February 2011 arXiv papers — page 4

M. Amin Khajehnejad, Juhwan Yoo, Animashree Anandkumar, Babak Hassibi

We introduce a new class of measurement matrices for compressed sensing, using low order summaries over binary sequences of a given length. We prove recovery guarantees for three reconstruction algorithms using the proposed measurements, including $\ell_1$ minimization and two combinatorial methods. In particular, one of the algorithms recovers $k$-sparse ve

Mikhail Gorchtein, Peng Guo, Adam P. Szczepaniak

We consider the electromagnetic and transition pion form factors. Using dispersion relations we simultaneously describe both the hadronic, time-like region and the asymptotic region of large energy-momentum transfer. For the latter we propose a novel mechanism of Regge fermion exchange. We find that hadronic contributions dominate form factors at all current

Mihail N. Kolountzakis

A set $Ω$, of Lebesgue measure 1, in the real line is called spectral if there is a set $Λ$ of real numbers such that the exponential functions $e_λ(x) = \exp(2πi λx)$ form a complete orthonormal system on $L^2(Ω)$. Such a set $Λ$ is called a spectrum of $Ω$. In this note we present a simplified proof of the fact that any spectrum $Λ$ of a set $Ω$ which is f

A. S. Trushechkin

In this report we discuss the organization of different levels of nature and the corresponding space-time structures by the consideration of a particular problem of time irreversibility. The fundamental time irreversibility problem consists in the following: how to reconcile the time-reversible microscopic dynamics and the irreversible macroscopic one. The r

Jonathan D. Beezley, Jan Mandel, Loren Cobb

We present a new type of the EnKF for data assimilation in spatial models that uses diagonal approximation of the state covariance in the wavelet space to achieve adaptive localization. The efficiency of the new method is demonstrated on an example.

Philippe Di Francesco, Rinat Kedem

We solve the quantum version of the $A_1$ $T$-system by use of quantum networks. The system is interpreted as a particular set of mutations of a suitable (infinite-rank) quantum cluster algebra, and Laurent positivity follows from our solution. As an application we re-derive the corresponding quantum network solution to the quantum $A_1$ $Q$-system and gener

Noel Brady, Dan Guralnik, Sang Rae Lee

We introduce the class of perturbed right-angled Artin groups. These are constructed by gluing Bieri double groups into standard right-angled Artin groups. As a first application of this construction we obtain families of CAT(0) groups containing finitely presented subgroups which are not of type $\mathrm{FP}_3$, and have exponential, or polynomial Dehn func

S. Boettcher

Ground states of Ising spin glasses on fully connected graphs are studied for a broadly distributed bond family. In particular, bonds $J$ distributed according to a Levy distribution P(J)\propto 1/|J|^{1+α}, |J|>1, are investigated for a range of powers α. The results are compared with those for the Sherrington-Kirkpatrick (SK) model, where bonds are Gaussia

P. Moskal

One of the basic motivations of the KLOE-2 and WASA-at-COSY experiments is the test of fundamental symmetries and the search for phenomena beyond the Standard Model in the hadronic and leptonic decays of ground-state mesons and in particular in decays of the $η$ meson. At COSY these mesons are produced in collisions of proton or deuteron beam with hydrogen o

Jonathan Yazinski

The 3x+1 function T is defined on the positive integers by $T(x) = \frac{3x+1}{2}$ for x odd and $T(x) = \frac{x}{2}$ for x even. The function T has a natural extension to the 2-adic integers, and there is a continuous function $Φ$ which conjugates T to the 2-adic shift map $σ$. Bernstein and Lagarias conjectured that -1 and 1/3 are the only odd fixed points

David Garfinkle

GGR News: GGR Program at the APS meeting in Anaheim, CA by David Garfinkle We hear that..., by David Garfinkle 100 years ago, by David Garfinkle Research Briefs: Endpoint of the Gregory-Laflamme Instability, by Gary Horowitz Conference Reports: Chandrasekhar Symposium, by David Garfinkle

Weinan E, Jianfeng Lu

The electronic structure (electron charges and spins) of a perfect crystal under external magnetic field is analyzed using the spin-polarized Thomas-Fermi-Dirac-von Weizsacker model. An extension of the classical Cauchy-Born rule for crystal lattices is established for the electronic structure under sharp stability conditions on charge density wave and spin

