April 2003 arXiv papers — page 11

M. Arik, U. Kayserilioglu

The particle algebras generated by the creation/annihilation operators for bosons and for fermions are shown to possess quantum invariance groups. These structures and their sub(quantum)groups are investigated.

H. Itoyama, H. Kanno

We present a variant of the supereigenvalue model proposed before by Alvarez-Gaume, Itoyama, Manes, and Zadra. This model derives a set of three planar loop equations which takes the same form as the set of three anomalous Ward-Takahashi identities on the gaugino condensates recently derived by Cachazo, Douglas, Seiberg and Witten. Another model which implem

Tamiaki Yoneya

The issue of holographic principle in the PP-wave limit of the AdS/CFT correspondence is discussed, in the hope of clarifying some confusions in the literature. We show that, in the plane-wave limit, the relation between the partition function in the bulk and the gauge-invariant correlation functions on the boundary should be interpreted on the basis of a tu

J. L. Diaz-Cruz, D. A. Lopez-Falcon

A definition of the rho parameter based on the Higgs couplings with the gauge bosons, rho_h= g_{hWW}}/c^2_W g_{hZZ}, is proposed as a new probe into the origin of the mechanism of electroweak symmetry breaking. While $ρ_h=1$ holds in the SM, deviations from one are predicted in models with extended Higgs sector. We derive a general expresion of rho_h for a m

Michele Gallinaro

First QCD results obtained from the CDF experiment using Run II data are reported. The Run II physics program at the Tevatron started in the spring of 2001, with protons and anti-protons colliding at an energy of sqrt(s) = 1.96 TeV. The size of the data sample already compares to that of Run I. Results presented here include the measurement of the inclusive

S. I. Alekhin, S. A. Kulagin, S. Liuti

We present results of a perturbative QCD analysis of deep inelastic measurements of both the deuteron and proton structure functions. We evaluate the theoretical uncertainty associated to nuclear effects in the deuteron, and we extract simultaneously the isospin depedendence of: i)the higher twists terms; ii) the ratio of the longitudinal to transverse cross

M. K. Suleymanov, M. Sumbera, I. Zborovsky

Using three different Monte Carlo generators of high energy proton-proton collisions (HIJING, NEXUS, and PSM) we study the energy dependence of multiplicity distributions of charged particles including the LHC energy range. Results are used for calculation of the information entropy, Renyi's dimensions and other multifractal characteristics of particle p

R. Aleksan, P. F. Giraud, V. Morenas, O. Pene

Trying a global fit of the experimental branching ratios and CP-asymmetries of the charmless $B\to PV$ decays according to QCD factorization, we find it impossible to reach a satisfactory agreement, the confidence level (CL) of the best fit is smaller than .1 %. This failure reflects the difficulty to accommodate several large experimental branching ratios o

Tatsu Takeuchi, Will Loinaz, Naotoshi Okamura, L. C. R. Wijewardhana

The Z-pole data from e+e- colliders and results from the NuTeV experiment at Fermilab can be brought into agreement if (1) the neutrino-Z couplings were suppressed relative to the Standard Model (SM), and (2) the Higgs boson were much heavier than suggested by SM global fits. However, increasing the Higgs boson mass will move the theoretical value of the W m

N. N. Achasov

It is argued that the search of the J/psi --> f0(980)omega and J/psi --> a0(980)rho decays and the more precise definition of B(J/psi --> f0(980)phi) are the urgent purposes in the J/ψspectroscopy. It is shown that the study of the omega-rho0 interference pattern in the J/psi --> (ρ^0+ω)eta --> pi+pi-eta decay provides evidence for the large (nearly pi/2) re

T. Hadig

The DIRC, a novel type of Cherenkov ring imaging device, is the primary hadronic particle identification system for the BaBar detector at the asymmetric B-factory Pep-II at SLAC. It is based on total internal reflection and uses long, rectangular bars made from synthetic fused silica as Cherenkov radiators and light guides. BaBar began taking data with colli

V. V. Anisimovsky, A. N. Khotjantsev, A. P. Ivashkin

We present the result of the first measurement of the T-violating muon polarization P_T in the decay K^+ --> mu^+ nu gamma. This polarization is sensitive to new sources of CP-violation in the Higgs sector. Using data accumulated in the period 1996-98 we have obtained P_T = (-0.64 +- 1.85(stat) +- 0.10(syst))x10^{-2} which is consistent with no T-violation i

