April 2013 arXiv papers — page 65

Denis Berthier

Pattern-Based Constraint Satisfaction and Logic Puzzles develops a pure logic, pattern-based perspective of solving the finite Constraint Satisfaction Problem (CSP), with emphasis on finding the "simplest" solution. Different ways of reasoning with the constraints are formalised by various families of "resolution rules", each of them carrying

Xiaoming Chen, Hsiao-Hwa Chen

In this work, we consider a multi-antenna cognitive ad hoc network (CAHNet) with heterogeneous delay requirements. To fulfill the interference and delay constraints simultaneously, we propose to perform adaptive zero-forcing beamforming (ZFBF) at cognitive transmitters according to interference channel state information (CSI). To assist the CAHNet to obtain

Natalia V. Pavlova, Petr N. Vabishchevich, Maria V. Vasilyeva

Temperature stabilization of oil and gas wells is used to ensure stability and prevent deformation of a subgrade estuary zone. In this work, we consider the numerical simulation of thermal stabilization using vertical seasonal freezing columns. A mathematical model of such problems is described by a time-dependent temperature equation with phase transitions

Michel Destrade, YiBin Fu

The surface-impedance matrix method is used to study interfacial waves polarized in a plane of symmetry of anisotropic elastic materials. Although the corresponding Stroh polynomial is a quartic, it turns out to be analytically solvable in quite a simple manner. A specific application of the result concerns the calculation of the speed of a Stoneley wave, po

A. A. Prokofiev, A. N. Poddubny, I. N. Yassievich

The decay of the optical phonon into the two phonons of smaller energy is calculated for Si nanocrystals. The rate of the process is in the range of 1 to 10 ps. Such anharmonic phonon decay may control the energy relaxation rate of excited carriers in Si/SiO$_2$ nanocrystals. Relevance of the phonon decay to the experimentally observed hot carrier photolumin

Carlos Lizama, Pedro J. Miana, Rodrigo Ponce, Luis Sánchez-Lajusticia

For $β>0$ and $p\ge 1$, the generalized Cesàro operator $$ \mathcal{C}_βf(t):=\fracβ{t^β}\int_0^t (t-s)^{β-1}f(s)ds $$ and its companion operator $\mathcal{C}_β^*$ defined on Sobolev spaces $\mathcal{T}_p^{(α)}(t^α)$ and $\mathcal{T}_p^{(α)}(| t|^α)$ (where $α\ge 0$ is the fractional order of derivation and are embedded in $L^p(\RR^+)$ and $L^p(\RR)$ respect

M. Majumder, K. Ghoshray, A. Ghoshray, A. Pal

75As and 31P NMR studies are performed in PrCoAsO and NdCoPO respectively. The Knight shift data in PrCoAsO indicate the presence of an antiferromagnetic interaction between the 4f moments along the c axis in the ferromagnetic state of Co 3d moments. We propose a possible spin structure in this system. The 75As quadrupolar coupling constant, $ν_Q$ increases

Jeffrey A. Blackburne, Christopher S. Kochanek, Bin Chen, Xinyu Dai

The gravitationally lensed quasar HE 1104-1805 has been observed at a variety of wavelengths ranging from the mid-infrared to X-ray for nearly 20 years. We combine flux ratios from the literature, including recent Chandra data, with new observations from the SMARTS telescope and HST, and use them to investigate the spatial structure of the central regions us

A. Annadi, Z. Huang, K. Gopinadhan, X. Renshaw Wang

The confinement of the two dimensional electron gas (2DEG), preferential occupancy of the Ti 3d orbital and strong spin-orbit coupling at the LaAlO$_3$/SrTiO$_3$ interface play a significant role in its emerging properties. Here we report a fourfold oscillation in the anisotropic magneto resistance (AMR) and the observation of planar Hall effect (PHE) at the

Archana Soam, G. Maheswar, H. C. Bhatt, Chang Won Lee

We present results of our $R-$band polarimetry of a cometary globule, LBN 437 (Gal96-15, $\ell$ $=$ 96$\degree$, \textit{b} $=-15\degree$), to study magnetic field geometry of the cloud. We estimated a distance of $360\pm65$ pc to LBN 437 (also one additional cloud, CB 238) using near-IR photometric method. Foreground contribution to the observed polarisatio