Carlos Hoppen, Yoshiharu Kohayakawa, Hanno Lefmann

For fixed positive integers $r, k$ and $\ell$ with $1 \leq \ell < r$ and an $r$-uniform hypergraph $H$, let $κ(H, k,\ell)$ denote the number of $k$-colorings of the set of hyperedges of $H$ for which any two hyperedges in the same color class intersect in at least $\ell$ elements. Consider the function $\KC(n,r,k,\ell)=\max_{H\in{\mathcal H}_{n}} κ(H, k,\ell

Katsiaryna Krupchyk, Matti Lassas, Gunther Uhlmann

We show that a first order perturbation $A(x)\cdot D+q(x)$ of the polyharmonic operator $(-Δ)^m$, $m\ge 2$, can be determined uniquely from the set of the Cauchy data for the perturbed polyharmonic operator on a bounded domain in $R^n$, $n\ge 3$. Notice that the corresponding result does not hold in general when $m=1$.

Tracy E. Clarke, Torsten Enßlin, Alexis Finoguenov, Huib Intema

Abell 2256 is a rich, nearby (z=0.0594) galaxy cluster that has significant evidence of merger activity. We present new radio and X-ray observations of this system. The low-frequency radio images trace the diffuse synchrotron emission of the Mpc-scale radio halo and relics as well as a number of recently discovered, more compact, steep spectrum sources. The

Mohammed Abderrahman Ebde, Hatem Zaag

We consider a nonlinear heat equation with a gradient term. We construct a blow-up solution for this equation with a prescribed blow-up profile. For that, we translate the question in selfsimilar variables and reduce the problem to a finite dimensional one. We then solve the finite dimensional problem using index theory. The interpretation of the finite dime

Indu Shakya, Falah H. Ali, Elias Stipidis

User cooperation is a well-known approach to achieve diversity without multiple antennas, however at the cost of inevitable loss of rate mostly due to the need of additional channels for relaying. A new collaborative diversity scheme is proposed here for multiple access fading channels to attain full rate with near maximum diversity. This is achieved by allo

Giovanni Gaiffi, Matteo Serventi

In this paper we focus on maximal complex De Concini-Procesi models associated to root arrangements of types A, B, C, D and we compute inductive formulas for their Poincare&#39; series.

J. Knolle, I. Eremin, R. Moessner

We present a general theory of multiorbital spin waves in magnetically ordered metallic systems. Motivated by the itinerant magnetism of iron-based superconductors, we compare the magnetic excitations for two different scenarios: when the magnetic order either sets in on the on-site orbital level; or when it appears as an electron-hole pairing between differ

P. Bicudo, M. Cardoso, N. Cardoso

We study the QCD phase diagram, in particular we study the critical points of the two main QCD phase transitions, confinement and chiral symmetry breaking. Confinement drives chiral symmetry breaking, and, due to the finite quark mass, at small density both transitions are a crossover, while they are a first or second order phase transition in large density.

Paolo Ciarcelluti

Mirror matter is a stable self-collisional dark matter candidate. If parity is a conserved unbroken symmetry of nature, there could exist a parallel hidden (mirror) sector of the Universe composed of particles with the same masses and obeying the same physical laws as our (visible) sector, except for the opposite handedness of weak interactions. The two sect

Steven Widmer

Given a countable set X (usually taken to be N or Z), an infinite permutation $π$ of X is a linear ordering $<_π$ of X. This paper investigates the combinatorial complexity of infinite permutations on N associated with the image of uniformly recurrent aperiodic binary words under the letter doubling map. An upper bound for the complexity is found for general

A. N. Morozovska, E. A. Eliseev, G. S. Svechnikov, S. V. Kalinin

Nanoscale enables a broad range of electromechanical coupling mechanisms that are forbidden or negligible in the materials. We conduct a theoretical study of the electromechanical response of thin paraelectric films with mobile vacancies (or ions) paradigmatic for capacitor-type measurements in X-ray scattering, piezoresponse force microscopy (PFM), and elec

Mikhail Martynov, Olga Rozanova

We present an explicit hedging strategy, which enables to prove arbitrageness of market incorporating at least two assets depending on the same random factor. The implied Black-Scholes volatility, computed taking into account the form of the graph of the option price, related to our strategy, demonstrates the &#34;skewness&#34; inherent to the observational

Jean-Luc Fouquet, Jean-Marie Vanherpe

In a graph $G$ of maximum degree 3, let $γ(G)$ denote the largest fraction of edges that can be 3 edge-coloured. Rizzi \cite{Riz09} showed that $γ(G) \geq 1-\frac{2\strut}{\strut 3 g_{odd}(G)}$ where $g_{odd}(G)$ is the odd girth of $G$, when $G$ is triangle-free. In \cite{FouVan10a} we extended that result to graph with maximum degree 3. We show here that $

