December 2003 arXiv papers — page 5

Yu. Kagan, L. A. Maksimov

The general system is given of nonlinear equations describing dissipationless evolution of the oscillating Bose-condensate. The relaxation of transverse oscillations of the condensate in a trap of the cylindric symmetry is considered. The evolution occurs due to parametric resonance coupling the transverse mode with the longitudinal ones. The nonlinear resca

A. V. Nikulov

Five years ago the talk "The vortex lattice melting theory as example of science fiction" cond-mat/9811051 was presented. Nevertheless this theory predominates up to now and very many people devote oneself to it. It is explained in the present paper why the only first order phase transition observed on the way from the Abrikosov state in the normal s

John P. Robinson, Malcolm P. Kennett, Nigel R. Cooper, Vladimir I. Fal'ko

We study the geometrical commensurability oscillations imposed onto the resistivity of 2D electrons in a perpendicular magnetic field by a propagating surface acoustic wave (SAW). We show that, for $ω<ω_{c}$, this effect is composed of an anisotropic dynamical classical contribution increasing the resistivity and the non-equilibrium quantum contribution isot

V. V. Khovailo, T. Abe, V. V. Koledov, M. Matsumoto

Differential scanning calorimetry (DSC) and magnetic measurements were performed to study the influence of ferromagnetic 3-d transition elements Fe and Co on structural and magnetic properties of ferromagnetic shape memory alloys Ni2MnGa. Addition of Fe or Co on the Ni sites decreases the temperature of martensitic phase transition Tm, whereas addition of Co

V. N. Glazkov, A. I. Smirnov, H. Tanaka, A. Oosawa

Three kinds of magnetic resonance signals were detected in crystals of the spin-gap magnet TlCuCl_3. First, we have observed the microwave absorption due to the excitation of the transitions between the singlet ground state and the excited triplet states. This mode has the linear frequency-field dependence corresponding to the previously known value of the z

Thomas Buchert, Mauro Carfora

We discuss the relation between `bare&#39; cosmological parameters as the true spatial average characteristics that determine the cosmological model, and the parameters interpreted by observers with a `Friedmannian bias&#39;, i.e., within a homogeneous space geometry. We may say that the latter are `dressed&#39; by the smoothed-out geometrical inhomogeneitie

Yuko Motizuki, Shiomi Kumagai

We investigate radioactivity from the decay sequence of 44Ti in a young supernova remnant SN 1987A. We perform Monte-Carlo simulations of degradation of the nuclear lines to explain a late-time bolometric luminosity which is estimated from optical and near-infrared observation at 3600 days after the explosion. Assuming the distance to LMC in between 45.5 and

Yuko Motizuki, Hideki Madokoro, Tetsuya Shimizu

We demonstrate the importance of anisotropic neutrino radiation in the mechanism of core-collapse supernova explosions. Through a new parameter study with a fixed radiation field of neutrinos, we show that global anisotropy of the neutrino radiation is the most effective mechanism of increasing the explosion energy when the total neutrino luminosity is given

Leonard Parker, Daniel A. T. Vanzella

We investigate the possibility that the late acceleration observed in the rate of expansion of the universe is due to vacuum quantum effects arising in curved spacetime. The theoretical basis of the vacuum cold dark matter (VCDM), or vacuum metamorphosis, cosmological model of Parker and Raval is revisited and improved. We show, by means of a manifestly nonp

S. Armstrong, B. Mellado, Sau Lan Wu

Recent strong experimental evidence of a narrow exotic S = +1 baryon resonance, $Θ^+$, suggests the existence of other exotic baryons. We discuss the prospects of confirming earlier experimental evidence of $Θ^+$ and the observation of additional hypothetical exotic baryons in $e^+e^-$ annihilations and $γγ$ collisions at LEP and B Factories.

