May 2003 arXiv papers — page 9

Arun K. Pati, Samuel L. Braunstein

It is known that if we can clone an arbitrary state we can send signal faster than light. Here, we show that deletion of unknown quantum state against a copy can lead to superluminal signalling. But erasure of unknown quantum state does not imply faster than light signalling.

M. A. Aguilar, J. M. Isidro, M. Socolovsky

In this note we present a simplified derivation of the fact that the moduli space of flat connections in the abelian Aharonov-Bohm effect is isomorphic to the circle. The length of this circle is the electric charge.

Stefan Weigert

An entirely quantum mechanical approach to diagonalize hermitean matrices has been presented recently. Here, the genuinely quantum mechanical approach is considered in detail for (2x2) matrices. The method is based on the measurement of quantum mechanical observables which provides the computational resource. In brief, quantum mechanics is able to directly a

J. Dukelsky, J. M. Roman, G. Sierra

Comment on the Letter ``Polynomial-Time Simulation of Pairing Models on a Quantum Computer'', L. A. Wu, M. S. Byrd and D. A. Lidar, Phys. Rev. Lett. 89, 057904 (2002).

M. A. Martin-Delgado, M. Navascues

We develop a distillation protocol for multilevel qubits (qudits) using generalized beam splitters like in the proposal of Pan et al. for ordinary qubits. We find an acceleration with respect to the scheme of Bennet et al. when extended to qudits. It is also possible to distill entangled pairs of photons carrying orbital angular momenta (OAM) states that con

Subhash Kak

The standard protocol for teleportation of a quantum state requires an entangled pair of particles and the use of two classical bits of information. Here, we present two protocols for teleportation that require only one classical bit. In the first protocol, chained XOR operations are performed on the particles before one of them is removed to the remote loca

N. Baboi, G. B. Bowden, R. M. Jones, S. G. Tantawi

The wire method is a more rapid and less costly method to measure impedances of RF components compared to methods using a beam. A setup using a single displaced wire to excite and measure transverse resonant modes in accelerating structures for the Next Linear Collider/ Japanese Linear Collider (NLC/JLC) has been built. The RF signal is coupled into and out

E. Tassi, V. S. Titov, G. Hornig

Analytical solutions for reconnective annihilation in curvilinear geometry are presented. These solutions are characterized by current density distributions varying both along the radial and azimuthal coordinates. They represent an extension of previously proposed models, based on purely radially dependent current densities. Possible applications of these so

A. Mary Selvam

The observed long-range spatiotemporal correlations of real world dynamical systems is governed by quantumlike mechanics with inherent non-local connections. In summary, microscopic scale local fluctuations form a unified self-organized adaptive network manifested as the macro-scale dynamical system with implicit ordered energy flow between the larger and sm

Thomas Fuchs, Jambul Gegelia, Stefan Scherer

The electromagnetic form factors of the nucleon are calculated at order $q^4$ in the relativistic formulation of baryon chiral perturbation theory. In order to obtain a consistent power counting for the renormalized diagrams we make use of the extended on-mass-shell renormalization scheme which we have discussed in a recent paper. We analyze the Dirac and Pa

Zi-wei Lin, C. M. Ko

The two-kaon interferometry at RHIC is studied in a multi-phase transport model. Similar to the pion case, we find strong space-time correlation at freeze-out for the kaon emission source, which results in a large positive $R_{\rm out}-t$ term and tends to reduce the $R_{\rm out}/R_{\rm side}$ ratio. Unlike the pion case, the source radii for kaons determine

S. J. Brodsky, L. Frankfurt, R. Gilman, J. R. Hiller

Hard photodisintegration of the deuteron has been extensively studied in order to understand the dynamics of the transition from hadronic to quark-gluon descriptions of the strong interaction. In this work, we discuss the extension of this program to hard photodisintegration of a $pp$ pair in the $^3$He nucleus. Experimental confirmation of new features pred

Yu. E. Titarenko, V. F. Batyaev, V. M. Zhivun, A. B. Koldobsky

Results of experimental cross sections for residual nuclide production in interactions of 200 MeV/A 12C ions and 0.2 and 2.6 GeV protons with nat-Cu, 59Co, and 27Al targets are presented. The residual products are measured at ITEP (Moscow) by gamma-spectrometry with a detector of 1.8 keV resolution in the 1332 keV 60Co gamma-line. The measured data are compa

