August 2005 arXiv papers — page 13

Yong-Joo Doh, Jorden A. van Dam, Aarnoud L. Roest, Erik P. A. M. Bakkers

Nanoscale superconductor-semiconductor hybrid devices are assembled from InAs semiconductor nanowires individually contacted by aluminum-based superconductor electrodes. Below 1 K, the high transparency of the contacts gives rise to proximity-induced superconductivity. The nanowires form superconducting weak links operating as mesoscopic Josephson junctions

J. H. Bardarson, J. Tworzydlo, C. W. J. Beenakker

We present an open version of the symplectic kicked rotator as a stroboscopic model of electrical conduction through an open ballistic quantum dot with spin-orbit scattering. We demonstrate numerically and analytically that the model reproduces the universal weak localization and weak anti-localization peak in the magnetoconductance, as predicted by random-m

H. Sarkissian, N. Tabirian, B. Park, B. Zeldovich

A nematic liquid crystal (NLC) layer with the anisotropy axis modulated at a fixed rate q in the transverse direction is considered. If the layer locally constitutes a half-wave plate, then the thin-screen approximation predicts 100% -efficient diffraction of normal incident wave. The possibility of implementing such a layer via anchoring at both surfaces of

Hakob Sarkissian, Chang Ching Tsai, Boris Zeldovich, Nelson Tabirian

Possibility of beam combining and clean-up using Orientational Stimulated Scattering in a Nematic Liquid Crystal is considered. We numerically study the dynamics of the process and find that back-conversion process tends to limit the effective interaction strength. Instability of the steady state of cross-phase modulation is demonstrated, when both waves hav

A. Lodder

The starting formula of Bosvieux and Friedel for the force on an ion in a metal due to an applied voltage is shown to lead to the same description as the linear-response approach used in the field since its introduction by Kumar and Sorbello. By this electromigration theory has become a unified theory. It follows after accounting for a treacherous trap term,

D. Barkley, I. G. Kevrekidis, A. M. Stuart

We explore situations in which certain stochastic and high-dimensional deterministic systems behave effectively as low-dimensional dynamical systems. We define and study moment maps, maps on spaces of low-order moments of evolving distributions, as a means of understanding equations-free multiscale algorithms for these systems. We demonstrate how nonlinearit

A. Donev, J. Burton, F. H. Stillinger, S. Torquato

Previous Monte Carlo investigations by Wojciechowski \emph{et al.} have found two unusual phases in two-dimensional systems of anisotropic hard particles: a tetratic phase of four-fold symmetry for hard squares [Comp. Methods in Science and Tech., 10: 235-255, 2004], and a nonperiodic degenerate solid phase for hard-disk dimers [Phys. Rev. Lett., 66: 3168-31

M. Bowen, A. Barthélémy, M. Bibes, E. Jacquet

We have studied the magnetoresistance (TMR) of tunnel junctions with electrodes of La2/3Sr1/3MnO3 and we show how the variation of the conductance and TMR with the bias voltage can be exploited to obtain a precise information on the spin and energy dependence of the density of states. Our analysis leads to a quantitative description of the band structure of

J. F. Fernandez, J. J. Alonso

We study the relaxation of interacting single--molecule magnets (SMMs) in both spatially ordered and disordered systems. The tunneling window is assumed to be, as in Fe8, much narrower than the dipolar field spread. We show that relaxation in disordered systems differs qualitatively from relaxation in fully occupied cubic and Fe_8 lattices. We also study how

M. V. Milosevic, G. R. Berdiyorov, F. M. Peeters

A rather general enhancement of superconductivity is demonstrated in a hybrid structure consisting of submicron superconducting (SC) sample combined with an in-plane ferromagnet (FM). The superconducting state resists much higher applied magnetic fields for both perpendicular polarities, as applied field is screened by the FM. In addition, FM induces (in the

Robert Spatschek, Miks Hartmann, Efim Brener, Heiner Mueller-Krumbhaar

We present a continuum theory which predicts the steady state propagation of cracks. The theory overcomes the usual problem of a finite time cusp singularity of the Grinfeld instability by the inclusion of elastodynamic effects which restore selection of the steady state tip radius and velocity. We developed a phase field model for elastically induced phase

V. B. Zabolotnyy, S. V. Borisenko, A. A. Kordyuk, J. Fink

The Cu substitution by Zn and Ni impurities and its influence on the mass renormalization effects in angle resolved photoelectron spectra (ARPES) of Bi-2212 is addressed. We show that the nonmagnetic Zn atoms have much stronger effect both in nodal and antinodal parts of the Brillouin zone than magnetic Ni. The observed changes are consistent with the behavi

Xavier Campi, Hubert Krivine

We discuss the meaning of Zipf's law in nuclear multifragmentation. We remark that Zipf's law is a consequence of a power law fragment size distribution with exponent $τ\simeq 2$. We also recall why the presence of such distribution is not a reliable signal of a liquid-gas phase transition.