Qing-Hong Cao, Shrihari Gopalakrishna, C. -P. Yuan

We consider right-handed neutrinos propagating in $δ$ (large) extra dimensions, whose only coupling to Standard Model fields is the Yukawa coupling to the left-handed neutrino and the Higgs boson. These theories are attractive as they can explain the smallness of the neutrino mass, as has already been shown. We show that if $δ$ is bigger than two, there are

Valery Weber, Anders Niklasson, Matt Challacombe

A linear scaling method for calculation of the static {\em ab inito} response within self-consistent field theory is developed and applied to calculation of the static electric polarizability. The method is based on density matrix perturbation theory [Niklasson and Challacombe, cond-mat/0311591], obtaining response functions directly via a perturbative appro

Igor Nikolaev

It is shown, that the mapping class group of a surface of the genus g > 1 admits a faithful representation into the matrix group GL (6g-6, Z). The proof is based on a categorical correspondence between the Riemann surfaces and the so-called toric AF-algebras.

Gregory Ryskin

The timeline of the Earth&#39;s history reveals quasi-periodicity of the geological record over the last 542 Myr, on timescales close, in the order of magnitude, to 1 Myr. What is the origin of this quasi-periodicity? What is the nature of the global events that define the boundaries of the geological time scale? I propose that a single mechanism is responsi

Robert Brandenberger, Pei-Ming Ho, Hsien-chung Kao

We motivate inflationary scenarios with many scalar fields, and give a complete formulation of adiabatic and entropy perturbations. We find that if the potential is very flat, or if the theory has a SO(N) symmetry, the calculation of the fluctuation spectrum can be carried out in terms of merely two variables without any further assumption. We do not have to

N. L. Wang, P. Zheng, D. Wu, Y. C. Ma

We present measurements of the optical spectra on Na$_{0.7}$CoO$_2$ single crystals. The optical conductivity shows two broad interband transition peaks at 1.6 eV and 3.2 eV, and a weak midinfrared peak at 0.4 eV. The intraband response of conducting carriers is different from that of a simple Drude metal. A peak at low but finite frequency is observed, whic

Massimo Giovannini

Cosmology, high-energy physics and astrophysics are converging on the study of large-scale magnetic fields. While the experimental evidence for the existence of large-scale magnetization in galaxies, clusters and superclusters is rather compelling, the origin of the phenomenon remains puzzling especially in light of the most recent observations. The purpose

Nils Bruin, E. Victor Flynn, Josep Gonzalez, Victor Rotger

It is conjectured that there exist finitely many isomorphism classes of simple endomorphism algebras of abelian varieties of GL_2-type over \Q of bounded dimension. We explore this conjecture when particularized to quaternion endomorphism algebras of abelian surfaces by giving a moduli interpretation which translates the question into the diophantine arithme

Y. Tezuka, K. Kanai, H. Ishii, S. Shin

Resonant inverse photoemission spectra of Ni metal have been obtained across the Ni 3$p$ absorption edge. The intensity of Ni 3$d$ band just above Fermi edge shows asymmetric Fano-like resonance. Satellite structures are found at about 2.5 and 4.2 eV above Fermi edge, which show resonant enhancement at the absorption edge. The satellite structures are due to

D. V. Posvyanskii

Effect of long range charge density oscillations on capacity of tunnel structure is studied within random phase approximation (RPA). Using this approximation we obtain expressions for the short and the long distance behavior of the self-consistent screened potential. We demonstrate that long range density oscillation, commonly referred to as Friedel oscillat

H. Onodera, T. Tohyama, S. Maekawa

We investigate the temperature dependence of optical absorption spectra of one-dimensional (1D) and two-dimensional (2D) Mott insulators by using an effective model in the strong-coupling limit of a half-filed Hubbard model. In the numerically exact diagonalization calculations on finite-size clusters, we find that in 1D the energy position of the absorption

Takuji Nomura, Jun-ichi Igarashi

We provide a semiquantitative explanation of a recent experiment on the resonant inelastic x-ray scattering (RIXS) in insulating cuprate La2CuO4 (Y.J. Kim et al., Phys. Rev. Lett. 89, 177003 (2002).). We show theoretically that there are three characteristic peaks in RIXS spectra, two of which are attributed to the charge transfer excitation and are reasonab

Robert Mann, Cristian Stelea

We construct new solutions of the vacuum Einstein field equations with cosmological constant. These solutions describe spacetimes with non-trivial topology that are asymptotically dS, AdS or flat. For a negative cosmological constant these solutions are NUT charged generalizations of the topological black hole solutions in higher dimensions. We also point ou

Yoshimichi Ueda

Reduced HNN extensions of von Neumann algebras (as well as $C^*$-algebras) will be introduced, and their modular theory, factoriality and ultraproducts will be discussed. In several concrete settings, detailed analysis on them will be also carried out.

