September 2000 arXiv papers — page 12

Finn Ravndal

A critical look is taken at the calculation of the Casimir effect. The boundary conditions play an important role and should be imposed in a physical way. An acceptable result for the vacuum energy is only obtained when different regularization schemes yield the same result. Radiative corrections to the Casimir force between two parallel plates due to electr

A. Rusetsky

Recent progress in the description of the properties of hadronic atoms on the basis of non-relativistic effective Lagrangian approach and Chiral Perturbation Theory (ChPT) is reported. For the case of the pi(+)pi(-) atom decay, the problem is completely solved, both conceptually and numerically. For the pi(-)p atom, a general expression for the ground-state

V. E. Lyubovitskij, A. Rusetsky

The general formula of the pi(-)p atom strong energy-level shift in the 1s state is derived in the next-to-leading order in the isospin breaking, and in all orders in chiral expansion. Isospin-breaking corrections to the level shift are explicitly evaluated at order p^2 in ChPT. The results clearly demonstrate the necessity to critically reaccess the values

David Elazzar Kaplan, Graham D. Kribs

We present a model of supersymmetry breaking mediated through a small extra dimension. Standard model matter multiplets and a supersymmetry-breaking (or ``hidden'') sector are confined to opposite four-dimensional boundaries while gauge multiplets live in the bulk. The hidden sector does not contain a singlet and the dominant contribution to gaugino

Eizou Umezawa

We consider what occurs when we remove one of the compositeness conditions proposed by Bardeen, Hill and Lindner that leads to predictions for the top quark mass conflicting with the experimental value. Through this consideration the condition for the Higgs particle to be the composite particle is reconsidered. We show that in this case, (I) the Higgs-Yukawa

Matthew Wingate

Values for the strange quark mass and average up/down mass have been obtained from quenched lattice QCD simulations using the domain wall fermion action. This discretization preserves the properties of flavor and chiral symmetry at nonzero lattice spacing. Results are shown for two values of the lattice spacing. The mass renormalization constant is computed

F. Di Renzo

The first ten coefficients in the perturbative expansion of the plaquette in Lattice SU(3) are computed both on a 8^4 and on a 24^4 lattice. They are shown to be fully consistent with the growth dictated by the first IR Renormalon and with the expected finite size effects on top of that. As already pointed out a few years ago, this leads to a puzzling result

Matthew D. Duez, Thomas W. Baumgarte, Stuart L. Shapiro

We present a new method for generating the nonlinear gravitational wavetrain from the late inspiral (pre-coalescence) phase of a binary neutron star system by means of a numerical evolution calculation in full general relativity. In a prototype calculation, we produce 214 wave cycles from corotating polytropes, representing the final part of the inspiral pha

X. Martin, D. O'Connor, D. P. Rideout, R. D. Sorkin

We study the ``renormalization group action'' induced by cycles of cosmic expansion and contraction, within the context of a family of stochastic dynamical laws for causal sets derived earlier. We find a line of fixed points corresponding to the dynamics of transitive percolation, and we prove that there exist no other fixed points and no cycles of l

Ion Androutsopoulos, Georgios Paliouras, Vangelis Karkaletsis, Georgios Sakkis

We investigate the performance of two machine learning algorithms in the context of anti-spam filtering. The increasing volume of unsolicited bulk e-mail (spam) has generated a need for reliable anti-spam filters. Filters of this type have so far been based mostly on keyword patterns that are constructed by hand and perform poorly. The Naive Bayesian classif

Erik F. Tjong Kim Sang, Sabine Buchholz

We describe the CoNLL-2000 shared task: dividing text into syntactically related non-overlapping groups of words, so-called text chunking. We give background information on the data sets, present a general overview of the systems that have taken part in the shared task and briefly discuss their performance.

