March 2010 arXiv papers — page 38

C. A. F. Vaz, E. I. Altman, V. E. Henrich

A detailed study of the exchange bias effect and the interfacial electronic structure in Ni/Co3O4(011) is reported. Large exchange anisotropies are observed at low temperatures, and the exchange bias effect persists to temperatures well above the Neel temperature of bulk Co3O4, of about 40 K: to ~80 K for Ni films deposited on well ordered oxide surfaces, an

Paul Larson, Saharon Shelah

Working in the context of restricted forms of the Axiom of Choice, we consider the problem of splitting the ordinals below $λ$ of cofinality $θ$ into $λ$ many stationary sets, where $θ< λ$ are regular cardinals. This is a continuation of \cite{Sh835}.

Paul S. Wesson

The main results are reviewed of relating the scalar field of noncompactified Kaluza-Klein gravity to the Higgs field of particle physics. The embedding of 4D spacetime in a 5D manifold can result in a variable cosmological &#39;constant&#39; and particle masses tiny compared to the Planck value.

James Brannick, Durkbin Cho

We construct and analyze a preconditioner of the linear elastiity system discretized by conforming linear finite elements in the framework of the auxiliary space method. The auxiliary space preconditioner is based on discretization of a scalar elliptic equation with Generalized Finite Element Method.

Eiji Ogasa

This paper gives a new obstruction for ribbon-move equivalence of 2-knots. Let $K$ and $K&#39;$ be 2-knots. Let $K$ and $K&#39;$ are ribbon-move equivalent. One corollary to our main theorem is as follows. A 2-dimensional fibered knot whose fiber is the punctured 3-dimensional torus is not ribbon-move equivalent to any 2-dimensional knot whose Seifert hypers

Fangwen Fu, Mihaela van der Schaar

In this paper, we consider the problem of real-time transmission scheduling over time-varying channels. We first formulate the transmission scheduling problem as a Markov decision process (MDP) and systematically unravel the structural properties (e.g. concavity in the state-value function and monotonicity in the optimal scheduling policy) exhibited by the o

Daniel M. Romero, Jon Kleinberg

It has often been taken as a working assumption that directed links in information networks are frequently formed by &#34;short-cutting&#34; a two-step path between the source and the destination -- a kind of implicit &#34;link copying&#34; analogous to the process of triadic closure in social networks. Despite the role of this assumption in theoretical mode

Adrian Carbajal-Dominguez, Jorge Bernal, Alberto Martin-Ruiz, Gabriel Martínez Niconoff

An alternative method to generate J0 Bessel beams with controlled spatial partial coherence properties is introduced. Far field diffraction from a discrete number of source points on an annular region is calculated. The average for different diffracted fields produced at several rotation angles is numerically calculated and experimentally detected. Theoretic

Adilson E. Motter

Research on synchronization of coupled oscillators has helped explain how uniform behavior emerges in populations of non-uniform systems. But explaining how uniform populations engage in sustainable non-uniform synchronization may prove to be just as fascinating.

Nicholas J. Wright, Jeremy J. Drake, Janet E. Drew, Jorick S. Vink

Cygnus OB2 is the nearest example of a massive star forming region, containing over 50 O-type stars and hundreds of B-type stars. We have analysed the properties of young stars in two fields in Cyg OB2 using the recently published deep catalogue of Chandra X-ray point sources with complementary optical and near-IR photometry. Our sample is complete to 1 Msun

Daniel J. H. Chung, Peng Zhou

Just as big bang nucleosynthesis allows us to probe the expansion rate when the temperature of the universe was around 1 MeV, the measurement of gravity waves from electroweak scale first order phase transitions may allow us to probe the expansion rate when the temperature of the universe was at the electroweak scale. We compute the simple transformation rul

Yu Wang, Heng Shen, Xiaoli Jin, Xiaolong Su

We experimentally demonstrated that the quantum correlations of amplitude and phase quadratures between signal and idler beams produced from a non-degenerate optical parametric amplifier (NOPA) can be significantly improved by using a mode cleaner in the pump field and reducing the phase fluctuations in phase locking systems. Based on the two technical impro

Sreenivas Gollapudi, Rina Panigrahy

Click through rates (CTR) offer useful user feedback that can be used to infer the relevance of search results for queries. However it is not very meaningful to look at the raw click through rate of a search result because the likelihood of a result being clicked depends not only on its relevance but also the position in which it is displayed. One model of t