Hideki Tou, Masahiro Doi, Masafumi Sera, Mamoru Yogi

We report $^{121,123}$Sb nuclear quadrupole resonance (NQR) measurements in the filled-skutterudite superconductor PrOs$_4$Sb$_{12}$ in the temperature range of 0.05-30 K. The electric field gradients (EFG), $V_{zz}$ and $V_{xx}-V_{yy}$, at the Sb site exhibit unusual temperature dependence below 30 K. To explain these features, we discuss the coupling betwe

Z. H. Peng, M. J. Zhang, D. N. Zheng

We propose a experimentally feasible scheme to demonstrate the geometric phase in flux qubits by means of detuning coherent microwave pulse techniques. Through measuring the probability of the persistent current state in flux qubits, one can detect the Berry phase that is acquired with system's Hamiltonian adiabatical circular evolution in the parameter

Michael Kastner, Oliver Schnetz

Exact solutions are obtained for the mean-field spherical model, with or without an external magnetic field, for any finite or infinite number N of degrees of freedom, both in the microcanonical and in the canonical ensemble. The canonical result allows for an exact discussion of the loci of the Fisher zeros of the canonical partition function. The microcano

H. C. Spruit, G. B. Scharmer

We interpret penumbral filaments as due to convection in field-free, radially aligned gaps just below the visible surface of the penumbra, intruding into a nearly potential field above. This solves the classical discrepancy between the large heat flux and the low vertical velocities observed in the penumbra. The presence of the gaps causes strong small-scale

A. A. Suchkov, R. J. Hanisch, Bruce Margon

We have applied ClassX, an oblique decision tree classifier optimized for astronomical analysis, to the homogeneous multicolor imaging data base of the Sloan Digital Sky Survey (SDSS), training the software on subsets of SDSS objects whose nature is precisely known via spectroscopy. We find that the software, using photometric data only, correctly classifies

M. Schroedter, H. M. Badran, J. H. Buckley, J. Bussons Gordo

The BL Lacertae (BL Lac) object 1ES 2344+514 (1ES 2344), at a redshift of 0.044, was discovered as a source of very high energy (VHE) gamma rays by the Whipple Collaboration in 1995 \citep{2344Catanese98}. This detection was recently confirmed by the HEGRA Collaboration \citep{2344Hegra03}. As is typical for high-frequency peaked blazars, the VHE gamma-ray e

A. Atoyan, C. D. Dermer

We have developed a model that explains cosmic rays with energies E between \~0.3 PeV and the energy of the second knee at E_2 ~ 3*10^{17} eV as originating from a recent Galactic gamma-ray burst (GRB) that occurred ~1 Myr ago within 1 kpc from Earth. Relativistic shocks from GRBs are assumed to inject power-law distributions of cosmic rays (CRs) to the high

E. S. Rykoff, S. A. Yost, H. A. Krimm, F. Aharonian

The ROTSE-IIIa telescope at Siding Spring Observatory, Australia, detected prompt optical emission from Swift GRB 050401. In this letter, we present observations of the early optical afterglow, first detected by the ROTSE-IIIa telescope 33 s after the start of gamma-ray emission, contemporaneous with the brightest peak of this emission. This GRB was neither

Philip J. Armitage, Priyamvada Natarajan

Angular momentum loss to circumbinary gas provides a possible mechanism for overcoming the `last parsec' problem and allowing the most massive black hole binaries formed from galactic mergers to coalesce. Here, we show that if gas disks also catalyze the merger of the somewhat lower mass binaries detectable with the Laser Interferometer Space Antenna (LI

R. Blundell

The Submillimeter Array (SMA) was conceived at the Smithsonian Astrophysical Observatory in 1984 as a six element interferometer to operate in the major atmospheric windows from about 200 to 900 GHz. In 1996, the Academica Sinica Institute of Astronomy and Astrophysics of Taiwan joined the project and agreed to provide additional hardware to expand the inter

