December 2001 arXiv papers — page 3

Kurt Haller

A gauge-invariant color-charge operator is defined and related to an integral of the gauge-invariant chromoelectric field over a closed surface. We discuss the case of a surface all of whose points are a macroscopic distance from a system of quarks and gluons which it entirely surrounds. When this system of quarks and gluons forms a hadron or an object compo

Tzihong Chiueh

Dynamics of the multi-component, multi-field quintessence and gravity is formulated as relativistic N-particle dynamics, embedded in a static viscus flat space and under the forces given by an interacting Lorentz scalar potential via exchange of field bosons. The Ratra-Peebles power-law potential of effective single-field quintessence can be derived from thi

Han-Ying Guo, Ke Wu

Some problems on variations are raised for classical discrete mechanics and field theory and the difference variational approach with variable step-length is proposed motivated by Lee's approach to discrete mechanics and the difference discrete variational principle for difference discrete mechanics and field theory on regular lattice. Based upon Hamilto

E. Gilboa

We investigate the interactions of color neutral fields with gluons in the regge region, and propose a model in which the field strength of the gluons couple to these fields. This model yields to first order in perturbation theory a structure function which coincides with that obtained in deep inelastic scattering (in the Double Log Approximation of QCD) to

Nikita O. Agasian

We study thermodynamic properties of the QCD vacuum in a magnetic field below chiral phase transition. The hadronic phase free energy in a constant homogeneous magnetic field is calculated in the framework of the chiral perturbation theory at non-zero pionic mass. It is demonstrated that the order parameter of the chiral phase transition remains constant pro

Colin D. Froggatt

We first discuss an approach to the fermion mass problem, according to which the whole of flavour mixing for quarks is determined by the mechanism responsible for generating the physical masses of the up and down quarks: the Lightest Flavour Mass Generation model. Then we consider fermion masses in the Anti-grand Unification Theory and, in particular, the ne

L. B. Okun

Max Planck introduced four natural units: h, c, G, k. Only the first three of them retained their status, representing the so called cube of theories, after the theory of relativity and quantum mechanics were created and became the pillars of physics. This short note is a little pebble on the tombstone of Michael Samuilovich Marinov.

M. Aoki, K. Hagiwara, Y. Hayato, T. Kobayashi

We study physics potential of Very Long Base-Line (VLBL) Neutrino-Oscillation Experiments with the High Intensity Proton Accelerator (HIPA), which will be completed by the year 2007 in Tokai-village, Japan, as a joint project of KEK and JAERI (Japan Atomic Energy Research Institute). The HIPA 50 GeV proton beam will deliver neutrino beams of a few GeV range

Shmuel Nussinov, Robert Shrock

We analyze $n - \bar n$ oscillations in generic models with large extra dimensions in which standard-model fields propagate and fermion wavefunctions have strong localization. We find that in these models $n - \bar n$ oscillations might occur at levels not too far below the current limit.

Takeo Moroi, Tomo Takahashi

We discuss effects of cosmological moduli fields on the cosmic microwave background (CMB). If a modulus field ϕonce dominates the universe, the CMB we observe today is from the decay of ϕand its anisotropy is affected by the primordial fluctuation in the amplitude of the modulus field. As a result, constraints on the inflaton potential from the CMB anisotrop

Steen Hannestad

Recent progress in neutrino physics has been rapid, to a large extent thanks to observations of neutrinos produced in astrophysical environments. Here, we review the current standing on such questions as neutrino masses and mixings, focusing mainly on the interplay between neutrino physics, astrophysics and cosmology.

Roland E. Allen, Antonio R. Mondragon

In a GUT scenario with unconventional supersymmetry, Higgs bosons can be sneutrinos.

P. K. Kabir, X. Song

It is generally assumed that deviations from flavor SU(3) symmetry arise entirely from quark mass-differences, reflected in the mass splittings between strange and nonstrange members of the same SU(3) multiplet. Under this assumption, a parametrization is proposed which expresses the ratios of Gamow-Teller to Fermi matrix elements for nucleon and hyperon bet

I. B. Khriplovich, R. V. Korkin

The maximum entropy of a quantized surface is demonstrated to be proportional to the surface area in the classical limit. The result is valid in loop quantum gravity, and in a somewhat more general class of approaches to surface quantization. The maximum entropy is calculated explicitly for some specific cases.

