May 2010 arXiv papers — page 36

Amparo Fúster-Sabater, Pedro García-Mochales

A simple binary model to compute the degree of balancedness in the output sequence of LFSR-combinational generators has been developed. The computational method is based exclusively on the handling of binary strings by means of logic operations. The proposed model can serve as a deterministic alternative to existing probabilistic methods for checking balance

Oleg B. Zaslavskii

We consider a spherically symmetric black hole in equilibrium with surrounding classical matter that is characterized by a nonlinear dependence of the radial pressure p_{r} on the density ρ. We examine under which requirements such an equilibrium is possible. It is shown that if the radial and transverse pressures are equal (Pascal perfect fluid), equation o

Amparo Fúster-Sabater, L. J. García-Villalba

The authors prove that the probability of choosing a nonlinear filter of m-sequences with optimal properties, that is, maximum period and maximum linear complexity, tends assymptotically to 1 as the linear feedback shift register length increases.

Enrique García-Berro, Santiago Torres, Leandro G. Althaus, Isabel Renedo

NGC 6791 is a well studied open cluster1 that it is so close to us that can be imaged down to very faint luminosities. The main sequence turn-off age (~8 Gyr) and the age derived from the termination of the white dwarf cooling sequence (~6 Gyr) are significantly different. One possible explanation is that as white dwarfs cool, one of the ashes of helium burn

Takahito Naito

We investigate the moduli sets of central extensions of H-spaces enjoying inversivity, power associativity and Moufang properties. By considering rational H-extensions, it turns out that there is no relationship between the first and the second properties in general.

Guan Gui, Qun Wan, Wei Peng, Fumiyuki Adachi

Wideband wireless channel is a time dispersive channel and becomes strongly frequency-selective. However, in most cases, the channel is composed of a few dominant taps and a large part of taps is approximately zero or zero. To exploit the sparsity of multi-path channel (MPC), two methods have been proposed. They are, namely, greedy algorithm and convex progr

Guan Gui, An-min Huang, Qun Wan

Wideband wireless channel is a time dispersive channel and becomes strongly frequency-selective. However, in most cases, the channel is composed of a few dominant taps and a large part of taps is approximately zero or zero. They are often called sparse multi-path channels (MPC). Conventional linear MPC methods, such as the least squares (LS), do not exploit

Nick Jones

This paper considers the state of nuclear and radiological security in the UK and abroad and reports on the methods that could be employed by terrorists with radiological or nuclear material to cause destruction. It is shown that despite current safeguards that problems arise due to materials that are unaccounted for and poor implementation of detection regi

Guan Gui, Wei Peng, Qun Wan, Fumiyuki Adachi

Broadband wireless channel is a time dispersive and becomes strongly frequency selective. In most cases, the channel is composed of a few dominant coefficients and a large part of coefficients is approximately zero or zero. To exploit the sparsity of multi-path channel (MPC), there are various methods have been proposed. They are, namely, greedy algorithms,

Marc Peigné, Wolfgang Woess

Consider a proper metric space X and a sequence of i.i.d. random continuous mappings F_n from X to X. It induces the stochastic dynamical system (SDS) X_n^x = F_n(X_{n-1}^x) starting at x in X. In this paper, we study existence and uniqueness of invariant measures, as well as recurrence and ergodicity of this process. In the first part, we elaborate, improve

K. S. Vasu, Biswanath Chakraborty, S. Sampath, A. K. Sood

We demonstrate top-gated field effect transistor made of reduced graphene oxide (RGO) monolayer (graphene) by dielectrophoresis. Raman spectrum of RGO flakes of typical size of 5μm x 5μm show a single 2D band at 2687 cm-1, characteristic of a single layer graphene. The two probe current - voltage measurements of RGO flakes, deposited in between the patterned

Matthias Vigelius, Andrew Melatos

The electrical resistivity of the accreted mountain in a millisecond pulsar is limited by the observed spin-down rate of binary radio millisecond pulsars (BRMSPs) and the spins and X-ray fluxes of accreting millisecond pulsars (AMSPs). We find $η\ge 10^{-28}\,\mathrm{s}\, (τ_\mathrm{SD}/1\,\mathrm{Gyr})^{-0.8}$ (where $τ_\mathrm{SD}$ is the spin-down age) fo