Yu. E. Titarenko, V. F. Batyaev, E. I. Karpikhin, V. M. Zhivun

Results of measured threshold activation reaction rates in 12C, 19F, 27Al, 59Co, 63Cu, 65Cu, 64Zn, 93Nb, 115In, 169Tm, 181Ta, 197Au, and 209Bi experimental samples placed both along the axis inside and outside a 0.8 GeV proton-irradiated thick W-Na target are presented. Absorption dose rates outside the target are presented as well. The target was irradiated

Yu. E. Titarenko, V. F. Batyaev, V. M. Zhivun, A. B. Koldobsky

Measured at ITEP (Moscow) cross sections for nuclide production in 1.0 GeV proton-irradiated 208Pb and 0.8 GeV proton-irradiated 197Au targets are presented. The cross sections were measured by direct gamma-spectrometry with a high-resolution Ge detector. The measured cross sections are compared with experimental data of GSI (inverse kinematics, 1 GeV/nucleo

Decio Levi, Piergiulio Tempesta, Pavel Winternitz

We discuss umbral calculus as a method of systematically discretizing linear differential equations while preserving their point symmetries as well as generalized symmetries. The method is then applied to the Schrödinger equation in order to obtain a realization of nonrelativistic quantum mechanics in discrete space-time. In this approach a quantum system on

A. von der Heydt, S. Grossmann, D. Lohse

Numerical simulations of fully developed turbulence driven by a modulated energy input rate or driving force are performed within two dynamical cascade models, the GOY shell model and a reduced wave vector set approximation of the Navier-Stokes equation (REWA). The frequency behavior of the system response is studied and compared with predictions from a vari

A. von der Heydt, S. Grossmann, D. Lohse

Isotropic and homogeneous turbulence driven by an energy input modulated in time is studied within a variable range mean-field theory. The response of the system, observed in the second order moment of the large-scale velocity difference D(L,t)=<<(\u(x+L)-\u(x))^2>>~Re(t)^2$, is calculated for varying modulation frequencies w and weak modulation amplitudes.

Yves Gaspar

In this work we establish new forms of Heun-to-Heun transformations and Heun-to-Hypergeometric transformations. The transformations are realised by changing the independent variable in a non-linear way. Using these we also point out some simple examples of transformations between equations that are not Fuchsian and that generalise the Heun-to-Hypergeometric

J. E. Avron, A. Elgart, G. M. Graf, L. Sadun

This paper is about adiabatic transport in quantum pumps. The notion of ``energy shift&#39;&#39;, a self-adjoint operator dual to the Wigner time delay, plays a role in our approach: It determines the current, the dissipation, the noise and the entropy currents in quantum pumps. We discuss the geometric and topological content of adiabatic transport and show

H. Then

We investigate the numerical computation of Maass cusp forms for the modular group corresponding to large eigenvalues. We present Fourier coefficients of two cusp forms whose eigenvalues exceed r=40000. These eigenvalues are the largest that have so far been found in the case of the modular group. They are larger than the 130millionth eigenvalue.

M. Toller

We present a classification, up to isomorphisms, of all the homogeneous spaces of the Lorentz group with dimension lower than six. At the same time, we classify, up to conjugation, all the non-discrete closed subgroup of the Lorentz group and all the subalgebras of the Lorentz Lie algebra. We also study the covariant mappings between some pairs of homogeneou

Tsz Ho Chan

In this paper, we extend the result of Fujii on the second moment of $S(t+h) - S(t)$ to longer range of $h$ under the Riemann Hypothesis and an quantitative form of the Twin Prime Conjecture.

Tsz Ho Chan

In this paper, we study a more general pair correlation function, $F_h(x,T)$, of the zeros of the Riemann zeta function. It provides information on the distribution of larger differences between the zeros.

Tsz Ho Chan

We assume the Riemann Hypothesis and an quantitative form of the Twin Prime Conjecture, and obtain an asymptotic formula for the second moment of $S(T)$ with better error term.