M. W. Choptuik, L. Lehner, I. Olabarrieta, R. Petryk

Black strings, one class of higher dimensional analogues of black holes, were shown to be unstable to long wavelength perturbations by Gregory and Laflamme in 1992, via a linear analysis. We revisit the problem through numerical solution of the full equations of motion, and focus on trying to determine the end-state of a perturbed, unstable black string. Our

Harihar Behera, P. C. Naik

The gravitational effects in the relativistic quantum mechanics are investigated in a relativistically derived version of Heaviside's speculative Gravity (in flat space-time) named here as Maxwellian Gravity. The standard Dirac's approach to the intrinsic spin in the fields of Maxwellian Gravity yields the gravitomagnetic moment of a Dirac (spin 1/2)

G. Papini

Covariant generalizations of well-known wave equations predict the existence of inertial-gravitational effects for a variety of quantum systems that range from Bose-Einstein condensates to particles in accelerators. Additional effects arise in models that incorporate Born reciprocity principle and the notion of a maximal acceleration. Some specific examples

S. S. Xulu

The event horizon of a charged black hole is, according to Ruffini\cite{Ruffini} and Preparata \emph{et al.}\cite{PreparataEtAl}, surrounded by a special region called the \emph{dyadosphere} where the electromagnetic field exceeds the Euler-Heisenberg critical value for electron-positron pair production. We obtain the energy distribution in the dyadosphere r

Patrick J. McCarthy, R. L. Schafir

Magueijo and Smolin have introduced a modification of the Lorentz group for the momentum-space transformations in Doubly-Special Relativity. As presented the group is non-linear, but we show that it is a group of fraction-linear transformations in 4 dimensional real projective space. We pass to the associated 5 dimensional linear space and identify the subgr

F. G. Alvarenga, A. B. Batista, J. C. Fabris, S. V. B. Gonçalves

The anisotropic Bianchi I cosmological model coupled with perfect fluid is quantized in the minisuperspace. The perfect fluid is described by using the Schutz formalism which allows to attribute dynamical degrees of freedom to matter. A Schrödinger-type equation is obtained where the matter variables play the role of time. However, the signature of the kinet

S. G. Ghosh, D. W. Deshkar

We investigate the occurrence and nature of naked singularities in the gravitational collapse of an adiabatic perfect fluid in self-similar higher dimensional space-times. It is shown that strong curvature naked singularities could occur if the weak energy condition holds. Its implication for cosmic censorship conjecture is discussed. Known results of analog

Douglas A. Galbi

Radio technology seems destined to become part of the standard micro-processor input/output system. But unlike for memory or display systems, for radio systems government regulation matters a lot. Much discussion of radio regulation has focused on narrow spectrum management and interference issues. Reflecting on historical experience and centuries of convers

Douglas A. Galbi

To contribute to understanding of information economies of daily life, this paper explores over the past millennium given names of a large number of persons. Analysts have long both condemned and praised mass media as a source of common culture, national unity, or shared symbolic experiences. Names, however, indicate a large decline in shared symbolic experi

Douglas A. Galbi

An acceleration in the growth of communications bandwidth in use and a rapid reduction in bandwidth prices have not accompanied the U.S. economy's strong performance in the second half of the 1990s. Overall U.S. bandwidth in use has grown robustly throughout the 1990s, but growth has not significantly accelerated in the second half of 1990s. Average pric

Douglas A. Galbi

Vibrant development of a network-based economy requires separating investment in highly location specific local access technology from the development of standardized, geography-independent, wide-area network services. Thus far interconnection arrangements and associated regulations have been too closely tied to the idiosyncratic geographic structure of indi

John M. Hitchcock

Juedes and Lutz (1995) proved a small span theorem for polynomial-time many-one reductions in exponential time. This result says that for language A decidable in exponential time, either the class of languages reducible to A (the lower span) or the class of problems to which A can be reduced (the upper span) is small in the sense of resource-bounded measure

Dietmar Roesner, Manuela Kunze

We report about the current state of development of a document suite and its applications. This collection of tools for the flexible and robust processing of documents in German is based on the use of XML as unifying formalism for encoding input and output data as well as process information. It is organized in modules with limited responsibilities that can

Baden Hughes, Steven Bird

We describe a proposal for an extensible, component-based software architecture for natural language engineering applications. Our model leverages existing linguistic resource description and discovery mechanisms based on extended Dublin Core metadata. In addition, the application design is flexible, allowing disparate components to be combined to suit the o

J. C. Phillips

A ferroelastic nanoscopic checkerboard pattern of pseudo- and superconductive gaps has been resolved by scanning tunneling microscopy on BSCCO. Using this pattern one can derive [not assume] a macroscopic anisotropic d wave superconductive energy gap that agrees well with angle-resolved photoemission and Fourier transform scanning tunneling microscopy data.