L. Maltagliati, A. Falchi, L. Teriaca

We studied the evolution of two small flares (GOES class C2 and C1) that developed in the same active region with different morphological characteristics: one is extended and the other is compact. We analyzed the accuracy and the consistency of different algorithms implemented in RHESSI software to reconstruct the image of the emitting sources, for energies

B. Smith, T. Hyde, L. Matthews, J. Reay

In semiconductor manufacturing, contamination due to particulates significantly decreases the yield and quality of device fabrication, therefore increasing the cost of production. Dust particle clouds can be found in almost all plasma processing environments including both plasma etching devices and in plasma deposition processes. Dust particles suspended wi

Christine C. Dantas, Fernando M. Ramos

We present an analysis of the behaviour of the `coarse-grained' (`mesoscopic') rank partitioning of the mean energy of collections of particles composing virialized dark matter halos in a Lambda-CDM cosmological simulation. We find evidence that rank preservation depends on halo mass, in the sense that more massive halos show more rank preservation t

Ben Burningham, Tim Naylor, S. P. Littlefair, R. D. Jeffries

We have investigated the role of photometric variability in causing the apparent age spreads observed in the colour-magnitude diagrams of OB associations. We have found that the combination of binarity, photometric uncertainty and variability on timescales of a few years is not sufficient to explain the observed spread in either of the OB associations we hav

Richard P. Nelson

(Abridged).We present the results of MHD simulations of low mass protoplanets interacting with turbulent disks. We calculate the orbital evolution of `planetesimals&#39; and protoplanets with masses in the range 0 < m_p < 30 M_Earth. Planetesimals and protoplanets undergo stochastic migration due to interaction with turbulent density fluctuations. Over run t

A. Aloisi, R. P. van der Marel, J. Mack, C. Leitherer

We present results from an HST/ACS imaging study of the metal-poor blue compact dwarf galaxy SBS 1415+437. It has been argued previously that this is a very young galaxy that started to form stars only less than 100 Myr ago. However, we find that the optical color-magnitude diagram prominently reveals asymptotic giant branch and red giant branch (RGB) stars.

Cristiano Guidorzi

We test the correlation found by Reichart et al. (2001) between time variability and peak luminosity of Gamma-Ray Bursts (GRBs). Recently Guidorzi et al. (2005) found that this still holds for a sample of 32 GRBs with spectroscopic redshift, although with a larger scatter than that originally found by Reichart et al. (2001). However Guidorzi et al. (2005) al

J. C. Suarez, A. Moya, S. Martin-Ruiz, P. J. Amado

The effect of rotation on the Frequency Ratio Method (Moya et al. 2005) is examined. Its applicability to observed frequencies of rotating gamma Doradus stars is discussed taking into account the following aspects: the use of a perturbative approach to compute adiabatic oscillation frequencies; the effect of rotation on the observational Brunt-Vaisala integr

P. M. Solomon, P. A. Vanden Bout

The Early Universe Molecular Emission Line Galaxies (EMGs) are a population of galaxies with only 36 examples that hold great promise for the study of galaxy formation and evolution at high redshift. The classification, luminosity of molecular line emission, molecular mass, far-infrared (FIR) luminosity, star formation efficiency, morphology, and dynamical m

R. Belmont, M. Tagger, M. Muno, M. Morris

Recent X-ray observations by the space mission Chandra confirmed the astonishing evidence for a diffuse, hot, thermal plasma at a temperature of 9. $10^7$ K (8 keV) found by previous surveys to extend over a few hundred parsecs in the Galactic Centre region. This plasma coexists with the usual components of the interstellar medium such as cold molecular clou

Bernabe Cedres, Jordi Cepa, Akihiko Tomita

We present here a study of the Halpha equivalent widths of the flocculent galaxy NGC 4395 and the grand design galaxy NGC 5457. A difference between the mean values of the Halpha equivalent widths for the two galaxies has been found. Several hypotheses are presented in order to explain this difference: differences in age, metallicity, star formation rate, ph

Daikou Shiota, Hiroaki Isobe, P. F. Chen, Tetsuya T. Yamamoto

We performed magnetohydrodynamic simulation of coronal mass ejections (CMEs) and associated giant arcade formations, and the results suggested new interpretations of observations of CMEs. We performed two cases of the simulation: with and without heat conduction. Comparing between the results of the two cases, we found that reconnection rate in the conductiv