Anna Eyal, Emil Polturak

We report studies of solid helium contained inside a torsional oscillator, at temperatures between 1.07K and 1.87K. We grew single crystals inside the oscillator using commercially pure $^4$He and $^3$He-$^4$He mixtures containing 100 ppm $^3$He. Crystals were grown at constant temperature and pressure on the melting curve. At the end of the growth, the crys

Jens Erler

Details are provided how GAPP evaluates the strong coupling constant from Z and tau decays and the corresponding uncertainties.

Abdullo Tabarov

The article is a continuation of the author&#39;s work &#34;Linear quasigroups. I&#34; and devoted to linear quasigroups and some of their generalizations. In the second part identities and linearity of quasigroups are investigated, in particular, the approach of finding quasigroup identities from some variety of loops is presented. Besides that we give shor

O. Crauste, C. A. Marrache-Kikuchi, L. Berge, S. Collin

We report on the superconducting properties of amorphous NbxSi1-x thin films. The normal-state resistance and critical temperatures can be separately adjusted to suit the desired application. Notably, the relatively low electron-phonon coupling of these films makes them good candidates for an &#34;all electron bolometer&#34; for Cosmological Microwave Backgr

Abdullo Tabarov

The article is devoted to linear quasigroups and some of their generalizations. In the first part main definitions and notions of the theory of quasigroups are given. In the second part some elementary properties of linear quasigroups and their generalizations are presented. Finally in the third part endomorphisms and endotopies of linear quasigroups and the

Wojciech Wislicki

Prospective presentation is given for the experimental program of the KLOE-2 Collaboration, to be performed using the DA$Φ$NE $e^+e^-$ collider upgraded in luminosity. Data with the total luminosity of 25 fb$^{-1}$ are aimed to be collected in 3 years. Major modifications of the accelerator and the spectrometer are described. The KLOE-2 physics program conta

Richard J. Mathar

The phase structure function accumulated by two parallel rays after transmission through a layer of turbulent air is best known by a proportionality to the 5/3rd power of the lateral distance in the aperture, derived from an isotropic Kolmogorov spectrum of the refractive index. For a von-Karman spectrum of the refractive index, a dependence involving a modi

Sean Z. W. Lip

Various methods have been proposed in the literature to determine an optimal partitioning of the set of actors in a network into core and periphery subsets. However, these methods either work only for relatively small input sizes, or do not guarantee an optimal answer. In this paper, we propose a new algorithm to solve this problem. This algorithm is efficie

Leo Lahti

Understanding functional organization of genetic information is a major challenge in modern biology. Following the initial publication of the human genome sequence in 2001, advances in high-throughput measurement technologies and efficient sharing of research material through community databases have opened up new views to the study of living organisms and t

I. M. Sokolov, D. V. Kupriyanov, M. D. Havey

We consider the influence of a resonant control field on weak localization of light in ultracold atomic ensembles. Both steady-state and pulsed light excitation are considered. We show that the presence of a control field essentially changes the type of interference effects which occur under conditions of multiple scattering. For example, for some scattering

S. Gapochenko, V. Belozertseva, H. Khlyap, A. Mamalui

Raman spectra of GexAsySe100-x-y (0 < x < 30; 10 < y < 40) glasses have been studied at room temperature. Three sets of samples were investigated; it was revealed that they are qualitatively differing by shape of their spectra. The structure model was proposed for glasses of each set. The selection of the glasses on the sets with the same structure type can

Wei Chen, A. V. Andreev, L. I. Glazman

In an armchair carbon nanotube pn junction the p- and n- regions are separated by a region of a Mott insulator, which can backscatter electrons only in pairs. We predict a quantum-critical behavior in such a pn junction. Depending on the junction&#39;s built-in electric field E, its conductance G scales either to zero or to the ideal value G=4e^2/h as the te

D. Kumar, H. J. Haubold

The major problem in the cosmological nucleosynthesis is the evaluation of the reaction rate. The present scenario is that the standard thermonuclear function in the Maxwell-Boltzmann form is evaluated by using various techniques. The Maxwell-Boltzmannian approach to nuclear reaction rate theory is extended to cover Tsallis statistics (Tsallis, 1988) and mor