Z. Golda, A. Woszczyna

Density perturbations in the flat (K=0) Robertson-Walker universe with radiation ($p=ε/3$) and positive cosmological constant ($Λ>0$) are investigated. The phenomenon of anomalous dispersion of acoustic waves on $Λ$ is discussed.

Ettore Minguzzi

We deal with the problem of identifying a background structure and its perturbation in tetrad theories of gravity. Starting from a peculiar trivial principal bundle we define a metric which depends only on the gauge connection. We find the allowed four-dimensional structure groups; two of them turn out to be the translation group T_4 and the unitary group U(

Erik Luijten, Henk W. J. Blöte

We investigate phase transitions of two-dimensional Ising models with power-law interactions, using an efficient Monte Carlo algorithm. For slow decay, the transition is of the mean-field type; for fast decay, it belongs to the short-range Ising universality class. We focus on the intermediate range, where the critical exponents depend continuously on the po

A. -K. Jappsen, A. Amann, A. Wacker, E. Schomburg

The complex impedance of a semiconductor superlattice biased into the regime of negative differential conductivity and driven by an additional GHz ac voltage is computed. From a simulation of the nonlinear spatio-temporal dynamics of traveling field domains we obtain strong variations of the amplitude and phase of the impedance with increasing driving freque

G. Litak

We apply the Coherent Potential Approximation (CPA) to a simple extended Hubbard model with a nearest and next nearest neighbour hopping for disordered superconductors with s-, d- and p-wave pairing. We show how the Van Hove singularities in the electron density of states enhance the transition temperature Tc for exotic superconductors in a clean and weakly

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

In this paper, the Curie temperature of ferroelectric films is studied using spin-1/2 transverse Ising model with long-range interaction within the framework of the effective-field theory. The dependence of the Curie temperature on the thickness of the film, the surface interaction and the transverse field were investigated. It is assumed that the long-range

Y. V. Bludov

The paper deals with the theoretical investigation of plasmons in weakly disordered array of quantum wires, consisting of finite number of quantum wires, arranged at an equal distance from each other. The array of quantum wires is characterized by the fact that the density of electrons of one "defect" quantum wire was different from that of other qua

G. Carapella, G. Costabile, R. Latempa, N. Martucciello

We report the observation of the ratchet effect for a relativistic flux quantum trapped in an annular Josephson junction embedded in an inhomogeneous magnetic field. In such a solid state system mechanical quantities are proportional to electrical quantities, so that the ratchet effect represents the realization of a relativistic-flux-quantum-based diode. Me

Z. Wilamowski, W. Jantsch

The longitudinal spin relaxation time, T1, in a Si/SiGe quantum well is determined from the saturation of the ESR signal. We find values of a few microseconds. Investigations of T1 as a function of Fermi energy, concentration of scattering centers and of the momentum scattering time lead to the conclusion that for high electron mobility the spin relaxation i

I. Kakeya, T. Wada, K. Kadowaki, M. Machida

The Josephson plasma resonance has been investigated in Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ single crystals in parallel magnetic fields to the $ab$-plane. We found two resonance modes; one appears at higher frequency in high fields above the plasma frequency $ω_p$ at zero field and absolute zero, and the other lies below $ω_p$ and is observed only in magnetic fiel

David C. Koo

DEEP is a two-phase spectral survey of faint field galaxies with the Keck Telescopes. The goals include exploring galaxy formation and evolution, mapping distant large scale structures, and constraining cosmology. DEEP, since its inception in the early 1990's, has been distinguished by an emphasis on studying the kinematics and masses of distant galaxies

F. Bernardeau, S. Colombi, E. Gaztanaga, R. Scoccimarro

We review the formalism and applications of non-linear perturbation theory (PT) to understanding the large-scale structure of the Universe. We first discuss the dynamics of gravitational instability, from the linear to the non-linear regime. This includes Eulerian and Lagrangian PT, non-linear approximations, and a brief description of numerical simulation t

A. Morales

An overview of the current status of WIMP direct searches is presented, emphasizing strategies, achievements and prospects.