Matilde Marcolli, Elena Pierpaoli, Kevin Teh

The spectral action functional, considered as a model of gravity coupled to matter, provides, in its non-perturbative form, a slow-roll potential for inflation, whose form and corresponding slow-roll parameters can be sensitive to the underlying cosmic topology. We explicitly compute the non-perturbative spectral action for some of the main candidates for co

Jorgen Rasmussen

We consider Kerr-Newman-AdS-dS black holes near extremality and work out the near-horizon geometry of these near-extremal black holes. We identify the exact U(1)_L x U(1)_R isometries of the near-horizon geometry and provide boundary conditions enhancing them to a pair of commuting Virasoro algebras. The conserved charges of the corresponding asymptotic symm

Masayuki Tanaka, Carlos De Breuck, Bram Venemans, Jaron Kurk

We report on the environmental dependence of galaxy properties at z=2.15. We construct multi-band photometric data sets in the (proto-)cluster PKS1138-26 field and in the GOODS field. We then fit spectral energy distributions of the galaxies with model templates generated with the latest stellar population synthesis code and derive physical properties of gal

Onur Sahin, Osvaldo Simeone, Elza Erkip

A Gaussian interference channel (IC) aided by a half-duplex relay is considered, in which the relay receives and transmits in an orthogonal band with respect to the IC. The system thus consists of two parallel channels, the IC and the channel over which the relay is active, which is referred to as Out-of-Band Relay Channel (OBRC). The OBRC is operated by sep

V. G. Ivanov, M. N. Iliev, Y. -H. A. Wang, A. Gupta

The lattice dynamics of the ferromagnetic spinel CuCr2Se4 (Tc = 430K) was studied experimentally by measuring the Raman spectra and theoretically by calculation of zone center phonon frequencies within a shell model. All Raman allowed modes (A1g + E_g + 3F2g) were identified and assigned to specific atomic motions. The relative intensity of the Raman lines v

V. G. Ivanov, M. V. Abrashev, M. N. Iliev, M. M. Gospodinov

The Raman spectra of single crystals of NiFe2O4 were studied in various scattering configurations in close comparison with the corresponding spectra of Ni0.7Zn0.3Fe2O4 and Fe3O4. The number of experimentally observed Raman modes exceeds significantly that expected for a normal spinel structure and the polarization properties of most of the Raman lines provid

Huan Xu, Shie Mannor

We derive generalization bounds for learning algorithms based on their robustness: the property that if a testing sample is "similar" to a training sample, then the testing error is close to the training error. This provides a novel approach, different from the complexity or stability arguments, to study generalization of learning algorithms. We furt

Gareth W. Peters, Geoff R. Hosack, Keith R. Hayes

We develop a novel advanced Particle Markov chain Monte Carlo algorithm that is capable of sampling from the posterior distribution of non-linear state space models for both the unobserved latent states and the unknown model parameters. We apply this novel methodology to five population growth models, including models with strong and weak Allee effects, and

Ataru Tanikawa, Toshiyuki Fukushige

We investigate effects of hardness of primordial binaries on whole evolution of star clusters by means of N-body simulations. Using newly developed code, GORILLA, we simulated eleven N=16384 clusters with primordial binaries whose binding energies are equal in each cluster in range of 1-300kT_0, where 1.5kT_0 is average stellar kinetic energy at the initial

Kenta Kiuchi, Hiroki Nagakura, Shoichi Yamada

We present a new formula to numerically construct configurations in rotational equilibrium, which consist of multiple layers. Each layer rotates uniformly or differentially according to cylindrical rotation-laws that are different from layer to layer. Assuming a different barotropic equation of state (EOS) for each layer, we solve the Bernoulli equation in e

Xin Liu

We examine the relation between black hole accretion and bulge star formation as a function of look-back time (tau) in 20,541 obscured AGNs (with redshifts <z> ~ 0.1 and bolometric luminosities L_Bol ~ 10^43--10^45 erg s^-1) optically selected from the Sloan Digital Sky Survey (SDSS). To quantify the most recently formed stars with ages less than typical AGN

Paul Hodge, Karl Krienke

From inspection of 30 Hubble Space Telescope ACS images of M31, we provide a catalog of 449 galaxies seen through the spiral disk. Measurements of the positions of the galaxies, their integrated magnitudes in two colors and their sizes, determined from isophotometry, are included in the catalog. We discuss the many difficulties of interpreting these data in