Akihisa Koga

We investigate quantum phase transitions in the three-dimensional orthogonal-dimer system of the compound $\rm SrCu_2(BO_3)_2$ by means of the series expansion technique. We then discuss the phase diagram where the dimer phase, the Haldane phase, the frustration-induced disordered phase and the magnetically ordered phase compete with each other. It is found

R. Siddharthan, B. S. Shastry, A. P. Ramirez

We take another look at two compounds which have been discussed as possible realizations of ``spin ice'', namely holmium titanate and dysprosium titanate. As we have earlier observed, holmium titanate does not display ice-like behaviour at low temperatures because the long ranged dipolar interactions between spins are strong compared to the nearest n

Rosa Lopez, Ramon Aguado, Gloria Platero, Carlos Tejedor

We present a fully nonequilibrium calculation of the low temperature transport properties of a quantum dot in the Kondo regime when an AC potential is applied to the gate voltage. We solve a time dependent Anderson model with finite on-site Coulomb interaction. The interaction self-energy is calculated up to second order in perturbation theory in the on-site

M. Himmerich, M. Letz

We derive simplified Faddeev type equations for the three particle T-matrix which are valid in the Hubbard model where only electrons with opposite spins interact. Using the approximation of dynamical mean field theory these equations are partially solved numerically for the attractive Hubbard model. It is shown that the three particle T-matrix contains a te

Andrea Crisanti, Felix Ritort

In this talk we discuss the possibility of constructing a fluctuation theory for structural glasses in the non-equilibrium aging state. After reviewing well known results in a toy model we discuss some of the key assumptions which support the validity of this theory, in particular the role of the configurational entropy and its relation to the effective temp

E. Bacry, J. Delour, J. F. Muzy

In this paper we briefly review the recently inrtroduced Multifractal Random Walk (MRW) that is able to reproduce most of recent empirical findings concerning financial time-series : no correlation between price variations, long-range volatility correlations and multifractal statistics. We then focus on its extension to a multivariate context in order to mod

Pierre-Gilles de Gennes

This paper is extracted from an opening address given at the workshop "Wetting: from microscopic origins to industrial applications" (Giens, May 6-12, 2000). It discusses two special points a) the nature of line energies for a contact line b) the aging of emulsions.

J. I. Martin, M. Velez, A. Hoffmann, I. K. Schuller

Pinning interactions between superconducting vortices in Nb and magnetic Ni dots were studied as a function of current and temperature to clarify the nature of pinning mechanisms. A strong current dependence is found for a square array of dots, with a temperature dependent optimum current for the observation of periodic pinning, that decreases with temperatu

V. Shahrezaei, M. R. Ejtehadi

By enumerating all sequences of length 20, we study the designability of structures in a two-dimensional Hydrophobic-Polar (HP) lattice model in a wide range of inter-monomer interaction parameters. We find that although the histogram of designability depends on interaction parameters, the set of highly designable structures is invariant. So in the HP lattic

G. Ravikumar

We present a phenomenological model for the vortex dynamics in the peak effect region of weakly pinned superconductors. We explain the history dependent dynamic response of the metastable vortex states subjected to a transport current and the hysteretic voltage-current characteristics observed in the vicinity of peak effect in weakly pinned superconductors.

Pierre Lombardo, Gilbert Albinet

We have investigated electronic properties of the degenerate multi-orbital Hubbard model, in the limit of large spatial dimension. A new local model, including a doubly degenerate strongly correlated site has been introduced and solved in the framework of the non-crossing approximation (NCA). Mott-Hubbard transitions have been examined in details, including

Kunihiko Kaneko, Tetsuya Yomo

A novel mechanism for sympatric speciation that takes into account complex bio-processes within each individual organism is proposed. According to dynamical systems theory, organisms with identical genotypes can possess differentiated physiological states and may coexist `symbiotically' through appropriate mutual interaction. With mutations, the phenotyp

Beverly J. Smith, Megan Donahue, John Stocke

We present new multi-wavelength data for the NGC 4410 galaxy group. This group contains the peculiar radio galaxy NGC 4410A, which has a distorted double-lobed radio structure. NGC 4410A is strongly interacting with three nearby galaxies, and has a peculiar ring-like optical morphology, a number of luminous H II regions, as well as as tidal tails and bridges

Mauricio Reyes-Ruiz

We examine the linear stability of a flow threaded by a weak, vertical magnetic field in a disk with a keplerian rotation profile and a vertical stratification of the ionization degree as that predicted for vast portions of protoplanetary disks. A quasi-global analysis is carried out, where the form of the perturbations in the vertical direction is determine

