excitonic properties. We show that -because of such Coulomb co

T. Fukui

A fermion model with random on-site potential defined on a two-dimensional square lattice with $π$-flux is studied. The continuum limit of the model near the zero energy yields Dirac fermions with random potentials specified by four independent coupling constants. The basic symmetry of the model is time-reversal invariance. Moreover, it turns out that the mo

M. Golosovsky, Y. Saado, D. Davidov

We report an experimental study of 2D dipole clusters formed by small magnetic particles floating at the air-water interface. The particles form hexagonally ordered clusters due to interplay between dipole-dipole repulsion and confining external forces. Optical images of the clusters allow determination of area S, total energy E, and the chemical potential f

I. K. Yanson

The point-contact spectroscopy, in contrast to the tunneling spectrocopy, considers small electrical contacts with direct conductivity. In the normal state, it enables one to measure the spectral function of electron-boson interaction. In the superconducting state, new features appear connected with the energy dependence of excess current. The non-linearitie

Eli Michael, Richard McCray, C. S. J. Pun, Peter Garnavich

We present ultraviolet and optical spectra of the first bright spot (PA = 29 degrees) on Supernova 1987A's equatorial circumstellar ring taken with the Space Telescope Imaging Spectrograph. We interpret this spot as the emission produced by radiative shocks that occur where the supernova blast wave strikes an inward protrusion of the ring. The observed l

S. Matt, B. Balick, R. Winglee, A. Goodson

We present a simple, robust mechanism by which an isolated star can produce an equatorial disk. The mechanism requires that the star have a simple dipole magnetic field on the surface and an isotropic wind acceleration mechanism. The wind couples to the field, stretching it until the field lines become mostly radial and oppositely directed above and below th

D. Alloin, E. Pantin, P. O. Lagage

We present diffraction-limited IR images at 11.2 and 20.5 microns of the central 6''x6'' region in NGC 1068, collected with the CAMIRAS instrument mounted at the f/36 IR focus of the CFHT/Hawaii 3.6m telescope and at the f/35 IR focus of the ESO/La Silla 3.6m telescope, respectively. After deconvolution, the achieved resolution (0.6''

S. Colafrancesco, B. Mele

We assume that the supersymmetric lightest neutralino is a good candidate for the CDM and explore the possibility to produce diffuse radio emission from high-energy electrons arising from the neutralino annihilation in galaxy clusters whose intracluster medium is filled with a large-scale magnetic field. We show that these electrons fit the population of see

Nathan C. Hearn, Susan A. Lamb

Colliding galaxies are excellent laboratories for studying galactic evolution and global star formation. Computer simulations of galaxy collisions, in which at least one galaxy has a significant gaseous component, show the production of density enhancements and shock waves in the interstellar medium. These high-density regions coincide with the locations of

Michael D. Smith, Mordecai-Mark Mac Low, Fabian Heitsch

Supersonic turbulence generates distributions of shock waves. Here, we analyse the shock waves in three-dimensional numerical simulations of uniformly driven supersonic turbulence, with and without magnetohydrodynamics and self-gravity. We can identify the nature of the turbulence by measuring the distribution of the shock strengths. We find that uniformly d

J. A. Munoz, E. E. Falco, C. S. Kochanek, J. Lehar

We report the discovery of a new two-image gravitational lens candidate. The system RX J0921+4529 contains two z_s=1.66 quasars separated by 6."93 with an H band magnitude difference of $Δm=1.39$. The HST NIC2 H band images reveal an H=18.2 spiral galaxy between the quasar images, which is probably a member of a z_l=0.32 X-ray cluster centered on the fie

Charu Ratnam, Paolo Salucci

We use high-spatial resolution ($\sim 100 pc$) rotation curves of 83 spiral galaxies to investigate the mass distribution of their innermost kpc. We show that, {\it in this region}, the luminous matter completely accounts for the gravitational potential and no dark component is required. The derived I-band disk mass-to-light ratios agree well with those obta

V. P. Reshetnikov, N. Ya. Sotnikova

Numerical simulations of the disruption of a dwarf companion moving in the polar plane of a massive galaxy are presented. The constructed model is compared with observational data on the recently discovered low-surface-brightness stellar ring around galaxy NGC 5907. Constraints on the ring lifetime (<=1.5 gyr after the first approach of the galaxies), on the

Reinhard Genzel

High spatial resolution, near-infrared imaging and spectroscopy of the nuclear star cluster have given key new insights about the dynamics, evolution and mass distribution in the Milky Way Center. The central parsec is powered by a cluster of hot, massive stars which must have formed a few million years ago. Either star formation was triggered in the central