Allan P. Donsig, Alan Hopenwasser

Partial actions of discrete abelian groups can be used to construct both groupoid C*-algebras and partial crossed product algebras. In each case there is a natural notion of an analytic subalgebra. We show that for countable subgroups of the real numbers and free partial actions, these constructions yield the same C*-algebras and the same analytic subalgebra

T. Christiansen

We consider resonances associated to the operator $-\frac{d^2}{dx^2}+V(x)$, where $V(x)=V_+$ if $x>x_M$ and $V(x)=V_-$ if $x<-x_M$, with $V_+\not = V_-$. We obtain asymptotics of the resonance-counting function in several regions. Moreover, we show that in several situations, the resonances, $V_+$, and $V_-$ determine $V$ uniquely up to translation.

Said El Baghdadi, Marco Fontana

In 1994, Matsuda and Okabe introduced the notion of semistar operation, extending the &#34;classical&#34; concept of star operation. In this paper, we introduce and study the notions of semistar linkedness and semistar flatness which are natural generalizations, to the semistar setting, of their corresponding &#34;classical&#34; concepts. As an application,

Matthias Beck, Dennis Pixton

The n&#39;th Birkhoff polytope $B_n$ is the set of all doubly stochastic $n \times n$ matrices, that is, those matrices with nonnegative real coefficients in which every row and column sums to one. A long-standing open problem is the determination of the relative volume of $B_n$. In [arXiv:math.CO/0202267] we introduced a method of calculating this volume an

Athanasios Batakis

We prove that the dimension of the harmonic measure of the complementary of a translation-invariant type of Cantor sets as a continuous function of the parameters determining these sets. This results extend a previous one of the author and do not use ergodic theoretic tools, not applicable to our case.

Hisayosi Matumoto

A holomorphic discrete series can be realized as the space of the holomorphic sections of a homogeneous vector bundle on a bounded symmetric domain. We can embed it into a degenerate principal series realized as the space of hyperfunction sections of a vector bundle on the Shilov boundary by taking the boundary value. We consider an algebraic version of high

Angel Carocca, Rubi E. Rodriguez

The object of this paper is to prove some general results about rational idempotents for a finite group $G$ and deduce from them geometric information about the components that appear in the decomposition of the Jacobian variety of a curve with $G-$action. We give an algorithm to find explicit primitive rational idempotents for any $G$, as well as for ration

Astrid Reifegerste

The number of even 321-avoiding permutations of length n is equal to the number of odd ones if n is even, and exceeds it by the (n-1)/2th Catalan number otherwise. We present an involution that proves a refinement of this sign-balance property respecting the length of the longest increasing subsequence of the permutation. In addition, this yields a combinato

Jarek Kedra

There are two main results. The first states that isotropy subgroups of groups acting transitively on a rationally hyperbolic spaces have infinitely generated rational cohomology algebra. Using this fact, we prove that the analogous statement holds for groups of symplectomorphisms of certain blow-ups.

Jasper V. Stokman

It is shown that a dynamical quantum group arising from a vertex-IRF transformation has a second realization with untwisted dynamical multiplication but nontrivial bigrading. Applied to the $\hbox{SL}(2;\mathbb{C})$ dynamical quantum group, the second realization is naturally described in terms of Koornwinder&#39;s twisted primitive elements. This leads to a

Sever S. Dragomir, Anca C. Gosa

A generalisation of inner product spaces of an inequality due to Ostrowski and applications for sequences and integrals are given.

Alice Chang, Jie Qing, Paul Yang

In this paper we study the topology of conformally compact Einstein 4-manifolds. When the conformal infinity has positive Yamabe invariant and the renormalized volume is also positive we show that the conformally compact Einstein 4-manifold will have at most finite fundamental group. Under the further assumption that the renormalized volume is relatively lar

Stefaan Vaes

An action of a locally compact group or quantum group on a factor is said to be strictly outer when the relative commutant of the factor in the crossed product is trivial. We show that all locally compact quantum groups can act strictly outerly on a free Araki-Woods factor and that all locally compact groups can act strictly outerly on the hyperfinite II_1 f

Haisheng Li

This paper studies certain relations among vertex algebras, vertex Lie algebras and vertex Poisson algebras. In this paper, the notions of vertex Lie algebra (conformal algebra) and vertex Poisson algebra are revisited and certain general construction theorems of vertex Poisson algebras are given. A notion of filtered vertex algebra is formulated in terms of

L. Stodolsky

We consider the behavior of the photon number integral under inversion, concentrating on euclidean space. The discussion may be framed in terms of an additive differential $I$ which arises under inversions. The quantity $\int \int I$ is an interesting integral invariant whose value characterizes different configurations under inversion.