D. Gondek-Rosinska, P. Haensel, J. L. Zdunik, E. Gourgoulhon

We study effects of the strange quark mass and of the QCD coupling constant in the MIT bag model of quark matter with lowest order quark-gluon interactions on the rapid rotation of strange stars. The influence of rotation on global parameters of strange stars is greater than in the case of the neutron star models. We show that independently of the strange qu

Glenn E. Ciolek, Shantanu Basu

We review theoretical models of the early stages of star formation, in which gravitational collapse is strongly regulated by magnetic fields and the associated process of ambipolar diffusion. We discuss results of numerical simulations and analytical studies of core formation and collapse, which can be directly tested against observation. We also focus on re

D. A. Hunter, R. W. O'Connell, J. S. Gallagher, T. A. Smecker-Hane

We examine star clusters in the irregular, starburst galaxy NGC 1569 from HST images. In addition to the two known super star clusters, we identify 45 other clusters that are compact but resolved. Integrated UVI colors of the clusters span a large range, and suggest that ages range from 3 Myrs to 1 Gyr. However, most of the clusters were formed at the tail e

M. Prakash

Immediately after they are born, neutron stars are characterized by an entropy per baryon of order unity and by the presence of trapped neutrinos. If the only hadrons in the star are nucleons, these effects slightly reduce the maximum mass relative to cold, catalyzed matter. However, if stangeness-bearing hyperons, a kaon condensate, or quarks are also prese

Peter R Newman

A potential problem with using wide-field multi-object spectrographs for quasar redshift surveys is the introduction of position-dependent selection effects into the survey catalogue because of variations in the observed signal-to-noise ratio (SNR) across the survey area. A function relating signal losses in instruments using optical fibre input to the fibre

Kin-Wang Ng

We study the complex visibilities of the cosmic microwave background anisotropies that are observables in interferometric observations of the cosmic microwave background, using the multipole expansion methods commonly adopted in analyzing single-dish experiments. This allows us to recover the properties of the visibilities that is obscured in the flat-sky ap

Kyoko Matsushita

Statistical properties of X-ray luminosity and temperature are studied for 52 early-type galaxies based on the ROSAT PSPC data. All of the X-ray luminous galaxies show largely extended emission with a radius of a few times of 10$r_e$, while X-ray faint galaxies do not show such a component. This leads to a division of early-type galaxies into two categories:

M. Villar-Martin, A. Alonso-Herrero, S. di Serego Alighieri, J. Vernet

The nature of the extreme kinematics in the extended gas of distant radio galaxies (z>0.7) is still an open question. With the advent of the 8-10 m telescope generation and the development of NIR arrays we are in the position for the first time to develop a more detailed study by using lines other than Lya and [OII]3727 depending on redshift. In this paper w

E. Hatziminaoglou, G. Mathez, A. Manrique

The growth of Super Massive Black Holes and the parallel development of activity in galactic nuclei are implemented in an analytic code of hierarchical clustering. The evolution of the luminosity function of quasars and AGN will be computed with special attention paid to the connection between quasars and Seyfert galaxies. One of the major interests of the m

V. Hill, P. François, M. Spite, F. Primas

We report on the first high-resolution spectroscopy of 10 giants in LMC Globular Clusters in a wide age range, obtained with the newly commissioned spectrograph UVES at VLT UT2. These observations are used to derive oxygen and iron content of these clusters, and the abundances are then used to cast a more precise view, not only on the age-metallicity relatio

Bianca M. Poggianti

The abundance of elliptical, S0 and spiral galaxies in clusters is presented as a function of redshift comparing the results of the HST distant cluster studies with new data at z~0.2 and with the standard local comparison samples. This analysis confirms and strengthens the conclusion that the proportion of S0 galaxies increases toward lower redshifts at the

Alessandro de Angelis

GLAST, a detector for cosmic gamma rays in the range from 20 MeV to 300 GeV, will be launched in space in 2005. Breakthroughs are expected in particular in the study of particle acceleration mechanisms in space and of gamma ray bursts, and maybe on the search for cold dark matter; but of course the most exciting discoveries could come from the unexpected.