Sergio L. Cacciatori, Bianca L. Cerchiai, Alessio Marrani

Starting from the symplectic construction of the Lie algebra e_7(7) due to Adams, we consider an Iwasawa parametrization of the coset E_7(7)/SU(8), which is the scalar manifold of N=8, d=4 supergravity. Our approach, and the manifest off-shell symmetry of the resulting symplectic frame, is determined by a non-compact Cartan subalgebra of the maximal subgroup

Thomas Hangelbroek, Fran J. Narcowich, Joe D. Ward

The purpose of this paper is to establish that for any compact, connected C^{\infty} Riemannian manifold there exists a robust family of kernels of increasing smoothness that are well suited for interpolation. They generate Lagrange functions that are uniformly bounded and decay away from their center at an exponential rate. An immediate corollary is that th

Nathanial P. Brown, Wilhelm Winter

Uffe Haagerup proved that quasitraces on unital exact C* -algebras are traces. We give a short proof under the stronger hypothesis of finite nuclear dimension.

Angélica Osorno

We show how to construct a Gamma-bicategory from a symmetric monoidal bicategory, and use that to show that the classifying space is an infinite loop space upon group completion. We also show a way to relate this construction to the classic Gamma-category construction for a bipermutative category. As an example, we use this machinery to construct a delooping

Felix Moya-Anegon, Victor Herrero-Solana

Models for the production of knowledge and systems of innovation and science are key elements for characterizing a country in view of its scientific thematic profile. With regard to scientific output and publication in journals of international visibility, the countries of the world may be classified into three main groups according to their thematic bias. T

The D0 Collaboration, V. Abazov

We report the results of a search for pair production of scalar bottom quarks (sbottom) and scalar third-generation leptoquarks in 5.2 fb-1 of ppbar collisions at the D0 experiment of the Fermilab Tevatron Collider. Scalar bottom quarks are assumed to decay to a neutralino and a $b$ quark, and we set 95% C.L. lower limits on their production in the (m_sbotto

Adrian Dumitrescu, Minghui Jiang, János Pach

The problem of finding &#34;small&#34; sets that meet every straight-line which intersects a given convex region was initiated by Mazurkiewicz in 1916. We call such a set an {\em opaque set} or a {\em barrier} for that region. We consider the problem of computing the shortest barrier for a given convex polygon with $n$ vertices. No exact algorithm is current

Soumik Pal

We prove that probability laws of certain multidimensional semimartingales which includes time-inhomogenous diffusions, under suitable assumptions, satisfy Quadratic Transportation Cost Inequality under the uniform metric. From this we derive concentration properties of Lipschitz functions of process paths that depend on the entire history. In particular, we

Howard Baer, Andrew D. Box, Heaya Summy

We calculate the relic abundance of thermally produced neutralino cold dark matter in the general 19 parameter supergravity (SUGRA-19) model. A scan over GUT scale parameters reveals that models with a bino-like neutralino typically give rise to a dark matter density Ω_{\tz_1}h^2\sim 1-1000, i.e. between 1 and 4 orders of magnitude higher than the measured v

J. R. Mureika, R. B. Mann

If the information transfer between test particle and holographic screen in entropic gravity respects both the uncertainty principle and causality, a lower limit on the number of bits in the universe relative to its mass may be derived. Furthermore, these limits indicate particles that putatively travel at the speed of light -- the photon and/or graviton --

Mitra Osqui, Alexandre Megretski, Mardavij Roozbehani

The paper deals with the task of optimal design of Analog to Digital Converters (ADCs). A general ADC is modeled as a causal discrete-time dynamical system with outputs taking values in a finite set, and its performance is defined as the worst-case average intensity of the filtered input matching error. The design task can be viewed as that of optimal quanti

Peter K. S. Dunsby, Emilio Elizalde, Rituparno Goswami, Sergei Odintsov

Several different explicit reconstructions of f(R) gravity are obtained from the background FRW expansion history. It is shown that the only theory whose Lagrangian is a simple function of the Ricci scalar R, that admits an exact LCDM expansion history is standard General Relativity with a positive cosmological constant and the only way to obtain this behavi

B. Julia-Diaz, J. Martorell, A. Polls

An analytical insight into the symmetry breaking mechanisms underlying the transition from Josephson to self-trapping regimes in Bose-Einstein condensates is presented. We obtain expressions for the ground state properties of the system of a gas of attractive bosons modelized by a two site Bose-Hubbard hamiltonian with an external bias. Simple formulas are f