Jonathan L. Feng, Konstantin T. Matchev, Frank Wilczek

Dark matter candidates arising in models of particle physics incorporating weak scale supersymmetry may produce detectable signals through their annihilation into neutrinos, photons, or positrons. A large number of relevant experiments are planned or underway. The `logically possible&#39; parameter space is unwieldy. By working in the framework of minimal su

Jeffrey A. Harvey, Per Kraus, Finn Larsen

We show that the tensionless branes found recently on non-BPS D-branes using non-commutative field theory are in fact gauge equivalent to the vacuum under a discrete gauge symmetry. We also give a simple construction of the D(2p)-branes in IIA theory starting from a single non-BPS D9-brane.

M. Gunaydin, K. Koepsell, H. Nicolai

We present a nonlinear realization of E_8 on a space of 57 dimensions, which is quasiconformal in the sense that it leaves invariant a suitably defined ``light cone&#39;&#39; in 57 dimensions. This realization, which is related to the Freudenthal triple system associated with the unique exceptional Jordan algebra over the split octonions, contains previous c

Muoi Tran, M. V. N. Murthy, R. K. Bhaduri

We consider a small and fixed number of fermions (bosons) in a trap. The ground state of the system is defined at T=0. For a given excitation energy, there are several ways of exciting the particles from this ground state. We formulate a method for calculating the number fluctuation in the ground state using microcanonical counting, and implement it for smal

Alexey Anisimov, Michael Dine

Motivated by recent developments, we explore some issues in Affleck-Dine baryogenesis. We consider in greater detail the role of thermal effects in the production of baryon number. We find that these effects are important even for rather flat potentials, and obtain somewhat different estimates of the baryon asymmetry than those in the literature. We also con

H. Lu, C. N. Pope

We show that four-dimensional N=2 ungauged Einstein-Maxwell supergravity can be embedded on the Randall-Sundrum 3-brane, as a consistent Kaluza-Klein reduction of five-dimensional N=4 gauged supergravity. In particular, this allows us to describe four-dimensional Reissner-Nordstrom black holes within the Randall-Sundrum scenario. Using earlier results on the

A. Bossard, N. Mohammedi

We study the symmetry of the one-loop effective action of bosonic string theory under non-Abelian T-duality transformations. It is shown that the original Lagrangian and its dual are proportional. This result implies that the corresponding reduced low energy effective actions are equivalent and leads to a functional relation between the Weyl anomaly coeffici

Guido Cognola, Sergio Zerbini

The issue related to the so-called dimensional reduction procedure is revisited within the Euclidean formalism. First, it is shown that for symmetric spaces, the local exact heat-kernel density is equal to the reduced one, once the harmonic sum has been succesfully performed. In the general case, due to the impossibility to deal with exact results, the short

Thomas F. George, A. K. Popov

An inversionless gain of anti-Stokes radiation above the oscillation threshold in an optically-dense far-from-degenerate double-Lambda Doppler-broadened medium accompanied by Stokes gain is predicted. The outcomes are illustrated with numerical simulations applied to sodium dimer vapor. Optical switching from absorption to gain via transparency controlled by

N. Aizawa

A new non-standard deformation of all types of classical Lie algebras is constructed by means of Drinfel&#39;d twist based on a six dimensional subalgebra. This is an extension of extended twists introduced by Kulish et al. For the algebra M_3 = so(3,2), a relation to a known non-standard deformation is discussed.

Roberto Iengo, Jussi Kalkkinen

We consider four-graviton scattering in Type II string theory on one-loop level in the large centre of mass energy M^2 limit. We extract from it an explicit integral expression for the full string theory corrections to the imaginary part of the mass-shift and the lifetime of a massive state with the highest allowed spin J=2M^2+2. We find a decay rate that is

M. Caldarelli, G. Catelani, L. Vanzo

The boundary terms in the Hamiltonian, in the presence of horizons, are carefully analyzed in a simple 2D theory admitting AdS black holes. The agreement between the euclidean approach and Cardy&#39;s formula is obtained modulo certain assumptions on the spectrum of the Virasoro&#39;s algebra. There is no discrepancy factor &#34;square root of 2&#34; once th

Joe Sato

We reconsider the meaning of observing CP violation in neutrino oscillation.