Supravat Dey, Dibyendu Das, R. Rajesh

We propose two lattice models in one dimension, with stochastically hopping particles which aggregate on contact. The hops are guided by &#34;velocity rates&#34; which themselves evolve according to the rules of ballistic aggregation as in a sticky gas in continuum. Our lattice models have both velocity and density fields and an appropriate real time evoluti

E. A. Bruevich, G. V. Yakunina

The monthly average values of the main solar activity indices such as Wolf numbers (W), 10,7 cm radio flux (F10,7), 0,1-0,8 nm background, total solar irradiance and Mg II UV-index (280 nm core to wing ratio) were studied for 23 activity cycle. The correlation coefficients of linear regression for main solar activity indices versus F10,7 were analyzed for ev

Jocelyne Bion-Nadal, Giulia Di Nunno

In an $L_\infty$-framework, we present a few extension theorems for linear operators. We focus the attention on majorant preserving and sandwich preserving types of extensions. These results are then applied to the study of price systems derived by a reasonable restriction of the class of equivalent martingale measures applicable. First we consider equivalen

Linyuan Lu, Weiping Liu

Recommender systems have shown great potential to address information overload problem, namely to help users in finding interesting and relevant objects within a huge information space. Some physical dynamics, including heat conduction process and mass or energy diffusion on networks, have recently found applications in personalized recommendation. Most of t

H. J. Haubold, A. M. Mathai, R. K. Saxena

This paper is a continuation of our earlier paper in which we have derived the solution of an unified fractional reaction-diffusion equation associated with the Caputo derivative as the time-derivative and the Riesz-Feller fractional derivative as the space-derivative. In this paper, we consider an unified reaction-diffusion equation with Riemann-Liouville f

M. V. Hermenegildo, F. Bueno, M. Carro, P. López-García

We provide an overall description of the Ciao multiparadigm programming system emphasizing some of the novel aspects and motivations behind its design and implementation. An important aspect of Ciao is that, in addition to supporting logic programming (and, in particular, Prolog), it provides the programmer with a large number of useful features from differe

Angel Ballesteros, Alberto Enciso, Francisco J. Herranz, Orlando Ragnisco

The full spectrum and eigenfunctions of the quantum version of a nonlinear oscillator defined on an N-dimensional space with nonconstant curvature are rigorously found. Since the underlying curved space generates a position-dependent kinetic energy, three different quantization prescriptions are worked out by imposing that the maximal superintegrability of t

Hassen Aydi

We present coincidence and common fixed point results of selfmappings satisfying a contraction type in partially ordered metric spaces. As an application, we give an existence theorem for a common solution of integral equations.

M. S. Moslehian, R. Nakamoto, Y. Seo

We present a Diaz--Metcalf type operator inequality as a reverse Cauchy-Schwarz inequality and then apply it to get the operator versions of Pólya-Szegö&#39;s, Greub-Rheinboldt&#39;s, Kantorovich&#39;s, Shisha-Mond&#39;s, Schweitzer&#39;s, Cassels&#39; and Klamkin-McLenaghan&#39;s inequalities via a unified approach. We also give some operator Grüss type ine

Rachid Belfadli, Khalifa Es-Sebaiy, Youssef Ouknine

We consider the parameter estimation problem for the non-ergodic fractional Ornstein-Uhlenbeck process defined as $dX_t=θX_tdt+dB_t,\ t\geq0$, with a parameter $θ>0$, where $B$ is a fractional Brownian motion of Hurst index $H\in(1/2,1)$. We study the consistency and the asymptotic distributions of the least squares estimator $\hatθ_t$ of $θ$ based on the ob

Maksim D. Tomchenko

We propose a possible microscopic explanation of the exhaustion of ρ_s of helium-II on the wall at T>T_{c} = 0.5 - 1 K and predict a possibility of the existence in He-II of the &#34;dry&#34; friction at T < T_{c}. Both of the effects connect with that the energy of the 2D-rotons is 2K less then the energy of 3D-rotons, so the wall is a potential well for th

David Ruelle

Nonequilibrium statistical mechanics close to equilibrium is a physically satisfactory theory centered on the linear response formula of Green-Kubo. This formula results from a formal first order perturbation calculation without rigorous justification. A rigorous derivation of Fourier&#39;s law for heat conduction from the laws of mechanics remains thus a ma