Jonathan Wahl

Thanks to the recent work of Bhupal, Stipsicz, Szabo, and the author, one has a complete list of resolution graphs of weighted homogeneous complex surface singularities admitting a rational homology disk (&#34;QHD&#34;) smoothing, i.e., one with Milnor number 0. They fall into several classes, the most interesting of which are the three classes whose resolut

Magdalena Larfors, Dieter Lust, Dimitrios Tsimpis

Three-dimensional smooth, compact toric varieties (SCTV), when viewed as real six-dimensional manifolds, can admit G-structures rendering them suitable for internal manifolds in supersymmetric flux compactifications. We develop techniques which allow us to systematically construct G-structures on SCTV and read off their torsion classes. We illustrate our met

Tamara Bogdanovic, Christopher Reynolds, Richard Massey

It has recently been suggested that conduction-driven magnetohydrodynamic (MHD) instabilities may operate at all radii within an intracluster medium (ICM), and profoundly affect the structure of a cluster&#39;s magnetic field. Where MHD instabilities dominate the dynamics of an ICM, they will re-orient magnetic field lines perpendicular to the temperature gr

Charles W. Danforth, Brian A. Keeney, John T. Stocke, J. Michael Shull

We present new far-ultraviolet spectra from the Cosmic Origins Spectrograph (HST/COS) of the BL Lac object 1ES1553+113 covering the wavelength range 1135-1795 A. The data show a smooth continuum with a wealth of narrow absorption features arising in the ISM and IGM. These features include 41 Lya absorbers at 0<z<0.43, fourteen of which are detected in multip

Marco Baldi

We present a complete numerical study of cosmological models with a time dependent coupling between the dark energy component driving the present accelerated expansion of the Universe and the Cold Dark Matter (CDM) fluid. Depending on the functional form of the coupling strength, these models show a range of possible intermediate behaviors between the standa

M. Vaccari, L. Marchetti, A. Franceschini, B. Altieri

Local luminosity functions are fundamental benchmarks for high-redshift galaxy formation and evolution studies as well as for models describing these processes. Determining the local luminosity function in the submillimeter range can help to better constrain in particular the bolometric luminosity density in the local Universe, and Herschel offers the first

Jonathan M. Arnold, Bartosz Fornal, Michael Trott

We examine the prospects for LHC discovery of SU(2)_L singlet vector-like quarks that obey Minimal Flavour Violation (MFV) and are consistent with lower energy phenomenology. We study models where the vector-like quarks have the same quantum numbers as u_R or d_R, allowing mixing, which generally leads to significant low energy constraints. We find that ther

Takeshi Morita

In order to understand thermodynamical properties of N D-branes with chemical potentials associated with R-symmetry charges, we study a one dimensional large N gauge theory (bosonic BFSS type model) as a first step. This model is obtained through a dimensional reduction of a 1+D dimensional SU(N) Yang-Mills theory and we use a 1/D expansion to investigate th

Samuel Lepe, Francisco Pena

We study a holographic model for the dark energy considered recently in the literature which postulates an energy density $ρ\sim R$, where $R$ is the Ricci scalar curvature. We obtain a cosmological scenario that comes from considering two non-interacting fluids along a reasonable Ansatz for the cosmic coincidence parameter. We adjust the involved parameters

Yue Chen, Robert Lipton

A system of periodic poly-disperse coated nano-rods is considered. Both the coated nano-rods and host material are non-magnetic. The exterior nano-coating has a frequency dependent dielectric constant and the rod has a high dielectric constant. A negative effective magnetic permeability is generated near the Mie resonances of the rods while the coating gener

Marios Karouzos, Silke Britzen, Andreas Eckart, Arno Witzel

In the context of the evolution of large structures in the Universe, it is unclear whether active galaxies are a phase which each galaxy undergoes, and what is the importance of the evolution of black holes in their centers. Binary black hole (BBH) systems could play a key role in our understanding of the above question. We investigate the Caltech-Jodrell Ba

Dhiraj Kumar Hazra, Moumita Aich, Rajeev Kumar Jain, L. Sriramkumar

Certain oscillatory features in the primordial scalar power spectrum are known to provide a better fit to the outliers in the cosmic microwave background data near the multipole moments of $\ell=22$ and 40. These features are usually generated by introducing a step in the popular, quadratic potential describing the canonical scalar field. Such a model will b

