December 1999 arXiv papers — page 21

Igor Rivin

We start by studying the distribution of (cyclically reduced) elements of the free groups with respect to their abelianization. We derive an explicit generating function, and a limiting distribution, by means of certain results (of independent interest) on Chebyshev polynomials; we also prove that the reductions $\mod p$ ($p$ -- an arbitrary prime) of these

W. A. Zuniga-Galindo

In this paper, we prove the rationality of Igusa's local zeta functions of semiquasihomogeneous polynomials with coefficients in a non-archimedean local field K. The proof of this result is based on Igusa's stationary phase formula and some ideas on Neron p-desingularization.

Weiqiang Wang

Given a finite group G and a G-space X, we show that a direct sum $F_G (X) = \bigoplus_{n \geq 0}K_{G_n} (X^n) \bigotimes \C$ admits a natural graded Hopf algebra and $λ$-ring structure, where $G_n$ denotes the wreath product $G \sim S_n$. $F_G (X)$ is shown to be isomorphic to a certain supersymmetric product in terms of $K_G(X)\bigotimes \C$ as a graded al

Christian Lomp

The splitting of the Goldie (or singular) torsion theory has been extensively studied. Here we determine an appropriate dual Goldie torsion theory, discuss its splitting and answer in the negative a question proposed by Ozcan and Harmanci as to whether the splitting of the dual Goldie torsion theory implies the ring to be quasi-Frobenius.

Wolfgang Mück

We introduce the spinor parallel propagator for maximally symmetric spaces in any dimension. Then, the Dirac spinor Green's functions in the maximally symmetric spaces R^n, S^n and H^n are calculated in terms of intrinsic geometric objects. The results are covariant and coordinate-independent.

Cl. Gabriel, Ph Spindel

We compute the Pauli-Jordan, Hadamard and Feynman propagators for the massive metrical perturbations on de Sitter space. They are expressed both in terms of mode sums and in invariant forms.

Renata Kallosh

The supersymmetric flow equations describing the flow of moduli from infinity to the black hole horizon, and vice versa, are derived in the five-dimensional theories where the moduli space of the very special geometry has disjoint branches. The multiple solutions are derived from the `off the horizon' attractor equation. Within each branch, the black hol

Igor Bandos, Jerzy Lukierski, Dmitri Sorokin

We show that in the supersymmetry framework described by a Poincaré superalgebra with tensorial central charges the role of generalized superconformal symmetry which contains all these central charges is played by $OSp(1|2^{k})$, where k=3 for D=4. Following [1,2] we describe the free supertwistor model for $OSp(1|8)$. It appears that in such a scheme the te

G. Ecker, G. Mueller, H. Neufeld, A. Pich

We discuss $π^0$ -$η$ mixing and its implication for $ε'/ ε$ to next-to-leading order in the low-energy expansion. The big effect due to $η$-$η'$ mixing is shown to be largely cancelled by other contributions occurring at the same order in the chiral expansion.

S. Heinemeyer, W. Hollik, G. Weiglein

We analyze the impact of the recent Feynman-diagrammatic (FD) two-loop results for the mass of the lightest CP-even Higgs boson in the MSSM on the theoretical upper bound for mh as a function of tan(beta). The results are compared with previous results obtained by renormalization group (RG) methods. The incorporation of dominant FD two-loop corrections into

J. Kuehn, T. Hahn, R. Harlander

Top quark production in electron-positron annihilation is one of the benchmark reactions at a future linear collider. Both electroweak and QCD corrections are large, amounting to 10% or even more in specific kinematic regions. In this note we present a method which allows to combine the dominant terms from both sources, thus improving considerably the result

A. Denner, S. Dittmaier, M. Roth, D. Wackeroth

First numerical results of the Monte Carlo generator RACOONWW for e+e- --> WW --> 4fermions(+gamma) in the electroweak Standard Model are presented. This event generator is the first one that includes O(alpha) electroweak radiative corrections in the double-pole approximation completely. We briefly describe the strategy of the calculation and give numerical

Mark I. Gorenstein

Strangeness, charmonium and open charm yields in relativistic nucleus-nucleus collisions are considered within statistical model approach as potential signals of the quark-gluon plasma.

Dmitry Ostrovsky

Next-to-leading order correction to the one-particle inclusive cross section in the framework of high energy factorization is calculated. Numerical results for midrapidity region are compared with predictions of conventional calculations based on collinear factorization.