M. Wakamatsu

The recent global analysis of helicity parton distributions, which takes into account available data from inclusive and semi-inclusive polarized deep inelastic scattering, as well as from polarized proton-proton scattering at RHIC, appears to offer the first strong evidence that polarized sea-quark distributions are flavor asymmetric, i.e. $Δ\bar{u}(x) \ne Δ

Rolly Seth, Rishi Kapoor, Hameed Al-Qaheri, Sugata Sanyal

Although &#39;Halcyon&#39; means serene environment which pervasive computing aims at, we have tried to present a different interpretation of this word. Through our approach, we look at it in context of achieving future &#39;calm technology&#39;. The paper gives a general overview of the state of pervasive computing today, proposes the &#39;HALCYON Model&#39

Vasili Perebeinos, Phaedon Avouris

We present a study of transport in graphene devices on polar insulating substrates by solving the Bolzmann transport equation in the presence of graphene phonon, surface polar phonon, and Coulomb charged impurity scattering. The value of the saturated velocity shows very weak dependence on the carrier density, the nature of the insulating substrate, and the

Tuncay Aktosun, Francesco Demontis, Cornelis van der Mee

A systematic method is presented to provide various equivalent solution formulas for exact solutions to the sine-Gordon equation. Such solutions are analytic in the spatial variable $x$ and the temporal variable $t,$ and they are exponentially asymptotic to integer multiples of $2π$ as $x\to\pm\infty.$ The solution formulas are expressed explicitly in terms

A R Usha Devi, Sudha, A. K. Rajagopal

The Majorana representation of symmetric N-qubit states is employed here to investigate how correlation information of the whole pure symmetric state gets imprinted in its parts. It is shown that reduced states of (N - 1) qubits uniquely specify the entire class of pure N qubit states containing two distinct spinors.

Omar Lakkis, Tristan Pryer

We derive energy-norm aposteriori error bounds, using gradient recovery (ZZ) estimators to control the spatial error, for fully discrete schemes for the linear heat equation. This appears to be the first completely rigorous derivation of ZZ estimators for fully discrete schemes for evolution problems, without any restrictive assumption on the timestep size.

Marjana Ležaić, Nicola A. Spaldin

Using density functional calculations we explore the properties of as-yet-unsynthesized $3d - 5d$ ordered double perovskites ($A_2BB&#39;$O$_6$) with highly polarizable Bi$^{3+}$ ions on the $A$ site. We find that the Bi$_2$NiReO$_6$ and Bi$_2$MnReO$_6$ compounds are insulating and exhibit a robust net magnetization that persists above room temperature. When

Seb Oliver, M. Frost, D. Farrah, E. Gonzalez-Solares

We use the Spitzer Wide-area InfraRed Extragalactic Legacy Survey (SWIRE) to explore the specific star-formation activity of galaxies and their evolution near the peak of the cosmic far-infrared (FIR) background at 70 and 160um. We use a stacking analysis to determine the mean FIR properties of well defined subsets of galaxies at flux levels well below the F

Cecilia C. López, Ariel Bendersky, Juan Pablo Paz, David G. Cory

We present in a unified manner the existing methods for scalable partial quantum process tomography. We focus on two main approaches: the one presented in Bendersky et al. [Phys. Rev. Lett. 100, 190403 (2008)], and the ones described, respectively, in Emerson et al. [Science 317, 1893 (2007)] and López et al. [Phys. Rev. A 79, 042328 (2009)], which can be co

Masayuki Asakawa, Abhijit Majumder, Berndt Müller

We discuss various mechanisms for the creation of an asymmetric charge fluctuation with respect to the reaction plane among hadrons emitted in relativistic heavy-ion collisions. We show that such mechanisms exist in both, the hadronic gas and the partonic phases of QCD. The mechanisms considered here all require the presence of a strong magnetic field (the `

Chengming Bai, Li Guo, Xiang Ni

An O-operator is a relative version of a Rota-Baxter operator and, in the Lie algebra context, is originated from the operator form of the classical Yang-Baxter equation. We generalize the well-known construction of dendriform dialgebras and trialgebras from Rota-Baxter algebras to a construction from O-operators. We then show that this construction from O-o

Matteo Viel, Martin G. Haehnelt, Volker Springel

We present a suite of full hydrodynamical cosmological simulations that quantitatively address the impact of neutrinos on the (mildly non-linear) spatial distribution of matter and in particular on the neutral hydrogen distribution in the Intergalactic Medium (IGM), which is responsible for the intervening Lyman-alpha absorption in quasar spectra. The free-s