Rafael M. Fernandes, Jörg Schmalian

We show that, in antiferromagnetic superconductors, the optical spectral weight transferred to low frequencies below the superconducting transition temperature originates from energies that can be much larger than twice the superconducting gap $Δ$. This contrasts to non-magnetic superconductors, where the optical spectrum is suppressed only for frequencies b

D. Batcheldor, A. Robinson, D. J. Axon, E. S. Perlman

Isophotal analysis of M87, using data from the Advanced Camera for Surveys, reveals a projected displacement of 6.8 +/- 0.8 pc (~ 0.1 arcsec) between the nuclear point source (presumed to be the location of the supermassive black hole, SMBH) and the photo-center of the galaxy. The displacement is along a position angle of 307 +/- 17 degrees and is consistent

David Rydh

We show that the pushout of an étale morphism and an open immersion exists in the category of algebraic stacks and show that such pushouts behave similarly to the gluing of two open substacks. For example, quasi-coherent sheaves on the pushout can be described by a simple gluing procedure. We then outline a powerful dévissage method for representable étale m

Pierre Artoisenet, Eric Braaten, Daekyoung Kang

We construct line shapes for the X(3872) that generalize the Flatte and zero-range line shapes that have been considered previously. These line shapes are associated with scattering amplitudes that are exactly unitary for real values of the interaction parameters and can be derived from a renormalizable quantum field theory. The new line shapes can be used t

Chris Clarkson, Roy Maartens

The apparent accelerating expansion of the Universe is forcing us to examine the foundational aspects of the standard model of cosmology -- in particular, the fact that dark energy is a direct consequence of the homogeneity assumption. We discuss the foundations of the assumption of spatial homogeneity, in the case when the Copernican Principle is adopted. W

Brendan Pass

We consider an optimal transportation problem with more than two marginals. We use a family of semi-Riemannian metrics derived from the mixed, second order partial derivatives of the cost function to provide upper bounds for the dimension of the support of the solution.

C. Vignat

In this paper, we reconsider some results by Nieto and Truax about generating functions for arbitrary order coherent and squeezed states. These results were obtained using the exponential of the Laplacian operator; more elaborated operational identities were used by Dattoli et al. \cite{Dattoli} to extend these results. In this note, we show that the operati

Petr Vojcak

We obtain compatible Hamiltonian and symplectic structure for a new two-component fifth-order integrable system recently found by Mikhailov, Novikov and Wang (arXiv:0712.1972), and show that this system possesses a hereditary recursion operator and infinitely many commuting symmetries and conservation laws, as well as infinitely many compatible Hamiltonian a

Bhubanjyoti Bhattacharya, Jonathan L. Rosner

Charmed meson decays to a light pseudoscalar ($P$) and light vector ($V$) meson are analyzed taking account of $η$--$η&#39;$ mixing. A frequently-used octet-singlet mixing angle of $19.5^\circ$ is compared with a value of $11.7^\circ$ favored by a recent analysis of $D \to PP$ decays.

Cedric M. Campos, Manuel de Leon, David Martin de Diego

We develop an intrinsic geometrical setting for higher order constrained field theories. As a main tool we use an appropriate generalization of the classical Skinner-Rusk formalism. Some examples of application are studied, in particular, applications to the geometrical description of optimal control theory for partial differential equations.

Eric Chassande-Mottin, Miriam Miele, Satya Mohapatra, Laura Cadonati

Gravitational Wave (GW) burst detection algorithms typically rely on the hypothesis that the burst signal is &#34;locally stationary&#34;, that is it changes slowly with frequency. Under this assumption, the signal can be decomposed into a small number of wavelets with constant frequency. This justifies the use of a family of sine-Gaussian templates in the O

Rui Albuquerque

Natural metric structures on tangent bundles and tangent sphere bundles enclose many important problems, from the topology of the base to the determination of their holonomy. We make here a brief study of the topic. We find the characteristic classes of some of those structures. We solve the question of when two given tangent sphere bundles S_rM of a Riemann

Wieslaw A. Dudek, Mohammad Shahryari

In this article, we introduce the notion of representations of polyadic groups and we investigate the connection between these representations and those of retract groups and covering groups.