Seungho Choe

We propose a new QCD sum rule analysis for the Lambda(1405) and the Sigma(1620). Using the I=0 and I=1 multiquark sum rules we predict their masses.

B. Alles, M. D'Elia, A. Di Giacomo

We study the topological properties of full QCD with four flavours of dynamical staggered fermions. In particular the topological susceptibility is measured and the problem of the determination of its first derivative is discussed.

D0 Collaboration, B. Abbott

We report a new measurement of the cross section for the production of isolated photons, with transverse energies (ET) above 10 GeV and pseudorapidities |eta| < 2.5, in p pbar collisions at sqrt{s} = 1.8 TeV. The results are based on a data sample of 107.6 pb-1 recorded during 1992--1995 with the D0 detector at the Fermilab Tevatron collider. The background,

D. Hutchcroft

The lightest srpersymmetric particle (LSP) is expected to be stable, massive and neutral. Direct searches for supersymmetric particles in the context of the minimal supersymmetric extension to the standard model have been performed with the ALEPH detector. Using about 175pb-1 of data with centre-of-mass energies near 189GeV a limit on the mass of the LSP of

Y. A. Kulchitsky, M. V. Kuzmin, V. B. Vinogradov

The new simple method of the energy reconstruction for a combined calorimeter, which we called the e/h method, is suggested. It uses only the known e/h ratios and the electron calibration constants and does not require the determination of any parameters by a minimization technique. The method has been tested on the basis of the 1996 test beam data of the co

Roustam Zalaletdinov

The problem of finding an appropriate geometrical/physical index for measuring a degree of inhomogeneity for a given space-time manifold is posed. Interrelations with the problem of understanding the gravitational/informational entropy are pointed out. An approach based on the notion of approximate symmetry is proposed. A number of related results on definit

S. Sahrakorpi, B. Barbiellini, R. S. Markiewicz, S. Kaprzyk

We present all electron computations of the 3D Fermi surfaces (FS&#39;s) in Ba$_{1-x}$K$_{x}$BiO$_{3}$ for a number of different compositions based on the selfconsistent Korringa-Kohn-Rostoker coherent-potential-approximation (KKR-CPA) approach for incorporating the effects of Ba/K substitution. By assuming a simple cubic structure throughout the composition

Guolin Yang, Kazumi Maki

We study theoretically the effect of impurity scattering in f-wave (or E_{2u}) superconductors. The quasi-particle density of states of f-wave superconductor is very similar to the one for d-wave superconductor as in hole-doped high T_c cuprates. Also in spite of anisotropy in Delta(k), both the normalized superfluid density and the thermal conductivity is c

W. Wernsdorfer, R. Sessoli, A. Caneschi, D. Gatteschi

We present details about an experimental method based on the Landau Zener model which allows to measure very small tunnel splittings $Δ$ in molecular clusters Fe8. The measurements are performed with an array of micro-SQUIDs. The observed oscillations of Delta as a function of the magnetic field applied along the hard anisotropy axis are explained in terms o

O. Mazonka, C. Jarzynski

We describe an exactly solvable model which illustrates the Fluctuation Theorem and other predictions for systems evolving far from equilibrium. Our model describes a particle dragged by a spring through a thermal environment. The rate at which the spring is pulled is arbitrary.

J. R. Sanchez

Extensive numerical simulation are reported for the structure and dynamics of large clusters on metal(100) surfaces. Different types of perimeter hopping processes makes center-of-mass of the cluster to follow a a random walk trajectory. Then, a {\it diffusion coefficient} $D$ can be defined as $\lim\limits_{t\to \infty} D(t)$, with $D(t)=< d^2 >/(4t)$ and $

A. C. Maggs

This letter considers the dynamics of a stiff filament, in particular the coupling of twist and bend via writhe. The time dependence of the writhe of a filament is $W_r^2\sim L t^{1/4}$ for a linear filament and $W_r^2\sim t^{1/2} / L $ for a curved filament. Simulations are used to study the relative importance of crankshaft motion and tube like motion in t