D. A. Gadotti, Ronaldo E. de Souza

The last few years witnessed a change of perspective in the context of galaxy formation and evolution. The major role played by bars in the history of these fundamental building blocks of our universe was finally realized. However, and despite the fact that one of the major concerns of any physical science is to measure timescales for natural phenomena, we h

S. G. Ryan, W. Aoki, J. E. Norris, T. C. Beers

We have compiled composition, luminosity, and binarity information for carbon-enhanced, metal-poor (CEMP) stars reported by recent studies. We divided the CEMP star sample into two classes, having high and low abundances, respectively, of the s-process elements, and consider the abundances of several isotopes, in particular 12C, 13C, and 14N, as well as the

Katsuaki Asano, Fumio Takahara

In the proton counterflow model of a pulsar magnetosphere that we have recently proposed, non-relativistic protons are supplied from the magnetosphere to flow toward the pulsar surface and screen an electric field above the polar cap region. In this Letter, we show that the proton counterflow is also suitable for the bunching of pair plasma. The two-stream i

J. Z. Li, M. D. Smith

The Rosette Molecular Complex contains embedded clusters with diverse properties and origins. We have previously explored the shell mode of formation in the north (Regions A & B) and the massive concentrations in the ridge (Region C). Here, we explore star formation towards the south of the complex, Region D, based on data from the spatially complete 2 Micro

Antonio Peimbert, Manuel Peimbert

The determination of the heavy element abundances from giant extragalactic H II regions has been generally based on collisionally excited lines. We will discuss the reasons to study the characteristics of recombination lines, and then use these lines to determine chemical abundances. Of these lines the oxygen (specifically the O II) lines are the most import

Naoki Yoshida

The currently standard theory of cosmic structure formation posits that the present-day clumpy appearance of the universe developed through gravitational amplification of the matter density fluctuations that are generated in the very early universe. The energy content of the univese and the basic statistics of the initial density field have been determined w

J. Christopher Howk, Kenneth R. Sembach, Blair D. Savage

We describe a new method for determining total gas-phase abundances for the Galactic ISM with minimal ionization uncertainties. For sight lines toward globular clusters containing both UV-bright stars and radio pulsars, one can measure column densities of HI and several metal ions using UV absorption measurements and of H II using radio dispersion measuremen

Diego Blas, Cedric Deffayet, Jaume Garriga

We discuss the causal diagrams of static and spherically symmetric bigravity vacuum solutions, with interacting metrics $f$ and $g$. Such solutions can be classified into type I (or &#34;non-diagonal&#34;) and type II (or &#34;diagonal&#34;). The general solution of type I is known, and leads to metrics $f$ and $g$ in the Schwarzschild-(Anti)de Sitter family

L. Metcalfe, B. O&#39;Halloran, B. McBreen, M. Delaney

Markarian (Mkn) 297 is a complex system with two interacting galaxies. Observations were made with ISO using ISOCAM, ISOPHOT and LWS. We present ISOCAM maps at 6.7, 7.7, 12 and 14.3 microns which, with PHT-S spectrometry of the central interacting region, probe the dust obscured star formation and dust properties. ISOCAM reveals that the strongest emission r

Jason Alicea, Olexei I. Motrunich, Matthew P. A. Fisher

Motivated by inelastic neutron scattering data on Cs_2CuCl_4, we explore spin-1/2 triangular lattice antiferromagnets with both spatial and easy-plane exchange anisotropies, the latter due to an observed Dzyaloshinskii-Moriya interaction. Exploiting a duality mapping followed by a fermionization of the dual vortex degrees of freedom, we find a novel &#34;cri

Gene Guillian

The relative sidereal variation in the arrival direction of primary cosmic ray nuclei of median energy 10 TeV was measured using downward, through-going muons detected with the Super-Kamiokande-I detector. The projection of the anisotropy map onto the right ascension axis has a first harmonic amplitude of $(6.64 \pm 0.98 {stat.} \pm 0.55 {syst.}) \times 10^{

Tai Melcher

This paper discusses the existence of gradient estimates for second order hypoelliptic heat kernels on manifolds. It is now standard that such inequalities, in the elliptic case, are equivalent to a lower bound on the Ricci tensor of the Riemannian metric. For hypoelliptic operators, the associated &#34;Ricci curvature&#34; takes on the value -\infty at poin

