February 2009 arXiv papers — page 38

Pak Yuen Chan, Nigel Goldenfeld, Jon Dantzig

We extend the phase field crystal model to accommodate exact atomic configurations and vacancies by requiring the order parameter to be non-negative. The resulting theory dictates the number of atoms and describes the motion of each of them. By solving the dynamical equation of the model, which is a partial differential equation, we are essentially performin

J. J. Bryant, H. M. Johnston, J. W. Broderick, R. W. Hunstead

We have compiled a sample of 234 ultra-steep-spectrum(USS)-selected radio sources in order to find high-redshift radio galaxies (HzRGs). The sample is in the southern sky at -40 deg < DEC < -30 deg which is the overlap region of the 408-MHz Revised Molonglo Reference Catalogue, 843-MHz Sydney University Molonglo Sky Survey (the MRCR--SUMSS sample) and the 14

H R Morton, N D A Ryder

We extend a mod 2 relation between the Kauffman and Homfly polynomials, first observed by Rudolph in 1987, to the general Kauffman and Homfly satellite invariants.

M. I. Mendelev, B. S. Bokstein

We employed a recently developed semi-empirical Zr potential to determine the diffusivities in the hcp and bcc Zr via molecular dynamics simulation. The point defect concentration was determined directly from MD simulation rather than from theoretical methods using T=0 calculations. We found that the diffusion proceeds via the interstitial mechanism in the h

P. N. Bibikov

Three-magnon problem for exactly rung-dimerized spin ladder is brought up separately at all total spin sectors. At first a special duality transformation of the $\rm Schr\ddot odinger$ equation is found within general outlook. Then the problem is treated within Coordinate Bethe Ansatze. A straightforward approach is developed to obtain pure scattering states

Jose A. Diaz-Garcia, Ramon Gutierrez-Jaimez

In this paper, we study some properties of multivariate gamma function and zonal polynomials.

László Lovász, Balázs Szegedy

In an earlier paper the authors proved that limits of convergent graph sequences can be described by various structures, including certain 2-variable real functions called graphons, random graph models satisfying certain consistency conditions, and normalized, multiplicative and reflection positive graph parameters. In this paper we show that each of these s

Min-xin Huang, Albrecht Klemm

We calculate the gravitational corrections to the effective action of N=2 SU(2) Seiberg-Witten theory with matter using modularity, the holomorphic anomaly equation and expected behavior at the boundaries of the moduli space. As in pure gauge theory we show that the gap condition at the dyon singularities completely fixes the gravitational corrections. We di

Brian McWilliams, Giovanni Montana

In this paper we propose a computationally efficient algorithm for on-line variable selection in multivariate regression problems involving high dimensional data streams. The algorithm recursively extracts all the latent factors of a partial least squares solution and selects the most important variables for each factor. This is achieved by means of only one

Bodo Lampe

The possible spatial transformation properties of tetrons are discussed.

A. Sargsyan, A. Papoyan, A. Sarkisyan, Yu. Malakyan

We report observation of a narrow (sub-natural) and high-contrast resonance of increased absorption (&#34;bright&#34; resonance) in Rb cell with Ne buffer gas under previously unexplored experimental conditions for coupling and probe radiation configuration. The coupling laser stabilized frequency is detuned by ~ 3 GHz from 5S1/2, Fg=3 --> 5P3/2, Fe=2,3,4 tr

T. -L. Horng, S. -C. Gou, T. -C. Lin, G. A. El

Formation of stationary 3D wave patterns generated by a small point-like impurity moving through a Bose-Einstein condensate with supersonic velocity is studied. Asymptotic formulae for a stationary far-field density distribution are obtained. Comparison with three-dimensional numerical simulations demonstrates that these formulae are accurate enough already

Peng Guo, Adam P. Szczepaniak

In the framework of Coulomb Gauge QCD we explore dynamical breaking of chiral symmetry and screening of the confinement potential at finite density. The screened potential is applied in study of charmonium dissociation.