J. J. Rodriguez-Nunez, I. Tifrea, S. G. Magalhaes

Re-studying the non-fermi liquid one-particle Green function (NFLGF) we have extended the work of A. Balatsky (Phil. Mag. Lett. 68, 251 (1993)) and L. Yin and S. Chakravarty (Int. J. Mod. Phys. B 10, 805 (1996)), among others. We used the moment approach of W. Nolting (Z. Phys. 255, 25 (1972)) to compute the unknown parameters of the NFLGF&#39;s in the frame

I. M. Suslov

Asymptotically exact results are obtained for the average Green function and density of states of a disordered system for a renormalizable class of models (as opposed to the lattice models examined previously [Zh. Eksp. Teor. Fiz. 106 (1994) 560-584]). For N\sim 1 (where N is an order of the perturbation theory), only the parquet terms corresponding to the h

M. Guerrero, G. Ortiz, J. E. Gubernatis

We report the results of zero temperature quantum Monte Carlo simulations and zero temperature mean-field calculations of the attractive Hubbard model on chains, ladders, and square lattices. We investigated the predictability of the BCS approximation, the dimensional cross-over of the pairing correlation function from one to two dimensions as a function of

Didier Mayou

A phenomenological diffusion law $L(t)\propto t^β$, where L(t) measures the spreading of a wave-packet in a time t, is assumed for perfect quasicrystals. We show that it affects their conductivity with striking differences compared to the case of periodic metals. In the absence of defects the dissipative part of conductivity is non zero even at low frequenci

J. R. Sanchez, C. M. Arizmendi

Fractal time series has been shown to be self-affine and are characterized by a roughness exponent H. The exponent H is a measure of the persistence of the fluctuations associated with the time series. We use a recently introduced method for measuring the roughness exponent, the mobile averages analysis, to compare electrical power demand of two different pl

D. E. Feldman

We study the effect of random porous matrices on the ordering in nematic liquid crystals. The randomness destroys orientational lang-range order and drives the liquid crystal into a glass state. We predict two glass phases one of which possesses quasi-long-range order. In this state the correlation length is infinite and the correlation function of the order

A. Brinkman, A. A. Golubov

The general solution for ballistic electronic transport through double-barrier Josephson junctions is derived. We show the existence of a regime of phase-coherent transport in which the supercurrent is proportional to the single barrier transparency and the way in which this coherence is destroyed for increasing interlayer thickness. The quasiparticle dc cur

A. N. Morozov, A. V. Zvelindovsky, J. G. E. M. Fraaije

We generalize the earlier theory by Fredrickson [J. Rheol. v.38, 1045 (1994)] to study the orientational behaviour of the hexagonal phase of diblock copolymer melt subjected to steady shear flow. We use symmetry arguments to show that the orientational ordering in the hexagonal phase is a much weaker effect than in the lamellae. We predict the parallel orien

W. Wernsdorfer, D. Mailly, A. Benoit

Various single particle measuring techniques are briefly reviewed and the basic concepts of a new micro-SQUID technique are discussed. It allows measurements of the magnetization reversal of single nanometer-sized particles at low temperature. The influence of the measuring technique on the system of interest is discussed.

W. Wernsdorfer, T. Ohm, C. Sangregorio, R. Sessoli

Below 360 mK, Fe8 magnetic molecular clusters are in the pure quantum relaxation regime. We showed recently that the predicted ``square-root time&#39;&#39; relaxation is obeyed, allowing us to develop a new method for watching the evolution of the distribution of molecular spin states in the sample. We measured the distribution P(H) of molecules which are in

W. Wernsdorfer, I. Chiorescu, R. Sessoli, D. Gatteschi

The Landau Zener model has recently been used to measure very small tunnel splittings in molecular clusters of Fe8, which at low temperature behaves like a nanomagnet with a spin ground state of S = 10. The observed oscillations of the tunnel splittings as a function of the magnetic field applied along the hard anisotropy axis are due to topological quantum

W. Wernsdorfer, E. Bonet Orozco, B. Barbara, A. Benoit

Recent progress in experiment on quantum tunnelling of the magnetic moment in mesoscopic systems will be reviewed. The emphasis will be made on measurements of individual nanoparticles. These nanomagnets allow one to test the border between classical and quantum behaviour. Using the micro-SQUID magnetometer, waiting time, switching field and telegraph noise

D. Controzzi

The breakdown of the Kondo effect may be the origin of the anomalous properties of the heavy-fermion compounds at low temperatures. We study the dynamics of one impurity embedded in an antiferromagnetic host at the quantum critical point and show that the impurity is not screened and develops a power law correlation function. This suggests that the breakdown