Dumitru Astefanesei, Maria J. Rodriguez, Stefan Theisen

We investigate the thermodynamic stability of neutral black objects with (at least) two angular momenta. We use the quasilocal formalism to compute the grand canonical potential and show that the doubly spinning black ring is thermodynamically unstable. We consider the thermodynamic instabilities of ultra-spinning black objects and point out a subtle relatio

Jeffrey M. Silverman, Mohan Ganeshalingam, Weidong Li, Alexei V. Filippenko

In this paper, we present and analyse optical photometry and spectra of the extremely luminous and slowly evolving Type Ia supernova (SN Ia) 2009dc, and offer evidence that it is a super-Chandrasekhar mass (SC) SN Ia and thus had a SC white dwarf (WD) progenitor. Optical spectra of SN 2007if, a similar object, are also shown. SN 2009dc had one of the most sl

Carlos Cunha, Dragan Huterer, Olivier Dore

It has recently been proposed that the large-scale bias of dark matter halos depends sensitively on primordial non-Gaussianity of the local form. In this paper we point out that the strong scale dependence of the non-Gaussian halo bias imprints a distinct signature on the covariance of cluster counts. We find that using the full covariance of cluster counts

Simin Feng

We apply the equivalent theory to orthorhombic anisotropic materials and provide a general unit-cell design criterion for achieving a length-independent retrieval of the effective material parameters from a single layer of unit cells. We introduce a graphical retrieval method and phase unwrapping techniques. The graphical method utilizes the linear regressio

Massimiliano Rinaldi

We consider the coherent state approach to non-commutativity, and we derive from it an effective quantum scalar field theory. We show how the non-commutativity can be taken in account by a suitable modification of the Klein-Gordon product, and of the equal-time commutation relations. We prove that, in curved space, the Bogolubov coefficients are unchanged, h

M. Iskin, C. A. R. Sa de Melo

We study ultra-cold neutral fermion superfluids in the presence of fictitious magnetic fields, as well as charged fermion superfluids in the presence of real magnetic fields. Charged fermion superfluids undergo a phase transition from type-I to type-II superfluidity, where the magnetic properties of the superfluid change from being a perfect diamagnet withou

Ping Wong Ng, Efren Ruiz

We study the automorphism group of a unital, simple, $\mathcal{Z}$-stable $C^{*}$-algebra. In this paper, we generalize the results by the authors in \cite{pr_auto} to $\mathcal{Z}$-stable $C^{*}$-algebras $\mathfrak{A}$ such that $\mathfrak{A} \otimes \mathfrak{B}$ is a separable, nuclear, simple, tracially AI algebras satisfying the Universal Coefficient T

G. Adesso, S. Campbell, F. Illuminati, M. Paternostro

We study state engineering through bilinear interactions between two remote qubits and two-mode Gaussian light fields. The attainable two-qubit states span the entire physically allowed region in the entanglement-versus-global-purity plane. Two-mode Gaussian states with maximal entanglement at fixed global and marginal entropies produce maximally entangled t

Karol Palka

We give a survey of results on the geometry of complex algebraic Q-acyclic surfaces, so-called &#39;Q-homology planes&#39;, including some recent results.

C. Lupo, S. Mancini

We address the question of optimality of entangled input states in quantum Gaussian memory channels. For a class of such channels, that can be traced back to the memoryless setting, we state a criterion which relate the optimality of entangled inputs to the symmetry properties of the channels&#39; action. Several examples of channel models belonging to this

W. L. Moreira, A. A. R. Neves, M. K. Garbos, T. G. Euser

Since 1908, when Mie reported analytical expressions for the fields scattered by a spherical particle upon incidence of an electromagnetic plane-wave, generalizing his analysis to the case of an arbitrary incident wave has proved elusive. This is due to the presence of certain radially-dependent terms in the equation for the beam-shape coefficients of the ex

Arnab Saha, Sagar Chakraborty, Jayanta K. Bhattacharjee

We show that the rare events present in dissipated work that enters Jarzynski equality, when mapped appropriately to the phenomenon of large deviations found in a biased coin toss, are enough to yield a quantitative work probability distribution for Jarzynski equality. This allows us to propose a recipe for constructing work probability distribution independ