Tai Melcher

Let G be a Lie group equipped with a set of left invariant vector fields. These vector fields generate a function ξon Wiener space into G via the stochastic version of Cartan&#39;s rolling map. It is shown here that, for any smooth function f with compact support, f(ξ) is Malliavin differentiable to all orders and these derivatives belong to L^p(μ) for all p

Dumitru Astefanesei, Robert B. Mann, Cristian Stelea

We construct new explicit solutions of general relativity from double analytic continuations of Taub-NUT spacetimes. This generalizes previous studies of 4-dimensional nutty bubbles. One 5-dimensional locally asymptotically AdS solution in particular has a special conformal boundary structure of $AdS_3\times S^1$. We compute its boundary stress tensor and re

Anthony Aguirre, Matthew C. Johnson

This paper examines the classical dynamics of false vacuum regions embedded in surrounding regions of true vacuum, in the thin-wall limit. The dynamics of all generally relativistically allowed solutions -- most but not all of which have been previously studied -- are derived, enumerated, and interpreted. We comment on the relation of these solutions to poss

K. Nomura, J. Wunderlich, Jairo Sinova, B. Kaestner

The controlled generation of localized spin densities is a key enabler of semiconductor spintronics In this work, we study spin Hall effect induced edge spin accumulation in a two-dimensional hole gas with strong spin orbit interactions. We argue that it is an intrinsic property, in the sense that it is independent of the strength of disorder scattering. We

Xiaoan Wu, Scott Tremaine

We describe a maximum-likelihood method for determining the mass distribution in spherical stellar systems from the radial velocities of a population of discrete test particles. The method assumes a parametric form for the mass distribution and a non-parametric two-integral distribution function. We apply the method to a sample of 161 globular clusters in M8

Christian D. Ott, Adam Burrows, Todd A. Thompson, Eli Livne

We present results from an extensive set of one- and two-dimensional radiation-hydrodynamic simulations of the supernova core collapse, bounce, and postbounce phases, and focus on the protoneutron star (PNS) spin periods and rotational profiles as a function of initial iron core angular velocity, degree of differential rotation, and progenitor mass. For the

R. Gueven

We consider the exact solutions of the supergravity theories in various dimensions in which the space-time has the form M_{d} x S^{D-d} where M_{d} is an Einstein space admitting a conformal Killing vector and S^{D-d} is a sphere of an appropriate dimension. We show that, if the cosmological constant of M_{d} is negative and the conformal Killing vector is s

Andrew Ranicki, Desmond Sheiham

The classification of high-dimensional mu-component boundary links motivates decomposition theorems for the algebraic K-groups of the group ring A[F_mu] and the noncommutative Cohn localization Sigma^{-1}A[F_mu], for any mu>0 and an arbitrary ring A, with F_mu the free group on mu generators and Sigma the set of matrices over A[F_mu] which become invertible

V. S. Beskin, S. A. Eliseeva

We analyze the statistical distribution of neutron stars at the stage of a supersonic propeller. An important point of our analysis is allowance for the evolution of the angle of inclination of the magnetic axis to the spin axis of the neutron star for the boundary of the transition to the supersonic propeller stage for two models: the model with hindered pa

Etera R. Livine, Daniel R. Terno

We are interested in black holes in Loop Quantum Gravity (LQG). We study the simple model of static black holes: the horizon is made of a given number of identical elementary surfaces and these small surfaces all behaves as a spin-s system accordingly to LQG. The chosen spin-s defines the area unit or area resolution, which the observer uses to probe the spa

Zoltan Eisler, Janos Kertesz

We reanalyze high resolution data from the New York Stock Exchange and find a monotonic (but not power law) variation of the mean value per trade, the mean number of trades per minute and the mean trading activity with company capitalization. We show that the second moment of the traded value distribution is finite. Consequently, the Hurst exponents for the

Giacomo Raffaelli, Matteo Marsili

We show that financial correlations exhibit a non-trivial dynamic behavior. We introduce a simple phenomenological model of a multi-asset financial market, which takes into account the impact of portfolio investment on price dynamics. This captures the fact that correlations determine the optimal portfolio but are affected by investment based on it. We show

L. Pezze&#39;, A. Smerzi

The paper has been withdrawn by the authors. See newer and expanded version quant-ph/0606221, published in Europhysics Letters 78, 30004 (2007).