Philip Walther, Jian-Wei Pan, Markus Aspelmeyer, Rupert Ursin

Superposition is one of the most distinct features of quantum theory and has been demonstrated in numerous realizations of Young&#39;s classical double-slit interference experiment and its analogues. However, quantum entanglement - a significant coherent superposition in multiparticle systems - yields phenomena that are much richer and more interesting than

J. Wang, Yifu Zhu, K. J. Jiang, M. S. Zhan

In a three-level atomic system coupled by two equal-amplitude laser fields with a frequency separation 2$δ$, a weak probe field exhibits a multiple-peaked absorption spectrum with a constant peak separation $δ$. The corresponding probe dispersion exhibits steep normal dispersion near the minimum absorption between the multiple absorption peaks, which leads t

A. Gilchrist, Kae Nemoto, W. J. Munro, T. C. Ralph

We outline a toolbox comprised of passive optical elements, single photon detection and superpositions of coherent states (Schrodinger cat states). Such a toolbox is a powerful collection of primitives for quantum information processing tasks. We illustrate its use by outlining a proposal for universal quantum computation. We utilize this toolbox for quantum

Debabrata Goswami

Quantum computing exploits the quantum-mechanical nature of matter to exist in multiple possible states simultaneously. This new approach promises to revolutionize the present form of computing. As an approach to quantum computing, we discuss ultrafast laser pulse shaping, in particular, the acousto-optic modulator based Fourier-Transform pulse-shaper, which

Zhanjun Lu, Ying Lu, Shuxia Song, Zhai Yu

To test whether X-chromosome has unique genomic characteristics, X-chromosome and 22 autosomes were compared for RNA binding density. Nucleotide sequences on the chromosomes were divided into 50kb per segment that was recoded as a set of frequency values of 7-nucleotide (7nt) strings using all possible 7nt strings (47=16384). 120 genes highly expressed in to

L. Chen, P. G. Debenedetti, C. W. Gear, I. G. Kevrekidis

In the context of the recently developed &#34;equation-free&#34; approach to the computer-assisted analysis of complex systems, we illustrate the computation of coarsely self-similar solutions. Dynamic renormalization and fixed point algorithms for the macroscopic density dynamics are applied to the results of short bursts of appropriately initialized molecu

Wolfgang Rolke, Angel Lopez

We describe a statistical hypothesis test for the presence of a signal. The test allows the researcher to fix the signal location and/or width a priori, or perform a search to find the signal region that maximizes the signal. The background rate and/or distribution can be known or might be estimated from the data. Cuts can be used to bring out the signal.

Jens Eggers

A prototypical problem in the study of wetting phenomena is that of a solid plunging into or being withdrawn from a liquid bath. In the latter, de-wetting case, a critical speed exists above which a stationary contact line is no longer sustainable and a liquid film is being deposited on the solid. Demonstrating this behavior to be a hydrodynamic instability

Keang-Po Ho

The statistical properties of nonlinear phase noise, often called the Gordon-Mollenauer effect, is studied analytically when the number of fiber spans is very large. The joint characteristic functions of the nonlinear phase noise with electric field, received intensity, and the phase of amplifier noise are all derived analytically. Based on the joint charact

D. J. Rowe

A computationally tractable version of the Bohr-Mottelson collective model is presented which makes it possible to diagonalize realistic collective models and obtain convergent results in relatively small appropriately chosen subspaces of the collective model Hilbert space. Special features of the proposed model is that it makes use of the beta wave function

A. Drago, A. Lavagno, P. Quarati

Following the basic prescriptions of the Tsallis&#39; nonextensive thermodynamics, we study the relativistic nonextensive thermodynamics and the equation of state for a perfect gas at the equilibrium. The obtained results are used to study the relativistic nuclear equation of state in the hadronic and in the quark-gluon plasma phase. We show that small devia

S. Fujii, R. Okamoto, K. Suzuki

Shell structures in the N\simeq Z nucleus ^{17}O and the neutron-rich oxygen isotopes ^{23}O and ^{25}O are microscopically described by calculating single-particle energies with modern nucleon-nucleon interactions within the framework of the unitary-model-operator approach. It is found that the effect of three-body cluster terms on the single-particle energ