S. Hubrig, M. Briquet, P. De Cat, M. Schoeller

We present the results of the continuation of our magnetic survey with FORS1 at the VLT of a sample of B-type stars consisting of confirmed or candidate beta Cephei stars and Slowly Pulsating B (hereafter SPB) stars, along with a small number of normal B-type stars. A weak mean longitudinal magnetic field of the order of a few hundred Gauss was detected in t

Mostafa Sharifzadeh, Yasuhiro Mitani, Tetsuro Esaki

Geometry of the rock joint is a governing factor for joint mechanical and hydraulic behavior. A new method of evaluating aperture distribution based on measurement of joint surfaces and three dimensional characteristics of each surface is developed. Artificial joint of granite surfaces are measured,processed, analyzed and three dimensional approaches are car

Mostafa Sharifzadeh, Ali Moradi Ghasr

The rock mechanical design of gas storage cavern in salt requires the analysis of the stability and the usability of the cavern over the planned operating time period. The design includes the build up of a rock mass model and a numerical model taking into account the geological situation, load condition, geometrical condition, and material parameters. In thi

Takeshi Go Tsuru, Masayoshi Nobukawa, Hiroshi Nakajima, Hironori Matsumoto

We present the Suzaku results on a new candidate of a supernova remnant (SNR) in the Sagittarius C region. We detected diffuse X-rays of an elliptical shape (G359.41-0.12) and a chimney-like structure (the Chimney), both of which were fitted with a thin thermal the model of kBT ~1 keV temperature. The absorption columns are same between these two structures,

E. Corrigan, C. Zambon

A simple, basic, argument is given, based solely on energy-momentum considerations to recover conditions under which a_r affine or conformal Toda field theories can support defects of integrable type. Associated triangle relations are solved to provide expressions for transmission matrices that generalize previously known examples calculated for the sine-Gor

Elvan Ceyhan

Proximity maps and regions are defined based on the relative allocation of points from two or more classes in an area of interest and are used to construct random graphs called proximity catch digraphs (PCDs) which have applications in various fields. The simplest of such maps is the spherical proximity map which maps a point from the class of interest to a

Armen G. Sergeev

In the first part of the paper we describe the complex geometry of the universal Teichmüller space $\mathcal T$, which may be realized as an open subset in the complex Banach space of holomorphic quadratic differentials in the unit disc. The quotient $\mathcal S$ of the diffeomorphism group of the circle modulo Möbius transformations may be treated as a smoo

Hirotada Kobayashi, Francois Le Gall, Harumichi Nishimura, Martin Roetteler

This paper considers a problem of quantum communication between parties that are connected through a network of quantum channels. The model in this paper assumes that there is no prior entanglement shared among any of the parties, but that classical communication is free. The task is to perfectly transfer an unknown quantum state from a source subsystem to a

Zhigang Wang, Wei Zhang, Ping Zhang

We study the de Haas--van Alphen (dHvA) oscillations in the magnetization of a two-dimensional electron gas (2DEG) under the influence of the edge states and/or the Rashba spin-orbit interaction (SOI). The boundaries of the systems lift partially the degeneracies of Landau levels (LL&#39;s) and the resulting edge states lead to the changes of both the center

A. N. Ogurtsov, O. N. Bliznjuk, N. Yu. Masalitina

The kinetics of the process of defect accumulation in rare-gas solids as a result of exciton self-trapping was studied using the selective vacuum ultraviolet photoluminescence method for monitoring of the crystal structure of the samples. The simple kinetic model of defect accumulation in rare-gas samples was applied to the fitting of the dose dependences of

Badam Singh Kushvah

Linearization of the Hamiltonian is being performed around the triangular equilibrium points in the generalized photogravitational Chermnykh&#39;s problem. The bigger primary is being considered as a source of radiation and small primary as an oblate spheroid. We have found the normal form of the second order part of the Hamiltonian. For this we have solved

N. Zarrabi, S. Ernst, M. G. Dueser, A. Golovina-Leiker

FoF1-ATP synthase is the enzyme that provides the &#39;chemical energy currency&#39; adenosine triphosphate, ATP, for living cells. The formation of ATP is accomplished by a stepwise internal rotation of subunits within the enzyme. Briefly, proton translocation through the membrane-bound Fo part of ATP synthase drives a 10-step rotary motion of the ring of c

D. V. Bugg

Statements concerning Extended Unitarity (EU) are clarified

Stan Gudder, Frederic Latremoliere

This article discusses the concept of Boolean spaces endowed with a Boolean valued inner product and their matrices. A natural inner product structure for the space of Boolean n-tuples is introduced. Stochastic boolean vectors and stochastic and unitary Boolean matrices are studied. A dimension theorem for orthonormal bases of a Boolean space is proven. We c