Babak Shahbaba

High-throughput scientific studies involving no clear a&#39;priori hypothesis are common. For example, a large-scale genomic study of a disease may examine thousands of genes without hypothesizing that any specific gene is responsible for the disease. In these studies, the objective is to explore a large number of possible factors (e.g. genes) in order to id

A. B. Vorontsov, M. G. Vavilov, A. V. Chubukov

We present a detailed description of two-band quasi-2D metals with s-wave superconducting (SC) and antiferromagnetic spin-density wave (SDW) correlations. We present a general approach and use it to investigate the influence of the difference between the shapes and the areas of the two Fermi surfaces on the phase diagram. In particular, we determine the cond

Gian F. Giudice, Paride Paradisi, Alessandro Strumia

We consider the corrections that arise at one loop when integrating out heavy fields in supersymmetric models. We show that, in type-I see-saw models, complex A and B terms of the heavy right-handed neutrino give radiative contributions to the neutron EDM, as well as new dominant contributions to the electron EDM. Type-II and type-III see-saw also predict a

James Barry, Werner Rodejohann

The addition of an A_4 family symmetry and extended Higgs sector to the Standard Model can generate the tribimaximal mixing pattern for leptons, assuming the correct vacuum expectation value alignment of the Higgs scalars. Deviating this alignment affects the predictions for the neutrino oscillation and neutrino mass observables. An attempt is made to classi

Alexis Larranaga

We study the entropy of the Gibbons-Maeda-Garfinkle-Horowitz-Strominger (GMGHS) charged black hole, originated from the effective action that emerges in the low-energy of string theory, beyond semiclassical approximations. Applying the properties of exact differentials for three variables to the first law thermodynamics we derive the quantum corrections to t

Nicholas P. Butch, Kevin Kirshenbaum, Paul Syers, Andrei B. Sushkov

While evidence of a topologically nontrivial surface state has been identified in surface-sensitive measurements of Bi2Se3, a significant experimental concern is that no signatures have been observed in bulk transport. In a search for such states, nominally undoped single crystals of Bi2Se3 with carrier densities approaching 10^16 cm^-3 and very high mobilit

Kenichi Konishi

We discuss some of the latest results concerning the non-Abelian vortices. The first concerns the construction of non-Abelian BPS vortices based on general gauge groups of the form G= G&#39; x U(1). In particular detailed results about the vortex moduli space have been obtained for G&#39;=SO(N) or USp(2N). The second result is about the &#34;fractional vorti

Eric Armengaud

These notes cover some of the topics associated with direct detection of dark matter at an introductory level. The general principles of dark matter search are summarized. The current status of some experiments is described, with an emphasis on bolometric and noble liquid techniques. Plots and illustrations associated to these notes may be found on transpare

Ioannis Iatrakis, Elias Kiritsis, Angel Paredes

We construct a new, simple phenomenological model along the lines of AdS/QCD. The essential new ingredient is the brane-antibrane effective action including the open string tachyon proposed by Sen. Chiral symmetry breaking happens because of tachyon dynamics. We fit a large number of low-spin meson masses at the 10%-15% level. The only free parameters involv

Aditi Kar, Graham A. Niblo

We establish a splitting theorem for one-ended groups H<G such that \tilde{e}(G;H)> 2 and the almost malnormal closure of H is a proper subgroup of G. This yields splitting theorems for groups G with non-trivial first l^2 Betti number (β^2_1(G)). We verify the Kropholler Conjecture for pairs H < G satisfying β^2_1(G) > β^2_1(H). We also prove that every n-di

I. Marti-Vidal, E. Ros, M. A. Perez Torres, J. C. Guirado

Context: Phase referencing is a standard calibration technique in radio interferometry, particularly suited for the detection of weak sources close to the sensitivity limits of the interferometers. However, effects from a changing atmosphere and inaccuracies in the correlator model may affect the phase-referenced images, leading to wrong estimates of source

R. T. Clay, H. Li, S. Sarkar, S. Mazumdar

It has been suggested that the metal-insulator transitions in a number of spinel materials with partially-filled t_2g d-orbitals can be explained as orbitally-driven Peierls instabilities. Motivated by these suggestions, we examine theoretically the possibility of formation of such orbitally-driven states within a simplified theoretical model, a two-dimensio