F. Ferro, A. Lavagno, P. Quarati

We study the dependence of the CNO nuclear reaction rates on temperature, in the range of $10^7÷10^8$ K, the typical range of temperature evolution from a Sun-like star towards a white dwarf. We show that the temperature dependence of the CNO nuclear reaction rates is strongly affected by the presence of non-extensive statistical effects in the dense stellar

F. Ferro, A. Lavagno, P. Quarati

We study two different physical scenarios of thermonuclear reactions in stellar plasmas proceeding through a narrow resonance at low energy or through the low energy wing of a wide resonance at high energy. Correspondingly, we derive two approximate analytical formulae in order to calculate thermonuclear resonant reaction rates inside very coupled and non id

Xiaonan Wang, Ying Lu, Minxi Jiang, Qi Ouyang

Trapping and un-trapping of spiral tips in a two-dimensional homogeneous excitable medium with local small-world connections is studied by numerical simulation. In a homogeneous medium which can be simulated with a lattice of regular neighborhood connections, the spiral wave is in the meandering regime. When changing the topology of a small region from regul

M. Klein, E. Korotyaev, A. Pokrovski

Consider the operator $ T=-{d^2dx^2}+x^2+q(x)$ in $L^2(\mathbb{R})$, where real functions $q$, $q&#39;$ and $\int_0^xq(s)ds$ are bounded. In particular, $q$ is periodic or almost periodic. The spectrum of $T$ is purely discrete and consists of the simple eigenvalues $\{μ_n\}_{n=0}^\infty$, $μ_n<μ_{n+1}$. We determine their asymptotics $μ_n = (2n+1) + (2π)^{-

Ali Mostafazadeh

We study the regular representation $ρ_ζ$ of the single-fermion algebra ${\cal A}_ζ$, i.e., $c^2=c^{+2}=0$, $cc^++c^+c=ζ~1$, for $ζ\in [0,1]$. We show that $ρ_0$ is a four-dimensional nonunitary representation of ${\cal A}_0$ which is faithfully irreducible (it does not admit a proper faithful subrepresentation). Moreover, $ρ_0$ is the minimal faithfully irr

Gianluca Panati, Herbert Spohn, Stefan Teufel

We study approximate solutions to the Schrödinger equation $i\epsi\partialψ_t(x)/\partial t = H(x,-i\epsi\nabla_x) ψ_t(x)$ with the Hamiltonian given as the Weyl quantization of the symbol $H(q,p)$ taking values in the space of bounded operators on the Hilbert space $\Hi_{\rm f}$ of fast ``internal&#39;&#39; degrees of freedom. By assumption $H(q,p)$ has an

Pavel Etingof

Recently, motivated by supersymmetric gauge theory, Cachazo, Douglas, Seiberg, and Witten proposed a conjecture about finite dimensional simple Lie algebras, and checked it in the classical cases. Later V. Kac and the author proposed a uniform approach to this conjecture, based on the theory of abelian ideals in the Borel subalgebra; this allowed them to che

N. J. A. Sloane

This article gives a brief introduction to the On-Line Encyclopedia of Integer Sequences (or OEIS). The OEIS is a database of nearly 90,000 sequences of integers, arranged lexicographically. The entry for a sequence lists the initial terms (50 to 100, if available), a description, formulae, programs to generate the sequence, references, links to relevant web

Aristides Kontogeorgis

We give an alternative approach to the computation of the dimension of the tangent space of the deformation space of curves with automorphisms. A homological version of the local-global principle similar to the one of J.Bertin, A. Mézard is proved, and a computation in the case of ordinary curves is obtained, by application of the results of S. Nakajima for

Chaz Schlindwein

The following is consistent: There is a stationary set S such that every Aronszajn tree is S-*-special and there is an Aronszajn tree T such that for every unbounded E we have T is not E-special. This answers a question of Shelah (Proper and Improper Forcing, IX.4.9(5).

A. Gorodentscev, S. Kuleshov, A. Rudakov

We propose the notion of stability on a triangulated category that is a generalization of the T.Bridgeland&#39;s stability data. We establish connections between stabilities and t-structures on a category and as application we get the classification of bounded t-structures on the bounded derived category of coherent sheaves on a line.