Y. Lyubarsky, J. G. Kirk

It is generally thought that most of the spin-down power of a pulsar is carried away in an MHD wind dominated by Poynting flux. In the case of an oblique rotator, a significant part of this energy can be considered to be in a low-frequency wave, consisting of stripes of toroidal magnetic field of alternating polarity, propagating in a region around the equat

Francesca Matteucci

We select and discuss the best observables to be used to constrain models of galactic chemical evolution. To this purpose, we discuss the observables in our Galaxy, which is the best studied system, as well as in external galaxies.

J. Hwang, H. Noh

We consider the evolution of perturbed cosmological spacetime with multiple scalar fields in Einstein gravity. A complete set of scalar-type perturbation equations is presented in a gauge-ready form, and we derived the closed set of second-order differential equations in several useful forms. Conserved behaviors of the perturbed three-space curvature in the

Heon-Young Chang, Chul-Sung Choi, Insu Yi

It has been suggested that optically thin and geometrically thick accretion flows are responsible for the observed radio/X-ray luminosity relation of the X-ray bright galactic nuclei. If this is the case then central supermassive black hole masses can be estimated directly from measurements of the core radio luminosity and the X-ray luminosity, provided that

J. E. Everett, J. M. Weisberg

By fitting the classical Rotating Vector Model (RVM) to high quality polarization data for selected radio pulsars, we find the inclination of the magnetic axis to the spin axis, alpha, as well as the minimum angle between the line of sight and the magnetic axis, beta, for ten objects. We give a full treatment of statistical errors in the fitting process. We

Tianjun Li

We discuss the general models with one time-like extra dimension and parallel 3-branes on the space-time $M^4 \times M^1$. We also construct the general brane models or networks with $n$ space-like and $m$ time-like extra dimensions and with constant bulk cosmological constant on the space-time $M^4\times (M^1)^{n+m}$, and point out that there exist two kind

Ludvig Faddeev, Lisa Freyhult, Antti J. Niemi, Peter Rajan

Shafranov's virial theorem implies that nontrivial magnetohydrodynamical equilibrium configurations must be supported by externally supplied currents. Here we extend the virial theorem to field theory, where it relates to Derrick's scaling argument on soliton stability. We then employ virial arguments to investigate a realistic field theory model of

Peter Markos

We study numerically an electronic transport in strongly anisotropic weakly disorderd two-dimensional systems. We find that the conductance distribution is gaussian but the conductance fluctuations increase when anisotropy becomes stronger. We interpret this result by random matrix theory with non-integer symmetry parameter beta, in accordance with recent th

Sean A. Hartnoll, Eric G. Blackman

The central engines of active galactic nuclei (AGN) contain cold, dense material as well as hot X-ray emitting gas. The standard paradigm for the engine geometry is a cold thin disc sandwiched between hot X-ray coronae. Strong support for this geometry in Seyferts comes from the study of fluorescent iron line profiles, although the evidence is not ubiquitous

Edward R. Floyd

The philosophy of the trajectory representation is contrasted with the Copenhagen and Bohmian philosophies.

S. Wallentowitz, I. A. Walmsley, J. H. Eberly

Accounting for resources is the central issue in computational efficiency. We point out physical constraints implicit in information readout that have been overlooked in classical computing. The basic particle-counting mode of read-out sets a lower bound on the resources needed to implement a quantum computer. As a consequence, computers based on classical w

N. Mosyagin, E. Eliav, U. Kaldor

Convergence problems in coupled-cluster iterations are discussed, and a new iteration scheme is proposed. Whereas the Jacobi method inverts only the diagonal part of the large matrix of equation coefficients, we invert a matrix which also includes a relatively small number of off-diagonal coefficients, selected according to the excitation amplitudes undergoi

Alan McKane, David Alonso, Ricard V. Sole

A dynamical model of an ecological community is analyzed within a "mean-field approximation" in which one of the species interacts with the combination of all of the other species in the community. Within this approximation the model may be formulated as a master equation describing a one-step stochastic process. The stationary distribution is obtain

Djordje Minic

We review an approach towards a covariant formulation of Matrix theory based on a discretization of the 11d membrane. Higher dimensional algebraic structures, such as the quantum triple Nambu bracket, naturally appear in this approach. We also discuss a novel geometric understanding of the space-time uncertainty relation which points towards a more geometric