K. Karami, A. Sorouri

Here we consider the entropy-corrected version of the new agegraphic dark energy model in the non-flat FRW universe. We derive the exact differential equation that determines the evolution of the entropy-corrected new agegraphic dark energy density parameter in the presence of interaction with dark matter. We also obtain the equation of state and deceleratio

Gian F. Giudice, Martti Raidal, Alessandro Strumia

We study bounds and signatures of models where the Higgs doublet has an inhomo- geneous mass or vacuum expectation value, being coupled to a hidden sector that breaks Lorentz invariance. This physics is best described by a low-energy effective Lagrangian in which the Higgs speed-of-light is smaller than c; such effect is naturally small because it is suppres

Stephen Harrap

For any real pair i, j geq 0 with i+j=1 let Bad(i, j) denote the set of (i, j)-badly approximable pairs. That is, Bad(i, j) consists of irrational vectors x:=(x_1, x_2) in R^2 for which there exists a positive constant c(x) such that max {||qx_1||^(-i), ||qx_2||^(-j)} > c(x)/q for all q in N. A new characterization of the set Bad(i, j) in terms of `well-appr

S. B. Emery, C. -J. Cheng, D. Kan, F. J. Rueckert

We have investigated heteroepitaxial films of Sm-doped BiFeO3 with a Sm-concentration near a morphotropic phase boundary. Our high-resolution synchrotron X-ray diffraction, carried out in a temperature range of 25C to 700C, reveals substantial phase coexistence as one changes temperature to crossover from a low-temperature PbZrO3-like phase to a high-tempera

Ivan V. Arzhantsev

Let G be a semisimple affine algebraic group and P a parabolic subgroup of G. We classify all flag varieties G/P which admit an action of the commutative unipotent group G_a^n with an open orbit.

Lionel Maréchal, Jérôme Perez

This paper is devoted to Radial Orbit Instability in the context of self-gravitating dynamical systems. We present this instability in the new frame of Dissipation-Induced Instability theory. This allows us to obtain a rather simple proof based on energetics arguments and to clarify the associated physical mechanism.

Johannes Brunnemann, David Rideout

We analyze combinatorial structures which play a central role in determining spectral properties of the volume operator in loop quantum gravity (LQG). These structures encode geometrical information of the embedding of arbitrary valence vertices of a graph in 3-dimensional Riemannian space, and can be represented by sign strings containing relative orientati

Michael Kastner

Motivated by the anisotropic long-range nature of the interactions between cold dipolar atoms or molecules in an optical lattice, we study the anisotropic quantum Heisenberg model with Curie-Weiss-type long-range interactions. Absence of a heat bath in optical lattice experiments suggests a study of this model within the microcanonical ensemble. The microcan

M. Petrič, M. Starič

We search for the flavor-changing neutral current decays D0\to mu+mu- and D0\to e+e-, and for the lepton-flavor violating decays D0\to e\pm mu\mp using 660 fb^-1 of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find no evidence for any of these decays. We obtain significantly improved upper limits on the branching fra

Joerg Schuermann

In this paper we give an introduction to our recent work on characteristic classes of complex hypersurfaces based on some talks given at conferences in Strasbourg, Oberwolfach and Kagoshima. We explain the relation between nearby cycles for constructible functions or sheaves as well as for (relative) Grothendieck groups of algebraic varieties and mixed Hodge

Markus M. Hohle, Ralph Neuhaeuser, Bernard F. Schutz

Massive stars are of interest as progenitors of super novae, i.e. neutron stars and black holes, which can be sources of gravitational waves. Recent population synthesis models can predict neutron star and gravitational wave observations but deal with a fixed super nova rate or an assumed initial mass function for the population of massive stars. Here we inv

Morgan Fouesneau, Ariane Lançon

Star clusters are studied widely both as benchmarks for stellar evolution models and in their own right. Cluster age and mass distributions within galaxies are probes of star formation histories, and of cluster formation and disruption processes. The vast majority of clusters in the Universe is small, and it is well known that the integrated fluxes and color

C. Curceanu, J. Marton

Mini-proceedings of the ECT* Workshop, Hadronic Atoms and Kaonic Nuclei - Solved Puzzles, Open Problems and Future Challenges in Theory and Experiment, 12-16 October 2009

Harald Grobner

In this paper we fully describe the cuspidal and the Eisenstein cohomology of the group $G=GL_2$ over a definite quaternion algebra $D/\Q$. Functoriality is used to show the existence of residual and cuspidal automorphic forms, having cohomology in degree 1. The latter ones turn out to be CAP-representations, though $G$ satisfies Strong Multiplicity One. A n