D. Bolle&#39;, D. Dominguez Carreta

A self-control mechanism for the dynamics of a three-state fully-connected neural network is studied through the introduction of a time-dependent threshold. The self-adapting threshold is a function of both the neural and the pattern activity in the network. The time evolution of the order parameters is obtained on the basis of a recently developed dynamical

Nobukatsu Yoshida, Yukio Tanaka, Junichiro Inoue, Satoshi Kashiwaya

A theory of tunneling conductance in ferromagnetic metal/insulator/triplet - supercondcutor junctions is presented for unitary and non-unitary spin triplet pairing states which are promising candidates for the superconducting paring symmetry of Sr2RuO4. As the magnitude of the exchange interaction in the ferromagnetic metal is increased, the conductance for

Matthias Vojta

The motion of a single hole in a t-J model for the two-dimensional spin-gap compound SrCu_2(BO_3)_2 is investigated. The undoped Heisenberg model for this system has an exact dimer eigenstate and shows a phase transition between a dimerized and a Neel phase at a certain ratio of the magnetic couplings. We calculate the photoemission spectrum in the disordere

E. Barreto, P. So, B. J. Gluckman, S. J. Schiff

We consider the evolution of the unstable periodic orbit structure of coupled chaotic systems. This involves the creation of a complicated set outside of the synchronization manifold (the emergent set). We quantitatively identify a critical transition point in its development (the decoherence transition). For asymmetric systems we also describe a migration o

V. V. Sokolov, O. V. Zhirov, D. Alonso, G. Casati

We study analytically as well as numerically the dynamics of a quantum map near a quantum resonance of an order q. The map is embedded into a continuous unitary transformation generated by a time-independent quasi-Hamiltonian. Such a Hamiltonian generates at the very point of the resonance a local gauge transformation described the unitary unimodular group S

Cesar Briceno, A. Katherina Vivas, Nuria Calvet, Lee Hartmann

Using the 8k x 8k CCD Mosaic Camera on the 1m Schmidt telescope in Venezuela, we are conducting a large-scale, deep optical, multiepoch, photometric (BVRIHa) survey over 120 sq.deg. in the Orion OB association, aimed at identifying the low mass stellar populations with ages less than about 10 Myr. We present initial results for a 34 sq.deg. area spanning Ori

J. Richard Bond, Dmitry Pogosyan, Tarun Souradeep

We calculate the CMB anisotropy in compact hyperbolic universe models using the regularized method of images described in paper-I, including the &#39;line-of-sight `integrated Sachs-Wolfe&#39; effect, as well as the last-scattering surface terms. We calculate the Bayesian probabilities for a selection of models by confronting our theoretical pixel-pixel temp

Arno P. Schoenmakers, A. G. de Bruyn, H. J. A. Rottgering, H. van der Laan

We present a study of the peculiar radio galaxy B 1834+620. It is characterised by the presence of a 420-kpc large edge-brightened radio source which is situated within, and well aligned with, a larger (1.66 Mpc) radio source. Both sources apparently originate in the same host galaxy, which has a R_s-magnitude of 19.7 and a redshift of 0.5194, as determined

Christian R. Kaiser, A. P. Schoenmakers, H. J. A. Rottgering

A Double-Double Radio Galaxy (DDRG) is defined as consisting of a pair of double radio sources with a common centre. In this paper we present an analytical model in which the peculiar radio structure of DDRGs is caused by an interruption of the jet flow in the central AGN. The new jets emerging from the restarted AGN give rise to an inner source structure wi

Arno P. Schoenmakers, A. G. de Bruyn, H. J. A. Rottgering, H. van der Laan

We present four Mpc-sized radio galaxies which consist of a pair of double-lobed radio sources, aligned along the same axis, and with a coinciding radio core. We have called these peculiar radio sources `double-double&#39; radio galaxies (DDRG) and propose a general definition of such sources: A `double-double&#39; radio galaxy consists of a pair of double r

J. Ormes, A. Moiseev, J. Wells

Cosmic ray antiprotons can originate from dark matter annihilating into quarks that subsequently decay into antiprotons. Evaporation of primordial black holes also can produce a significant antiproton flux. Since the spectrum of secondary antiprotons from cosmic ray interactions peaks at ~ 2 GeV and goes down sharply at lower energy, there is a window at ene