J. C. Phillips

Fourier transform scanning tunneling microscopy on BSCCO subgap resonances has deciphered an octet of "quasi-particle" states that are consistent with the Fermi surface and energy gap observed by ARPES, but the origin of the high-intensity k-space octets and the sharply defined r-space checkerboard is unexplained. The filamentary ferroelastic nanodom

Etienne Boaknin, M. A. Tanatar, Johnpierre Paglione, D. G. Hawthorn

The thermal conductivity of the layered s-wave superconductor NbSe_2 was measured down to T_c/100 throughout the vortex state. With increasing field, we identify two regimes: one with localized states at fields very near H_c1 and one with highly delocalized quasiparticle excitations at higher fields. The two associated length scales are most naturally explai

Mike Sutherland, D. G. Hawthorn, R. W. Hill, F. Ronning

Thermal transport in the T -> 0 limit was measured as a function of doping in high-quality single crystals of the cuprate superconductor YBa_2Cu_3O_y. The residual linear term kappa_0/T is found to decrease as one moves from the overdoped regime towards the Mott insulator region of the phase diagram. The doping dependence of the low-energy quasiparticle gap

Johnpierre Paglione, M. A. Tanatar, D. G. Hawthorn, Etienne Boaknin

The resistivity of CeCoIn_5 was measured down to 20 mK in magnetic fields of up to 16 T. With increasing field, we observe a suppression of the non-Fermi liquid behavior, rho~T, and the development of a Fermi liquid state, with its characteristic rho=rho_0+AT^2 dependence. The field dependence of the T^2 coefficient shows critical behavior with an exponent o

Claudia S. Peca, Leon Balents, Kay Wiese

We study the two-terminal transport properties of a metallic single-walled carbon nanotube with good contacts to electrodes, which have recently been shown [W. Liang et al, Nature 441, 665-669 (2001)] to conduct ballistically with weak backscattering occurring mainly at the two contacts. The measured conductance, as a function of bias and gate voltages, show

D. G. Hawthorn, R. W. Hill, F. Ronning, Mike Sutherland

The transport of heat and charge in cuprates was measured in undoped and heavily-underdoped single crystal La_{2-x}Sr_xCuO_{4+delta} (LSCO). In underdoped LSCO, the thermal conductivity is found to decrease with increasing magnetic field in the T --> 0 limit, in striking contrast to the increase observed in all superconductors, including cuprates at higher d

Maxim Mostovoy, Daniel Khomskii

We discuss a new mechanism of orbital ordering, which in charge transfer insulators is more important than the usual exchange interactions and which can make the very type of the ground state of a charge transfer insulator, i.e. its orbital and magnetic ordering, different from that of a Mott-Hubbard insulator. This purely electronic mechanism allows us to e

Alexander Weisse, Holger Fehske

We report on the influence of the lattice degrees of freedom on charge, orbital and spin correlations in colossal magnetoresistance (CMR) manganites. For the weakly doped compounds we demonstrate that the electron-phonon coupling promotes the trapping of charge carriers, the disappearance of the orbital polaron pattern and the breakdown of ferromagnetism at

A. Pautrat, A. Daignere, C. Goupil, Ch. Simon

We report complex impedance measurements in an untwinned YBaCuO crystal. Our broad frequency range covers both the quasi static response and the resistive response of the vortex lattice. It allow us to characterize the irreversibility line without the need of any frequency dependent pinning parameters. We confirm the validity of the two modes model of vortex

Young-June Kim, J. P. Hill, F. C. Chou, D. Casa

We report a resonant inelastic x-ray scattering study of electronic excitations in Li_2CuO_2, an insulating compound comprised of ribbons of edge-sharing copper-oxygen chains. Three excitations, which show little dependence on momentum transfer, are observed in our measurements. The lowest energy excitation at ~2.1 eV is dispersionless and is attributed to a

Gregory Schehr, Pierre Le Doussal

We extend the exact multilocal renormalization group (RG) method to study the flow of the effective action functional. This important physical quantity satisfies an exact RG equation which is then expanded in multilocal components. Integrating the nonlocal parts yields a closed exact RG equation for the local part, to a given order in the local part. The met

Jörn Davidsen, István Z. Kiss, John L. Hudson, Raymond Kapral

Numerical and experimental evidence is presented to show that many phase synchronized systems of non-identical chaotic oscillators, where the chaotic state is reached through a period-doubling cascade, show rapid convergence of the time-averaged frequency. The speed of convergence toward the natural frequency scales as the inverse of the measurement period.