Ales Vavpetic, Antonio Viruel

We study the mod p cohomology of the classifying space of the projective unitary group PU(p). We first proof that old conjectures due to J.F. Adams, and Kono and Yagita about the structure of the mod p cohomology of classifying space of connected compact Lie groups held in the case of PU(p). Finally, we proof that the classifying space of the projective unit

S. Gustafson, I. M. Sigal

We study solutions of Ginzburg-Landau-type evolution equations (both dissipative and Hamiltonian) with initial data representing collections of widely-spaced vortices. We show that for long times, the solutions continue to describe collections of vortices, and we identify (to leading order in the vortex separation) the dynamical system describing the motion

L. Alonso, P. Chassaing, F. Gillet, S. Janson

We provide a probabilistic analysis of the output of Quicksort when comparisons can err.

John G. Ratcliffe, Steven T. Tschantz

In this paper, Problem 4.17 on R. Kirby&#39;s problem list is solved by constructing infinitely many aspherical 4-manifolds that are homology 4-spheres

Seok-Jin Kang, Hyeonmi Lee

Using combinatorics of Young walls, we give a new realization of arbitrary level irreducible highest weight crystals $\mathcal{B}(λ)$ for quantum affine algebras of type $A_n^{(1)}$, $B_n^{(1)}$, $C_n^{(1)}$, $A_{2n-1}^{(2)}$, $A_{2n}^{(2)}$, and $D_{n+1}^{(2)}$. The irreducible highest weight crystals are realized as the affine crystals consisting of reduce

Anders Skovsted Buch

We prove K-theoretic generalizations of the component formulas of Knutson, Miller, and Shimozono, and deduce that K-theoretic quiver coefficients have alternating signs. We also prove new variants of the factor sequences conjecture, and a conjecture of Knutson, Miller, and Shimozono stating that the double ratio formula agrees with the original quiver formul

Yuji Hara

Affine analogue of Jack&#39;s polynomials introduced by Etingof and Kirillov Jr. is studied for the case of \hat{sl}_2. Using the Wakimoto representation, we give an integral formula of elliptic Selberg type for the affine Jack&#39;s polynomials. From this integral formula, the action of SL_2(Z) on the space of the affine Jack&#39;s polynomials is computed.

Howard Kleiman

This version is similar to math.CO/0210113. We&#39;ve changed Conjectures 1.1 and 1.2 so that they cover arbitrary graphs(digraphs). Let G be an arbitrary graph(digraph). Then - in polynomial time - either an algorithm obtains a hamilton circuit(cycle)or else the algorithm points to at least one vertex that cannot belong to any hamilton circuit(cycle) of G.

Aristides Kontogeorgis

This paper has been withdrawn by the author. The main result is wrong, as M.Matignon and C. Lehr provided a counterexample to it.

F. P. Boca, C. Cobeli, A. Zaharescu

We prove some asymptotic results on the distribution of h-tuples of consecutive Farey fractions of order Q with odd denominators as $Q\to \infty$.

John Terilla

The moduli space of generalized deformations of a Calabi-Yau hypersurface is computed in terms of the Jacobian ring of the defining polynomial. The fibers of the tangent bundle to this moduli space carry algebra structures, which are identified using subalgebras of a deformed Jacobian ring.

G. Gabadadze, M. Shifman

Large-distance modification of gravity may be the mechanism for solving the cosmological constant problem. A simple model of the large-distance modification -- four-dimensional (4D) gravity with the hard mass term-- is problematic from the theoretical standpoint. Here we discuss a different model, the brane-induced gravity, that effectively introduces a soft

Ivo Sachs

We review different applications of quasinormal modes to black hole physics, string theory and thermalisation in quantum field theory. In particular, we describe the the relation between quasi normal modes of AdS black holes and the time scale for thermalisation in strongly coupled, large $N$ conformal field theory. We also discuss the problem of unitarity w

C. I. Lazaroiu

I propose a general form for the boundary coupling of B-type topological Landau-Ginzburg models. In particular, I show that the relevant background in the open string sector is a (generally non-Abelian) superconnection of type (0,1) living in a complex superbundle defined on the target space, which I allow to be a non-compact Calabi-Yau manifold. This extend