L. Prato, K. E. Lockhart, Christopher M. Johns-Krull, John T. Rayner

We present a study of the stellar and circumstellar properties of Class I sources using low-resolution (R~1000) near-infrared K- and L-band spectroscopy. We measure prominent spectral lines and features in 8 objects and use fits to standard star spectra to determine spectral types, visual extinctions, K-band excesses, and water ice optical depths. Four of th

Gian Franco Sacco

Since their advent, Parity Violating experiments have played a crucial role in testing the standard model (SM) of electroweak interactions. In recent years, these experiments have reached such a high degree of accuracy that they might test for physics beyond the SM. When making high precision measurements, a recurrent problem is how to properly include hadro

V. B. Naik, R. Mahendiran

We report magnetic and magnetoelectric studies on BiFeO3 and divalent cation (A) suvtitute Bi0.7A0.3FeO3 (A = Sr,Ba, and Sr0.5Ba0.5). It is shown that the rapid increase of magnetization at the Neel temperature (TN = 642 K) is suppressed in the co-doped compound A = Sr0.5Ba0.5. All the divalent subtituted compounds show enhanced magnetization and hysteresis

A. Rebello, R. Mahendiran

We report pulsed as well as direct current/voltage induced electroresistance in Bi0.8Sr0.2MnO3 at room temperature. It is shown that bi-level and multi-level resistivity switching can be induced by a sequence of pulses of varying pulse width at fixed voltage amplitude. Resistivity increases abruptly (= 55 % at 300 K) upon reducing pulse width from 100 ms to

Johannes Lischner, T. A. Arias

We present an accurate free-energy functional for liquid water written in terms of a set of effective potential fields in which fictitious noninteracting water molecules move. The functional contains an \emph{exact} expression of the entropy of noninteracting molecules and thus provides an ideal starting point for the inclusion of complex inter-molecular int

Salah A. Aly, Zhenning Kong, Emina Soljanin

We consider large-scale sensor networks with n nodes, out of which k are in possession, (e.g., have sensed or collected in some other way) k information packets. In the scenarios in which network nodes are vulnerable because of, for example, limited energy or a hostile environment, it is desirable to disseminate the acquired information throughout the networ

P. A. Khomyakov, G. Giovannetti, P. C. Rusu, G. Brocks

Measuring the transport of electrons through a graphene sheet necessarily involves contacting it with metal electrodes. We study the adsorption of graphene on metal substrates using first-principles calculations at the level of density functional theory. The bonding of graphene to Al, Ag, Cu, Au and Pt(111) surfaces is so weak that its unique &#34;ultrarelat

Zur Izhakian, Stuart Margolis

The main result of the paper proves that the monoid of all 2 x 2 tropical matrices satisfies a non-trivial semigroup identity, unlike the case of matrices over infinite fields. We exploit a strong connection between the monoid of all 2 x 2 tropical matrices and the bicyclic monoid to show that a variant of Adian&#39;s identity for the bicyclic monoid holds i

Tom Michoel, Jaideep Mulherkar, Bruno Nachtergaele

We demonstrate an implementation scheme for constructing quantum gates using unitary evolutions of the one-dimensional spin-J ferromagnetic XXZ chain. We present numerical results based on simulations of the chain using the time-dependent DMRG method and techniques from optimal control theory. Using only a few control parameters, we find that it is possible

Shaun V. Ault

The symmetric homology of a unital algebra $A$ over a commutative ground ring $k$ is defined using derived functors and the symmetric bar construction of Fiedorowicz. For a group ring $A = k[\Gamma]$, the symmetric homology is related to stable homotopy theory via $HS_*(k[\Gamma]) \cong H_*(\Omega\Omega^{\infty} S^{\infty}(B\Gamma); k)$. Two chain complexes

Andre Bueno, Ben Cox, Vyacheslav Futorny

In this paper we construct two free field realizations of the elliptic affine Lie algebra sl(2,R) + Ω_R/dR, where R=C[t,t^{-1},u|u^2=t^3 - 2b t^2 + t]. The first realization gives an analogue of Wakimoto&#39;s construction for Affine Kac-Moody algebras, but in the setting of the elliptic affine Lie algebra. The second realization gives new type of representa