Ken Kawahigashi, Kimiaki Nishida, Atsushi Itabashi, Munetake Ichimura

We present a formalism of distorted wave impulse approximation (DWIA) for analyzing spin observables in nucleon inelastic and charge exchange reactions leading to the continuum. It utilizes response functions calculated by the continuum random phase approximation (RPA), which include the effective mass, the spreading widths and the Δdegrees of freedom. The F

A. Micu, M. M. Sheikh-Jabbari

We study perturbative aspects of noncommutative field theories. This work is arranged in two parts. First, we review noncommutative field theories in general and discuss both canonical and path integral quantization methods. In the second part, we consider the particular example of noncommutative $Φ^4$ theory in four dimensions and work out the corresponding

A. Gokalp, O. Yilmaz

We study the $ω\toππγ$ decays by adding to the amplitude calculated within the framework of chiral perturbation theory and vector meson dominance the amplitude of $σ$-meson intermediate state. We estimate the coupling constant $g_{ωσγ}$ utilizing the experimental value of the $ω\toπ^{0}π^{0}γ$ decay rate.

L. Benfatto, S. Caprara, C. Castellani, A. Paramekanti

We study the effect of dissipation on quantum phase fluctuations in d-wave superconductors. Dissipation, arising from a nonzero low frequency optical conductivity which has been measured in experiments below $T_c$, has two effects: (1) a reduction of zero point phase fluctuations, and (2) a reduction of the temperature at which one crosses over to classical

Toshiyuki Fukushige, Junichiro Makino

We investigate the structure of the dark matter halo formed in the cold dark matter scenario using $N$-body simulations. We simulated 12 halos with the mass of $6.6\times 10^{11}M_{\odot}$ to $8.0\times 10^{14}M_{\odot}$. In almost all runs, the halos have density cusps proportional to $r^{-1.5}$ developed at the center, which is consistent with the results

Jian-Min Wang, Ye-Fei Yuan, Mei Wu, Masaaki Kusunose

There is increasing evidence for the presence of an optically thin advection-dominated accretion flow (ADAF) in low luminosity active galactic nuclei and radio-loud quasars. The present paper is devoted to explore the fate of a blob ejected from an ADAF, and to discuss its observational consequences. It is inevitable for the ejected blob to drastically expan

Muge Boz

In this work, we adress the phenomenological consequences of explicit CP violation on direct Higgs-boson searches at high energy colliders. Having a restricted parameter space, we concentrate on the recently proposed gluino-axion model, and investigate the CP violation capability of the model subject to the recent experimental data. It is shown that the Higg

Rob Schneiderman, Peter Teichner

This is the beginning of an obstruction theory for deciding whether a map f:S^2 --> X^4 is homotopic to a topologically flat embedding, in the presence of fundamental group and in the absence of dual spheres. The first obstruction is Wall&#39;s self-intersection number mu(f) which tells the whole story in higher dimensions. Our second order obstruction tau(f

Vladimir Privman, Jongsoon Park

In many applications, transport of particles can be described by the diffusion equation, or its convective-diffusion generalizations, in part of three-dimensional space. In particular, in surface deposition or in growth of aggregates or sediments, particles in the suspension outside the surface or aggregate boundary can be considered as diffusing under the i

Paul J. Werbos, Ludmila Dolmatova

The classic paper of Clauser et al proved that Bell&#39;s Theorem experiments rule out all theories of physics which assume locality, time-forwards causality and the existence of an objective real world. The Backwards-Time Interpretation (BTI) tries to recover realism and locality by permitting backwards time causality. BTI should permit dramatic simplificat

H. K. Cummins, J. A. Jones

We describe novel composite pulse sequences which act as general rotors and thus are suitable for nuclear magnetic resonance (NMR) quantum computation. The Resonance Offset Tailoring To Enhance Nutations (ROTTEN) approach permits perfect compensation of off-resonance errors at two selected frequencies placed symmetrically around the frequency of the RF sourc

Thomas G. Draper

A new method for computing sums on a quantum computer is introduced. This technique uses the quantum Fourier transform and reduces the number of qubits necessary for addition by removing the need for temporary carry bits. This approach also allows the addition of a classical number to a quantum superposition without encoding the classical number in the quant

John L. Bohn

The collisional stability of ultracold polar molecules in electrostatic traps is considered. Rate constants for collisions that drive molecules from weak-field-seeking to strong-field-seeking states are estimated using a simple model. The rates are found to be quite large, of order 10^{-12} - 10^{-10} cm^3/sec, and moreover to grow rapidly in an externally a

Malvin C. Teich, Steven B. Lowen, Bradley M. Jost, Karin Vibe-Rheymer

We focus on various measures of the fluctuations of the sequence of intervals between beats of the human heart, and how such fluctuations can be used to assess the presence or likelihood of cardiovascular disease. We examine sixteen such measures and their suitability for correctly classifying heartbeat records of various lengths as normal or revealing the p

L. V. Kravchuk, G. V. Romanov, S. G. Tarasov

The simulation code has been developed to investigate possible electron multi- pacting in the 3D RF cavities using preliminary calculated field components. The code provides different options of numerical study of the electron multi- pacting including search of the resonant trajectories and simulation of an electron multiplication.