A. Moiseev, J. Ormes, H. Arrighi, E. Bloom

The mysterious dark matter has been a subject of special interest to high energy physicists, astrophysicists and cosmologists for many years. According to theoretical models, it can make up a significant fraction of the mass of the Universe. One possible form of galactic dark matter, Weakly Interacting Massive Particles (WIMPs), could be detected by their an

A. Moiseev, J. Norris, J. Ormes, S. Ritz

The Gamma-ray Large Area Space Telescope (GLAST) is now being designed by a number of collaborating institutions. It will study the cosmic gamma radiation from 20 MeV to 300 GeV with high precision and sensitivity, greatly expanding on the important EGRET results. One of the key systems of the instrument, the Anticoincidence Detector (ACD), is designed to re

Pinaki Chatterjee, Lars Hernquist, Ramesh Narayan

We present a model for the anomalous X-ray pulsars (AXPs) in which the emission is powered by accretion from a fossil disk, established from matter falling back onto the neutron star following its birth. The time-dependent accretion drives the neutron star towards a ``tracking&#39;&#39; solution in which the rotation period of the star increases slowly, in t

J. P. Norris, J. T. Bonnell, G. F. Marani, J. D. Scargle

The fast temporal structures and cosmological distances of gamma-ray bursts (GRBs) afford a natural laboratory for testing theories of frequency-dependent propagation of high-energy photons, as predicted for quantum gravity (QG). We calibrate the sensitivity of the proposed Gamma-ray Large Area Space Telescope (GLAST) by performing simulations which include:

K. A. Miller, J. M. Stone

We use three-dimensional magnetohydrodynamical (MHD) simulations to study the formation of a corona above an initially weakly magnetized, isothermal accretion disk. We also describe a modification to time-explicit numerical algorithms for MHD which enables us to evolve highly stratified disks for many orbital times. We find that MHD turbulence driven by the

Jeremy Kepner, Maya Gokhale, Ron Minnich, Aaron Marks

Astronomers are increasingly using Massively Parallel Network of Workstations (MP-NOW) to address their most challenging computing problems. Fully exploiting these systems is made more difficult as more and more modeling and data analysis software is written in interpreted languages (such as IDL, MATLAB, and Mathematica) which do not lend themselves to paral

Jurgen Knodlseder

Gamma-ray line observations provide a versatile tool for studies of nucleosynthesis processes and supernova physics. In particular, the observation of radioactive species in the interstellar medium probes recent nucleosynthesis activity on various time-scales for different kinds of sources. Considerable progress in gamma-ray instrumentation during the last d

Jurgen Knodlseder

Gamma-ray line observations provide a versatile tool for studies of nucleosynthesis processes and supernova physics. In particular, the observation of radioactive species in the interstellar medium probes recent nucleosynthesis activity on various time-scales for different kinds of sources. Considerable progress in gamma-ray instrumentation during the last d

A. Bragaglia, M. Tosi, G. Marconi, E. Carretta

Old open clusters are useful tools to study the Galactic disk properties, both present and past. Populous samples with properties determined both accurately and homogenously are necessary to draw reliable conclusions. We present here our recent work in the field and introduce and discuss results on metallicities.

Rita M. Sambruna

Being dominated by non-thermal (synchrotron and inverse Compton) emission from a relativistic jet, blazars offer important clues to the structure and radiative processes in extragalactic jets. Crucial information is provided by blazars&#39; spectral energy distributions from radio to gamma-rays (GeV and TeV energies), their trends with bolometric luminosity,

HongSheng Zhao

Deriving the 3-dimensional volume density distribution from a 2-dimensional light distribution of a system yields generally non-unique results. The case for nearby dust-free systems is studied, taking into account the extra constraints from the perspective effect. It is shown analytically that a new form of non-uniqueness exists. We can design a Phantom Sphe

A. Franceschini, L. Bassani, L. Cappi, G. L. Granato

We studied with BeppoSAX the infrared luminous galaxy IRAS 09104+4109 over a very wide X-ray band from 0.1 to 80 keV. Our observations indicate the dominance of a thermal component at energies below 8 keV, which we attribute to the free-free emission from the intracluster (IC) plasma surrounding the source. Above 10 keV we find evidence for the existence of