CDF Collaboration, T. Aaltonen

We have observed the reactions p+pbar --> p+X+pbar, with X being a centrally produced J/psi, psi(2S) or chi_c0, and gamma+gamma --> mu+mu-, in proton- antiproton collisions at sqrt{s} = 1.96 TeV using the Run II Collider Detector at Fermilab. The event signature requires two oppositely charged muons, each with pseudorapidity |eta| < 0.6, with M(mumu) in [3.0

CDF Collaboration, T. Aaltonen

We performed a signature-based search for long-lived charged massive particles (CHAMPs) produced in 1.0 $\rm{fb}^{-1}$ of $\bar{p}p$ collisions at $\sqrt{s}=1.96$ TeV, collected with the CDF II detector using a high transverse-momentum ($p_T$) muon trigger. The search used time-of-flight to isolate slowly moving, high-$p_T$ particles. One event passed our se

Zilong Wang, Guang Gong

Following the approach developed by S. Gurevich and R. Hadani, an analytical formula of the canonical basis of the DFT is given for the case $N=p$ where $p$ is a prime number and $p\equiv 1$ (mod 4).

Benoit Blossier, Michele Della Morte, Georg von Hippel, Tereza Mendes

We discuss the generalized eigenvalue problem for computing energies and matrix elements in lattice gauge theory, including effective theories such as HQET. It is analyzed how the extracted effective energies and matrix elements converge when the time separations are made large. This suggests a particularly efficient application of the method for which we ca

Zurab Ratiani, Aditi Mitra

Results are presented for the nonequilibrium infinite-U Anderson model using a large-N approach, where $N$ is the degeneracy of the impurity level, and where nonequilibrium is established by coupling the level to two leads at two different chemical potentials so that there is current flow. A slave-boson representation combined with Keldysh functional integra

Sourav Chakraborty, Eldar Fischer, Arie Matsliah, Raphael Yuster

An edge-colored graph G is rainbow connected if any two vertices are connected by a path whose edges have distinct colors. The rainbow connectivity of a connected graph G, denoted rc(G), is the smallest number of colors that are needed in order to make G rainbow connected. In addition to being a natural combinatorial problem, the rainbow connectivity problem

S. Salem-Sugui, L. Ghivelder, A. D. Alvarenga, J. L. Pimentel Fr.

We report on isofield magnetization curves obtained as a function of temperature in two single crystals of $Ba_{1-x}K_xFe_2As_2$ with superconducting transition temperature $T_c$=28K and 32.7 K. Results obtained for fields above 20 kOe show a well defined rounding effect on the reversible region extending 1-3 K above $T_c(H)$ masking the transition. This rou

Alexandru Dimca, Stefan Papadima, Alexander I. Suciu

We elucidate the key role played by formality in the theory of characteristic and resonance varieties. We define relative characteristic and resonance varieties, V_k and R_k, related to twisted group cohomology with coefficients of arbitrary rank. We show that the germs at the origin of V_k and R_k are analytically isomorphic, if the group is 1-formal; in pa

A. P. Balachandran, M. Martone

The Moyal and Wick-Voros planes A^{M,V}_θ are *-isomorphic. On each of these planes the Poincaré group acts as a Hopf algebra symmetry if its coproducts are deformed by twist factors. We show that the *-isomorphism T: A^M_θ to A^V_θ does not also map the corresponding twists of the Poincaré group algebra. The quantum field theories on these planes with twist

K. Farakos, N. E. Mavromatos, P. Pasipoularides

We present a brief review of our recent work [1] on asymmetrically warped brane models, where the background metric is characterized by different time and space warp factors. In particular we examine the case of bulk photons and we show that the standard Lorentz invariant dispersion relation is corrected by nonlinear terms which lead to an Energy-dependent s

Jungsoo Kim

Let $M$ be a closed orientable 3-manifold with a genus two Heegaard splitting $(V_1, V_2; F)$ and a non-trivial JSJ-decomposition, where all components of the intersection of the JSJ-tori and $V_i$ are not $\partial$-parallel in $V_i$ for $i=1,2$. If $G$ is a finite group of orientation-preserving smooth actions on $M$ which preserves each handlebody of the

Mohammed Kabbour, Najib Mahdou

In this paper, we define and study a particular case of von Neumann regular notion called a weak von Neumann regular ring. It shown that the polynomial ring $R[x]$ is weak von Neumann regular if and only if $R$ has exactly two idempotent elements. We provide necessary and sufficient conditions for $ R=A\propto E $ to be a weak von Neumann ring. It is also sh