Ulrich Nierste

The calculation of QCD corrections to the width difference Delta Gamma in the B_s meson system is presented. The next-to-leading order corrections reduce the dependence on the renormalization scale significantly and allow for a meaningful use of hadronic matrix elements from lattice gauge theory. At present the uncertainty of the lattice calculations limits

Arash Mafi, Stuart Raby

In this paper we present a solution to the $μ$ problem in an SO(10) supersymmetric grand unified model with gauge mediated and D-term supersymmetry breaking. A Peccei-Quinn symmetry is broken at the messenger scale $M\sim 10^{12}$ GeV and enables the generation of the $μ$ term. The boundary conditions defined at $M$ lead to a phenomenologically acceptable ve

Maria Krawczyk, Jan Zochowski, Peter Mattig

The sensitivity to a light Higgs boson in the general 2HDM (II), with a mass below 40 GeV, is estimated for an future e+e- linear collider operating with very high luminosity at the Z peak (GigaZ). We consider a possible Higgs boson production via the Bjorken process, the (hA) pair production, the Yukawa process Z -> b {\bar b} h(A), -> tau {\bar tau} h(A),

Kaoru Hagiwara, Shinya Kanemura, Yoshiaki Umeda

One-loop contributions of super-partner particles to $W$-pair production at $e^+e^-$ collision are discussed in the MSSM. To obtain trustworthy results we test our calculation using three methods: (1) sum rules among form factors which result from the BRS invariance, (2) the decoupling theorem, (3) the high-energy stability. We examine the corrections taking

Tulsi Dass, Yogesh N. Joglekar

The formalism for histories-based generalized quantum mechanics developed in two earlier papers is applied to the treatment of histories (of particles or fields or more general objects) in curved spacetimes (which need not admit foliation in spacelike hypersurfaces). The construction of the space of temporal supports (a partial semigroup generalizing the spa

Tulsi Dass, Yogesh N. Joglekar

Symmetries are defined in histories-based generalized quantum mechanics paying special attention to the class of history theories admitting quasitemporal structure (a generalization of the concept of `temporal sequences' of `events' using partial semigroups) and logic structure for `single time histories'. Symmetries are classified into orthochro

Jorge Pullin

Research Briefs: Cosmic microwave background anisotropy experiments, by Sean Carroll LISA Project Update by Bill Folkner An update on the r-mode instability, by Nils Andersson Laboratory experiments: news from MG9, by Riley Newman Progress toward Commissioning the LIGO detectors, by Stan Whitcomb 160 Hours of Data Taken on TAMA300, by Seiji Kawamura Conferen

Sean C. Ahern, John W. Norbury, William J. Poyser

We study the feasibility of producing the graviton of the novel Kaluza-Klein theory in which there are d large compact dimensions in addition to the 4 dimensions of Minkowski spacetime. We calculate the cross section for producing such a graviton in nucleus-nucleus collisions via t-channel photon-photon fusion using the semiclassical Weizsacker-Williams meth

Izabela Szlufarska, Arkadiusz Wojs, John J. Quinn

We study photoluminescence (PL) of charged excitons ($X^-$) in narrow asymmetric quantum wells in high magnetic fields B. The binding of all $X^-$ states strongly depends on the separation $δ$ of electron and hole layers. The most sensitive is the ``bright'' singlet, whose binding energy decreases quickly with increasing $δ$ even at relatively small

Peter Markos

We show that the random matrix theory with non-integer "symmetry parameter" beta describes the statistics of transport parameters of strongly disordered two dimensional systems.

David N. Burrows, Eli Michael, Una Hwang, Richard McCray

We present high resolution Chandra observations of the remnant of SN1987A in the Large Magellanic Cloud. The high angular resolution of the Chandra X-ray Observatory (CXO) permits us to resolve the X-ray remnant. We find that the remnant is shell-like in morphology, with X-ray peaks associated with some of the optical hot spots seen in HST images. The X-ray

G. I. Ogilvie, G. Dubus

We study the radiation-driven warping of accretion discs in the context of X-ray binaries. The latest evolutionary equations are adopted, which extend the classical alpha theory to time-dependent thin discs with non-linear warps. We also develop accurate, analytical expressions for the tidal torque and the radiation torque, including self-shadowing. We inves

Prasanta K. Tripathy, Avinash Khare

We consider self-duality in a 2+1 dimensional gauge theory containing both the Born-Infeld and the Chern-Simons terms. We introduce a Born-Infeld inspired generalization of the Proca term and show that the corresponding self dual equation is identical to that of the Born-Infeld-Chern-Simons theory.