Holger Gies

We analyze the possibility of nonperturbative renormalizability of gauge theories in D > 4 dimensions. We develop a scenario, based on Weinberg&#39;s idea of asymptotic safety, that allows for renormalizability in extra dimensions owing to a non-Gaussian ultraviolet stable fixed point. Our scenario predicts a critical dimension D_cr beyond which the UV fixed

Robert Fleischer

The B-meson system provides many strategies to perform stringent tests of the Standard-Model description of CP violation. In this brief review, we discuss implications of the currently available B-factory data on the angles alpha, beta and gamma of the unitarity triangle, emphasize the importance of Bs studies at hadronic B experiments, and discuss new, theo

Katarzyna Helena Klimek

The results of measurement of beauty quark production at HERA performed by the H1 and ZEUS collaborations are presented. Total cross sections and the differential cross sections have been measured in both the photoproduction and the deep inelastic scattering regimes. The results are compared with the NLO QCD calculations.

Zumin Luo, Jonathan L. Rosner

Using the measured spectrum shape for $B \to π\ell ν$, the rate for $B^+ \to π^+ π^0$, information on the Cabibbo-Kobayashi-Maskawa (CKM) matrix element $|V_{ub}|$, and theoretical inputs from factorization and lattice gauge theory, we obtain an improved estimate of the ``tree&#39;&#39; contribution to $B^0 \to π^+ π^-$. We find the branching ratio $\b(B^0 \

A. Hosaka, D. Jido, M. Oka

Chiral symmetry aspects for baryon properties are studied. After a brief discussion on general framework, we introduce two distinctive chiral group representations for baryons: the naive and mirror assignments. Using linear sigma models, nucleon properties are studied in both representations. Finally, we propose an experiment to distinguish the two assignmen

D. Prorok

The ratio ${dE_{T} \over {dη}} / {dN_{ch} \over {dη}}$ is analyzed in the framework of a single-freeze-out thermal hadron gas model. Decays of hadron resonances are taken into account in evaluations of this ratio. The predictions of the model at the freeze-out parameters, established previously from observed particle yields, agree very well with the ratio me

Michael Begel

We present the first Run II measurements with the DO detector of the inclusive jet and dijet cross sections at sqrt{s}=1.96 TeV. This analysis is based on an integrated luminosity of 34 pb-1. The results from a next-to-leading order perturbative QCD calculation are compared to the measured cross sections. The theoretical calculation agrees with the data.

ALEPH Collaboration, Arno Heister

Searches for stable, hadronizing scalar quarks and gluinos are performed using the data collected with the ALEPH detector at LEP. Gluon splitting into a gluino or a squark pair is searched for at centre-of-mass energies around the Z resonance, in the e+e- -> q qbar gluino gluino and q qbar squark antisquark processes. Stable squark pair production, and stop

D. J. Summers, J. S. Berg, R. B. Palmer, A. A. Garren

A 4600 Hz fast ramping synchrotron is studied as an economical way of accelerating muons from 4 to 20 GeV/c for a neutrino factory. Eddy current losses are minimized by the low machine duty cycle plus thin grain oriented silicon steel laminations and thin copper wires. Combined function magnets with high gradients alternating within single magnets form the l

F. I. Cooperstock, V. Faraoni

In the standard approach to defining a Planck scale where gravity is brought into the quantum domain, the Schwarzschild gravitational radius is set equal to the Compton wavelength. However, ignored thereby are the charge and spin, the fundamental quantized aspects of matter. The gravitational and null-surface radii of the Kerr-Newman metric are used to intro

Alan Barnes, Jose MM Senovilla

Garcia and Campuzano claim to have found a previously overlooked family of stationary and axisymmetric conformally flat spacetimes, contradicting an old theorem of Collinson. In both these papers it is tacitly assumed that the isometry group is orthogonally transitive. Under the same assumption, we point out here that Collinson&#39;s result still holds if on

D. D. Rabounski, L. B. Borissova

This study looks at motion of particles using mathematical methods of chronometric invariants (physical observable values in General Relativity). It is shown that aside for mass-bearing particles and light-like particles &#34;zero-particles&#34; can exist in fully degenerated space-time (zero-space). For a regular observer zero-particles move instantly, thus