Ealeal Bear, Noam Soker

We study the evaporation of planets orbiting close to hot (extreme) horizontal branch (EHB) stars. These planets survived the common envelope phase inside the envelope of the reg giant star progenitor. We find that Jupiter-like planets orbiting within 10Ro from an EHB star suffers a non-negligible mass-loss during their 10^8 yr evolution on the horizontal br

Jaehak Lee, Hai-Woong Lee, Mark Hillery

We examine a search on a graph among a number of different kinds of objects (vertices), one of which we want to find. In a standard graph search, all of the vertices are the same, except for one, the marked vertex, and that is the one we wish to find. We examine the case in which the unmarked vertices can be of different types, so the background against whic

Amira Ghorbel

Let $G$ be a connected, simply connected one-parameter metabelian nilpotent Lie group, that means, the corresponding Lie algebra has a one-codimensional abelian subalgebra. In this article we show that $G$ contains a discrete cocompact subgroup. Given a discrete cocompact subgroup $Γ$ of $G$, we define the quasi-regular representation $τ= {\rm ind}_Γ^G 1$ of

Arindam Pal

We study the problem of finding minimum multicuts for an undirected planar graph, where all the terminal vertices are on the boundary of the outer face. This is known as an Okamura-Seymour instance. We show that for such an instance, the minimum multicut problem can be reduced to the minimum-cost Steiner forest problem on a suitably defined dual graph. The m

H. Q. Yuan, L. Jiao, F. F. Balakirev, J. Singleton

Variant approaches, either based on the Fermi surface nesting or started from the proximity to a Mott-insulator, were proposed to elucidate the physics in iron pnictides, but no consensus has been reached. A fundamental problem concerns the nature of their 3d electrons. Here we report the magnetoresistivity (ρ_xx) and the Hall resistivity (ρ_xy) of Ba(Fe1-xC

Shu Tanaka, Ryo Tamura, Naoki Kawashima

We investigate the nature of the phase transition of the ferromagnetic Potts model with invisible states. The ferromagnetic Potts model with invisible states can be regarded as straightforward extension of the standard ferromagnetic Potts model. The invisible states contribute the entropy, however they do not affect the internal energy. They also do not chan

Arnab Das, Jacopo Sabbatini, Wojciech H. Zurek

We simulate Bose-Einstein condensation (BEC) in a ring employing stochastic Gross-Pitaevskii equation and show that cooling through the critical temperature can generate spontaneous quantized circulation around the ring of the newborn condensate. Dispersion of the resulting winding numbers follows scaling law predicted by the Kibble-Zurek mechanism (KZM). De

J. -N. Zhang, R. -Z. Qiu, L. He, S. Yi

We investigate the dynamical properties of a trapped finite-temperature normal Fermi gas with dipole-dipole interaction. For the free expansion dynamics, we show that the expanded gas always becomes stretched along the direction of the dipole moment. In addition, we present the temperature and interaction dependences of the asymptotical aspect ratio. We furt

Mary V. Ashley, Tanya Y. Berger-Wolf, Wanpracha Chaovalitwongse, Bhaskar DasGupta

In an implicit combinatorial optimization problem, the constraints are not enumerated explicitly but rather stated implicitly through equations, other constraints or auxiliary algorithms. An important subclass of such problems is the implicit set cover (or, equivalently, hitting set) problem in which the sets are not given explicitly but rather defined impli

Kevin Stovall, Teviet Creighton, Richard H. Price, Fredrick A. Jenet

According to some models, there may be a significant population of radio pulsars in the Galactic center. In principle, a beam from one of these pulsars could pass close to the supermassive black hole (SMBH) at the center, be deflected, and be detected by Earth telescopes. Such a configuration would be an unprecedented probe of the properties of spacetime in

Li De-sheng, Tian Feng-Ge, Chen Gang

In this thesis a set of methods identifying minijet from final state particles in the relativistic heavy ion collision events is established and the parameter dependence has been investigated in Au+Au collisions at $\sqrt s= 200$GeV using a multiphase transport model (AMPT). It is found that the number of minijets reduces with the increasing of collision par

Hua Wang

Let $L=-Δ+V$ be a Schrödinger operator acting on $L^2(\mathbb R^n)$, $n\ge1$, where $V\not\equiv 0$ is a nonnegative locally integrable function on $\mathbb R^n$. In this article, we will introduce weighted Hardy spaces $H^p_L(w)$ associated with $L$ by means of the area integral function and study their atomic decomposition theory. We also show that the Rie

Donald W. Barnes

I describe the lattice of subalgebras of a one-generator Leibniz algebra. Using this, I show that, apart from one special case, a lattice isomorphism between Leibniz algebras L, L&#39; maps the Leibniz kernel of L to that of L&#39;.