Diego F. Torres, Gustavo E. Romero, Ernesto F. Eiroa

We propose that some of the high-latitude unidentified EGRET gamma-ray sources could be the result of gravitational lensing amplification of the innermost regions of distant, faint, active galactic nuclei. These objects have gamma-ray emitting regions small enough as to be affected by microlensing of stars in interposed galaxies. We compute the gravitational

A. L. Pokrovsky, A. L. Efros

An exact analytical theory of the electromagnetic waves in metallic photonic crystals with a small volume fraction of a metal is presented. It is shown that there are waves with a very low cutoff frequency $ω_0$ and that the permittivity $ε$ is negative below $ω_0$. We show that if the crystal is embedded into a medium with negative $μ$, it has no propagatin

Amir H. Abbassi, Sh. Khosravi, Amir M. Abbassi

We present our derivations for Kerr-deSitter metric in a proper comoving coordinate system.It asymptotically approaches to the deSitter metric in Robertson-walker form.This has been done by considring the stationary axially-symmetric spacetime in which motion of particle is integrable.That is the Hamilton-Jacobi and Klein-Gordon equations are separable.In th

D. Bar, L. P. Horwitz

We have previously studied properties of a one-dimensional potential with $N$ equally spaced identical barriers in a (fixed) finite interval for both finite and infinite $N$. It was observed that scattering and spectral properties depend sensitively on the ratio $c$ of spacing to width of the barriers (even in the limit $N \to \infty$). We compute here the s

R. Apreda, F. Bigazzi, A. L. Cotrone, M. Petrini

We discuss various aspects of gauge theories realized on the world-volume of wrapped branes. In particular we analyze the coupling of SYM operators to space-time fields both in N=1 and N=2 models and give a description of the gluino condensate in the Maldacena-Nunez N=1 solution. We also explore the seven dimensional BPS equations relevant for these solution

JLQCD Collaboration, S. Aoki, R. Burkhalter, M. Fukugita

We present a polynomial hybrid Monte Carlo (PHMC) algorithm for lattice QCD with odd numbers of flavors of O(a)-improved Wilson quark action. The algorithm makes use of the non-Hermitian Chebyshev polynomial to approximate the inverse square root of the fermion matrix required for an odd number of flavors. The systematic error from the polynomial approximati

Sean A. Hartnoll

Exact $SU(2)\times U(1)$ self-gravitating BPS global monopoles in four dimensions are constructed by dimensional reduction of eight dimensional metrics with $G_2$ holonomy asymptotic to cones over $S^3\times S^3$. The solutions carry two topological charges in an interesting way. They are generically axially but not spherically symmetric. This last fact is r

Yu. S. Kalashnikova, A. V. Nefediev

In this letter we discuss the masses and the splittings of 1(2S+1)P_J states in the spectrum of D and B mesons, as they appear in the approach of the QCD string with quarks at the ends. We find good agreement of our predictions with those of other QCD-motivated models as well as with the lattice and experimental data, including recent experimental results. W

Toshihiko Ota, Joe Sato, Nao-aki Yamashita

We discuss the measurement of new physics in long baseline neutrino oscillation experiments. Through the neutrino oscillation, the probability to detect the new physics effects such as flavor violation is enhanced by the interference with the weak interaction. We carefully explain the situations that the interference can take place. Assuming a neutrino facto

Cheng-Ching Wang, Pi-Gang Luan

Dielectric response effects on wave localization in random periodic-on-average layered systems (POAS) are studied. Based on Monte Carlo simulations and products of Random Matrices, statistics of the Lyapunovmexponent are determined efficiently for very long systems. A novel oscillatory behavior for the Lyapunov exponent is found and explained for mildly stro

Li Xiao, G. L. Long, Hai-Yang Yan, Yang Sun

Compared with classical search algorithms, Grover quantum algorithm [ Phys. Rev. Lett., 79, 325(1997)] achieves quadratic speedup and Bruschweiler hybrid quantum algorithm [Phys. Rev. Lett., 85, 4815(2000)] achieves an exponential speedup. In this paper, we report the experimental realization of the Bruschweiler$ algorithm in a 3-qubit NMR ensemble system. T

Ken-ichi Nakao, Kouji Nakamura, Takashi Mishima

The initial data of gravity for a cylindrical matter distribution confined on the brane is studied in the framework of the single brane Randall-Sundrum scenario. In this scenario, 5-dimensional aspect of gravity appears in the short range gravitational interaction. We found that the sufficiently thin configuration of matter leads to the formation of the marg