A. Y. Potekhin, G. Chabrier

The analytic equation of state of nonideal Coulomb plasmas consisting of pointlike ions immersed in a polarizable electron background (physics/9807042) is improved, and its applicability range is considerably extended. First, the fit of the electron screening contribution in the free energy of the Coulomb liquid is refined at high densities where the electro

V. S. Gerdjikov, G. G. Grahovski, R. I. Ivanov, N. A. Kostov

The reductions of the integrable N-wave type equations solvable by the inverse scattering method with the generalized Zakharov-Shabat systems L and related to some simple Lie algebra g are analyzed. The Zakharov- Shabat dressing method is extended to the case when g is an orthogonal algebra. Several types of one soliton solutions of the corresponding N- wave

Alexander D. Panov

Shrödinger equation for two-step spontaneous cascade transition in a three-level quantum system is solved by means of Markovian approximation for non-Markovian integro-differential evolution equations for amplitudes of states. It is shown that both decay constant and radiation shift of initial level are affected by instability of intermediate level of the ca

Ivan Kondov, Ulrich Kleinekathoefer, Michael Schreiber

The numerical efficiency of different schemes for solving the Liouville-von Neumann equation within multilevel Redfield theory has been studied. Among the tested algorithms are the well-known Runge-Kutta scheme in two different implementations as well as methods especially developed for time propagation: the Short Iterative Arnoldi, Chebyshev and Newtonian p

L. Pienkowski, K. Kwiatkowski, T. Lefort, W. -c. Hsi

Experimental data from the reaction of an 8.0 GeV/c pi- beam incident on a 197Au target have been analyzed in order to investigate the integrated breakup time scale for hot residues. Alpha-particle energy spectra and particle angular distributions supported by a momentum tensor analysis suggest that at large excitation energy, above 3-5 MeV/nucleon, light-ch

V. S. Gerdjikov

The adiabatic N-soliton train interactions for the scalar nonlinear Schrodinger (NLS) equation and its perturbed versions are well studied. Here we briefly outline how they can be generalized for the higher NLS-type equations and for the multicomponent NLS equations. It is shown that in all these cases the complex Toda chain plays fundamental role.

V. S. Gerdjikov, G. G. Grahovski

Reductions of N-wave type equations related to simple Lie algebras and the hierarchy of their Hamiltonian structures are studied. The reduction group G_R is realized as a subgroup of the Weyl group of the corresponding algebra. Some of the reduced equations are of physical interest.

Javid Atai, Boris A. Malomed

We investigate the existence and stability of gap solitons in a double-core optical fiber, where one core has the Kerr nonlinearity and the other one is linear, with the Bragg grating (BG) written on the nonlinear core, while the linear one may or may not have BG. The model considerably extends the previously studied families of BG solitons. For zero-velocit

J. Timmer

Surrogate data testing for linearity is frequently applied to confirm the results of nonlinear time series analysis. We argue that this, in general, is not possible.

Eugene Polulyakh

Theorem converse to Jordan's curve theorem says that {\it if a compact set $K$ has two complementary domains in $R^{2}$, from each of which it is at every point accessible, it is a simple closed curve}. We show that the requirement of this theorem that {\it all} points of $K$ were accessible from {\it both} complementary domains is surplus and prove one

Toke Meier Carlsen

We show that for a sofic shift Lambda, Matsumoto's C*-algebra O_Lambda is isomorphic to the Cuntz-Krieger algebra of the left Krieger cover graph of Lambda.