O. B. Zaslavskii

It is shown that in non-linear electrodynamics (in particular, Born-Infeld one) in the framework of general relativity there exist &#34;weakly singular&#34; configurations such that (i) the proper mass M is finite in spite of divergences of the energy density, (ii) the electric charge q and Schwarzschild mass m ~ q can be made as small as one likes, (iv) all

Thomas Barthel, Martin Kliesch, Jens Eisert

Real-space renormalization approaches for quantum lattice systems generate certain hierarchical classes of states that are subsumed by the multi-scale entanglement renormalization ansatz (MERA). It is shown that, with the exception of one spatial dimension, MERA states are actually finitely correlated states, i.e., projected entangled pair states (PEPS) with

Marie-Claude Arnaud

Let H be a Tonelli Hamiltonian defined on the cotangent bundle of a compact and connected manifold and let u be a semi-concave function defined on M. If E (u) is the set of all the super-differentials of u and (ϕt) the Hamiltonian flow of H, we prove that for t > 0 small enough, ϕ-t (E (u)) is an exact Lagrangian Lipschitz graph. This provides a geometric in

Federico Piazza, Maxim Pospelov

The Higgs portal of the Standard Model provides the opportunity for coupling to a very light scalar field $ϕ$ via the super-renormalizable operator $ϕ(H^\dagger H)$. This allows for the existence of a very light scalar dark matter that has coherent interaction with the Standard Model particles and yet has its mass protected against radiative corrections. We

Rabin Banerjee, Bibhas Ranjan Majhi

Starting from the definition of entropy used in statistical mechanics we show that it is proportional to the gravity action. For a stationary black hole this entropy is expressed as $S = E/ 2T$, where $T$ is the Hawking temperature and $E$ is shown to be the Komar energy. This relation is also compatible with the generalised Smarr formula for mass.

Matteo Giordano, Robi Peschanski

Using the AdS/CFT correspondence, we study the high-energy behavior of colorless dipole elastic scattering amplitudes in N=4 SYM gauge theory through the Wilson loop correlator formalism and Euclidean to Minkowskian analytic continuation. The purely elastic behavior obtained at large impact-parameter L, through duality from disconnected AdS_5 minimal surface

Ahmad Erfanian, Rashid Rezaei, Francesco G. Russo

The purpose of the present paper is to consider the notion of isoclinism between two finite groups and its generalization to n-isoclinism, introduced by J. C. Bioch in 1976. A weaker form of n-isoclinism, called relative n-isoclinism, will be discussed. This will allow us to improve some classical results in literature. We will point out the connections betw

Rainer Stiele, Tillmann Boeckel, Jürgen Schaffner-Bielich

We investigate cosmological constraints on an energy density contribution of elastic dark matter self-interactions characterized by the mass of the exchange particle and coupling constant. Because of the expansion behaviour in a Robertson-Walker metric we investigate self-interacting dark matter that is warm in the case of thermal relics. The scaling behavio

V. M. Petechuk

The conditions for stability of the elements of linear groups over the associative rings with identity and their connection with the stability of rings are analyzed in the article. The stability of rings which are commutative, satisfy the conditions of stability of rank $\geq 2$, von Neumann regular, integer-algebraic, nearly local rings introduced by the au

Klas Hultqvist

The IceCube observatory is the first cubic kilometre scale instrument in the field of high-energy neutrino astronomy and cosmic rays. In 2009, following five successful deployment seasons, IceCube consisted of 59 strings of optical modules in the South Pole ice, together with 118 air shower detectors in the IceTop surface array. The range of physics topics i

Sofiane Bourouaine, Eckart Marsch, Fritz M. Neubauer

Correlations are studied between the power density of transverse waves having frequencies between $0.01$ and $1$ normalized to the proton gyrofrequency in the plasma frame and the ratio of the perpendicular and parallel temperature of the protons. The wave power spectrum is evaluated from high-resolution 3D magnetic field vector components, and the ion tempe

Rashid Rezaei, Francesco G. Russo

P. Hall introduced the notion of isoclinism between two groups more than 60 years ago. Successively, many authors have extended such a notion in different contexts. The present paper deals with the notion of relative n-isoclinism, given by N. S. Hekster in 1986, and with the notion of n-th relative nilpotency degree, recently introduced in literature.