E. Minguzzi

Stationary extended frames in general relativity are considered. The requirement of stationarity allows to treat the spacetime as a principal fiber bundle over the one-dimensional group of time translations. Over this bundle a connection form establishes the simultaneity between neighboring events accordingly with the Einstein synchronization convention. The

Markus Jakobsson, Filippo Menczer

We uncover a vulnerability that allows for an attacker to perform an email-based attack on selected victims, using only standard scripts and agents. What differentiates the attack we describe from other, already known forms of distributed denial of service (DDoS) attacks is that an attacker does not need to infiltrate the network in any manner -- as is norma

Keijo Heljanko, Ilkka Niemelä

In this paper bounded model checking of asynchronous concurrent systems is introduced as a promising application area for answer set programming. As the model of asynchronous systems a generalisation of communicating automata, 1-safe Petri nets, are used. It is shown how a 1-safe Petri net and a requirement on the behaviour of the net can be translated into

Andris Ambainis, Markus Jakobsson, Helger Lipmaa

We develop cryptographically secure techniques to guarantee unconditional privacy for respondents to polls. Our constructions are efficient and practical, and are shown not to allow cheating respondents to affect the ``tally&#39;&#39; by more than their own vote -- which will be given the exact same weight as that of other respondents. We demonstrate solutio

Julien Kockelkoren, Herbert Levine, Wouter-Jan Rappel

We introduce a phase field approach for diffusion inside and outside a closed cell with damping and with source terms at the interface. The method is compared to exact solutions (where possible) and the more traditional finite element method. It is shown to be very accurate, easy to implement and computationally inexpensive. We apply our method to a recently

Zhi-Xun Shen

This paper summarizes experimental results presented at the international conference honoring Prof. C.N. Yang&#39;s 80th birthday. I show seven examples that illustrate how one can use angle-resolved photoemission spectroscopy to gain insights into the many-body physics responsible for the rich phase diagram of cuprate superconductors. I hope to give the rea

J. E. Hirsch

When the Fermi level is near the top of a band the carriers (holes) are maximally dressed by electron-ion and electron-electron interactions. The theory of hole superconductivity predicts that only in that case can superconductivity occur, and that it is driven by $undressing$ of the carriers at the Fermi energy upon pairing. Indeed, experiments show that dr

P. Capuzzi, A. Minguzzi, M. P. Tosi

We calculate the spectrum of low-lying collective excitations in a gaseous cloud formed by a Bose-Einstein condensate and a spin-polarized Fermi gas over a range of the boson-fermion coupling strength extending from strongly repulsive to strongly attractive. Increasing boson-fermion repulsions drive the system towards spatial separation of its components (``

M. Radosavljevic, S. Heinze, J. Tersoff, Ph. Avouris

While decreasing the oxide thickness in carbon nanotube field-effect transistors (CNFETs) improves the turn-on behavior, we demonstrate that this also requires scaling the range of the drain voltage. This scaling is needed to avoid an exponential increase in Off-current with drain voltage, due to modulation of the Schottky barriers at both the source and dra

I. V. Stasyuk, A. M. Shvaika

We review two analytical approaches in Dynamical Mean-Field Theory (DMFT) based on a perturbation theory expansion over the electron hopping to and from the self consistent environment. In the first approach the effective single impurity Anderson model (SIAM) is formulated in terms of the auxiliary Fermi-fields and the projection (irreducible Green&#39;s fun

Rolf Schilling

We review phenomenological and microscopic theories of the structural glass transition

S. Ciliberti, T. S. Grigera, V. Martin-Mayor, G. Parisi

A simple model of harmonic vibrations in topologically disordered systems, such as glasses and supercooled liquids, is studied analytically by extending Euclidean Random Matrix Theory to include vector vibrations. Rather generally, it is found that i) the dynamic structure factor shows sound-like Brillouin peaks whose longitudinal/transverse character can on

D. Daghero, R. S. Gonnelli, G. A. Ummarino, O. V. Dolgov

We calculate the tunneling density of states (DOS) of MgB2 for different tunneling directions, by directly solving the real-axis, two-band Eliashberg equations (EE). Then we show that the numeric inversion of the standard single-band EE, if applied to the DOS of the two-band superconductor MgB2, may lead to wrong estimates of the strength of certain phonon b