Yue Sun, Toshihiro Taen, Yuji Tsuchiya, Qingping Ding

We reported a controllable way of removing excess Fe in Fe1+yTe0.6Se0.4 by annealing in a fixed amount of O2. Compared with the weak superconductivity induced by dilute acids, O2 annealing can successfully induce bulk superconductivity. Proper O2 annealing changes the temperature dependence of resistivity at low temperatures from semiconducting to metallic,

Francis Valiquette

Given a Lie pseudo-group action, an equivariant moving frame exists in the neighborhood of a submanifold jet provided the action is free and regular. For local equivalence problems the freeness requirement cannot always be satisfied and in this paper we show that, with the appropriate modifications and assumptions, the equivariant moving frame constructions

Harshan Vasudevan Nampoori

Ferroelectrics have shown potential as a promising alternative material for future photovoltaic applications. Observance of high open circuit voltages in ferroelectric thin films, have generated considerable interest in the field of ferroelectric photovoltaic in recent years. The field of ferroelectric photovoltaic is evolving and not yet completely understo

Melek Tendurus, Atilim Gunes Baydin, Marieke A. Eleveld, Alison J. Gilbert

There are many studies dealing with the protection or restoration of wetlands and the sustainable economic growth of cities as separate subjects. This study investigates the conflict between the two in an area where city growth is threatening a protected wetland area. We develop a stochastic cellular automaton model for urban growth and apply it to the Vecht

Mario Mulansky

We present different techniques to numerically solve the equations of motion for the widely studied Discrete Nonlinear Schroedinger equation (DNLS). Being a Hamiltonian system, the DNLS requires symplectic routines for an efficient numerical treatment. Here, we introduce different such schemes in detail and compare their performance and accuracy by extensive

Su Do Yi, Beom Jun Kim, Petter Minnhagen

An allometric height-mass exponent $γ$ gives an approximative power-law relation $< M> \propto H^γ$ between the average mass $< M>$ and the height $H$, for a sample of individuals. The individuals in the present study are humans but could be any biological organism. The sampling can be for a specific age of the individuals or for an age-interval. The body-ma

Rebecca C. Steorts, Malay Ghosh

We consider benchmarked empirical Bayes (EB) estimators under the basic area-level model of Fay and Herriot while requiring the standard benchmarking constraint. In this paper we determine the excess mean squared error (MSE) from constraining the estimates through benchmarking. We show that the increase due to benchmarking is O(m^{-1}), where m is the number

Xiaolin Gong, Shuzhen Yang

This paper introduces a new distribution to improve tail risk modeling. Based on the classical normal distribution, we define a new distribution by a series of heat equations. Then, we use market data to verify our model.

F. E. S. Steinhoff, M. C. de Oliveira, J. Sperling, W. Vogel

We introduce a class of bipartite entangled continuous variable states that are positive under partial transposition operation, i.e., PPT bound entangled. These states are based on realistic preparation procedures in optical systems, being thus a feasible option to generate and observe genuinely bipartite bound entanglement in high precision experiments. One

Adam K. Leroy, Cheoljong Lee, Andreas Schruba, Alberto Bolatto

Many recent models consider the structure of individual interstellar medium (ISM) clouds as a way to explain observations of large parts of galaxies. To compare such models to observations, one must understand how to translate between surface densities observed averaging over large (~kpc) scales and surface densities on the scale of individual clouds (~pc sc

Changna Lu, Weizhang Huang, Erik S. Van Vleck

The cutoff method, which cuts off the values of a function less than a given number, is studied for the numerical computation of nonnegative solutions of parabolic partial differential equations. A convergence analysis is given for a broad class of finite difference methods combined with cutoff for linear parabolic equations. Two applications are investigate

Jose Reslen

A protocol to obtain the matrix product state representation of a class of boson states is introduced. The proposal is presented in the context of linear systems and is tested by performing simulations of a reference model. The method can be applied regardless of the details of the coupling among modes and can be used to extract the most significant contribu

Piotr J. Flatau

On March 11, 2013 I talked with Warren Wiscombe about his contributions to scientific computer programming, atmospheric science and radiative transfer. Our conversation is divided into three parts related to light scattering, radiative transfer and his general thoughts about scientific programming. There are some reflections on how radiative transfer paramet

Makoto Maejima, Jan Rosinski, Yohei Ueda

In this paper we find and develop a stochastic integral representation for the class of strictly stable distributions. We establish an explicit relationship between stochastic integral and shot-noise series representations of strictly stable distributions, which shows that the class of distributions representable by stochastic integral is larger than the cla