M. Payami

In this work, we have used the exchange-only optimized effective potential in the self-consistent calculations of the density functional Kohn-Sham equations for simple metal clusters in stabilized jellium model with self-compression. The results for the closed-shell clusters of Al, Li, Na, K, and Cs with $N=$2, 8, 18, 20, 34, and 40 show that the clusters ar

Claudius Gros

Several guiding principles for thought processes are proposed and a neural-network-type model implementing these principles is presented and studied. We suggest to consider thinking within an associative network built-up of overlapping memory states. We consider a homogeneous associative network as biological considerations rule out distinct conjunction unit

A. J. Clarke, R. D. Oudmaijer, S. L Lumsden

Stars of all evolutionary phases have been found to have excess infrared emission due to the presence of circumstellar material. To identify such stars, we have positionally correlated the infrared MSX point source catalogue and the Tycho 2 optical catalogue. A near/mid infrared colour criteria has been developed to select infrared excess stars. The search y

V. E. Zakharov, A. O. Korotkevich, A. N. Pushkarev, A. I. Dyachenko

We report results of sumulation of wave turbulence. Both inverse and direct cascades are observed. The definition of &#34;mesoscopic turbulence&#34; is given. This is a regime when the number of modes in a system involved in turbulence is high enough to qualitatively simulate most of the processes but significantly smaller then the threshold which gives us q

Lode Wylleman, Norbert Van den Bergh

The \emph{silent universe conjecture} (Sopuerta 1997, van Elst et al. 1997) states that the only algebraically general silent universes are the orthogonally spatially homogeneous Bianchi I models. In the same paper by Sopuerta this was confirmed for the subcase where the spacetime also admits a group G3 of isometries. However the proof contains a conceptual

V. Gogokhia

Using the effective potential approach for composite operators, we have formulated a general method of calculation of the truly nonperturbative Yang-Mills vacuum energy density (the Bag constant apart from the sign, by definition). It is the main dynamical characteristic of the QCD ground state. We define it as an integration of the truly nonperturbative eff

M. Nardini, G. Ghisellini, G. Ghirlanda, F. Tavecchio

We studied the optical afterglows of the 24 pre-Swift Gamma-Ray Bursts with known spectroscopic redshift and published estimates of the optical extinction in the source frame. We find an unexpected clustering of the optical afterglow luminosities measured 12 hours (source frame time) after the trigger. For 21 out of 24 bursts, the distribution of the optical

E. Sezgin, P. Sundell

We give a one-parameter family of exact solutions to four-dimensional higher-spin gauge theory invariant under a deformed higher-spin extension of SO(3,1) and parameterized by a zero-form invariant. All higher-spin gauge fields vanish, while the metric interpolates between two asymptotically AdS4 regions via a dS3-foliated domainwall and two H3-foliated Robe

Ernest Ma

The cubic symmetry S_4 contains A_4 and S_3, both of which have been used to study neutrino mass matrices. Using S_4 as the family symmetry of a complete supersymmetric theory of leptons, it is shown how the requirement of breaking S_4 at the seesaw scale without breaking supersymmetry enforces a special form of the neutrino mass matrix which exhibits maxima

Namit Mahajan

We evaluate the W-exchange diagram within the framework of light cone sum rules (LCSR), taking $B_d^0 \to D_s^-K^+$ as an example. This decay mode, though proceeding via the W-exchange diagram only and therefore expected to be highly suppressed, has the branching ratio $3.2 \times 10^{-5}$. We estimate the W-exchange amplitude within LCSR, including soft glu

Yong Zhou

We improve on Cutkosky&#39;s cutting rules which is used to calculate the contribution of the singularities of Feynman propagators to Feynman amplitude. The correctness of the improved cutting rules is verified by the calculations of the conventional loop momentum integral algorithm. We also find that only the process of the intermediate on shell particles t

Yong Zhou

We discuss the gauge dependence of physical parameter&#39;s definitions under the on-shell and pole mass renormalization prescriptions. By two-loop-level calculations we prove for the first time that the on-shell mass renormalization prescription makes physical result gauge dependent. On the other hand, such gauge dependence doesn&#39;t appear in the result

Martin Kruczenski, Albion Lawrence

We study details of the approach to the Hagedorn temperature in string theory in various static spacetime backgrounds. We show that the partition function for a {\it single} string at finite temperature is the torus amplitude restricted to unit winding around Euclidean time. We use the worldsheet path integral to derive the statement that the the sum over ra