Vincent Bouchard, Harald Skarke

Candelas and Font introduced the notion of a `top&#39; as half of a three dimensional reflexive polytope and noticed that Dynkin diagrams of enhanced gauge groups in string theory can be read off from them. We classify all tops satisfying a generalized definition as a lattice polytope with one facet containing the origin and the other facets at distance one

Lubos Motl, Andrew Neitzke

We give a new derivation of the quasinormal frequencies of Schwarzschild black holes in d>=4 and Reissner-Nordstrom black holes in d=4, in the limit of infinite damping. For Schwarzschild in d>=4 we find that the asymptotic real part is T_Hawking.log(3) for scalar perturbations and for some gravitational perturbations; this confirms a result previously obtai

Amer Iqbal

We study BPS states in type IIA string compactification on a local Calabi-Yau 3-fold which are related to the BPS states of the E-string. Using Picard-Lefshetz transformations of the 3-cycles on the mirror manifold we determine automorphisms of the K-theory of the compact divisor of the Calabi-Yau which maps certain D-brane configurations to a bound state of

C. P. Burgess N. S. Dzhalilov, M. Maltoni, T. I. Rashba, V. B. Semikoz

This review has two parts. The first part summarizes the current observational constraints on fluctuations in the solar medium deep within the solar Radiative Zone, and shows how the KamLAND and SNO-salt data combine to make the experimental determination of the neutrino oscillation parameters largely insensitive to prior assumptions about the nature of thes

Oleg V. Pavlovsky

Finite-energy topological spherically symmetrical solutions of Chiral Born-Infeld Theory are studied. Properties of these solution are obtained, and a possible physical interpretation is also given. We compute static properties of baryons (mass,main radius, magnetic main radius, axial coupling constant) whose solutions can be interpreted as the baryons of QC

Samim Erhan, Victor T. Kim, Peter E. Schlein

Contrary to common perceptions about systems produced in Single-Pomeron-Exchange (SPE) pp interactions, the hard diffractive process discovered at the CERN SPS-Collider leads to dominant central production of Higgs bosons at the LHC. The rate for SPE production of Higgs bosons is calculated to be 7-9 % of the total inclusive Higgs rate. In addition, an SPE m

Maria Krawczyk

Recent results obtained within ECFA/DESY and ECFA Study by the Higgs and gamma gamma /e gamma physics working groups are presented.

Maria Krawczyk

A short overview of basics aspects of hadronic interaction of the photon is presented.

M. Lorente

Using the method of finite differences a scheme is proposed to solve exactly the Klein-Gordon and Dirac free field equations, in a (1+1)-dimensional lattice. The hamiltonian of the Dirac field is translational invariant, hermitian, avoids fermion doubling, and, for the massless case, preserves global chiral symmetry. Coupling the fermion field to the electro

Sugumi Kanno, Jiro Soda

In the Randall-Sundrum two-brane model (RS1), a Kerr black hole on the brane can be naturally identified with a section of rotating black string. To estimate Kaluza-Klein (KK) corrections on gravitational waves emitted by perturbed rotating black strings, we give the effective Teukolsky equation on the brane which is separable equation and hence numerically

Jiro Soda, Sugumi Kanno

Evaluating Kaluza-Klein (KK) corrections is indispensable to test the braneworld scenario. In this report, we propose a novel symmetry approach to an effective 4-dimensional action with KK corrections for the Randall-Sundrum two-brane system.

C. J. Isham

A new approach is suggested to the problem of quantising causal sets, or topologies, or other such models for space-time (or space). The starting point is the observation that entities of this type can be regarded as objects in a category whose arrows are structure-preserving maps. This motivates investigating the general problem of quantising a system whose

Lubos Motl

Recently it has been proposed that a strange logarithmic expression for the so-called Barbero-Immirzi parameter, which is one of the ingredients that are necessary for Loop Quantum Gravity (LQG) to predict the correct black hole entropy, is not another sign of the inconsistency of this approach to quantization of General Relativity, but is rather a meaningfu

José Júlio Alferes, Luís Moniz Pereira, Terrance Swift

Abductive logic programming offers a formalism to declaratively express and solve problems in areas such as diagnosis, planning, belief revision and hypothetical reasoning. Tabled logic programming offers a computational mechanism that provides a level of declarativity superior to that of Prolog, and which has supported successful applications in fields such