Christian Beck

The formalism of statistical mechanics can be generalized by starting from more general measures of information than the Shannon entropy and maximizing those subject to suitable constraints. We discuss some of the most important examples of information measures that are useful for the description of complex systems. Examples treated are the Renyi entropy, Ts

O. Khorunzhiy, J. -F. Marckert

Let D be a Dyck path chosen uniformly from the set of Dyck paths with 2n steps. We prove that the sequence of the exponential moments of the maximum of D normalized by the square root of n converges in the limit of infinite n, and therefore is bounded uniformly in n. This result justifies corresponding assumption used to prove certain estimates of high momen

Avinash Achar, Srivatsan Laxman, Raajay Viswanathan, P. S. Sastry

Frequent episode discovery is a popular framework for pattern discovery in event streams. An episode is a partially ordered set of nodes with each node associated with an event type. Efficient (and separate) algorithms exist for episode discovery when the associated partial order is total (serial episode) and trivial (parallel episode). In this paper, we pro

Kei-ichi Maeda, Yasunori Fujii

In the scalar-tensor theory of gravitation it seems nontrivial to establish if solutions of the cosmological equations in the presence of a cosmological constant behave as attractors independently of the initial values. We develop a general formulation in terms of two-dimensional phase space. We show that there are two kinds of fixed points, one of which is

Samuel Coskey

The isomorphism and quasi-isomorphism relations on the $p$-local torsion-free abelian groups of rank $n\geq3$ are incomparable with respect to Borel reducibility.

Yong Jiang, Jie Sheng, Jie Xiao

According to the Ringel-Green Theorem([G],[R1]), the generic composition algebra of the Hall algebra provides a realization of the positive part of the quantum group. Furthermore, its Drinfeld double can be identified with the whole quantum group([X],[XY]), in which the BGP-reflection functors coincide with Lusztig&#39;s symmetries. We first assert the eleme

E. S. Otabe, M. Kiuchi, S. Kawai, Y. Morita

The critical current densities of polycrystalline bulk SmFeAsO$_{1-x}$F$_x$ prepared by the powder-in-tube (PIT) method and by a conventional solid-state reaction were investigated using the remnant magnetic moment method and Campbell&#39;s method. Two types of shielding current, corresponding to global and local critical current densities $J_{\rm c}$ were o

Daniel Braun, John Martin

Quantum-enhanced measurements use highly non-classical quantum states in order to enhance the precision of the measurement of classical quantities, like the length of an optical cavity. The major goal is to beat the standard quantum limit (SQL), i.e. a precision of order $1/\sqrt{N}$, where $N$ is the number of quantum resources (e.g. the number of photons o

C. A. Vaquera-Araujo, M. Napsuciale

In this letter we study the reaction e^{+}e^{-}\toϕπ^0 ηwith the π^{0}ηsystem in an isoscalar s-wave configuration. We use a formalism recently developed for the study of e^{+}e^{-}\toϕππand e^{+}e^{-}\toϕK^{+}K^{-}. The obtained cross section is within the reach of present e^{+}e^{-} machines. Measuring this channel would test the absence of an isovector co

Guillermo P. Ortiz, Carlos A. Rinaldi, Norberto G. Boggio, Juan Vorobioff

Ion Mobility Spectrometry (IMS) is a well-known, sensitive and rapid technique to detect dangerous organic compounds. We propose a system in which a crown type discharge generates a ionic flow that is swept towards an array of collectors by a transverse electric field. The ions are separated as they enter the cell according to their mobility. Thus, the distr

Jalil Seifali Harsini, Farshad Lahouti

This paper presents a cross-layer approach for optimizing the delay performance of a multiuser diversity system with heterogeneous block-fading channels and a delay-sensitive bursty-traffic. We consider the downlink of a time-slotted multiuser system employing opportunistic scheduling with fair performance at the medium access (MAC) layer and adaptive modula

Tomas Everaert

Higher extensions and higher central extensions, which are of importance to non-abelian homological algebra, are studied, and some fundamental properties are proven. As an application, a direct proof of the invariance of the higher Hopf formulae is obtained.