Michael Burr, Sung Woo Choi, Ben Galehouse, Chee Yap

Given a real valued function f(X,Y), a box region B_0 in R^2 and a positive epsilon, we want to compute an epsilon-isotopic polygonal approximation to the restriction of the curve S=f^{-1}(0)={p in R^2: f(p)=0} to B_0. We focus on subdivision algorithms because of their adaptive complexity and ease of implementation. Plantinga and Vegter gave a numerical sub

T. M. Aliev, K. Azizi, M. Savci

The strong coupling constants among members of the heavy spin--3/2 baryons containing single heavy quark with light pseudoscalar mesons are calculated in the framework of the light cone QCD sum rules. Using symmetry arguments, the structure independent relations among different correlation functions are obtained. It is shown that all possible transitions can

Y. Liu, Oleg A. Tretiakov, Ar. Abanov

We study current-induced domain-wall dynamics in a thin ferromagnetic nanowire. The domain-wall dynamics is described by simple equations with four parameters. We propose the procedure to determine these parameters by all-electric measurements of the time-dependent voltage induced by the domain-wall motion. We provide an analytical expression for the time va

Xiaolei Zhang

It is argued that human consciousness is likely to have emerged during the self-consistent evolution of the physical universe, through the gradual accumulation of biological entities&#39; ability to tap into the intrinsic non-deterministic potentiality in the global nonequilibrium phase transitions occurring continually in the quantum universe. Due to the fa

J. Doyne Farmer, Austin Gerig, Fabrizio Lillo, Henri Waelbroeck

We develop a theory for the market impact of large trading orders, which we call metaorders because they are typically split into small pieces and executed incrementally. Market impact is empirically observed to be a concave function of metaorder size, i.e., the impact per share of large metaorders is smaller than that of small metaorders. We formulate a sty

Leandro Arosio

We prove that, on a complete hyperbolic domain D\subset C^q, any Loewner PDE associated with a Herglotz vector field of the form H(z,t)=A(z)+O(|z|^2), where the eigenvalues of A have strictly negative real part, admits a solution given by a family of univalent mappings (f_t: D\to C^q) such that the union of the images f_t(D) is the whole C^q. If no real reso

Miroslav Ćirić, Jelena Ignjatović, Nada Damljanović, Milan Bašić

Bisimulations have been widely used in many areas of computer science to model equivalence between various systems, and to reduce the number of states of these systems, whereas uniform fuzzy relations have recently been introduced as a means to model the fuzzy equivalence between elements of two possible different sets. Here we use the conjunction of these t

Jan Lellmann, Christoph Schnörr

We study convex relaxations of the image labeling problem on a continuous domain with regularizers based on metric interaction potentials. The generic framework ensures existence of minimizers and covers a wide range of relaxations of the originally combinatorial problem. We focus on two specific relaxations that differ in flexibility and simplicity -- one c

N. Sedlmayr, S. Eggert, J. Sirker

We study the properties of interacting electrons in a one-dimensional conduction band coupled to bulk non-collinear ferromagnetic order. The specific form of non-collinearity we consider is that of an extended domain wall. The presence of ferromagnetic order breaks spin-charge separation and the domain wall introduces a spin-dependent scatterer active over t

Lev A. Borisov, Ralph M. Kaufmann

We conjecture a description of the vertex (chiral) algebras of the (0,2) nonlinear sigma models on smooth quintic threefolds. We provide evidence in favor of the conjecture by connecting our algebras to the cohomology of a twisted chiral de Rham sheaf. We discuss CY/LG correspondence in this setting.

Ashot Melikyan, M. R. Norman

We derive and analyze an effective Ginzburg-Landau (GL) functional for a charge density wave (CDW) for a model of electrons on a tight binding square lattice with density-density interactions. We show, using realistic electronic dispersions for the cuprates, that for the simplest GL theory, the preferred symmetry is of the uni-directional (stripe) type, but

Pinar Heggernes, Pim van &#39;t Hof, Daniel Lokshtanov, Christophe Paul

We initiate the study of the Bipartite Contraction problem from the perspective of parameterized complexity. In this problem we are given a graph $G$ and an integer $k$, and the task is to determine whether we can obtain a bipartite graph from $G$ by a sequence of at most $k$ edge contractions. Our main result is an $f(k) n^{O(1)}$ time algorithm for Biparti