Hisatsugu Yamasaki, Yuhei Natsume, Akira Terai, Katsuhiro Nakamura

We investigate the $E_g \otimes e_g$ Jahn-Teller system for the purpose to reveal the nature of quantum chaos in crystals. This system simulates the interaction between the nuclear vibrational modes and the electronic motion in non-Kramers doublets for multiplets of transition-metal ions. Inclusion of the anharmonic potential due to the trigonal symmetry in

T. Machi, I. Kato, R. Hareyama, N. Watanabe

The effects of nonmagnetic Zn and magnetic Ni substitution for Cu site on magnetism are studied by measurements of uniform magnetic susceptibility for lightly doped La_{2-x}Sr_xCu_{1-z}M_zO_4 (M=Zn or Ni) polycrystalline samples. For the parent x=0, Zn doping suppresses the Néel temperature T_N whereas Ni doping hardly changes T_N up to z=0.3. For the lightl

A. N. Lavrov, Seiki Komiya, Yoichi Ando

Resistivity and magnetization measurements are used for studying the transverse sliding of AF domain boundaries in lightly doped La_{2-x}Sr_{x}CuO_{4}. We discuss that it is the freezing of the transverse boundary motion that is responsible for the appearance of ``spin-glass'' features at low temperatures.

T. Motohashi, M. Karppinen, H. Yamauchi

The sodium-cobalt oxide NaxCoO2+d is a promising candidate for thermoelectric applications since it may possess simultaneously large thermoelectric power and low resistivity. It is difficult to understand the simultaneous appearance of the two properties within the framework of conventional one-electron models. It has been suggested that the spin state of co

V. Ferrando, C. Bernini, P. Manfrinetti, D. Marre'

Critical fields of four MgB2 thin films with a normal state resistivity ranging from 5 to 50 mWcm and Tc from 29.5 to 38.8 K were measured up to 28 T. Hc2(T) curves present a linear behavior towards low temperatures. Very high critical field values have been found, up to 24 T along the c-axis and 57 T in the basal plane not depending on the normal state resi

H. Yamagata, H. Miyamoto, K. Nakamura, M. Matsumura

We studied Zn-substitution effect on the high-T_c superconductors, underdoped La_{2-x}Sr_xCu_{1-y}Zn_yO_4 (x=0.10; y=0, 0.01, 0.02), optimally doped (x=0.15; y=0, 0.02), and overdoped (x=0.20; y=0, 0.03, 0.06) in a temperature range of T=4.2-300 K, using Cu nuclear quadrupole resonance (NQR) spin-echo technique. We found full disappearance of the Cu NQR sign

Go Kato, Masahiro Shiroishi, Minoru Takahashi, Kazumitsu Sakai

The correlation functions of the spin-1/2 XXZ spin chain in the ground state are expressed in the form of the multiple integrals. For -1< Delta <1, they were obtained by Jimbo and Miwa in 1996. Especially the next nearest-neighbour correlation functions are given as certain three-dimensional integrals. We shall show these integrals can be reduced to one-dime

Yoji Ohashi

We investigate nonmagnetic impurity effects in two-band superconductors, focusing on the effects of interband scatterings. Within the Born approximation, it is known that interband scatterings mix order parameters in the two bands. In particular, only one averaged energy gap appears in the excitation spectrum in the dirty limit. [G. Gusman: J. Phys. Chem. So

Igor Zutic, Jaroslav Fabian

In an inhomogeneously doped magnetic semiconductor, an interplay between an equilibrium magnetization and injected nonequilibrium spin leads to the spin-voltaic effect--a spin analogue of the photo-voltaic effect. By reversing either the sign of the equilibrium magnetization or the direction of injected spin polarization it is possible to switch the directio

Oron Zachar

We introduce a new model and mechanism of high temperature pairing in stripes. We propose a way to unambiguously test it by numerical simulations. For example, the implementation of our mechanism in a 6-leg t-J ladder model has the effect of making the spin gap of the doped 6-leg ladder be about 4 times bigger than the spin gap of the same ladder at half fil

H. H. Wen, H. P. Yang, X. F. Lu, J. Yan

The paper has been withdrawn due to very low reproducibility. About 100 samples have been made, only 3 samples show the superconducting-like behavior. We think it may be an unlikely result.