Eugenio Carretta, Raffaele Gratton, Chris Sneden, Angela Bragaglia

We have determined Li, C, N, O, Na, and Fe abundances, and 12C/13C isotopic ratios for a sample of 62 field metal-poor stars (plus 43 taken from the literature). This large sample was used to show that small mass lower-RGB stars (i.e., fainter than the RGB bump) have abundances of light elements in agreement with theoretical predictions from classical evolut

J. Greiner, D. H. Hartmann, W. Voges, Th. Boller

We report on a search for X-ray afterglows from gamma-ray bursts using the ROSAT all-sky survey (RASS) data. If the emission in the soft X-ray band is significantly less beamed than in the gamma-ray band, we expect to detect many afterglows in the RASS. Our search procedure generated 23 afterglow candidates, where about 4 detections are predicted. Follow-up

J. Richard Bond, Dmitry Pogosyan, Tarun Souradeep

CMB anisotropy measurements have brought the issue of global topology of the universe from the realm of theoretical possibility to within the grasp of observations. The global topology of the universe modifies the correlation properties of cosmic fields. In particular, strong correlations are predicted in CMB anisotropy patterns on the largest observable sca

Hsiao-Wen Chen, Kenneth M. Lanzetta, Alberto Fernández-Soto

The Hubble Deep Field images have provided us with a unique chance to relate statistical properties of high-redshift galaxies to statistical properties of \lya absorption systems. Combining an {\em empirical} measure of the galaxy surface density versus redshift with an {\em empirical} measure of the gaseous extent of galaxies, we predict the number density

A. Mahdavi, H. Boehringer, M. J. Geller, M. Ramella

We describe the ROSAT All-Sky Survey-Center for Astrophysics Loose Systems (RASSCALS), the largest X-ray and optical survey of low mass galaxy groups to date. We draw 260 groups from the combined Center for Astrophysics and Southern Sky Redshift Surveys, covering one quarter of the sky to a limiting Zwicky magnitude of 15.5. We detect 61 groups (23%) as exte

Vassiliki Kalogera

The characteristics of black-hole X-ray binaries can be used to obtain information about their evolutionary history and the process of black-hole formation. In this paper I focus on systems with donor masses lower than the inferred black-hole masses. Current models for the evolution of hydrogen-rich, massive stars and of helium stars losing mass in a wind ca

Gary D. Warren

Lorentz time is replaced by three parameters: a global time, a local rate of aging, and a new spatial coordinate. This enables successful reconstruction of relativity&#39;s observables in a four dimensional Euclidean hyperspace. The new formulation predicts that the age of the universe, as inferred from the Hubble Constant, is less than the observed evolutio

Matts Roos, S. M. Harun-or-Rashid

We determine the density parameters $Ω_m$ of gravitating matter and $Ω_Λ$ of vacuum energy, by making a $χ^2$ fit to nine independent astrophysical constraints. Paying rigorous attention to statistical detail, we find that the present best values are $Ω_m=0.31\pm 0.07, Ω_Λ=0.70\pm 0.13$, where these $1σ$ errors are approximately Gaussian (thus trivially conv

Martin Dominik, Kailash C. Sahu

Due to dramatic improvements in the precision of astrometric measurements, the observation of light centroid shifts in observed stars due to intervening massive compact objects (`astrometric microlensing&#39;) will become possible in the near future. Upcoming space missions, such as SIM and GAIA, will provide measurements with an accuracy of 4 to 60 micro-ar

Anita Mehta, G. C. Barker

Two models are presented to study the influence of slow dynamics on granular compaction. It is found in both cases that high values of packing fraction are achieved only by the slow relaxation of cooperative structures. Ongoing work to study the full implications of these results is discussed.

T. Affolder

Top quark production offers the unique opportunity to search for a charged Higgs boson ($H^\pm$), as the contribution from $t\to H^+b\to τ^+νb$ can be large in extensions of the Standard Model. We use results from a search for top quark pair production by the Collider Detector at Fermilab (CDF) in the e$τ+ \ebar_T$+jets and $μτ+\ebar_T$+jets signatures to se

Anton Kapustin

We propose that Little String Theories in six dimensions are quasilocal quantum field theories. Such field theories obey a modification of Wightman axioms which allows Wightman functions (i.e. vacuum expectation values of products of fundamental fields) to grow exponentially in momentum space. Wightman functions of quasilocal fields in x-space violate microl