V. R. Shaginyan, A. Z. Msezane, K. G. Popov, V. A. Stephanovich

A strong departure from Landau-Fermi liquid (LFL) behavior have been recently revealed in observed anomalies in both the magnetic susceptibility $χ$ and the muon and $\rm ^{63}Cu$ nuclear spin-lattice relaxation rates $1/T_1$ of ${\rm {YbCu_{5-x}Au_x}}$ ($x=0.6$). We show that the above anomalies along with magnetic-field-induced reentrance of LFL properties

Miguel Couceiro, Stephan Foldes

The general Galois theory for functions and relational constraints over arbitrary sets described in the authors&#39; previous paper is refined by imposing algebraic conditions on relations.

Olga Chervova, Dmitri Vassiliev

We suggest an alternative mathematical model for the massless neutrino. Consider an elastic continuum in 3-dimensional Euclidean space and assume that points of this continuum can experience no displacements, only rotations. This framework is a special case of the so-called Cosserat theory of elasticity. Rotations of points of the continuum are described by

Hung Yean Loke, Gordan Savin

In this paper we develop representation theory of the two fold central extension of SL(2) over the field of 2-adic numbers. As a consequence, we obtain a local Shimura correspondence between the two fold central extension of SL(2) and the linear group PGL(2), which we show to be compatible with the global Shimura correspondence at p=2.

Jianqiang Zhao, Xia Zhou

In this paper, we shall show that certain signed cyclic sums of Mordell-Tornheim L-values are rational linear combinations of products of multiple L-values of lower depths (i.e., reducible). This simultaneously generalizes some results of Subbarao and Sitaramachandrarao, and Matsumoto et al. As a direct corollary, we can prove that for any integer k>2 and po

Victor Chepoi, M. Seston

In this paper, we present a factor 16 approximation algorithm for the following NP-hard distance fitting problem: given a finite set X and a distance d on X, find a Robinsonian distance dR on X minimizing the l\infty-error ||d - dR||\infty = maxx,y\epsilonX {|d(x, y) - dR(x, y)|}. A distance dR on a finite set X is Robinsonian if its matrix can be symmetrica

Ho-Leung Chan, Jeff Edmonds, Tak-Wah Lam, Lap-Kei Lee

We study online nonclairvoyant speed scaling to minimize total flow time plus energy. We first consider the traditional model where the power function is P (s) = s\^\propto. We give a nonclairvoyant algorithm that is shown to be O(\propto\^3)-competitive. We then show an Ω(\propto\^(1/3-ε)) lower bound on the competitive ratio of any nonclairvoyant algorithm

Baptiste Jeudy, François Rioult

Recently, different works proposed a new way to mine patterns in databases with pathological size. For example, experiments in genome biology usually provide databases with thousands of attributes (genes) but only tens of objects (experiments). In this case, mining the &#34;transposed&#34; database runs through a smaller search space, and the Galois connecti

Baptiste Jeudy, François Rioult

In this paper, we propose a technique to extract constrained formal concepts.

Tom Hirschowitz, Xavier Leroy, J. B. Wells

This paper formalizes and proves correct a compilation scheme for mutually-recursive definitions in call-by-value functional languages. This scheme supports a wider range of recursive definitions than previous methods. We formalize our technique as a translation scheme to a lambda-calculus featuring in-place update of memory blocks, and prove the translation

Andrei A. Bulatov, Victor Dalmau, Martin Grohe, Daniel Marx

The homomorphism problem for relational structures is an abstract way of formulating constraint satisfaction problems (CSP) and various problems in database theory. The decision version of the homomorphism problem received a lot of attention in literature; in particular, the way the graph-theoretical structure of the variables and constraints influences the

Mahdi Cheraghchi, Amin Shokrollahi

We consider the problem of uniform sampling of points on an algebraic variety. Specifically, we develop a randomized algorithm that, given a small set of multivariate polynomials over a sufficiently large finite field, produces a common zero of the polynomials almost uniformly at random. The statistical distance between the output distribution of the algorit

Laurent Boyer, Guillaume Theyssier

Cellular automata (CA) are dynamical systems defined by a finite local rule but they are studied for their global dynamics. They can exhibit a wide range of complex behaviours and a celebrated result is the existence of (intrinsically) universal CA, that is CA able to fully simulate any other CA. In this paper, we show that the asymptotic density of universa