Christian A. Duncan, David Eppstein, Stephen G. Kobourov

We prove that the geometric thickness of graphs whose maximum degree is no more than four is two. All of our algorithms run in O(n) time, where n is the number of vertices in the graph. In our proofs, we present an embedding algorithm for graphs with maximum degree three that uses an n x n grid and a more complex algorithm for embedding a graph with maximum

Alexander Serebrenik, Danny De Schreye

The term {\em meta-programming} refers to the ability of writing programs that have other programs as data and exploit their semantics. The aim of this paper is presenting a methodology allowing us to perform a correct termination analysis for a broad class of practical meta-interpreters, including negation and performing different tasks during the execution

S. Syed, M. J. Manfra, Y. J. Wang, R. J. Molnar

We present data on mobility lifetime, $τ_t$, quantum lifetime, $τ_q$, and cyclotron resonance lifetime, $τ_{CR}$, of a sequence of high-mobility two-dimensional electron gases in the AlGaN/GaN system, covering a density range of $\sim1-4.5\times10^{12}$cm$^{-2}$. We observe a large discrepancy between $τ_q$ and $τ_{CR}$ ($τ_q\simτ_{CR}$/6) and explain it as

Marina Bastea

A comment on ``Metallization of Fluid Nitrogen and the Mott Transition in Highly Compressed Low-Z Fluids&#39;&#39; by Chau et al, Phys. Rev. Lett. 90, 245501 (2003).

Alain Delgado, Augusto Gonzalez, D. J. Lockwood

A consistent semiquantitative theoretical analysis of electronic Raman scattering from many-electron quantum dots under resonance excitation conditions has been performed. The theory is based on random-phase-approximation-like wave functions, with the Coulomb interactions treated exactly, and hole valence-band mixing accounted for within the Kohn-Luttinger H

A. Yu. Smirnov

We study dissipative dynamics and a magnetic response of two coupled flux qubits interacting with a high quality tank in the framework of the impedance measurement technique (IMT). It is shown that the observation of the difference between a sum of IMT signals from separated qubits and the signal from the system when both qubits are in the degeneracy point (

Augusto Gonzalez

The anharmonicity of a magnetic atomic trap at long distances from its center (forty times the radius of the first atomic orbit along the elongated axis, i.e. hundreds of microns) is shown to increase up to 45 % the temperature for Bose-Einstein condensation. This effect is perhaps small in the traditional traps, but should certainly be taken into account in

K. S. Novoselov, A. K. Geim, S. V. Dubonos, E. W. Hill

Movements of individual domain walls in a ferromagnetic garnet were studied with angstrom resolution. The measurements reveal that domain walls can be locked between adjacent crystallographic planes and propagate by distinct steps matching the lattice periodicity. Domain walls are found to be weakly mobile within valleys of the atomic washboard but become un

Boris M. Shipilevsky

We present the growth dynamics of an island of particles $A$ injected from a localized $A$-source into the sea of particles $B$ and dying in the course of diffusion-controlled annihilation $A+B\to 0$. We show that in the 1d case the island unlimitedly grows at any source strength $Λ$, and the dynamics of its growth {\it does not depend} asymptotically on the

J. F. Fernandez, J. J. Alonso

We model magnetization processes that take place through tunneling in crystals of single-molecule magnets, such as Mn_12 and Fe_8. These processes take place when a field H is applied after quenching to very low temperatures. Magnetic dipolar interactions and spin flipping rules are essential ingredients of the model. The results obtained follow from Monte C

I. Siddiqi, R. Vijay, F. Pierre, C. M. Wilson

We have constructed a new type of amplifier whose primary purpose is the readout of superconducting quantum bits. It is based on the transition of an RF-driven Josephson junction between two distinct oscillation states near a dynamical bifurcation point. The main advantages of this new amplifier are speed, high-sensitivity, low back-action, and the absence o

Zahirul Islam, X. Liu, S. K. Sinha, J. C. Lang

Using high-energy diffraction we show that a 4-unit-cell superstructure, q0=(1/4,0,0), along the shorter Cu-Cu bonds coexists with superconductivity in optimally doped YBCO. A complex set of anisotropic atomic displacements on neighboring CuO chain planes, BaO planes, and CuO2 planes, respectively, correlated over ~3-6 unit cells gives rise to diffuse superl