Shaul Mukamel

The relation between the distribution of work performed on a classical system by an external force switched on an arbitrary timescale, and the corresponding equilibrium free energy difference, is generalized to quantum systems. Using the adiabatic representation we show that this relation holds for isolated systems as well as for systems coupled to a bath de

Yunkyu Bang

We propose a variational wave function for the ground state of the magnetic heavy fermion (HF) systems, in which both the Kondo and the RKKY interactions are variationally incorporated and the local f-orbital state exists as a linear combination of a full local moment state and a fully compensated state (mixed moment state). We describe the mechanism for the

James D. Brownridge, Sol Raboy

Experimental observations of the change in the polarization charge of pyroelectric crystals of LiNbO3, LiTaO3 and CsNO3, as the temperature of the crystal is changed from about 300K to a lower limit of 4.2K, are described. It was found that the rate of change of the polarization charge slowed down considerably and, perhaps, reached a zero rate of change. The

D. N. Monin, G. A. Wade, S. N. Fabrika

Two newly identified Ae stars, nu Cyg and kappa UMa, were discovered in the course of the Magnetic Survey of Bright MS stars (Monin et al. 2002). We pre sent their Halpha profiles along with measurements of their equivalent width and parameters of emission features. Emission in the Halpha line of nu Cyg is variable on a time scale of 3 years. kappa UMa exhib

T. L. Aldcroft, P. J. Green

We have obtained a 110 ksec Chandra ACIS-S exposure of UM425, a pair of QSOs at z=1.47 separated by 6.5 arcsec, which show remarkably similar emission and broad absorption line (BAL) profiles in the optical/UV. Our 5000 count X-ray spectrum of UM425A (the brighter component) is well-fit with a power law (photon spectral index Gamma=2.0) partially covered by

Kate Y. L. Su, Bruce J. Hrivnak, Sun Kwok, Raghvendra Sahai

High-resolution near-infrared HST NICMOS (F160W, F222M) images and polarization (2 um) observations were made of four bipolar proto-planetary nebulae (PPNs): IRAS 17150-3224, IRAS 17441-2411, IRAS 17245-3951, and IRAS 16594-4656. The first three of these are viewed nearly edge-on, and for the first time the central stars in them are seen. Color maps reveal a

Karen T. Lewis, Michael Eracleous, Rita M. Sambruna

A handful of well-studied Weak-Line Radio Galaxies (WLRGs) have been traditionally classified as Low Ionization Nuclear Emission-line Regions (LINERs), suggesting that these two groups of AGNs might be related. In this paper, we present new optical emission-line measurements for twenty Weak-Line Radio Galaxies which we supplement with measurements for an add

M. Galeazzi, D. McCammon

The standard non-equilibrium theory of noise in ideal bolometers and microcalorimeters fails to predict the performance of real devices due to additional effects that become important at low temperature. In this paper we extend the theory to include the most important of these effects, and find that the performance of microcalorimeters operating at 60 mK can

Asantha Cooray

There are several observational campaigns under way to detect kilometer size foreground Kuiper Belt Objects (KBOs) through their occultation of background stars. The interpretation of an occultation light curve, unfortunately, is affected by a geometric degeneracy such that one is unable to determine the KBO size independent of its distance. This degeneracy

B. F. Vitorino, V. Jatenco-Pereira, R. Opher

We present 2.5-dimensional time-dependent simulations of nonrelativistic and nonradiative outflows from sinusoidally perturbed Keplerian accretion disks. A sinusoidal perturbation is introduced in the velocity of the gas ejected from the surface of the disk into a cold corona. In the simulations, the disk is a fixed boundary from which the gas is ejected wit

D. M. Alexander, F. E. Bauer, W. N. Brandt, D. P. Schneider

We present catalogs for the ~2 Ms Chandra Deep Field-North, currently the deepest X-ray observation of the Universe in the 0.5-8.0 keV band. Five hundred and three (503) X-ray sources are detected over an ~448 sq.arcmin area in up to seven bands; 20 of these X-ray sources lie in the Hubble Deep Field-North. Source positions are determined using matched-filte

M. S. Dimitrijevic, T. Ryabchikova, L. C. Popovic, D. Shulyak

We study the influence of Stark broadening and stratification effects on Siılines in the rapidly oscillating (roAp) star 10 Aql, where the Siı6142.48 Åand 6155.13 Ålines are asymmetrical and shifted. First we have calculated Stark broadening parameters using the semiclassical perturbation method for three Siılines: 5950.2 Å, 6142.48 Åand 6155.13 Å. We revise