H. Nemura, N. Ishii, S. Aoki, T. Hatsuda

We study the $\Lambda$-nucleon ($\Lambda N$) force by using lattice QCD. The Bethe-Salpeter amplitude is calculated for the lowest scattering state of the $\Lambda N$ so as to obtain the $\Lambda N$ potential. The numerical calculation is twofold: (i) Full lattice QCD by using 2+1 flavor PACS-CS gauge configurations with, $\beta=1.9$, corresponding to the la

Agnes Bachelot-Motet

We compute the waves propagating on the compact surface of constant negative curvature and genus 2. We adopt a variational approach using finite elements. We have to implement the action of the fuchsian group by suitable boundary conditions of periodic type. A spectral analysis of the wave allows to compute the first eigenvalues of the Laplace-Beltrami opera

M. Ebrahimkhas, S. A. Jafari

In an earlier work we predicted the existence of a neutral triplet collective mode in undoped graphene and graphite [Phys. Rev. Lett. {\bf 89} (2002) 16402]. In this work we study a phenomenological Hamiltonian describing the interaction of tight-binding electrons on honeycomb lattice with such a dispersive neutral triplet boson. Our Hamiltonian is a general

S. Nishimoto, C. Hotta

We show that the two-dimensional density-matrix renormalization analysis is useful to detect the symmetry breaking in the fermionic model on a triangular lattice. Under the cylindrical boundary conditions with chemical potentials on edge sites, we find that the open edges work as perturbation to select the strongest correlations {\it only in the presence of

Duong Quoc Viet, Truong Thi Hong Thanh

Let S be a finitely generated standard multi-graded algebra over a Noetherian local ring A. This paper first expresses mixed multiplicities of S in term of Hilbert-Samuel multiplicity that explained the mixed multiplicities S as the Hilbert-Samuel multiplicities for quotient modules of S. As an application, we get formulas for the mixed multiplicities of ide

E. Bauer, G. Garbarino

The contribution of Pauli exchange terms to the two--nucleon induced non--mesonic weak decay of $^{12}_Λ$C hypernuclei, $ΛNN\to nNN$ ($N=n$ or $p$), is studied within a nuclear matter formalism implemented in a local density approximation. We have adopted a weak transition potential including the exchange of the complete octets of pseudoscalar and vector mes

L. M. González-Romero, F. Navarro-Lérida

Using a new numerical code with non-uniform adapted mesh, we study the changes produced in the global properties of neutron stars by the motion of matter in crust region during post-glitch epoch. Our numerical analysis shows that these changes may contribute to explain the observed spin-down of rotational frequency.

Zhiping Xu, Kun Xue

Graphene epoxide, with oxygen atoms lining up on pristine graphene sheets, is investigated theoretically in this Letter. Two distinct phases: metastable clamped and unzipped structures are unveiled in consistence with experiments. In the stable (unzipped) phase, epoxy group breaks underneath sp2 bond and modifies the mechanical and electronic properties of g

Masayuki Yamamoto, Yositake Takane, Katsunori Wakabayashi

The low-energy spectrum of graphene nanoribbons with armchair edges (armchair nanoribbons) is described as the superposition of two non-equivalent Dirac points of graphene. In spite of the lack of well-separated two valley structures, the single-channel transport subjected to long-ranged impurities is nearly perfectly conducting, where the backward scatterin

Yaroslav V. Kartashov, Victor A. Vysloukh, Lluis Torner

We put forward a strategy to achieve synthetic nonlinearities where local and nonlocal contributions compete on similar footing, thus yielding intermediate tunable responses ranging from fully local to strongly nonlocal. The physical setting addressed is a semiconductor material with both Kerr and thermal nonlinearities illuminated by a pulse train with suit

Soubhik Chakraborty

This paper has several objectives. First, it separates randomness from lawlessness and shows why even genuine randomness does not imply lawlessness. Second, it separates the question -why should I call a phenomenon random? (and answers it in part one) from the patent question -What is a random sequence? -for which the answer lies in Kolmogorov complexity (wh

R. Citro, A. Minguzzi, F. W. J. Hekking

We propose quantum stirring with a laser beam as a probe of superfluid behavior for a strongly interacting one-dimensional Bose gas confined to a ring. Within the Luttinger liquid theory framework, we calculate the fraction of stirred particles per period as a function of the stirring velocity, the interaction strength and the coupling between the stirring b