G. Foffi, F. Sciortino, P. Tartaglia, E. Zaccarelli

The dynamics of star polymers has been investigated via extensive Molecular- and Brownian Dynamics simulations for a large range of functionality $f$ and packing fraction $η$. The calculated isodiffusivity curves display both minima and maxima as a function of $η$ and minima as a function of $f$. Simulation results are compared with theoretical predictions b

R. S. Gonnelli, D. Daghero, G. A. Ummarino, Valeria Dellarocca

The results of the first directional point-contact measurements in MgB2 single crystals, in the presence of magnetic fields up to 9 T either parallel or perpendicular to the ab planes, are presented. By applying suitable magnetic fields, we separated the partial contributions of the sigma and pi bands to the total Andreev-reflection conductance. Their fit wi

F. Chevy, S. Stringari

Using the concept of diffused vorticity and the formalism of rotational hydrodynamics we calculate the eigenmodes of a harmonically trapped Bose-Einstein condensate containing an array of quantized vortices. We predict the occurrence of a new branch of anomalous excitations, analogous to the Kelvin modes of the single vortex dynamics. Special attention is de

Yaron Bromberg, Eli Livne, Baruch Meerson

Granular materials fluidized by a rapidly vibrating bottom plate often develop a fascinating density inversion: a heavier layer of granulate supported by a lower-density region. We employ the Navier-Stokes granular hydrodynamics to follow a density inversion as it develops in time. Assuming a dilute low-Mach-number flow, we derive a reduced time-dependent mo

Keshav N. Shrivastava

In the experiments, the quantity measurd is the product of the charge and the magnetic field from which fractional charge is deduced. There is no objection to measuring the fractional charge as long as it is remembered that the product of the charge and the field has been measured. So If the fraction came from the field rather than from the charge, the exper

V. P. S. Awana, H. Kishan, E. Takayama-Muromachi, T. Watanabe

The Tb-123 phase has been synthesized in single-phase form with the composition TbSr2Cu2.7Mo0.3O7 by solid-state reaction route and its phase purity is confirmed by neutron powder diffraction experiments. As-synthesized sample does not show superconductivity down to 5 K. An unusually high antiferromagnetic ordering temperature (TN) of around 7 K is seen for

E. V. Vakarin, J. P. Badiali

It is shown that there is a mapping of the replica approach to disordered systems with finite replica index $n$ on the Tsallis non-extensive statistics, if the average thermodynamic entropy differs from the information entropy for the probability distribution. In the case of incomplete information the entropic index $q=1-n$ is shown to be related to the degr

Sharan Shetty, Dilip. G. Kanhere, Sourav Pal

We propose a theoretical investigation in this paper to understand the bonding and structural properties of neutral Al4Na4 and anion Al4Na3- clusters. We show that the Al4 species in Al4Na4 and Al4Na3- clusters is a rectangular planar structure with alternate pi-bonds and hence satisfying the basic criteria for anti-aromaticity. We prove that the Al4Na4 and

V. Apaja, E. Krotscheck

We examine the energetics of bulk and layer-roton excitations of 4He in various porous medial such as aerogel, Geltech, or Vycor, in order to find out what conclusions can be drawn from experiments on the energetics about the physisorption mechanism. The energy of the layer-roton minimum depends sensitively on the substrate strength, thus providing a mechani

A. Yu. Aladyshkin, A. S. Mel&#39;nikov, D. A. Ryzhov

Within the phenomenological Ginzburg-Landau theory we investigate the phase diagram of a thin superconducting film with ferromagnetic nanoparticles. We study the oscillatory dependence of the critical temperature on an external magnetic field similar to the Little-Parks effect and formation of multiquantum vortex structures. The structure of a superconductin

Shuo Jin, Kang Xue, Bing-Hao Xie

Yangian $Y(sl(2))$ is realized in the bi-spin system coupled with a time-dependent external magnetic field. It is shown that $Y(sl(2))$ generators can describe the transitions between the ``spin triplet&#39;&#39; and the ``spin singlet&#39;&#39; that evolve with time. Furthermore, new transition operators between the states with Berry phase factor and those