A. Zh. Muradyan, G. A. Muradyan

The eigenstate problem of the Jaynes-Cummings model on the basis of complete Hamiltonian, including the center-of -mass kinetic energy operator, is treated. The energy spectrum and wave functions in standing-wave (SW)- and counterpropagating waves (CPW)- cases are calculated and compared with each other. It is shown that in CPW-case i) the atomic momentum di

G. S. Agarwal, R. R. Puri, R. P. Singh

We point out the relation between the work of Zheng and ours, APS [G.S. Agarwal, R.R. Puri, and R.P. Singh, Phys. Rev. A 56, 2249 (2001)] and show the important connection between the atomic cat state and the GHZ states.

L. Xiao, G. L. Long

Searching a marked item or several marked items from an unsorted database is a very difficult mathematical problem. Using classical computer, it requires $O(N=2^n)$ steps to find the target. Using a quantum computer, Grover's algorithm uses $O(\sqrt{N=2^n})$ steps. In NMR ensemble computing, Brushweiler's algorithm uses $\log N$ steps. In this Letter

V. I. Man'ko, E. V. Shchukin

Green function and linear integrals of motion for a charged particle moving in electric field are discussed. Wigner function and tomogram of the ststionary states of the charge are obtained. Connection of quantum propagators for Schrodinger evolution equation, Moyal evolution equation and evolution equation in tomographic probability representation for charg

V. I. Man'ko, V. A. Sharapov, E. V. Shchukin

The systems with multimode nonstationary Hamiltonians quadratic in position and momentum operators are reviewed. The tomographic probability distributions (tomograms) for the Fock states and Gaussian states of the quadratic systems are discussed. The tomograms for the Fock states are expressed in terms of multivariable Hermite polynomials. Using the obvious

A. B. Kukushkin, V. A. Rantsev-Kartinov

A brief review is given of the progress in studying the long-lived filaments (LLFs) in fusion plasmas (tokamaks, Z-pinch, plasma focus). The paper reports on (i) resolving the fine structure of LLFs, and (ii) verification of our hypothesis (1998) which suggested the LLFs to possess a microsolid skeleton. The recent proof-of-concept studies showed the presenc

O. S. Ougolnikov, I. A. Maslov

This work is devoted to the study of solar light that experiences single and multiple scattering in the atmosphere at the twilight time. The work is based on polarimetric observations of the twilight sky that were conducted in 1997 and 2000 for different color bands. Basing on the results of observations, the contribution of single-scattered light depending

Tadafumi Ohsaku, Kizashi Yamaguchi

We investigate the method to combine the techniques of quantum chemisty with QED. In our theory, we treat the N-electron system and the Dirac sea on an equal footing; we regard both of them as the dynamical degrees of freedom of a many-body system. After the introduction of our QED-SCF method, the QED-SCF solutions are classified into several classes on the

Tadafumi Ohsaku, Shusuke Yamanaka, Daisuke Yamaki, Kizashi Yamaguchi

For studying the group theoretical classification of the solutions of the density functional theory in relativistic framework, we propose quantum electrodynamical density-matrix functional theory (QED-DMFT). QED-DMFT gives the energy as a functional of a local one-body $4\times4$ matrix $Q(x)\equiv -<ψ(x)\barψ(x)>$, where $ψ$ and $\barψ$ are 4-component Dira

Tadafumi Ohsaku

To obtain the basis for combining various many-body techniques to QED in a consistent manner, we investigate the theory of quantum electrodynamical self-consistent fields. The reserch interest was born mainly of the electronic structure theory, thus we consider of atomic and moleculer systems as our main subjects. But the formalism is more fundamental. First

Y. M. Zhao, A. Arima, N. Yoshinaga

We propose a simple approach to predict the angular momentum I ground state (I g.s.) probabilities of many-body systems that does not require the diagonalization of hamiltonians with random interactions. This method is found to be applicable to {\bf all} cases that have been discussed: even and odd fermion systems (both in single-j and many-j shells), and bo

Vadim Kostrykin

It is well known that the sum of negative (positive) eigenvalues of some finite Hermitian matrix $V$ is concave (convex) with respect to $V$. Using the theory of the spectral shift function we generalize this property to self-adjoint operators on a separable Hilbert space with an arbitrary spectrum. More precisely, we prove that the spectral shift function i