Giovanni Borghi, Marco Polini, Reza Asgari, A. H. MacDonald

In single-layer graphene sheets non-local interband exchange leads to a renormalized Fermi-surface effective mass which vanishes in the low carrier-density limit. We report on a comparative study of Fermi surface effective mass renormalization in single-layer and AB-stacked bilayer graphene. We explain why the mass does not approach zero in the bilayer case,

D. Tripathi, S. E. Gibson, J. Qiu, L. Fletcher

AIM: To investigate several partially-erupting prominences to study their relationship with other CME-associated phenomena and to compare these observations with observables predicted by a model of partially-expelled flux ropes (Gibson & Fan, 2006a, b). METHODS: We have studied 6 selected events with partially-erupting prominences using multi wavelength obse

Jacob Linder, Takehito Yokoyama, Asle Sudbø, Matthias Eschrig

We study the proximity-induced superconducting correlations in a normal metal connected to a superconductor when the interface between them is spin-active and the normal metal is ballistic or diffusive. Remarkably, for any interface spin polarization there is a critical interface resistance, above which the conventional even-frequency proximity component van

Anwar. S. AlMuhammad

Relying on the magnetic dipole model of the pulsar, we use the extension of the work of Haxton-Ruffini [31] for single charges by DePaolis-Ingrosso-Qadir [32] for an obliquely rotating magnetic dipole, to incorporate the effect of the gravitational mass. So, by using the numerical and analytical solutions of the differential equation for the radiation, we co

Dirk Kreimer

We study the core Hopf algebra underlying the renormalization Hopf algebra.

Soma Nag, Suparna Dutta, Sujata Tarafdar

We study squeeze flow of two different fluids (castor oil and ethylene glycol) between a pair of glass plates and a pair of perspex plates, under an applied load. The film thickness is found to vary with time as a power-law, where the exponent increases with load. After a certain time interval the area of fluid-solid contact saturates to a constant value. Th

Lalitha Sankar, Yingbin Liang, Narayan Mandayam, H. Vincent Poor

The problem of optimal resource allocation is studied for ergodic fading orthogonal multiaccess relay channels (MARCs) in which the users (sources) communicate with a destination with the aid of a half-duplex relay that transmits on a channel orthogonal to that used by the transmitting sources. Under the assumption that the instantaneous fading state informa

Jian-Sheng Wang, Lifa Zhang

We derive a formula for the thermal conductivity tensor of a ballistic phonon Hall model. It is found that, although the diagonal elements of the conductivity tensor diverge to infinite, the off-diagonal elements are finite,antisymmetric, and odd in magnetic field. The off-diagonal elements are non-zero only if the dynamic matrix of the phonon system breaks

Julián Candia

Irreversible opinion spreading phenomena are studied on small-world and scale-free networks by means of the magnetic Eden model, a nonequilibrium kinetic model for the growth of binary mixtures in contact with a thermal bath. In this model, the opinion of an individual is affected by those of their acquaintances, but opinion changes (analogous to spin flips

Robyn M. Woollands, P. L. Cottrell, A. Udalski

This paper presents the initial results of a multi-site photometric programme to examine the extraordinary behaviour displayed by 18 R Coronae Borealis (RCB) stars in the Magellanic Clouds (MCs). RCB stars exhibit a unique variability whereby they undergo rapid declines of up to several magnitudes. These are thought to be caused by the formation of dust in t

Jianke Yang, D. J. Kaup

Squared eigenfunctions are quadratic combinations of Jost functions and adjoint Jost functions which satisfy the linearized equation of an integrable equation. In this article, squared eigenfunctions are derived for the Sasa-Satsuma equation whose spectral operator is a $3\times 3$ system, while its linearized operator is a $2\times 2$ system. It is shown th

James P. Crutchfield, Christopher J. Ellison, John R. Mahoney

We show why the amount of information communicated between the past and future--the excess entropy--is not in general the amount of information stored in the present--the statistical complexity. This is a puzzle, and a long-standing one, since the latter is what is required for optimal prediction, but the former describes observed behavior. We layout a class

F. J. Heremans, G. D. Fuchs, C. F. Wang, R. Hanson

We report time-dependent photocurrent and transport measurements of sub-bandgap photoexcited carriers in nitrogen-rich (type Ib), single-crystal diamond. Transient carrier dynamics are characteristic of trapping conduction with long charge storage lifetimes of ~3 hours. By measuring the photoexcited Hall effect we confirm that the charge carriers are electro