J. L. Chkareuli, C. D. Froggatt, H. B. Nielsen

An arbitrary local theory of a symmetric two-tensor field $H_{μν}$ in Minkowski spacetime is considered, in which the equations of motion are required to be compatible with a nonlinear length-fixing constraint $H_{μν}^{2}=\pm M^{2}$ leading to spontaneous Lorentz invariance violation, SLIV ($M$ is the proposed scale for SLIV). Allowing the parameters in the

Eugenio Bianchi, Hal M. Haggard

A major challenge for any theory of quantum gravity is to quantize general relativity while retaining some part of its geometrical character. We present new evidence for the idea that this can be achieved by directly quantizing space itself. We compute the Bohr-Sommerfeld volume spectrum of a tetrahedron and show that it reproduces the quantization of a grai

Jarosław Grytczuk, Jakub Kozik, Marcin Witkowski

A sequence $S=s_{1}s_{2}..._{n}$ is \emph{nonrepetitive} if no two adjacent blocks of $S$ are identical. In 1906 Thue proved that there exist arbitrarily long nonrepetitive sequences over 3-element set of symbols. We study a generalization of nonrepetitive sequences involving arithmetic progressions. We prove that for every $k\geqslant 1$ and every $c\geqsla

Nicholas Mastronarde, Francesco Verde, Donatella Darsena, Anna Scaglione

We investigate the impact of cooperative relaying on uplink and downlink multi-user (MU) wireless video transmissions. The objective is to maximize the long-term sum of utilities across the video terminals in a decentralized fashion, by jointly optimizing the packet scheduling, the resource allocation, and the cooperation decisions, under the assumption that

Nelson Faustino, Guangbin Ren

We introduce the umbral calculus formalism for hypercomplex variables starting from the fact that the algebra of multivariate polynomials $\BR[\underline{x}]$ shall be described in terms of the generators of the Weyl-Heisenberg algebra. The extension of $\BR[\underline{x}]$ to the algebra of Clifford-valued polynomials $\mathcal{P}$ gives rise to an algebra

Tanbir Ahmed, Oliver Kullmann, Hunter Snevily

We present results and conjectures on the van der Waerden numbers w(2;3,t) and on the new palindromic van der Waerden numbers pdw(2;3,t). We have computed the new number w(2;3,19) = 349, and we provide lower bounds for 20 <= t <= 39, where for t <= 30 we conjecture these lower bounds to be exact. The lower bounds for 24 <= t <= 30 refute the conjecture that

Valerio Capraro, Florin Radulescu

Let $M$ be a $II_1$-factor with trace $τ$, the linear subspaces of $L^2(M,τ)$ are not just common Hilbert spaces, but they have additional structure. We introduce the notion of a cyclic linear space by taking those properties as axioms. In Sec.2 we formulate the following problem: &#34;does every cyclic Hilbert space embed into $L^2(M,τ)$, for some $M$?&#34;

CMS Collaboration

A measurement of WW production in pp collisions at sqrt(s) = 7 TeV and a search for the Higgs boson are reported. The WW candidates are selected in events with two leptons, either electrons or muons. The measurement is performed using LHC data recorded with the CMS detector, corresponding to an integrated luminosity of 36 inverse picobarns. The pp to WW cros

Vaughn Climenhaga

Most results in multifractal analysis are obtained using either a thermodynamic approach based on existence and uniqueness of equilibrium states or a saturation approach based on some version of the specification property. A general framework incorporating the most important multifractal spectra was introduced by Barreira and Saussol, who used the thermodyna

Xian-Wei Kang, Hai-Bo Li, Gong-Ru Lu

The semileptonic $D_{l4}$ decay including $D\to Kπlν$ and $D\to ππlν$ have been extensively studied. In these references, the form factors and differential decay rate are explicitly stated. However, we would like to stress that in these papers the final state interactions are often overlooked, i.e. rescattering effect of the pseudoscalars produced by $D_{l4}

James Ira Thorpe, Peiman Maghami, Jeffrey Livas

Arm locking is a technique that has been proposed for reducing laser frequency fluctuations in the Laser Interferometer Space Antenna (LISA), a gravitational-wave observatory sensitive in the milliHertz frequency band. Arm locking takes advantage of the geometric stability of the triangular constellation of three spacecraft that comprise LISA to provide a fr