L. C. Popovic

Using a well known method for laboratory plasma diagnostic, the Boltzmann-plot, we discuss the physical properties in Broad Line Region (BLR) of Active Galactic Nuclei (AGN). We apply the Boltzmann-plot method to Balmer lines on a sample of 14 AGN, finding that it may indicate the existence of &#34;Case B&#34; recombination or Partial Local Thermodynamical E

Stephen S. Eikenberry, Maurice H. H. M. van Putten

We present a magnetic bomb scenario for the multiwavelength behavior during &#34;Type B&#34; relativistic jet events in the microquasar GRS 1915+105. These events are characterized by a hard X-ray dip which terminates in a soft X-ray spike. The scenario, based on the suspended accretion model for long gamma-ray bursts, posits a magnetic dynamo around an accr

Harald~Krüger, Alexander V. Krivov, Miodrag Sremčević, Eberhard Grün

Tenuous dust clouds of Jupiter&#39;s Galilean moons Io, Europa, Ganymede and Callisto have been detected with the in-situ dust detector on board the Galileo spacecraft. The majority of the dust particles have been sensed at altitudes below five radii of these lunar-sized satellites. We identify the particles in the dust clouds surrounding the moons by their

D. Monnier Ragaigne, W. van Driel, S. E. Schneider, T. H. Jarrett

A sample of about 3,800 Low Surface Brightness (LSB) galaxies was selected using the all-sky near-infrared (J, H and K_s-band) 2MASS survey. The selected objects have a mean central surface brightness within a 5 arcsec radius around their centre fainter than 18 mag/sq.arcsec in the K_s band, making them the lowest surface brightness galaxies detected by 2MAS

E. Bica, C. M. Dutra, J. Soares, B. Barbuy

We carried out a survey of infrared star clusters and stellar groups on the 2MASS J, H and K_s all-sky release Atlas in the Northern and Equatorial Milky Way (350 < l < 360, 0 < l < 230). The search in this zone complements that in the Southern Milky Way (Dutra et al. 2003a). The method concentrates efforts on the directions of known optical and radio nebula

Naohisa Inada, Robert H. Becker, Scott Burles, Francisco J. Castander

We report the discovery of a new gravitationally lensed quasar from the Sloan Digital Sky Survey, SDSS J092455.87+021924.9 (SDSS J0924+0219). This object was selected from among known SDSS quasars by an algorithm that was designed to select another known SDSS lensed quasar (SDSS 1226-0006A,B). Five separate components, three of which are unresolved, are iden

Lorne A. Nelson, Saul Rappaport

We examine a number of evolutionary scenarios for the recently discovered class of accretion-powered millisecond X-ray pulsars in ultracompact binaries, including XTE J0929-314 and XTE J1751-305, with orbital periods of 43.6 and 42.4 minutes, respectively. We focus on a particular scenario that can naturally explain the present-day properties of these system

Neil Shenvi, Kenneth R. Brown, K. Birgitta Whaley

Grover&#39;s algorithm provides a quadratic speed-up over classical algorithms for unstructured database or library searches. This paper examines the robustness of Grover&#39;s search algorithm to a random phase error in the oracle and analyzes the complexity of the search process as a function of the scaling of the oracle error with database or library size

C. Aubin, C. Bernard

We show how to compute chiral logarithms that take into account both the $\cO(a^2)$ taste-symmetry breaking of staggered fermions and the fourth-root trick that produces one taste per flavor. The calculation starts from the Lee-Sharpe Lagrangian generalized to multiple flavors. An error in a previous treatment by one of us is explained and corrected. The one

William M. Goldman

The SL(2)-character variety X of a closed surface M enjoys a natural complex-symplectic structure invariant under the mapping class group G of M. Using the ergodicity of G on the SU(2)-character variety, we deduce that every G-invariant meromorphic function on X is constant. The trace functions of closed curves on M determine regular functions which generate

Hae-Young Kee, Eugene H. Kim, Chung-Hou Chung

The electronic nematic phase occurs when the point-group symmetry of the lattice structure is broken, due to electron-electron interactions. We study a model for the nematic phase on a square lattice with emphasis on the phase transition between isotropic and nematic phases within mean field theory. We find the transition to be first order, with dramatic cha

A. Ignatov, S. Y. Savrasov, T. A. Tyson

To understand the role of electron-phonon interaction in superconducting MgCNi$_{3}$ we have performed density functional based linear response calculations of its lattice dynamical properties. A large coupling constant $% λ$= 1.51 is predicted and contributing phonons are identified as displacements of Ni atoms towards octahedral interstitials of the perovs