Daniel M. Kaplan, Edgar L. Black, Kevin W. Cassel, Mary Anne Cummings

We describe the program of research and development being undertaken by a consortium of Illinois university groups to develop liquid-hydrogen energy absorbers for muon-beam cooling for a possible stored-muon-beam neutrino factory.

D. P. Roy

One of the greatest achievements of twentieth century physics is the discovery of a very close link between the microcosm and the macrocosm. This follows from the two basic principles of quantum mechanics and relativity, the uncertainty principle and the mass energy equivalence, along with the standard big bang model of cosmology. As we probe deeper into the

W. Xu

We have measured the transverse asymmetry from inclusive scattering of longitudinally polarized electrons from polarized 3He nuclei at quasi-elastic kinematics in Hall A at Jefferson Lab with high statistical and systematic precision. The neutron magnetic form factor was extracted based on Faddeev calculations with an experimental uncertainty of less than 2

R. D&#39;Hulst, G. J. Rodgers

We present a model describing the competition between information transmission and decision making in financial markets. The solution of this simple model is recalled, and possible variations discussed. It is shown numerically that despite its simplicity, it can mimic a size effect comparable to a crash. Two extensions of this model are presented that allow

Hendrik Grundling, Fernando Lledo

We analyze the situation of a local quantum field theory with constraints, both indexed by the same set of space-time regions. In particular we find ``weak&#39;&#39; Haag-Kastler axioms which will ensure that the final constrained theory satisfies the usual Haag-Kastler axioms. Gupta-Bleuler electromagnetism is developed in detail as an example of a theory w

Ariel Caticha

Dynamics, the study of change, is normally the subject of mechanics. Whether the chosen mechanics is ``fundamental&#39;&#39; and deterministic or ``phenomenological&#39;&#39; and stochastic, all changes are described relative to an external time. Here we show that once we define what we are talking about, namely, the system, its states and a criterion to dis

Ariel Caticha

The method of maximum entropy (ME) is extended to address the following problem: Once one accepts that the ME distribution is to be preferred over all others, the question is to what extent are distributions with lower entropy supposed to be ruled out. Two applications are given. The first is to the theory of thermodynamic fluctuations. The formulation is ex

M. Niedermaier, H. Samtleben

We give a brief review on the use of Bethe ansatz techniques to construct solutions of recursive functional equations which emerged in a bootstrap approach to the quantum Ernst system. The construction involves two particular limits of a rational Bethe ansatz system with complex inhomogeneities. First, we pinch two insertions to the critical value. This link

Murray Gerstenhaber, Anthony Giaquinto, Mary E. Schaps

The Donald--Flanigan problem for a finite group H and coefficient ring k asks for a deformation of the group algebra kH to a separable algebra. It is solved here for dihedral groups and for the classical Weyl groups (whose rational group algebras are also computed), leaving but six finite reflection groups with solutions unknown. We determine the structure o

D. Alpay, T. Constantinescu, A. Dijksma, J. Rovnyak

Realization theory for operator colligations on Pontryagin spaces is used to study interpolation and factorization in generalized Schur classes. Several criteria are derived which imply that a given function is almost the restriction of a generalized Schur function. The role of realization theory in coefficient problems is also discussed.

J. Böckenhauer, D. E. Evans

In this lecture we explain the intimate relationship between modular invariants in conformal field theory and braided subfactors in operator algebras. Our analysis is based on an approach to modular invariants using braided sector induction (&#34;$α$-induction&#34;) arising from the treatment of conformal field theory in the Doplicher-Haag-Roberts framework.