Bernard F. Schutz

This paper develops a general framework for studying the effectiveness of networks of interferometric gravitational wave detectors and then uses it to show that enlarging the existing LIGO-VIRGO network with one or more planned or proposed detectors in Japan (LCGT), Australia, and India brings major benefits, including much larger detection rate increases th

Barbara Betz, Miklos Gyulassy, Giorgio Torrieri

Second Fourier harmonics of jet quenching have been thoroughly explored in the literature and shown to be sensitive to the underlying jet path-length dependence of energy loss and the differences between the mean eccentricity predicted by Glauber and CGC/KLN models of initial conditions. We compute the jet path-length dependence of energy-loss for higher azi

Yevgeniy Dodis, Xin Li, Trevor D. Wooley, David Zuckerman

In studying how to communicate over a public channel with an active adversary, Dodis and Wichs introduced the notion of a non-malleable extractor. A non-malleable extractor dramatically strengthens the notion of a strong extractor. A strong extractor takes two inputs, a weakly-random x and a uniformly random seed y, and outputs a string which appears uniform

R. J. Mondragon, S. Zhou

In complex networks it is common to model a network or generate a surrogate network based on the conservation of the network&#39;s degree distribution. We provide an alternative network model based on the conservation of connection density within a set of nodes. This density is measure by the rich-club coefficient. We present a method to generate surrogates

Marcin Piatek

The so-called Poghossian identities connecting the toric and spherical blocks, the AGT relation on the torus and the Nekrasov-Shatashvili formula for the elliptic Calogero-Moser Yang&#39;s (eCMY) functional are used to derive certain expressions for the classical 4-point block on the sphere. The main motivation for this line of research is the longstanding o

Yang Huang

In 1989, Y. Eliashberg proved that two overtwisted contact structures on a closed oriented 3-manifold are isotopic if and only if they are homotopic as 2-plane fields. We provide an alternative proof of this theorem using the convex surface theory and bypasses.

Chris Parker, Gernot Stroth

We identify the groups $PSU_6(2)$, $PSU_6(2):2$, $PSU_6(2):3$ and $Aut(PSU_6(2))$ from the structure of the centralizer of an element of order 3.

Anna Klimova, Tamás Rudas, Adrian Dobra

The paper considers general multiplicative models for complete and incomplete contingency tables that generalize log-linear and several other models and are entirely coordinate free. Sufficient conditions of the existence of maximum likelihood estimates under these models are given, and it is shown that the usual equivalence between multinomial and Poisson l

Joost J. Joosten, Fernando Soler-Toscano, Hector Zenil

The aim of this paper is to undertake an experimental investigation of the trade-offs between program-size and time computational complexity. The investigation includes an exhaustive exploration and systematic study of the functions computed by the set of all 2-color Turing machines with 2, 3 and 4 states--denoted by (n,2) with n the number of states--with p

Martin Slota, João Leite

Rules in logic programming encode information about mutual interdependencies between literals that is not captured by any of the commonly used semantics. This information becomes essential as soon as a program needs to be modified or further manipulated. We argue that, in these cases, a program should not be viewed solely as the set of its models. Instead, i

Jiadong Zang, Maxim Mostovoy, Jung Hoon Han, Naoto Nagaosa

We study the collective dynamics of the Skyrmion crystal (SkX) in thin films of ferromagnetic metals resulting from the nontrivial Skyrmion topology. We show that the current-driven motion of the crystal reduces the topological Hall effect and the Skyrmion trajectories bend away from the direction of the electric current (the Skyrmion Hall effect). We find a

Hiroshi Isozaki, Yaroslav Kurylev

We study the spectral theory and inverse problem on asymptotically hyperbolic manifolds. The main subjects are as follows: (1)Location of the essential spectrum. (2)Absence of eigenvalues embedded in the continuous spectrum. (3)Limiting absorption principle for the resolvent and the absolute continuity of the continuous spectrum. (4)Construction of the gener

Zhou Zhang, Hai Jiang

In this paper, the problem of distributed opportunistic channel access in wireless relaying is investigated. A relay network with multiple source-destination pairs and multiple relays is considered. All the source nodes contend through a random access procedure. A winner source node may give up its transmission opportunity if its link quality is poor. In thi

Amruta Joshi, Junghoo Cho, Dragomir Radev, Ahmed Hassan

Tag-based retrieval of multimedia content is a difficult problem, not only because of the shorter length of tags associated with images and videos, but also due to mismatch in the terminologies used by searcher and content creator. To alleviate this problem, we propose a simple concept-driven probabilistic model for improving text-based rich-media search. Wh