Amir H. Abbassi, Amir M. Abbassi

We have investigated the vacuum maximally symmetric solutions of recently proposed density-metric unimodular gravity theory,the results are widely different from inflationary senario.The exponential dependence on time in deSitter space is substiuted by a power law. Open space-times with non-zero cosmological constant are excluded in this theory

Jean-Baptiste Aubin, Samuela Leoni-Aubin

A simple test is proposed for examining the correctness of a given completely specified response function against unspecified general alternatives in the context of univariate regression. The usual diagnostic tools based on residuals plots are useful but heuristic. We introduce a formal statistical test supplementing the graphical analysis. Technically, the

A. Gorsky, P. N. Kopnin, A. V. Zayakin

The essence of the chiral magnetic effect is generation of an electric current along an external magnetic field. Recently it has been studied by Rebhan et al. within the Sakai--Sugimoto model, where it was shown to be zero. As an alternative, we calculate the chiral magnetic effect in soft-wall AdS/QCD and find a non-zero result with the natural boundary con

Johan Bredberg

This text shows the existence of large (3.54 times the average) gaps between consecutive zeros, on the critical line, of some Dirichlet $L$-functions $L(s,χ),$ with $χ$ being an even primitive Dirichlet character.

Mireia Besalú, Carles Rovira

In this note we prove an existence and uniqueness result for the solution of multidimensional stochastic delay differential equations with normal reflection. The equations are driven by a fractional Brownian motion with Hurst parameter $H>1/2$. The stochastic integral with respect to the fractional Brownian motion is a pathwise Riemann--Stieltjes integral.

G. Tackmann, M. Gilowski, Ch. Schubert, P. Berg

We report on the phase-locking of two diode lasers based on self-seeded tapered amplifiers. In these lasers, a reduction of linewidth is achieved using narrow-band high-transmission interference filters for frequency selection. The lasers combine a compact design with a Lorentzian linewidth below 200 kHz at an output power of 300 mW. We characterize the phas

Zsolt Langi

A real semi-inner-product space is a real vector space $\M$ equipped with a function $[.,.] : \M \times \M \to \Re$ which is linear in its first variable, strictly positive and satisfies the Schwartz inequality. It is well-known that the function $||x|| = \sqrt{[x,x]}$ defines a norm on $\M$. and vica versa, for every norm on $X$ there is a semi-inner-produc

Rafael Potrie

We present new examples of generic diffeomorphisms without attractors. Also, we study how these wild classes are accumulated by infinitely many other classes (obtaining that the chain recurrence classes different from the only quasi-attractor are contained in center stable manifolds). The construction relies on some derived from Anosov (DA) constructions and

Anirban Guha, Ronald M. Barron, Ram Balachandar

Numerical simulation of high-speed turbulent water jets in air and its validation with experimental data has not been reported in the literature. It is therefore aimed to simulate the physics of these high-speed water jets and compare the results with the existing experimental works. High-speed water jets diffuse in the surrounding atmosphere by the processe

Martijn Caspers, Erik Koelink

We give a formula for the modular operator and modular conjugation in terms of matrix coefficients of corepresentations of a quantum group in the sense of Kustermans and Vaes. As a consequence, the modular autmorphism group of a unimodular quantum group can be expressed in terms of matrix coefficients. As an application, we determine the Duflo-Moore operator

A. Gordillo-Guerrero

We face the problem of phase transitions in diluted systems both from theoretical and numerical sides. We study the effects of quenched site-dilution in classical models (Heisenberg, Ising and Potts) in 2, 3, and 4 dimensions both by using the Renormalization Group and numerical simulations in the canonical and microcanonical ensembles. We propose and check

Alice Devillers, Michael Giudici, Cai Heng Li, Cheryl E. Praeger

We give a unified approach to analysing, for each positive integer $s$, a class of finite connected graphs that contains all the distance transitive graphs as well as the locally $s$-arc transitive graphs of diameter at least $s$. A graph is in the class if it is connected and if, for each vertex $v$, the subgroup of automorphisms fixing $v$ acts transitivel

Alice Devillers, Michael Giudici, Cai Heng Li, Geoffrey Pearce

A classification is given of rank 3 group actions which are quasiprimitive but not primitive. There are two infinite families and a finite number of individual imprimitive examples. When combined with earlier work of Bannai, Kantor, Liebler, Liebeck and Saxl, this yields a classification of all quasiprimitive rank 3 permutation groups. Our classification is