Carl E. Wolfe, Kim Maltman

Strong isospin-breaking (IB) contributions to both the octet and 27-plet weak K-->2 pi transitions are evaluated at next-to-leading order (NLO) in the chiral expansion. NLO contributions are shown to significantly reduce the leading order result for the potentially large contribution to the $ΔI=3/2$ amplitude resulting from strong isospin-breaking modificati

C. N. Sabbey, A. Oemler, P. Coppi, C. Baltay

We study the large-scale spatial distribution of low-redshift quasars and Seyfert~1 galaxies using a sample of 106 luminous emission-line objects ($\bar{M}_{B} \approx -23$) selected by their H$α$ emission lines in a far-red objective prism survey ($0.2 < z < 0.37$). Of the 106 objects, 25 were previously known AGN (Veron-Cetty and Veron 2000), and follow-up

Apostolos Pilaftsis

We show that the gaugino and higgsino sectors of supersymmetric theories can naturally acquire observable CP violation through radiative effects which originate from large CP-violating trilinear couplings of the Higgs bosons to the third-generation scalar quarks. These CP-violating loop effects are not attainable by evolving the supersymmetric renormalizatio

Jerzy Matyjasek

The approximation of the renormalized stress-energy tensor of the quantized massive scalar, spinor, and vector field in the Reissner- Nordstrom spacetime is constructed. It is achieved by functional differentiation of the lowest order of the Schwinger-DeWitt effective action involving coincidence limit of the Hadamard-Minakshisundaram-DeWitt-Seely coefficien

C. Anastasiou, E. W. N. Glover, C. Oleari

We study the scalar and tensor integrals associated with the pentabox topology: the class of two-loop box integrals with seven propagators - five in one loop and three in the other. We focus on the case where the external legs are light-like and use integration-by-parts identities to express the scalar integral in terms of two master-topology integrals and p

Oded Agam, Igor Aleiner, Anatoly Larkin

This paper is devoted to study of the classical-to-quantum crossover of the shot noise value in chaotic systems. This crossover is determined by the ratio of the particle dwell time in the system, $τ_d$, to the characteristic time for diffraction $t_E \simeq λ^{-1} |\ln \hbar|$, where $λ$ is the Lyapunov exponent. The shot noise vanishes in the limit $t_E \g

L. DiLella

Present results from neutrino experiments at accelerators and nuclear reactors are reviewed with emphasis on neutrino oscillation searches. Future prospects in this field are also discussed.

Moshe Moshe, Norisuke Sakai

D0 brane (D-particle) and D1 brane actions possess first and second class constraints that result in local $κ$ symmetry. The $κ$ symmetry of the D-particle and the D1 brane is extended here into a larger symmetry ($κ_-$ and $κ_+$) in a larger phase space by turning second class constraints into first class. Different gauge fixings of these symmetries result

M. Thorwart, M. Grifoni, P. Hänggi

We investigate on a unified basis tunneling and vibrational relaxation in driven dissipative multistable systems described by their N lowest lying unperturbed levels. By use of the discrete variable representation we derive a set of coupled non-Markovian master equations. We present analytical treatments that describe the dynamics in the regime of strong sys

Martin Kerscher, Istvan Szapudi, Alex Szalay

Nine of the most important estimators known for the two-point correlation function are compared using a predetermined, rigorous criterion. The indicators were extracted from over 500 subsamples of the Virgo Hubble Volume simulation cluster catalog. The ``real&#39;&#39; correlation function was determined from the full survey in a 3000Mpc/h periodic cube. The

Mutsuo Oka

Let $\mathcal N$ be the moduli space of sextics with 3 (3,4)-cusps. The quotient moduli space ${\mathcal N}/G$ is one-dimensional and consists of two components, ${\mathcal N}_{torus}/G$ and ${\mathcal N}_{gen}/G$. By quadratic transformations, they are transformed into one-parameter families $C_s$ and $D_s$ of cubic curves respectively. We study the Mordell

Taejin Lee

We derive the noncommutative Dirac-Born-Infeld action for the $D$-brane, which governs dynamics of $D$-brane with a NS-NS $B$-field in the low energy regime. Depending on some details of the path integral prescriptions, both ordinary Dirac-Born-Infeld action and noncommutative one can be obtained by evaluating the same Polyakov string path integral for the o

Yoji Michishita

We investigate the instanton effects of non-BPS D0-brane in type I string theory. We argue the general properties of these instanton effects and consider these on $R^9\times S^1$ as a simple example using the effective action of D0-brane.