A. A. Andrianov, V. A. Andrianov, D. Espriu, R. Tarrach

The effective quark models are employed to describe the hadronization of QCD in the quark sector. They reveal a different structure depending on how the spontaneous chiral symmetry breaking (CSB) is implemented. When the generation of light pseudoscalar mesons is manifestly incorporated one deals with an extension of the chiral quark model (CQM) with the non

J. Magnin, L. M. Mendoza-Navas

Experiments on charm hadroproduction have shown a substantial difference in the production of charm and anticharm hadrons. In this work we study /\_c+ and /\_c- inclusive production in p-N interactions in the framework of two component models. We show that the recombination two component model gives a qualitatively and quantitatively good description of /\_c

George W. S. Hou

After briefly reviewing how data indicated that factorization seems to work in observed two body charmless modes, {\it if one takes $γ\gtap 90^\circ$}, we point out that the $K^0π^0$ mode seems too large. This and other hints suggest that perhaps not only $γ$ is large, but rescattering phase $δ$ could be sizable as well.

Seungwon Baek, Toru Goto, Yasuhiro Okada, Ken-ichi Okumura

Flavor changing neutral current and lepton flavor violating processes are studied in the SU(5) SUSY-GUT with right-handed neutrino supermultiplets. Using input parameters motivated by neutrino oscillation, it is shown that the time-dependent CP asymmetry of $b \to s γ$ can be as large as 20%. We also show that the $B_s$-$\bar{B}_s$ mixing can be significantl

I. I. Bigi

After pointing out the amazing success of the CKM description in accommodating the phenomenology of flavour changing neutral currents I review the status of theoretical technologies for extracting CKM parameters from data. I sketch novel directions, namely attempts to deal with quark-hadron duality in a (semi)quantitative way and to develop a QCD description

M. V. Feigel'man

It is shown that disentangled vortex liquid can be a true thermodynamic phase of type-II superconductors in spite of the absense of supercurrent in the direction parallel to the magnetic field.

Valery P. Kisel, Adkham A. Paiziev, Arkady D. Styrkas

The remarkable finding of this work is the linear correlation between the critical temperature of superconducting (SC) transition, Tc, and the room-temperature half-width of angular correlation of positron annihila- tion phonons (ACPAP), Go/2, in the series of powder samples of high-Tc YBCO(123) ceramic superconductors (SCs) with various deficiency of oxygen

N. Vandewalle, F. Brisbois, X. Tordoir

We have analyzed the cross-correlations of daily fluctuations for N=6 358 US stock prices during the year 1999. From those $N(N-1)/2$ correlations coefficients, the Minimum Spanning Tree (MST) has been built. We have investigated the topology exhibited by the MST. Eventhough the average topological number is $<n > \approx 2$, the variance $σ$ of the topologi

Michael W. Deem

An analogy between combinatorial chemistry and Monte Carlo computer simulation is pursued. Examples of how to design libraries for both materials discovery and protein molecular evolution are given. For materials discovery, the concept of library redesign, or the use previous experiments to guide the design of new experiments, is introduced. For molecular ev

Glenn E. Ciolek, Shantanu Basu

We revisit the problem of the formation of dense protostellar cores due to ambipolar diffusion within magnetically supported molecular clouds, and derive an analytical expression for the core formation timescale. The resulting expression is similar to the canonical expression = t_{ff}^2/t_{ni} ~ 10 t_{ni} (where t_{ff} is the free-fall time and t_{ni} is the

Tanya L. Hill, Charlene A. Heisler, Ray P. Norris, John E. Reynolds

It was once common to regard Seyfert and starburst galaxies as completely different types of object, but there is growing recognition that these classifications refer to the extremes of a continuous spectrum of galaxy types. In a previous study we investigated a sample of galaxies with ambiguous optical emission-line ratios and concluded from near-infrared s

V. Barger, Danny Marfatia

We consider the efficacy of using luminosity distance measurements of deep redshift supernovae to discriminate between two forms of dark energy, quintessence (a scalar field with canonical kinetic terms rolling down a potential) and k-essence (a scalar field whose cosmic evolution is driven entirely by non-linear kinetic terms). The primary phenomenological

George Siopsis

We discuss the quantization of a system of slowly-moving extreme Reissner-Nordstrom black holes. In the near-horizon limit, this system has been shown to possess an SL(2,R) conformal symmetry. However, the Hamiltonian appears to have no well-defined ground state. This problem can be circumvented by a redefinition of the Hamiltonian due to de Alfaro, Fubini a