Salvador Robles-Perez, Pedro F. Gonzalez-Diaz

A third quantization formalism is applied to a simplified multiverse scenario. A well defined quantum state of the multiverse is obtained which agrees with standard boundary condition proposals. These states are found to be squeezed, and related to accelerating universes: they share similar properties to those obtained previously by Grishchuk and Siderov. We

B. Abdullaev, C. -H. Park, M. M. Musakhanov

Recently, Gomes et al. [1] have visualized the gap formation in nanoscale regions (NRs) above the critical temperature T_c in the high-T_c superconductor Bi_2Sr_2CaCu_2O_{8+δ}. It has been found that, as the temperature lowers, the NRs expand in the bulk superconducting state consisted of inhomogeneities. The fact that the size of the inhomogeneity [2] is cl

Viktor Eisler, Ingo Peschel

We study the ground-state entanglement of two halves of a critical transverse Ising chain, separated by an interface defect. From the relation to a two-dimensional Ising model with a defect line we obtain an exact expression for the continuously varying effective central charge. The result is relevant also for other fermionic chains.

Holger Partsch

We study deformation theory of elliptic fibre bundles over curves in positive characteristics. As applications, we give examples of non-liftable elliptic surfaces in charactertic two and three, which answers a question of Katsura and Ueno. Also, we construct a class of elliptic fibrations, whose liftability is equivalent to a conjecture of F. Oort concerning

A. A. Chepizhko, V. L. Kulinskii

The Vicsek model for the self-propelled particles is investigated with the respect to the introduction of the stochastic perturbation of the dynamics. It is shown that such a dependence can be thought in terms of the isomorphism of the Vicsek model with the Kuramoto model of spontaneous synchronization. They are isomorphic at least within the mean-field appr

V. Krejcirik, A. Cieply, A. Gal

DWIA calculations of Lambda-hypernuclear production rates in stopped K- reactions on several p-shell targets used recently in experiments by the FINUDA Collaboration are reported. Chirally motivated K- + N -> pion + Lambda in-medium transition amplitudes are employed and the sensitivity of the calculated rates to the initial K- atomic wavefunctions and final

T. J. Williams, A. A. Aczel, E. Baggio-Saitovitch, S. L. Bud&#39;ko

We report muon spin rotation ($μ$SR) measurements of single crystal Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ and Sr(Fe$_{1-x}$Co$_x$)$_2$As$_2$. From measurements of the magnetic field penetration depth $λ$ we find that for optimally- and over-doped samples, $1/λ(T\to 0)^2$ varies monotonically with the superconducting transition temperature T$_{\rm C}$. Within the su

Haoyang Wu

[J. Moore and R. Repullo, \emph{Econometrica} \textbf{58} (1990) 1083-1099] and [B. Dutta and A. Sen, \emph{Rev. Econom. Stud.} \textbf{58} (1991) 121-128] are two important papers on two-agent Nash implementation. Recently, [H. Wu, Quantum mechanism helps agents combat &#34;bad&#34; social choice rules. \emph{International Journal of Quantum Information}, 2

A. R. Samana, F. Krmpotic, N. Paar, C. A. Bertulani

We extend the formalism of weak interaction processes, obtaining new expressions for the transition rates, which greatly facilitate numerical calculations, both for neutrino-nucleus reactions and muon capture. Explicit violation of CVC hypothesis by the Coulomb field, as well as development of a sum rule approach for the inclusive cross sections have been wo

Jeff Achter

It has long been known that to a complex cubic surface or threefold one can canonically associate a principally polarized abelian variety. We give a construction which works for cubics over an arithmetic base. This answers, away from the prime 2, an old question of Deligne and a recent question of Kudla and Rapoport. We further classify the Mumford-Tate grou

Cornelis Jacominus van der Beek, Marcin Konczykowski, Shigeru Kasahara, Takahito Terashima

Charge doping of iron-pnictide superconductors leads to collective pinning of flux vortices, whereas isovalent doping does not. Moreover, flux pinning in the charge-doped compounds is consistently described by the mean-free path fluctuations introduced by the dopant atoms, allowing for the extraction of the elastic quasiparticle scattering rate. The absence

D. Caprioli, Hyesung Kang, A. Vladimirov, T. W. Jones

We provide a both qualitative and quantitative comparison among different approaches aimed to solve the problem of non-linear diffusive acceleration of particles at shocks. In particular, we show that state-of-the-art models (numerical, Monte Carlo and semi-analytical), even if based on different physical assumptions and implementations, for typical environm