Y. Miyazaki

We have searched for tau lepton decays, tau- -> Lambda-bar pi- and tau- -> Lambda pi-, that simultaneously violate the conservation of the lepton and baryon number using a data sample of 154 fb^{-1} collected with the Belle detector at the KEKB e+e- asymmetric-energy collider. No evidence for a signal was found in either of the decay modes and we set the fol

Michael Freedman, Chetan Nayak, Kirill Shtengel

In this paper we address the question of the existence of a spectral gap in a class of local Hamiltonians. These Hamiltonians have the following properties: their ground states are known exactly; all equal-time correlation functions of local operators are short-ranged; and correlation functions of certain non-local operators are critical. A variational argum

Chai Wah Wu

Recently, Laplacian matrices of graphs are studied as density matrices in quantum mechanics. We continue this study and give conditions for separability of generalized Laplacian matrices of weighted graphs with unit trace. In particular, we show that the Peres-Horodecki positive partial transpose separability condition is necessary and sufficient for separab

Armen E. Allahverdyan, Roger Balian, Theo M. Nieuwenhuizen

In a quantum measurement, a coupling $g$ between the system S and the apparatus A triggers the establishment of correlations, which provide statistical information about S. Robust registration requires A to be macroscopic, and a dynamical symmetry breaking of A governed by S allows the absence of any bias. Phase transitions are thus a paradigm for quantum me

Tien D. Kieu

With a class of quantum heat engines which consists of two-energy-eigenstate systems undergoing, respectively, quantum adiabatic processes and energy exchanges with heat baths at different stages of a cycle, we are able to clarify some important aspects of the second law of thermodynamics. The quantum heat engines also offer a practical way, as an alternativ

Chr. Wunderlich, Th. Hannemann, T. Koerber, H. Haeffner

We report adiabatic passage experiments with a single trapped $^{40}$Ca$^+$ ion. By applying a frequency chirped laser pulse with a Gaussian amplitude envelope we reach a transfer efficiency of 0.990(10) on an optical transition from the electronic ground state S$_{1/2}$ to the metastable state D$_{5/2}$. This transfer method is shown to be insensitive to th

Fernando C. Lombardo, Francisco D. Mazzitelli, Paula I. Villar

Dipoles interference is studied when atomic systems are coupled to classical electromagnetic fields. The interaction between the dipoles and the classical fields induces a time-varying Aharonov-Casher phase. Averaging over the phase generates a suppression of fringe visibility in the interference pattern. We show that, for suitable experimental conditions, t

James P. Clemens, Julio Gea-Banacloche

We consider a two reservoir model of quantum error correction with a hot bath causing errors in the qubits and a cold bath cooling the ancilla qubits to a fiducial state. We consider error correction protocols both with and without measurement of the ancilla state. The error correction acts as a kind of refrigeration process to maintain the data qubits in a

Q. Zhang, J. Yin, T. -Y. Chen, S. Lu

we experimentally implement a fault-tolerant quantum key distribution protocol with two photons in a decoherence-free subspace (DFS). It is demonstrated that our protocol can yield good key rate even with large bit-flip error rate caused by collective rotation, while the usual realization of BB84 protocol cannot produce any secure final key given the same ch

Tien D. Kieu

We introduce a class of quantum heat engines which consists of two-energy-eigenstate systems, the simplest of quantum mechanical systems, undergoing quantum adiabatic processes and energy exchanges with heat baths, respectively, at different stages of a cycle. Armed with this class of heat engines and some interpretation of heat transferred and work performe

T. Keef, A. Taormina, R. Twarock

A vital constituent of a virus is its protein shell, called the viral capsid, that encapsulates and hence provides protection for the viral genome. Assembly models are developed for viral capsids built from protein building blocks that can assume different local bonding structures in the capsid. This situation occurs, for example, for viruses in the family o

T. Keef, C. Micheletti, R. Twarock

The distribution of inequivalent geometries occurring during self-assembly of the major capsid protein in thermodynamic equilibrium is determined based on a master equation approach. These results are implemented to characterize the assembly of SV40 virus and to obtain information on the putative pathways controlling the progressive build-up of the SV40 caps