Pavel Etingof

The notion of a geometric crystal was introduced by A.Berenstein and D.Kazhdan, motivated by the needs of representation theory of p-adic groups. It was shown by A.Braverman, A.Berenstein, and D.Kazhdan that some particular geometric crystals give rise to an interesting birational automorphism R of the Cartesian square of an n-dimensional torus, which satisf

Lee Rudolph

[Original abstract (1992):] The modulus of quasipositivity q(K) of a knot K was introduced as a tool in the knot theory of complex plane curves, and can be applied to Legendrian knot theory in symplectic topology. It has also, however, a straightforward characterization in ordinary knot theory: q(K) is the supremum of the integers f such that the framed knot

B. Enriquez, V. Rubtsov

We construct commuting families in fraction fields of symmetric powers of algebras. The classical limit of this construction gives Poisson commuting families associated with linear systems. In the case of a K3 surface S, they correspond to lagrangian fibrations introduced by Beauville. When S is the canonical cone of an algebraic curve C, we construct commut

John F. Donoghue, Barry R. Holstein, Björn Garbrecht, Thomas Konstandin

We use effective field theory techniques to examine the quantum corrections to the gravitational metrics of charged particles, with and without spin. In momentum space the masslessness of the photon implies the presence of nonanalytic pieces $\sim \sqrt{-q^2},q^2\log -q^2$ etc. in the form factors of the energy-momentum tensor. We show how the former reprodu

Valeri V. Dvoeglazov

We extend the previous series of articles [HPA] devoted to finding mappings between the Weinberg-Tucker-Hammer formalism and antisymmetric tensor fields. Now we take into account solutions of different parities of the Weinberg-like equations. Thus, the Proca, Duffin-Kemmer and Bargmann-Wigner formalisms are generalized.

A. E. Dorokhov

Nonperturbative nolocal structure of QCD vacuum is well described by instanton model. Specific helicity and flavor structure of zero modes of quarks in instanton field allows simultaneously to explain some important features of low- and high- energy hadron phenomemology. The basic characteristics of hadron spectrum, partonic sum rules, heavy-quark potential

A. Szczurek, N. N. Nikolaev, J. Speth

We discuss the onset of the dominance of the Glauber-Gribov-Landshoff (GGL) component of pQCD hard two-gluon (2G) exchange contribution to hard elastic $ππ$ scattering at moderate energies . Such a hard $ππ$ scattering could via final state interaction on the $γγ\to π^+ π^-$ reaction in which pQCD quark-exchange contribution is known to be short of strength.

Chise Sakaguchi, Toshihiko Hattori, Seiichi Wakaizumi

We define a difference $D_{\rm CP}$ of the neutrino oscillation probability differences with matter effect for the CP-conjugate channels, divided by neutrino beam energy, taken between the two baselines $L = L_1$ and $L =L_2$ with $L_1/E_1 = L_2/E_2$, where $E_1$ and $E_2$ are the neutrino energy for the experiment with $L_1$ and $L_2$, respectively. The qua

Andreas Doering, Hans F. de Groote

In loop quantum gravity in the connection representation, the quantum configuration space $\bar{\mathcal{A}/\mathcal{G}}$, which is a compact space, is much larger than the classical configuration space $\mathcal{A}/% \mathcal{G}$ of connections modulo gauge transformations. One finds that $% \bar{\mathcal{A}/\mathcal{G}}$ is homeomorphic to the space $Hom(%

Manoelito M. de Souza

What is the nature - continuous or discrete - of matter and of its fundamental interactions? The physical meaning, the properties and the consequences of a discrete scalar field are discussed; limits for the validity of a mathematical description of fundamental physics in terms of continuum fields are a natural outcome of discrete fields with discrete intera

Andreas de Vries, Theodor Schmidt-Kaler

The potentials of spin-weighted wave equations in various Kerr-Newman black holes are analyzed. They all form singular potential barriers at the event horizon. Applying the WKB approximation it is shown that no particle can tunnel out of the interior of a static black hole. However, photons inside a non-extremely rotating Kerr black hole may tunnel out into