Didier Poilblanc

Bipartite entanglement measures are fantastic tools to investigate quantum phases of correlated electrons. Here, I analyze the entanglement spectrum of **gapped** two-leg quantum Heisenberg ladders on a periodic ribbon partitioned into two identical periodic chains. Comparison of various entanglement entropies proposed in the literature is given. The entangl

Jin-Li Guo

In the study of complex networks almost all theoretical models have the property of infinite growth, but the size of actual networks is finite. According to statistics from the China Internet IPv4 (Internet Protocol version 4) addresses, this paper proposes a forecasting model by using S curve (Logistic curve). The growing trend of IPv4 addresses in China is

Hai Wang

To examine the role of magnetism in superconductivity of iron-based superconductors, we first present first-principles optical calculations on three representative parent compounds: LaFeAsO, BaFe2As2 and LiFeAs. Both nonmagnetic (NM) and spin-density wave (SDW) with striped antiferromagnetic order are considered. Due to their layer structure, these compounds

S. Grandner, S. H. L. Klapp

Using grand-canonical Monte Carlo simulations we investigate the impact of charged walls on the crystallization properties of charged colloidal suspensions confined between these walls. The investigations are based on an effective model focussing on the colloids alone. Our results demonstrate that the fluid-wall interaction stemming from charged walls has a

Xiaoting Wang, Sophie G. Schirmer

A simple scheme is presented for achieving effectively maximal pure-state entanglement between non-interacting atoms through purely collective decay and controlled symmetry breaking. The scheme requires no measurements or feedback or even knowledge of the initial states of the atoms. It relies on breaking the symmetry of the system Hamiltonian to ensure the

Jie-Qiao Liao, Jin-Feng Huang, Le-Man Kuang, C. P. Sun

We study coherent energy transfer of a single excitation and quantum entanglement in a dimer, which consists of a donor and an acceptor modeled by two two-level systems. Between the donor and the acceptor, there exists a dipole-dipole interaction, which provides the physical mechanism for coherent energy transfer and entanglement generation. The donor and th

Martin Könenberg, Oliver Matte, Edgardo Stockmeyer

We consider a hydrogen-like atom in a quantized electromagnetic field which is modeled by means of a no-pair operator acting in the positive spectral subspace of the free Dirac operator minimally coupled to the quantized vector potential. We prove that the infimum of the spectrum of the no-pair operator is an evenly degenerate eigenvalue. In particular, we s

Stephen J. Willson

Since Darwin, species trees have been used as a simplified description of the relationships which summarize the complicated network $N$ of reality. Recent evidence of hybridization and lateral gene transfer, however, suggest that there are situations where trees are inadequate. Consequently it is important to determine properties that characterize networks c

Laura Cano-Cortes, Jaime Merino, Simone Fratini

We consider quantum critical points (QCP) in which quantum fluctuations associated with charge rather than magnetic order induce unconventional metallic properties. Based on finite-T calculations on a two-dimensional extended Hubbard model we show how the coherence scale T* characteristic of Fermi liquid behavior of the homogeneous metal vanishes at the onse

Alvin Kiswandhi, Ju-Jun Xie, Shin Nan Yang

We study whether the nonmonotonic behavior found in the differential cross section of the phi-meson photoproduction near threshold can be described by a resonance. Namely, we add a resonance to a model consisting of Pomeron and (pi,eta) exchange by fiat and see if, with a suitable assignment of spin and parity, mass and width, as well as the coupling constan

Friedemann Brandt

The primitive elements of the supersymmetry algebra cohomology as defined in a previous paper are computed for standard supersymmetry algebras in four and five dimensions, for all signatures of the metric and any number of supersymmetries.

F. Pang, X. J. Liang, Z. L. Liao, S. L. Yin

Transport characteristics of single crystal bismuth films on Si(111)-7 \times 7 are found to be metallic or insulating at temperature below or above TC, respectively. The transition temperature TC decreases as the film thickness increases. By combining thickness dependence of the films resistivity, we find the insulating behavior results from the states insi

Daniel Kolbe, Martin Scheid, Andreas Koglbauer, Jochen Walz

The first continuous-wave two-photon absorption laser-induced stimulated emission (CTALISE) is demonstrated. The 7^1S-6^1P transition in mercury at 1014nm wavelength is used and selective lasing of different isotopes is observed.