L. Brambila Paz, E. Gomez Gonzalez, F. Pioli

We study the birationality (onto its image) of the Abel-Prym morphism associated with a Prym-Tuyrin variety. We use such result to prove that Picard bundles over Prym varieties are simple and moreover they are stable when the Abel-Prym morphism is not birational. As a consequence we obtain that Picard bundles over moduli spaces of stable vector bundles with

S. V. Astashkin

We present necessary and sufficient conditions on systems of random variables for them to possess a lacunary subsystem equivalent in distribution to the Rademacher system on the segment [0,1]. In particular, every uniformly bounded orthonormal system has this property. Furthermore, an arbitrary finite uniformly bounded orthonormal set of N functions contains

Yoram Louzoun, Irun. R. Cohen, Henri Atlan

Following previous models describing a quasi steady state (QSS) for the evolution of HIV infection and AIDS, we have developed a larger formalism simulating the long-term evolution of the QSS We show that the long-term evolution of AIDS cannot be explained by the destruction alone of CD4 T cells, either directly or indirectly. The destruction of CD4 T cells

Tanguy Rivoal

We provide a lower bound for the dimension of the vector space spanned by 1 and by the values of the Riemann Zeta function at the first odd integers. As a consequence, the Zeta function takes infinitely many irrational values at odd integers.

Roger Carter, Bethany Marsh

Let U_q be the quantum group associated to a Lie algebra g of rank n. The negative part U^- of U has a canonical basis B with favourable properties, introduced by Kashiwara and Lusztig. The approaches of Kashiwara and Lusztig lead to a set of alternative parametrizations of the canonical basis, one for each reduced expression for the longest word in the Weyl

Konstantin Salikhov

Let $f:V^n\looparrowright M^m$ be a smooth generic immersion. Then the set of points, that have at least $k$ preimages is an image of a (non-generic) immersion. If the manifolds $V^n$ and $M^m$ are oriented and $m-n$ is even, then the manifold of $k$-fold points is also oriented. In this paper we compute the oriented bordism class of the manifold of $k$-fold

Annette Werner

This paper generalizes Manin&#39;s approach towards a geometrical interpretation of Arakelov theory at infinity to linear cycles on projective spaces. We show how to interpret certain non-Archimedean Arakelov intersection numbers of linear cycles on $P^{n-1}$ with the combinatorial geometry of the Bruhat-Tits building associated to PGL(n). This geometric set

C. Anantharaman-Delaroche

In this survey, we study the relations between amenability (resp. amenability at infinity) of C*-dynamical systems and equality or nuclearity (resp. exactness) of the corresponding crossed products.

Vestislav Apostolov, Paul Gauduchon

We provide a local classification of self-dual Einstein Riemannian four manifolds admitting a positively oriented Hermitian structure and characterize those which carry a hyperhermitian, non-hyperkählerian structure compatible with the negative orientation. We finally show that self-dual Einstein 4-manifolds obtained as quaternionic quotients of the Wolf spa

Marcelo De Francia, Klaus Kirsten, J. S. Dowker

As a technical exercise with possible relevance to the holographic principle and string theory, the effective actions (functional determinants) for scalars and spinors on the squashed three-sphere identified under the action of a cyclic group, Z_m, are determined. Especially in the extreme oblate squashing limit, which has a thermodynamic interpretation, the

P. Bozhilov

We show how the classical string dynamics in $D$-dimensional curved background can be reduced to the dynamics of a massless particle constrained on a certain surface whenever there exists at least one Killing vector for the background metric. Then we obtain a number of sufficient conditions, which ensure the existence of exact solutions to the equations of m

Thomas Wynter

We investigate the physical metric seen by a D0-brane probe in the background geometry of an N=2 sigma model. The metric is evaluated by calculating the Zamolodchikov metric for the disc two point function of the boundary operators corresponding to the displacement of the D0-brane boundary. At two loop order we show that the D0 metric receives an $R^2$ contr

U. Baur, D. Rainwater

A detailed analysis of ZZ production at the upgraded Fermilab Tevatron and the CERN Large Hadron Collider is presented for general ZZZ and ZZγcouplings. Deviations from the Standard Model gauge theory structure for each of these can be parameterized in terms of two form factors which are severely restricted by unitarity at high energy. Achievable limits on t

A. Babansky, I. Balitsky

There are two sources of the factorial large-order behavior of a typical perturbative series. First, the number of the different Feynman diagrams may be large; second, there are abnormally large diagrams known as renormalons. It is well known that the large combinatorial number of diagrams is described by instanton-type solutions of the classical equations.

Howard Baer, Csaba Balazs, Pedro Mercadante, Xerxes Tata

Supersymmetric models with an inverted mass hierarchy (IMH: multi-TeV first and second generation matter scalars, and sub-TeV third generation and Higgs scalars) have been proposed to ameliorate phenomenological problems arising from flavor changing neutral currents (FCNCs) and CP violating processes, while satisfying conditions of naturalness. Models with a