Paulo Aguiar, Paulo Crawford

Following the recent recognition of a positive value for the vacuum energy density and the realization that a simple Kantowski-Sachs model might fit the classical tests of cosmology, we study the qualitative behavior of three anisotropic and homogeneous models: Kantowski-Sachs, Bianchi type-I and Bianchi type-III universes, with dust and a cosmological const

H. Matsumoto, T. G. Tsuru, K. Koyama, H. Awaki

We present results from observations of the most famous starburst galaxy M82 with the High-Resolution Camera onboard the Chandra X-Ray Observatory. We found nine sources in the central 1&#39; x 1&#39; region, but no source was detected at the galactic center. Comparing the observations on 1999 October 28 and on 2000 January 20, we found four of the nine sour

Tomaz Prosen, Thomas H. Seligman, Hans A. Weidenmueller

Many models for chaotic systems consist of joining two integrable systems with incompatible constants of motion. The quantum counterparts of such models have a propagator which factorizes into two integrable parts. Each part can be diagonalized. The two eigenvector bases are related by an orthogonal (or unitary) transformation. We construct a random matrix e

Krzysztof A. Meissner, Marek Olechowski

We consider a class of higher order corrections with arbitrary power $n$ of the curvature tensor to the standard gravity action in arbitrary space-time dimension $D$. The corrections are in the form of Euler densities and are unique at each $n$ and $D$. We present a generating functional and an explicit form of the corresponding conserved energy-momentum ten

Alexander A. Chernitskii

Clifford number formalism for Maxwell equations is considered. The Clifford imaginary unit for space-time is introduced as coordinate independent form of fully antisymmetric fourth-rank tensor. The representation of Maxwell equations in massless Dirac equation form is considered; we also consider two approaches to the invariance of Dirac equation in respect

P. Kosinski, J. Lukierski, P. Maslanka

We consider local field theory on $κ$-deformed Minkowski space which is an example of solvable Lie-algebraic noncommutative structure. Using integration formula over $κ$-Minkowski space and $κ$-deformed Fourier transform we consider for deformed local fields the reality conditions as well as deformation of action functionals in standard Minkowski space. We p

Wolfgang Lucha, Khin Maung Maung, F. F. Schoberl

The Bethe-Salpeter formalism in the instantaneous approximation for the interaction kernel entering into the Bethe-Salpeter equation represents a reasonable framework for the description of bound states within relativistic quantum field theory. In contrast to its further simplifications (like, for instance, the so-called reduced Salpeter equation), it allows

Raffaele Cafiero, Guido Caldarelli

We study, both with numerical simulations and theoretical methods, a cellular automata model for continuum equations describing growth processes in the presence of an external flux of particles. As a result of local instabilities we find a fractal regime of growth for small external fluxes. The growing tip is selected with probability proportional to the cur

M. Kowalski

Accumulation and annihilation of weakly interacting massive particles (WIMPs) in the earth and the sun may be observed by the resulting neutrino signal. We demonstrate that, for certain parts of the SUSY parameter space, present and future neutrino telescopes can expect a higher rate of events due to tau-neutrinos than of events due to muon-neutrinos. We sho

Robert J. C. Spreeuw

An analogous model system for quantum information processing is discussed, based on classical wave optics. The model system is applied to three examples that involve three qubits: ({\em i}) three-particle Greenberger-Horne-Zeilinger entanglement, ({\em ii}) quantum teleportation, and ({\em iii}) a simple quantum error correction network. It is found that the

J. Ahn, D. N. Hutchinson, C. Rangan, P. H. Bucksbaum

A terahertz half-cycle pulse was used to retrieve information stored as quantum phase in an $N$-state Rydberg atom data register. The register was prepared as a wave packet with one state phase-reversed from the others (the &#34;marked bit&#34;). A half-cycle pulse then drove a significant portion of the electron probability into the flipped state via multim

Hyun Kyu Lee, Chul H. Lee, Maurice H. P. M. van Putten

The electric charge on rotating black holes is calculated to be ~ BJ in the force-free configuration of Ghosh (2000), with a horizon flux of ~ BM^2. This charge is gravitationally weak for B ~ 10^{15} G, so that the Kerr metric applies. Being similar to the electric charge of a magnetar, both electric charge and magnetic flux should be, in sign and order of