Nan Hu, Raif M. Rustamov, Leonidas Guibas

In this paper, we consider the approximate weighted graph matching problem and introduce stable and informative first and second order compatibility terms suitable for inclusion into the popular integer quadratic program formulation. Our approach relies on a rigorous analysis of stability of spectral signatures based on the graph Laplacian. In the case of th

Pedro Colin, Enrique Vazquez-Semadeni, Gilberto C. Gomez

We present a numerical study of the evolution of molecular clouds, from their formation by converging flows in the warm ISM, to their destruction by the ionizing feedback of the massive stars they form. We improve with respect to our previous simulations by including a different stellar-particle formation algorithm, which allows them to have masses correspon

Roja Bandari, Hazhir Rahmandad, Vwani P. Roychowdhury

We propose an automated and unsupervised methodology for a novel summarization of group behavior based on content preference. We show that graph theoretical community evolution (based on similarity of user preference for content) is effective in indexing these dynamics. Combined with text analysis that targets automatically-identified representative content

Jaydeb Sarkar

We say that a submodule $\cls$ of $H^2(\mathbb{D}^n)$ ($n >1$) is co-doubly commuting if the quotient module $H^2(\mathbb{D}^n)/\cls$ is doubly commuting. We show that a co-doubly commuting submodule of $H^2(\mathbb{D}^n)$ is essentially doubly commuting if and only if the corresponding one variable inner functions are finite Blaschke products or that $n = 2

Michael Aumer, Simon White, Thorsten Naab, Cecilia Scannapieco

We present an update to the multiphase SPH galaxy formation code by Scannapieco et al. We include a more elaborate treatment of the production of metals, cooling rates based on individual element abundances, and a scheme for the turbulent diffusion of metals. Our SN feedback model now transfers energy to the ISM in kinetic and thermal form, and we include a

Yongqing Huang, Anzhong Wang, Razieh Yousefi, Tao Zhu

In this paper, we study 3-point correlation function of primordial gravitational waves generated in the de Sitter background in the framework of the general covariant Hořava-Lifshitz gravity with an arbitrary coupling constant $λ$. We find that, at cubic order, the interaction Hamiltonian receives contributions from four terms built of the 3-dimensional Ricc

K. Indulekha

Two puzzles associated with open clusters have attracted a lot of attention -- their formation, with densities and velocity dispersions that are not too different from those of the star forming regions in the Galaxy, given that the observed Star Formation Efficiencies (SFE) are low and, the mass segregation observed / inferred in some of them, at ages signif

David Liu, Lucas H. Gabrielli, Michal Lipson, Steven G. Johnson

We present a new technique for the design of transformation-optics devices based on large-scale optimization to achieve the optimal effective isotropic dielectric materials within prescribed index bounds, which is computationally cheap because transformation optics circumvents the need to solve Maxwell&#39;s equations at each step. We apply this technique to

Hongtao Lin, Okechukwu Ogbuu, Jifeng Liu, Lin Zhang

In this paper, we quantitatively analyzed the trade-off between energy per bit for switching and modulation bandwidth of classical electro-optic modulators. A formally simple energy-bandwidth limit (Eq. 10) is derived for electro-optic modulators based on intra-cavity index modulation. To overcome this limit, we propose a dual cavity modulator device which u

Savdeep Sethi

I suggest the possibility of a new string in ten dimensions. Evidence for this string is presented both from orientifold physics and from K-theory, along with a mystery concerning the M-theory description. Motivated by this possibility, some novel aspects of decoupling limits in heterotic/type I theories are described; specifically, the decoupled theory on t

M. S. Fujii, S. Portegies Zwart

Star clusters with multi-mass components dynamically evolve faster than those modeled with equal-mass components. Using a series of direct $N$-body simulations, we investigate the dynamical evolution of star clusters with mass functions, especially their core collapse time. Multi-mass clusters tend to behave like systems with a smaller number of particles, w

Alessandro Roggero, Abhishek Mukherjee, Francesco Pederiva

We introduce a novel many body method which combines two powerful many body techniques, viz., quantum Monte Carlo and coupled cluster theory. Coupled cluster wave functions are introduced as importance functions in a Monte Carlo method designed for the configuration interaction framework to provide rigorous upper bounds to the ground state energy. We benchma