Carsten Honerkamp

Motivated by the recent finding of superconductivity in layered CoO_2 compounds, we investigate superconducting and magnetic instabilities of interacting electrons on the two-dimensional triangular lattice. Using a one-loop renormalization group scheme for weak to moderate coupling strengths, we find that for purely local interactions U>0 and small Fermi sur

Yu Shi, Yong-Shi Wu

Adiabatic limit is the presumption of the adiabatic geometric quantum computation and of the adiabatic quantum algorithm. But in reality, the variation speed of the Hamiltonian is finite. Here we develop a general formulation of adiabatic quantum computing, which accurately describes the evolution of the quantum state in a perturbative way, in which the adia

O. Chavoya-Aceves

A de Broglie-Bohm like model of Klein-Gordon equation, that leads to the correct Schrodinger equation in the low-speed limit, is presented. Under this theoretical framework, that affords an interpretation of the quantum potential, the main assumption of the de Broglie-Bohm interpretation--that the local momentum of particles is given by the gradient of the p

Abhay Ashtekar, Martin Bojowald, Jerzy Lewandowski

Applications of Riemannian quantum geometry to cosmology have had notable successes. In particular, the fundamental discreteness underlying quantum geometry has led to a natural resolution of the big bang singularity. However, the precise mathematical structure underlying loop quantum cosmology and the sense in which it implements the full quantization progr

S. J. Summers, R. K. White

We prove that, under suitable assumptions, operationally motivated data completely determine a space-time in which the quantum systems can be interpreted as evolving. At the same time, the dynamics of the quantum system is also determined. To minimize technical complications, this is done in the example of three-dimensional Minkowski space.

John B. Little

The order domains are a class of commutative rings introduced by Høholdt, van Lint, and Pellikaan to simplify the theory of error control codes using ideas from algebraic geometry. The definition is largely motivated by the structures utilized in the Berlekamp-Massey-Sakata (BMS) decoding algorithm, with Feng-Rao majority voting for unknown syndromes, applie

Alexei Morozov, Antti J. Niemi

The field theoretical renormalization group equations have many common features with the equations of dynamical systems. In particular, the manner how Callan-Symanzik equation ensures the independence of a theory from its subtraction point is reminiscent of self-similarity in autonomous flows towards attractors. Motivated by such analogies we propose that be

Shijun Yoshida, Umin Lee

We discuss the modal properties of the $r$-modes of relativistic superfluid neutron stars, taking account of the entrainment effects between superfluids. In this paper, the neutron stars are assumed to be filled with neutron and proton superfluids and the strength of the entrainment effects between the superfluids are represented by a single parameter $η$. W

Chiang-Mei Chen, Pei-Ming Ho, Ishwaree P. Neupane, John E. Wang

We study compactifications of Einstein gravity on product spaces in vacuum and their acceleration phases. Scalar potentials for the dimensionally reduced effective theory are found to be of exponential form and exact solutions are obtained for a class of product spaces. The inflation in our solutions is not sufficient for the early universe. We comment on th

A. S. Galoyan, A. Polanski

This paper proposes to apply the Ultra-Relativistic Quantum Molecular Dynamic (UrQMD) approach to implement the PANDA project (GSI). Modeling of $\bar{p}$A-interactions has been performed at antiproton energies from 1 GeV to 200 GeV by using the UrQMD model. We have studied average multiplicities, multiplicity distributions of various types of secondary part

A. Lengyel, M. V. T. Machado

We perform an adjust to the most recent structure function data, considering the QCD dipole picture applied to ep scattering. The structure function F2 at small x and intermediate Q2 can be described by the model containing an economical number of free-parameters, which encodes the hard Pomeron physics. The longitudinal structure function and the gluon distr

M. A. McLaughlin, J. M. Cordes

We discuss the giant-pulse phenomenon exhibited by pulsars and the distances to which giant pulses might be detected from extragalactic pulsars. We describe the conditions under which a single-pulse search is more sensitive than a standard periodicity search. We find that, for certain pulse-amplitude distribution power laws and time series lengths, single-pu

Steven C. Erwin, I. I. Mazin

The two-gap model for superconductivity in MgB2 predicts that interband impurity scattering should be pair breaking, reducing the critical temperature. This is perhaps the only prediction of the model that has not been confirmed experimentally. It was previously shown theoretically that common substitutional impurities lead to negligible interband scattering

J. M. Cordes, M. A. McLaughlin

We discuss optimal detection of fast radio transients from astrophysical objects while taking into account the effects of propagation through intervening ionized media, including dispersion, scattering and scintillation.Our analysis applies to the giant-pulse phenomenon exhibited by some pulsars, for which we show examples, and to radio pulses from other ast