L. Rosales, W. Barreto, C. Peralta, B. Rodrí guez-Mueller

We apply the postquasistatic approximation, an iterative method for the evolution of self-gravitating spheres of matter, to study the evolution of dissipative and electrically charged distributions in General Relativity. We evolve nonadiabatic distributions assuming an equation of state that accounts for the anisotropy induced by the electric charge. Dissipa

Niels Leth Gammelgaard

We give an explicit local formula for any formal deformation quantization, with separation of variables, on a Kähler manifold. The formula is given in terms of differential operators, parametrized by acyclic combinatorial graphs.

Maciej Borodzik, Andras Nemethi

Based on some analogies with the Hodge theory of isolated hypersurface singularities, we define Hodge-type numerical invariants (called H-numbers) of any, not necessarily algebraic, link in $S^3$. They contain the same information as the (normalized) real Seifert matrix. We study their basic properties, we express the Tristram-Levine signatures and the highe

S. Salimi, A. Mohammadzade, K. Berrada

A simplified expression of concurrence for two-qubit mixed state having no more than three non-vanishing eigenvalues is obtained. Basing on SU(2) coherent states, the amount of entanglement of two-qubit pure states is studied and conditions for entanglement are calculated by formulating the measure in terms of some new parameters (amplitudes of coherent stat

Lorenzo Iorio

The strategy followed so far in the performed or proposed tests of the general relativistic Lense-Thirring effect in the gravitational field of the Earth with laser-ranged satellites of LAGEOS type relies upon the cancelation of the disturbing huge precessions induced by the first even zonal harmonic coefficient J_2 of the multipolar expansion of the Newtoni

Peter H. van der Kamp, G. R. W. Quispel

We show, in full generality, that the staircase method provides integrals for mappings, and correspondences, obtained as traveling wave reductions of (systems of) integrable partial difference equations. We apply the staircase method to a variety of equations, including the Korteweg-De Vries equation, the five-point Bruschi-Calogero-Droghei equation, the QD-

Elena Kartashova, Alexey Kartashov

Kinetic regime of capillary wave turbulence is classically regarded in terms of three-wave interactions with the exponent of power energy spectrum being $ν=-7/4$ (two-dimensional case). We show that a number of assumptions necessary for this regime to occur can not be fulfilled. Four-wave interactions of capillary waves should be taken into account instead,

Vivek K. Jain, Manoj K. Yadav

An automorphism $α$ of a group $G$ is said to be central if $α$ commutes with every inner automorphism of $G$. We construct a family of non-special finite $p$-groups having abelian automorphism groups. These groups provide counter examples to a conjecture of A. Mahalanobis [Israel J. Math., {\bf 165} (2008), 161 - 187]. We also construct a family of finite $

Nikola Zlatanov, Zoran Hadzi-Velkov, George K. Karagiannidis, Robert Schober

The outage probability is an important performance measure for cooperative diversity schemes. However, in mobile environments, the outage probability does not completely describe the behavior of cooperative diversity schemes since the mobility of the involved nodes introduces variations in the channel gains. As a result, the capacity outage events are correl

A. L. Kataev

As was discovered recently, 5-loop perturbative quenched QED approximation to the QED $β$-function consist from the rational term and the term proportional to $ζ(3)$-function. It is stressed, that this feature is also manifesting itself in the conformal invariant pqQED series for the 4-loop approximation to the anomalous mass dimension. The 4-loop pqQED expr

Tsuyoshi Miezaki

In 1947, Lehmer conjectured that the Ramanujan τ-function τ(m) is non-vanishing for all positive integers m, where τ(m) are the Fourier coefficients of the cusp form Δof weight 12. It is known that Lehmer&#39;s conjecture can be reformulated in terms of spherical t-design, by the result of Venkov. In this paper, we show that τ(m) = 0 is equivalent to the fac

Richard Lärkäng, Håkan Samuelsson

We describe various approaches to Coleff-Herrera products of residue currents $R^j$ (of Cauchy-Fantappiè-Leray type) associated to holomorphic mappings $f_j$. More precisely, we study to which extent (exterior) products of natural regularizations of the individual currents $R^j$ yield regularizations of the corresponding Coleff-Herrera products. Our results

B. G. Konopelchenko, G. Ortenzi

Algebraic and geometric structures associated with Birkhoff strata of Sato Grassmannian are analyzed. It is shown that each Birkhoff stratum $Σ_S$ contains a subset $W_{\hat{S}}$ of points for which each fiber of the corresponding tautological subbundle $TB_{W_S}$ is closed with respect to multiplication. Algebraically $TB_{W_S}$ is an infinite family of inf