Cheng Chin, Vladan Vuletic, Andrew J. Kerman, Steven Chu

We have observed and located more than 60 magnetic field-induced Feshbach resonances in ultracold collisions of ground-state $^{133}$Cs atoms. These resonances are associated with molecular states with up to four units of rotational angular momentum, and are detected through variations in the elastic, inelastic, and radiative collision cross sections. These

Falk Herwig

(abbreviated) The evolution of intermediate mass stars at very low metallicity during their final thermal pulse asymptotic giant branch phase is studied in detail. As representative examples models with initial masses of 4Msun and 5Msun with a metallicity of Z=0.0001 ([Fe/H] ~ -2.3) are discussed. The 1D stellar structure and evolution model includes time- a

Volodymyr Kryvdyk

The non-thermal emission in the magnetospheres of presupernova collapsing stars with initial dipole magnetic fields and a certain initial energy distribution of the charged particles in a magnetosphere is considered. The analysis of particle dynamics and its emission in the stellar magnetosphere under collapse show that the collapsing stars can be the powerf

Thijs van der Hulst, Renzo Sancisi

Studies of the HI in galaxies have clearly shown that subtle details of the HI distribution and kinematics often harbour key information for understanding the structure and evolution of galaxies. Evidence for the accretion of material has grown over the past many years and clear signatures can be found in HI observations of galaxies. We have obtained new det

M. Boettcher

Absorption and reprocessing of Gamma-ray burst radiation in the environment of cosmological GRBs can be used as a powerful probe of the elusive nature of their progenitors. Although it is widely accepted that long-duration GRBs are associated with the deaths of massive stars, at least two fundamentally different scenarios concerning the final collapse are cu

Alexei Baskin, Ari Laor

The origin of the luminosity dependence of the strength of broad and narrow emission lines in AGN (i.e. the Baldwin effect) is not firmly established yet. We explore this question using the Boroson & Green sample of the 87 z<=0.5 PG quasars. UV spectra of the C IV region with a sufficient S/N are available for 81 of the objects. We use these spectra to explo

Ari Laor

The bimodality of the AGN radio loudness distribution, and the relation of radio loudness and black hole mass were recently disputed. A closer look at the existing data suggests possible resolutions of these disputes, as further described below.

F. Szalma, Hailu Gebremariam, T. L. Einstein

We analyze in detail the fluctuations and correlations of the (spatial) Fourier modes of nano-scale single-layer islands on (111) fcc crystal surfaces. We analytically show that the Fourier modes of the fluctuations couple due to the anisotropy of the crystal, changing the power spectrum of the fluctuations, and that the actual eigenmodes of the fluctuations

Jun Zhang, Jiri Vala, Shankar Sastry, K. Birgitta Whaley

Optimal construction of quantum operations is a fundamental problem in the realization of quantum computation. We here introduce a newly discovered quantum gate, B, that can implement any arbitrary two-qubit quantum operation with minimal number of both two- and single-qubit gates. We show this by giving an analytic circuit that implements a generic nonlocal

S. Kondratyuk, K. Kubodera, F. Myhrer, O. Scholten

The Adler-Weisberger and Goldberger-Miyazawa-Oehme sum rules are calculated within a relativistic, unitary and crossing symmetric dynamical model for pion-nucleon scattering using two different methods: 1) by evaluating the scattering amplitude at the corresponding low-energy kinematics and 2) by evaluating the sum-rule integrals with the calculated total cr

J. E. Hirsch

An alternate set of equations to describe the electrodynamics of superconductors at a macroscopic level is proposed. These equations resemble equations originally proposed by the London brothers but later discarded by them. Unlike the conventional London equations the alternate equations are relativistically covariant, and they can be understood as arising f

Tetsuya Takaishi

The density of states method is applied for lattice QCD at a finite isospin density. The advantage of this method is that one can easily obtain results for various values of parameters (quark mass, coupling constant and the number of flavors). We compare results for the chiral condensate and the quark number density with those from the R-algorithm and find t

Alberto Guijosa, David A. Lowe

We stress that the dS/CFT correspondence should be formulated using unitary principal series representations of the de Sitter isometry group/conformal group, rather than highest-weight representations as originally proposed. These representations, however, are infinite-dimensional, and so do not account for the finite gravitational entropy of de Sitter space