Andrew V. Goldberg, Alexander V. Karzanov

The maximum integer skew-symmetric flow problem (MSFP) generalizes both the maximum flow and maximum matching problems. It was introduced by Tutte in terms of self-conjugate flows in antisymmetrical digraphs. He showed that for these objects there are natural analogs of classical theoretical results on usual network flows, such as the flow decomposition, aug

Debajyoti Choudhury, Anindya Datta, Katri Huitu, Partha Konar

We emphasise that charged slepton pairs produced via vector-boson fusion along with two high-mass, high-$p_T$ forward/backward jets (in two opposite hemispheres) can have a higher production cross-section for heavy slepton masses than that from conventional Drell-Yan production at a hadronic collider like the LHC. We analyse the signal and leading background

N. Ya. Ivanov

We analyze the perturbative and parametric stability of the QCD predictions for the azimuthal asymmetries in heavy quark leptoproduction. At leading order, the $\cos ϕ$ asymmetry vanishes whereas the $\cos 2ϕ$ one is of leading twist and predicted to be about 15% at energies sufficiently above the production threshold. We calculate the NLO soft-gluon correct

Arihiro Mizutani, Masashi Chiba, Tsuyoshi Sakamoto

We present the kinematic properties of a tidally disrupted dwarf galaxy in the Milky Way, based on the hypothesis that its central part once contained the most massive Galactic globular cluster, omega Cen. Dynamical evolution of a self-gravitating progenitor galaxy that follows the present-day and likely past orbits of omega Cen is calculated numerically and

Dexin Zhong, Daniel ben-Avraham, Miguel A. Munoz

A two-offspring branching annihilating random walk model, with finite reaction rates, is studied in one-dimension. The model exhibits a transition from an active to an absorbing phase, expected to belong to the $DP2$ universality class embracing systems that possess two symmetric absorbing states, which in one-dimensional systems, is in many cases equivalent

Takeshi Fukuyama, Tatsuru Kikuchi, Nobuchika Okada

In the recently proposed minimal supersymmetric SO(10) model, the neutrino Dirac Yukawa coupling matrix, together with all the other fermion mass matrices, is completely determined once free parameters in the model are appropriately fixed so as to accommodate the recent neutrino oscillation data. Using this unambiguous neutrino Dirac Yukawa couplings, we cal

H. Nagahiro, D. Jido, S. Hirenzaki

The properties of eta-nucleus interaction and their experimental consequences are investigated with eta-nucleus optical potentials obtained by postulating the N*(1535) dominance for eta-N system. The N*(1535) properties in nuclear medium are evaluated by two kinds of chiral effective models based on distinct pictures of N*(1535). We find that these two model

Wung-Hong Huang

The mechanism of recombination of intersecting D-branes is investigated within the framework of effective tachyon field theory. We regard the branes as the kink-type tachyon condensed states and use the effective two-tachyon Lagrangian to study the off-diagonal fluctuations therein. It is seen that there is a tachyonic mode in the off-diagonal fluctuations,

Nobuyoshi Ohta

We study aspects of the accelerating cosmologies obtained from the compactification of vacuum solution and S2-branes of superstring/M theories. Parameter dependence of the resulting expansion of our universe and internal space is examined for all cases. We find that accelerating expansions are obtained also from spherical internal spaces, albeit the solution

R. Enomoto, L. T. Ksenofontov, H. Katagiri, K. Tsuchiya

We searched for TeV gamma-rays from the remnant of SN 1987A around 5400 days after the supernova. The observations were carried out in 2001, from November 16 to December 11, using the CANGAROO-II Imaging Atmospheric Cherenkov Telescope. In total, 708 minutes of ON- and 1019 minutes of OFF-source data were obtained under good conditions. The detection thresho

Shan-Gui Zhou, Jie Meng, P. Ring

We discuss spin and pseudo-spin symmetry in the spectrum of single nucleons and single anti-nucleons in a nucleus. As an example we use relativistic mean field theory to investigate single anti-nucleon spectra. We find a very well developed spin symmetry in single anti-neutron and single anti-proton spectra. The dominant components of the wave functions of t

Julie D. Blum

Boundary states that preserve supersymmetry are constructed for fractional D-strings with travelling waves on a ${\bf C}^3/ {{\bf Z}_2\times {\bf Z}_2}$ orbifold. The gravitational radiation emitted between two D-strings with antiparallel travelling waves is calculated.