T. Padmanabhan

The dynamics of our universe is characterised by the density parameters for cosmological constant ($Ω_V$), nonbaryonic darkmatter($Ω_{\rm wimp}$), radiation ($Ω_R$) and baryons ($Ω_B$). To these parameters -- which describe the smooth background universe -- one needs to add at least another dimensionless number ($\sim 10^{-5}$) characterising the strength of

Shin&#39;ichi Nojiri, Sergei D. Odintsov

We investigate the Schwarzschild-Anti-deSitter (SAdS) and SdS BH thermodynamics in 5d higher derivative gravity. The interesting feature of higher derivative gravity is the possibility for negative (or zero) SdS (or SAdS) BH entropy which depends on the parameters of higher derivative terms. The appearence of negative entropy may indicate a new type instabil

Makoto Natsuume

We review the current status of the singularity problem in string theory for non-experts. After the problem is discussed from the point of view of supergravity, we discuss classic examples and recent examples of singularity resolution in string theory.

Qingguo Zheng, Ke Xu, Weifeng Lv, Shilong Ma

Alarm correlation plays an important role in improving the service and reliability in modern telecommunications networks. Most previous research of alarm correlation didn&#39;t consider the effect of noise data in Database. This paper focuses on the method of discovering alarm correlation rules from database containing noise data. We firstly define two param

Alireza Saffarzadeh

Spin-polarized tunneling in FMS/M/FMS double tunnel junctions where FMSs are ferromagnetic semiconductor layers and M is a metal spacer is studied theoretically within the single-site coherent potential approximation (CPA). The exchange interaction between a conduction electron and localized moment of the magnetic ion is treated in the framework of the s-f m

Tetsuo Matsui

We propose a new model of neural network. It consists of spin variables to describe the state of neurons as in the Hopfield model and new gauge variables to describe the state of synapses. The model possesses local gauge symmetry and resembles lattice gauge theory of high-energy physics. Time dependence of synapses describes the process of learning. The mean

C. B. Hanna, J. C. Diaz-Velez, A. H. MacDonald

We argue that broken-symmetry states with either spatially diagonal or spatially off-diagonal order are likely in the quantum Hall regime, for clean multiple quantum well (MQW) systems with small layer separations. We find that for MQW systems, unlike bilayers, charge order tends to be favored over spontaneous interlayer coherence. We estimate the size of th

Luciano R. da Silva, Gerald Paul, Shlomo Havlin, Don R. Baker

We consider the cluster and backbone mass distributions between two lines of arbitrary orientations and lengths in porous media in three dimensions, and model the porous media by bond percolation at the percolation threshold $p_c$. We observe that for many geometrical configurations the mass probability distribution presents power law behavior. We determine

K. Ivanova, H. N. Shirer, E. E. Clothiaux, N. Kitova

The complex structure of a typical stratus cloud base height (or profile) time series is analyzed with respect to the variability of its fluctuations and their correlations at all experimentally observed temporal scales. Due to the underlying processes that create these time series, they are expected to have multiscaling properties. For obtaining reliable me

A. S. Alexandrov

The &#39;proof&#39; of the possibility of the slab or stripe phase separation in polar semiconductors, proposed recently by E. L. Nagaev (Phys. Rev. B64 (2001) 014401) is shown to be erroneous. The fundamental error originates in the double-counting of the electron-phonon interaction with optical phonons.

Tadafumi Ohsaku

We investigate the BCS and generalized BCS theories in the relativistic quantum field theory. We select the gauge freedom as U(1), and introduce a BCS-type effective attractive interaction. After introducing the Gor&#39;kov formalism and performing the group theoretical consideration of the mean fields, we solve the relativistic Gor&#39;kov equation and obta

Dae Kwan Kim, Patrick Roblin, Kwang-Sup Soh, Chul Koo Kim

The transport in double-barrier heterostructures of electrons interacting with longitudinal optical phonons in the presence of parallel electric and magnetic fields is analyzed theoretically with the aid of a 3-dimensional quantum transport simulator. Inter Landau state transitions induced by LO-phonon scattering-assisted resonant-tunneling is shown to be an

Pieter G. van Dokkum

Elliptical and S0 galaxies dominate the galaxy population in nearby rich clusters such as Coma. Studies of the evolution of the colors, M/L ratios, and line indices of early-type galaxies indicate that they have been a highly homogeneous, slowly evolving population over the last ~65% of the age of the Universe. On the other hand, recent evidence suggests tha