Anatoly A. Svidzinsky, Marlan O. Scully, Dudley R. Herschbach

It is generally believed that the old quantum theory, as presented by Niels Bohr in 1913, fails when applied to few electron systems, such as the H2 molecule. Here we find new solutions within the Bohr theory that describe the potential energy curve for the lowest singlet and triplet states of H2 about as well as the early wave mechanical treatment of Heitle

Graeme J. Ackland

At the 2005 world championships there was considerable discussion and a formal protest in the long distance race arising from a perceived advantage obtained by some athletes running together. It is shown that a statistical model presented in previous work [1] is applicable to this event, giving predictions of the final times to with 2-3 minutes. Using the mo

James R. Holliday, John B. Rundle, Kristy F. Tiampo, Bill Klein

Recent studies have shown that real-valued principal component analysis can be applied to earthquake fault systems for forecasting and prediction. In addition, theoretical analysis indicates that earthquake stresses may obey a wave-like equation, having solutions with inverse frequencies for a given fault similar to those that characterize the time intervals

James R. Holliday, John B. Rundle, Kristy F. Tiampo, Bill Klein

Recent studies in the literature have introduced a new approach to earthquake forecasting based on representing the space-time patterns of localized seismicity by a time-dependent system state vector in a real-valued Hilbert space and deducing information about future space-time fluctuations from the phase angle of the state vector. While the success rate of

Gordon Chalmers

The analysis of solutions to algebraic equations is further simplified. A couple of functions and their analytic continuation or root findings are required.

Fedor V. Prigara

A transport barrier in a toroidal plasma is treated as the boundary region between the hot and cold phases of the plasma. These two phases possess essentially different collisional and transport properties, so the boundary region between them corresponds to the minimum values of specific resistivity and transport coefficients of the plasma. The behavior of m

L. Zamick, A. Escuderos

We had previously used techniques involving isospin to count the number of states for three identical fermions in a single j shell with total angular momentum I=j. We generalize this to all I, but the main thrust of this work is to consider now a 4-fermion system. As before, one evaluates the eigenvalues of the Hamiltonian \sum_{i<j}[a + bt(i)t(j)] both from

Edgar Teran, Calvin W. Johnson

An important input into reaction theory is the density of states or the level density. Spectral distribution theory (also known as nuclear statistical spectroscopy) characterizes the secular behavior of the density of states through moments of the Hamiltonian. One particular approach is to partition the model space into subspaces and find the moments in thos

Johanna Stachel

This paper gives highlights of the experimental results shown at this conference.

P. Braun-Munzinger

We update briefly our understanding of hadron production in relativistic nucleus-nucleus collisions in terms of statistical models with emphasis on the relation of the data to the QCD phase boundary and on a puzzle in the beam energy dependence.

Subhasis Chattopadhyay

A method has been proposed for the determination of $γ$ to $π^0$ ratio in high energy pp and nucleus-nucleus collisions at large transverse momentum ($p_T$). In photon measuring device, it is proposed that shower shape analysis is made to select only cases with wide showers. These candidates come mostly from $π^0$. Correlation is measured between those photo

S. Y. Lou, Bin Tong, Heng-chun Hu, Xiao-yan Tang

Some types of coupled Korteweg de-Vries (KdV) equations are derived from an atmospheric dynamical system. In the derivation procedure, an unreasonable $y$-average trick (which is usually adopted in literature) is removed. The derived models are classified via Painlevé test. Three types of $τ$-function solutions and multiple soliton solutions of the models ar

H. W. Schuermann, V. S. Serov, J. Nickel

Real and bounded elliptic solutions suitable for applying the Khare-Sukhatme superposition procedure are presented and used to generate superposition solutions of the generalized modified Kadomtsev-Petviashvili equation (gmKPE) and the nonlinear cubic-quintic Schroedinger equation (NLCQSE).

T. V. Dudnikova, A. I. Komech, H. Spohn

Consider the wave equation with constant or variable coefficients in $\R^3$. The initial datum is a random function with a finite mean density of energy that also satisfies a Rosenblatt- or Ibragimov-Linnik-type mixing condition. The random function converges to different space-homogeneous processes as $x_3\to\pm\infty$, with the distributions $μ_\pm$. We st

V. I. Zhdanov, M. S. Borshch

We obtain criteria for shock wave (SW)existence in relativistic magnetic hydrodynamics with no suppositions about convexity of the equation of state. Method of derivation involves consideration of a continuous SW profile in presence of Landau-Lifshitz relativistic viscosity tensor with both non-zero viscosity coefficients.