Ryosuke Kadono, Kazuki Ohishi, Akihiro Koda, Wataru Higemoto

The magnetic ground state of an electron-doped cuprate superconductor Pr$_{1-x}$LaCe$_x$CuO$_{4+α-δ}$ ($x=0.11, α\simeq0.04$) has been studied by means of muon spin rotation/relaxation (\msr) over a wide variety of oxygen depletion, $0.03\leδ\le0.12$. Appearance of weak random magnetism over entire crystal volume has been revealed by a slow exponential relax

Masami Takata, Hayaru Shouno, Kazuki Joe, Masato Okada

Solving the error correcting code is an important goal with regard to communication theory.To reveal the error correcting code characteristics, several researchers have applied a statistical-mechanical approach to this problem. In our research, we have treated the error correcting code as a Bayes inference framework. Carrying out the inference in practice, w

Fabrizio Lillo, Rosario N. Mantegna

We study the spectral density of factor models of multivariate time series. By making use of the Random Matrix Theory we analytically quantify the effect of noise dressing on the spectral density due to the finiteness of the sample. We consider a broad range of models ranging from one factor models in time and frequency domain to hierarchical multifactor mod

C. W. J. Beenakker, C. Emary, M. Kindermann, J. L. van Velsen

We demonstrate theoretically that the shot noise produced by a tunnel barrier in a two-channel conductor violates a Bell inequality. The non-locality is shown to originate from entangled electron-hole pairs created by tunneling events -- without requiring electron-electron interactions. The degree of entanglement (concurrence) equals 2(T_1 T_2)^1/2 (T_1+T_2)

Stephan Braig, Shaffique Adam, Piet W. Brouwer

We consider statistical correlations between the heights of conductance peaks corresponding to two different levels in a Coulomb-blockaded quantum dot. Correlations exist for two peaks at the same magnetic field if the field does not fully break time-reversal symmetry as well as for peaks at different values of a magnetic field that fully breaks time-reversa

Igor F. Herbut, Dominic J. Lee

The minimal theory of spin of gapless quasiparticles coupled to fluctuating vortex defects in the phase of the d-wave superconducting order parameter at T=0 is studied. With the proliferation of the vortex loops the theory reduces to the previuosly studied QED3, with its concomitant spin-density-wave (chiral) instability. We find a single superconductor-insu

Martin White

The Lya forest has emerged as one of the few systems capable of probing small-scale structure at high-z with high precision. In this talk I highlight two areas in which the Lya forest is shedding light on fundamental questions in cosmology, one speculative and one which should be possible in the near future.

Joern Rossa, Ralf-Juergen Dettmar

In this second paper on the investigation of extraplanar diffuse ionized gas in nearby edge-on spiral galaxies we present the actual results of the individual galaxies of our H-alpha imaging survey. A grand total of 74 galaxies have been studied, including the 9 galaxies of a recently studied sub-sample (Rossa & Dettmar 2000). 40.5% of all studied galaxies r

Y. G. Tsamis, M. J. Barlow, X. -W. Liu, I. J. Danziger

We present spectrophotometry of 12 Galactic and 3 Magellanic Cloud planetary nebulae (PNe). Nine of the Galactic PNe were observed by scanning the slit across the PN. We use the fluxes of collisionally excited lines (CELs) to derive electron densities (D&#39;s) and temperatures (T&#39;s), and ionic abundances. We find that the D&#39;s derived from optical CE

Scott Dodelson, Glenn D. Starkman

A long-standing problem in astrophysics is to measure the mass associated with galaxies. Gravitational lensing provides one of the cleanest ways to make this measurement. To date, the most powerful lensing probes of galactic mass have been multiply imaged QSO&#39;s (strong lensing of a background point source) and galaxy-galaxy lensing (weak deformation of m

Richard A. Battye, Jochen Weller

Sunyaev Zel&#39;dovich cluster surveys can be used to constrain cosmological parameters. Extracting clusters from the primary anisotropies and the unresolved background from very faint clusters is simple when the telescope beam size is small (1 arcmin), but could be difficult if the beam is larger (8 arcmin). By reference to examples, we show that this is po

Andrea Gabrielli, Adolfo Paolo Masucci, Francesco Sylos Labini

We study the statistics of the gravitational (Newtonian) force in a particular kind of weakly correlated distribution of point-like and unitary mass particles generated by the so-called Gauss-Poisson point process. In particular we extend to these distributions the analysis a&#39; la Chandrasekhar introduced for purely Poisson processes. In this way we can f