Martin Harwit, Edwin A. Bergin

We report the first detection of thermal water vapor emission in the 557 GHz, $1_{10} - 1_{01}$ ground state transition of ortho-H$_2$O toward VY Canis Majoris. In observations obtained with the Submillimeter Wave Astronomy Satellite (SWAS), we measured a flux of $\sim 450 $Jy, in a spectrally resolved line centered on a velocity $v_{LSR} = 25 $km s$^{-1}$ w

Vivek K. Agrawal, Sudip Bhattacharyya

We present a detailed and systematic investigation of correlated spectral and timing properties of the Z source GX 349+2, using a huge amount (about 40 ks) of good quality data from September 29, 1998 to October 13, 1998, obtained with the Proportional-Counter-Array on-board RXTE satellite. We, for the first time, give a detailed comparison between the norma

V. E. Zavlin, G. G. Pavlov, D. Sanwal, R. N. Manchester

We report on spectral and timing observations of the nearest millisecond pulsar J0437-4715 with Chandra. The pulsar spectrum, detected up to 7 keV, cannot be described by a simple one-component model. We suggest that it consists of two components, a nonthermal power-law spectrum generated in the pulsar magnetosphere, with a photon index about 2, and a therma

Milan M. Cirkovic, Marina Radujkov

An estimate of the maximal informational content available to advanced extraterrestrial or future (post)human civilizations is presented. It is shown that the fundamental thermodynamical considerations may lead to a quantitative estimate of the largest quantity of information to be processed by conceivable computing devices. This issue is interesting from th

A. Retter, Y. Chou, T. Bedding

The detection of two similar periodicities (3001 and 3028 s) in the light curve of V1405 Aql, a low mass X-ray Binary (LMXRB), has attracted the attention of many observers. Two basic competing models have been offered for this system. According to the first, V1405 Aql is a triple system. The second model invokes the presence of an accretion disc that preces

Ayumu Sugita

We consider generalized Husimi distributions for many-body systems, and show that their moments are good measures of complexity of many-body quantum states. Our construction of the Husimi distribution is based on the coherent state of the single-particle transformation group. Then the coherent states are independent-particle states, and, at the same time, th

Marcos Marino, Ricardo Schiappa

We extend some aspects of vacuum string field theory to superstring field theory in Berkovits&#39; formulation, and we study the star algebra in the fermionic matter sector. After clarifying the structure of the interaction vertex in the operator formalism of Gross and Jevicki, we provide an algebraic construction of the supersliver state in terms of infinit

Roy Joshua

In this paper we define an explicit E_{infinity}-structure, i.e. a coherently homotopy associative and commutative product on chain complexes defining (integral and mod-l) motivic cohomology as well as mod -l étale cohomology. We also discuss several applications. In addition, our constructions show that the source of the E_{\infinity}-structure on the motiv

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

Long-range effects on the pyroelectric coefficient and susceptibility of a ferroelectric bilayer with a ferroelectric interfacial coupling are investigated by use of the transverse Ising model within the framework of mean-field theory. The effects of the interfacial coupling and the transverse field on the pyroelectric coefficient and susceptibility of the b

Yu. G. Naidyuk, I. K. Yanson, L. V. Tyutrina, N. L. Bobrov

We have analyzed about 100 voltage-dependent differential resistance dV/dI(V) curves of metallic point contacts between c-axis oriented MgB$_2$ thin film and Ag, which exhibit clear Andreev reflection features connected with the superconducting gap. About one half of the curves show the presence of a second larger gap. The histogram of the double-gap distrib

Kazuo Fujikawa, Masato Ishibashi

It is shown that the conflict between lattice chiral symmetry and the Majorana condition in the presence of Yukawa couplings, which was noted in our previous paper, is related in an essential way to the basic properties of Ginsparg-Wilson operators, namely, locality and species doubling.