Stephon H. S. Alexander

We investigate a string/M theoretic realization of the varying speed of light scenario. We consider a 3+1 dimensional probe-brane universe in the background of a black hole in the bulk formed by a stack of branes, in the spirit of Kiritsis (hep-th/9906206). We generalize the dynamics of the system at hand by including rotation and Hubble damping of the bulk

M. Adler, P. van Moerbeke

We study the Pfaff lattice, introduced by us in the context of a Lie algebra splitting of gl(infinity) into sp(infinity) and lower-triangular matrices. We establish a set of bilinear identities, which we show to be equivalent to the Pfaff Lattice. In the semi-infinite case, the tau-functions are Pfaffians; interesting examples are the matrix integrals over s

Hui Li, Dimitri Kusnezov

We show that dynamical symmetry methods can be applied to Hamiltonians with periodic potentials. We construct dynamical symmetry Hamiltonians for the Scarf potential and its extensions using representations of su(1,1) and so(2,2). Energy bands and gaps are readily understood in terms of representation theory. We compute the transfer matrices and dispersion r

Hui Li, Dimitri Kusnezov, Francesco Iachello

We study the group theoretical properties of the Lame equation and its relation to su(1,1) and su(2). We compute the band structure, dispersion relation and transfer matrix and discuss the dynamical symmetry limits.

L. V. Bogdanov, B. G. Konopelchenko

Analytic-bilinear approach is used to study continuous and discrete non-isospectral symmetries of the generalized KP hierarchy. It is shown that Möbius symmetry transformation for the singular manifold equation leads to continuous or discrete non-isospectral symmetry of the basic (scalar or multicomponent KP) hierarchy connected with binary Bäcklund transfor

Andrea Aiello

In this work we present a very simple approach to input-output relations in optical cavities, limiting ourselves to one- and two-photon states of the field. After field quantization, we derive the non-unitary transformation between {\em Inside} and {\em Outside} annihilation and creation operators. Then we express the most general two-photon state generated

M. Fleischhauer, S. F. Yelin, M. D. Lukin

We show that it is possible to ``store&#39;&#39; quantum states of single-photon fields by mapping them onto {\it collective} meta-stable states of an optically dense, coherently driven medium inside an optical resonator. An adiabatic technique is suggested which allows to transfer non-classical correlations from traveling-wave single-photon wave-packets int

Giuseppe Castagnoli

In former work, quantum computation has been shown to be a problem solving process essentially affected by both the reversible dynamics leading to the state before measurement, and the logical-mathematical constraints introduced by quantum measurement (in particular, the constraint that there is only one measurement outcome). This dual influence, originated

Andrés Sicard, Mario Vélez

For quantum Turing machines we present three elements: Its components, its time evolution operator and its local transition function. The components are related with the components of deterministic Turing machines, the time evolution operator is related with the evolution of reversible Turing machines and the local transition function is related with the tra

R. S. Ghaskadvi, Sharon Carr, Michael Dennin

It is known that the presence of cations like Ca++ or Pb++ in the water subphase alters the pressure-area isotherms for fatty acid monolayers. The corresponding lattice constant changes have been studied using x-ray diffraction. Reflection-absorption spectroscopy has been used to probe the chemical composition of the film. We report on the first measurements

D. M. Snyder

In quantum mechanics, it is possible to make observations that affect physical entities without there being a physical interaction between the observer and the physical entity measured. Epstein (1945) and Renninger (1960) discussed this situation, and Renninger called this type of observation a &#34;negative observation.&#34; Empirical research on electron s

D. Damanik

We review the recent developments in the spectral theory of discrete one-dimensional Schrödinger operators with potentials generated by substitutions and circle maps. We discuss how occurrences of local repetitive structures allow for estimates of generalized eigenfunctions. Among the recent applications of this general approach are almost sure and uniform r

Pieter Moree, Peter Stevenhagen

Let a and b be non-zero rational numbers that are multiplicatively independent. We study the natural density of the set of primes p for which the subgroup of the multiplicative group of the finite field with p elements generated by (a\mod p) contains (b\mod p). It is shown that, under assumption of the generalized Riemann hypothesis (GRH), this density exist