Erwin T. Lau, Daisuke Nagai, Andrey V. Kravtsov, Andrew R. Zentner

We present analysis of the three-dimensional shape of intracluster gas in clusters formed in cosmological simulations of the Lambda-CDM cosmology and compare it to the shape of dark matter distribution and the shape of the overall isopotential surfaces. We find that in simulations with radiative cooling, star formation and stellar feedback (CSF), intracluste

S. Raghu, A. Kapitulnik, S. A. Kivelson

Using an asymptotically exact weak coupling analysis of a multi-orbital Hubbard model of the electronic structure of \SRO, we show that the interplay between spin and charge fluctuations leads unequivocally to triplet pairing which originates in the quasi-one dimensional bands. The resulting superconducting state spontaneously breaks time-reversal symmetry a

Wang-Kong Tse, A. H. MacDonald

Topological insulators can exhibit strong magnetoelectric effects when their time-reversal symmetry is broken. In this Letter we consider the magneto-optical Kerr and Faraday effects of a topological insulator thin film weakly exchange-coupled to a ferromagnet. We find that its Faraday rotation has a universal value at low-frequencies, $θ_{\mathrm{F}} = \mat

Behrouz Khoshnevis, Wei Yu

This paper addresses the optimal design of limited-feedback downlink multi-user spatial multiplexing systems. A multiple-antenna base-station is assumed to serve multiple single-antenna users, who quantize and feed back their channel state information (CSI) through a shared rate-limited feedback channel. The optimization problem is cast in the form of minimi

Behrouz Khoshnevis, Wei Yu

This paper studies the design and optimization of a limited feedback single-user system with multiple-antenna transmitter and single-antenna receiver. The design problem is cast in form of the minimizing the average transmission power at the base station subject to the user&#39;s outage probability constraint. The optimization is over the user&#39;s channel

Anton H. Westveld, Peter D. Hoff

In this article we evaluate the statistical evidence that a population of students learn about the sub-game perfect Nash equilibrium of the centipede game via repeated play of the game. This is done by formulating a model in which a player&#39;s error in assessing the utility of decisions changes as they gain experience with the game. We first estimate param

A. P. Balachandran, Anosh Joseph, Pramod Padmanabhan

There are good reasons to suspect that spacetime at Planck scales is noncommutative. Typically this noncommutativity is controlled by fixed &#34;vectors&#34; or &#34;tensors&#34; with numerical entries. For the Moyal spacetime, it is the antisymmetric matrix $θ_{μν}$. In approaches enforcing Poincaré invariance, these deform or twist the method of (anti-)sym

Szu-Cheng Cheng, Shih-Da Jheng, T. F. Jiang

We have investigated the behavior and stability of a Wigner crystal of rotating dipolar fermions in two dimensions. Using an ansatz wave function for the ground state of rotating two-dimensional dipolar fermions, which occupy only partially the lowest Landau level, we study the correlation energy, elastic moduli and collective modes of Wigner crystals in the

Stephan Rachel, Karyn Le Hur

We investigate the Hubbard model on the honeycomb lattice with intrinsic spin orbit interactions as a paradigm for two-dimensional topological band insulators in the presence of interactions. Applying a combination of Hartree-Fock theory, slave-rotor techniques, and topological arguments, we show that the topological band insulating phase persists up to quit

Victor Galitski

We consider quantum dynamics of the order parameter in the discrete pairing model (Richardson model) in thermodynamic equilibrium. The integrable Richardson Hamiltonian is represented as a direct sum of Hamiltonians acting in different Hilbert spaces of single-particle and paired/empty states. This allows us to factorize the full thermodynamic partition func

Zhanybek Alpichshev, J. G. Analytis, J. -H. Chu, I. R. Fisher

Detailed study of the LDOS associated with the surface-state-band near a step-edge of the strong topological-insulator Bi2Te3, reveal a one-dimensional bound state that runs parallel to the stepedge and is bound to it at some characteristic distance. This bound state is clearly observed in the bulk gap region, while it becomes entangled with the oscillations

Antonio Rodriguez, Constantino Tsallis

As well known, cumulant expansion is an alternative way to moment expansion to fully characterize probability distributions provided all the moments exist. If this is not the case, the so called escort mean values (or q-moments) have been proposed to characterize probability densities with divergent moments [C. Tsallis et al, J. Math. Phys 50, 043303 (2009)]