Zeqian Chen

In this paper, a quantum model for the binomial market in finance is proposed. We show that its risk-neutral world exhibits an intriguing structure as a disk in the unit ball of ${\bf R}^3,$ whose radius is a function of the risk-free interest rate with two thresholds which prevent arbitrage opportunities from this quantum market. Furthermore, from the quant

V. M. Bystritsky, A. I. Fix, I. V. Glavanakov, P. Grabmayr

The differential cross section for the $^{12}$C$(γ,π^{+}p)$ reaction has been measured in the $Δ$(1232) resonance region at high recoil momenta of the residual nuclear system. The data are analyzed under the assumption that the formation of the $π^+p$ pairs may be interpreted as a $γΔ^{++}\toπ^+p$ process which takes place on a $Δ^{++}$ preexisting in the ta

K. Shizuya

The electromagnetic characteristics of double-layer quantum Hall systems are studied, with projection to the lowest Landau level taken into account and intra-Landau-level collective excitations treated in the single-mode approximation. It is pointed out that dipole-active excitations, both elementary and collective, govern the long-wavelength features of qua

Mark P. Davidson

A model for the motion of a charged particle in the vacuum is presented which, although purely classical in concept, yields Schrodinger&#39;s equation as a solution. It suggests that the origins of the peculiar and nonclassical features of quantum mechanics are actually inherent in a statistical description of the radiative reactive force.

Sameen Ahmed Khan

A summary of results on synchrotron radiation is presented along with notes on its properties and applications. Quantum aspects are briefly mentioned. Synchrotron radiation facilities are described briefly with a detailed coverage to the accelerator programmes in India. The relocated and other upcoming synchrotrons are also described in some detail.

Sameen Ahmed Khan

A general procedure for construction of the formalism of quantum beam optics for any particle is reviewed. The quantum formalism of spin-1/2 particle beam optics is presented starting {\em ab initio} with the Dirac equation. As an example of application the case of normal magnetic quadrupole lens is discussed. In the classical limit the quantum formalism lea

M. Alqadi, W. R. Gibbs

The doubly differential cross sections for the $^4$He$(π^+,π^-) 4p$ reaction were calculated using both a two-nucleon sequential single charge exchange model and an intranuclear cascade code. Final state interactions between the two final protons which were the initial neutrons were included in both methods. At incident pion energies of 240 and 270 MeV the l

Fumitaka Yura, Tetsuji Tokihiro

We propose a box and ball system with a periodic boundary condition (pBBS). The time evolution rule of the pBBS is represented as a Boolean recurrence formula, an inverse ultradiscretization of which is shown to be equivalent with the algorithm of the calculus for the 2Nth root. The relations to the pBBS of the combinatorial R matrix of ${U&#39;}_q(A_N^{(1)}

George Androulakis, Per Enflo

We prove that if T is a strictly singular 1-1 operator defined on an infinite dimensional Banach space X, then for every infinite dimensional subspace Y of X there exists an infinite dimensional subspace Z of Y such that Z contains orbits of T of every finite length and the restriction of T on Z is a compact operator.

George Androulakis, Thomas Schlumprecht

We first include a result of the second author showing that the Banach space S is complementably minimal. We then show that every block sequence of the unit vector basis of S has a subsequence which spans a space isomorphic to its square. By the Pełczyński decomposition method it follows that every basic sequence in S which spans a space complemented in S ha

Dave Witte

This is an expository paper. It is not difficult to see that every group homomorphism from the additive group Z of integers to the additive group R of real numbers extends to a homomorphism from R to R. We discuss other examples of discrete subgroups D of connected Lie groups G, such that the homomorphisms defined on D can (&#34;virtually&#34;) be extended t

M. Deza, I. Rosenberg

We introduce polyhedral cones associated with $m$-hemimetrics on $n$ points, and, in particular, with $m$-hemimetrics coming from partitions of an $n$-set into $m+1$ blocks. We compute generators and facets of the cones for small values of $m,n$ and study their skeleton graphs.

V. D. Gershun

The closed string model in the background gravity field and the antisymmetric B-field is considered as the bihamiltonian system in assumption,that string model is the integrable model for particular kind of the background fields. It is shown, that bihamiltonity is origin of two types of the T-duality of the closed string models. The dual nonlocal Poisson bra

R. Manvelyan, R. Mkrtchyan

Free field equations, with various spins, for space-time algebras with second-rank tensor (instead of usual vector) momentum are constructed. Similar algebras are appearing in superstring/M theories. The most attention is payed to the gauge invariance properties, particularly the spin two equations with gauge invariance are constructed for dimensions 2+2 and