Janusz Gil, George I. Melikidze, Ulrich Geppert

The classical vacuum gap model of Ruderman & Sutherland, in which spark-associated subbeams of subpulse emission circulate around the magnetic axis due to the EB drift, provides a natural and plausible physical mechanism of the subpulse drift phenomenon. Recent progress in the analysis of drifting subpulses in pulsars has provided a strong support to this mo

E. De Donder, D. Vanbeveren

Supernova rates (hypernova, type II, type Ib/c and type Ia) in a particular galaxy depend on the metallicity (i.e. on the galaxy age), on the physics of star formation and on the binary population. In order to study the time evolution of the galactic supernova rates, we use our chemical evolutionary model that accounts in detail for the evolution of single s

Y. Momany, S. Cassisi, G. Piotto, L. R. Bedin

In this paper we report on a curious feature in the V, (U-B) color-magnitude diagrams of globular clusters. In our database, we find that a considerable fraction of blue horizontal branch stars, hotter than the instability strip and cooler than the Grundahl et al. (1999) jump (i.e., 6000 <~ T_eff K <~ 10000), have (U-B) colors redder than their red giant pro

J. Favier, R. Kossakowski, J. P Vialle

The first AMS flight in June 1998 on board of the space shuttle Discovery at an altitude of approximately 380 km unveiled unexpected features of the cosmic rays spectra below the Earth geomagnetic cut-off. In addition to a secondary flux of particles at all latitude, a ring of high energy particles (up to 6 GeV) and an anomalous ratio e+/e- as high as 4 was

S. D. Vrtilek, J. C. Raymond, B. Boroson, R. McCray

We present results from ultraviolet and X-ray observations of the low mass X-ray binary Cygnus X-2. The simultaneous HST/GHRS and ASCA observations took place during the low state of an 82-day cycle. We compare our observations as well as archival IUE and RXTE data with models that predict ultraviolet and optical continuum emission from an X-ray heated disk

P. Janhunen, A. Olsson, R. Karlsson, J. -M. Griessmeier

The motivation to build spaceborne interferometric arrays for low-frequency radio astronomy is widely recognised because frequencies below the ionospheric cutoff are inaccessible for ground-based radio telescopes. We discuss the theoretical possibilities to use low-frequency spacecraft arrays to detect signals from magnetized extrasolar planets, including ea

Gerard Daigne, Jean-Francois Lestrade

Spatial phase-referencing in dual-field optical interferometry is reconsidered. Our analysis is based on the 2-sample variance of the differential phase between target and reference star. We show that averaging over time of the atmospheric effects depends on this 2-sample phase variance (Allan variance) rather than on the true variance. The proper expression

Viacheslav I. Slysh

The radiation broadening of narrow maser lines by its own emission which can be described as resonance Self-Stark effect puts an upper limit on the brightness temperature of cosmic masers. It is shown that available results of measurements of the brightness temperature of OH and water masers are consistent with the observed narrow line widths only if the mas

A. Bershadskii

Multiscaling properties of the Anderson localization of the cosmic electromagnetic fields before the recombination time are studied and results of a numerical simulation for a random banded matrix ensemble are found to be in good agreement with the large-scale cosmic data.

A. Bershadskii

Multiscaling analysis of differential flux dissipation rate of galactic cosmic rays (Carbon nuclei) is performed in the energy ranges: 56.3-73.4 Mev/nucleon and 183.1-198.7 MeV/nucleon, using the data collected by ACE/CRIS spacecraft instrument for 2000 year. The analysis reveals strong (turbulence-like) intermittency of the flux dissipation rate for the sho

N. Masetti, L. Foschini, L. C. Ho, M. Dadina

We report on the identification of the optical and infrared counterparts of the ultraluminous X-ray source (ULX) XMMU J121214.5+131248 (NGC4168-ULX1). The optical spectrum yields a redshift of z=0.217, which implies that the ULX is not associated with the nearby galaxy NGC 4168, but rather with a background object. Optical spectral line ratios and the spectr

C. P. Dullemond, A. Natta

In this paper we investigate how the inclusion of scattering of the stellar radiation into a passive flaring disk model affects its structure and spectral energy distribution, and whether neglecting it could significantly decrease the model reliability. In order to address these questions we construct a detailed 1+1D vertical structure model in which the sca