Johan Ugander, Lars Backstrom, Jon Kleinberg

A growing set of on-line applications are generating data that can be viewed as very large collections of small, dense social graphs -- these range from sets of social groups, events, or collaboration projects to the vast collection of graph neighborhoods in large social networks. A natural question is how to usefully define a domain-independent coordinate s

Rudro R. Biswas

We consider Majorana fermions tunneling among an array of vortices in a 2D chiral p-wave superconductor or equivalent material. The amplitude for Majorana fermions to tunnel between a pair of vortices is found to necessarily depend on the background superconducting phase profile; it is found to be proportional to the sine of half the difference between the p

Diego Blas, Mathias Garny, Thomas Konstandin

We discuss the convergence of cosmological perturbation theory. We prove that the polynomial enhancement of the non-linear corrections expected from the effects of soft modes is absent in equal-time correlators like the power or bispectrum. We first show this at leading order by resumming the most important corrections of soft modes to an arbitrary skeleton

P. Kumar, R. Barniol Duran, Z. Bosnjak, T. Piran

Gamma-ray observations of a stellar tidal disruption event (TDE) detected by the Swift satellite and follow up observations in radio, mm, infrared and x-ray bands have provided a rich data set to study accretion onto massive blackholes, production of relativistic jets and their interaction with the surrounding medium. The radio and x-ray data for TDE Swift J

S. J. Murphy, A. Pigulski, D. W. Kurtz, J. C. Suarez

The candidate SX Phe star KIC 11754974 shows a remarkably high number of combination frequencies in the Fourier amplitude spectrum: 123 of the 166 frequencies in our multi-frequency fit are linear combinations of independent modes. Predictable patterns in frequency spacings are seen in the Fourier transform of the light curve. We present an analysis of 180 d

Rodolfo Barniol Duran, Tsvi Piran

We apply relativistic equipartition synchrotron arguments to the radio data of the tidal disruption event candidate Sw 1644+57. We find that, regardless of the details of the equipartition scenario considered, the energy required to produce the observed radio (i.e., energy in magnetic field and radio emitting electrons) must increase by a factor of ~20 durin

Arash Arabi Ardehali, James T. Liu, Phillip Szepietowski

We present the complete Kaluza-Klein spectrum resulting from the compactification of IIB supergravity on S^5/Z_3. Knowledge of this spectrum allows us to perform a holographic computation of the difference of central charges c-a of the dual SU(N)^3 quiver gauge theory. We find the numerical value c-a=3/16, in exact agreement with the field theory result.

Joshua W. Silverstone, Damien Bonneau, Kazuya Ohira, Nob Suzuki

Large-scale integrated quantum photonic technologies will require the on-chip integration of identical photon sources with reconfigurable waveguide circuits. Relatively complex quantum circuits have already been demonstrated, but few studies acknowledge the pressing need to integrate photon sources and waveguide circuits together on-chip. A key step towards

Jerome Bouvier, Konstantin Grankin, Lucas Ellerbroek, Herve Bouy

AA Tau has been monitored for more than 20 years since 1987, exhibiting a nearly constant brightness level of V=12.5 mag. We report here that in 2011 it suddenly faded away, becoming 2 magnitudes fainter in the V-band, and has remained in this deep state since then. We report new optical and near-IR photometry and spectroscopy obtained during the fading even

Qiang Yuan, Xiao-Jun Bi, Guo-Ming Chen, Yi-Qing Guo

The AMS-02 collaboration has just released its first result of the cosmic positron fraction $e^+/(e^-+e^+)$ with high precision up to $\sim 350$ GeV. The AMS-02 result shows the same trend with the previous PAMELA result, which requires extra electron/positron sources on top of the conventional cosmic ray background, either from astrophysical sources or from

Matteo Bertolini, Lorenzo Di Pietro, Flavio Porri

We discuss the holographic counterpart of a recent conjecture regarding R-symmetric RG-flows in four-dimensional supersymmetric field theories. In such theories, a quantity τ_U can be defined at the fixed points which was conjectured in arXiv:1109.3279 to be larger in the UV than in the IR, τ_U^{UV} > τ_U^{IR}. We analyze this conjecture from a dual supergra

Robert Bennett, Claudia Eberlein

Changes in the magnetic moment of an electron near a dielectric or conducting surface due to boundary-dependent radiative corrections are investigated. The electromagnetic field is quantized by normal mode expansion for a non-dispersive dielectric and an undamped plasma, but the electron is described by the Dirac equation without matter-field quantization. P

J. Rodi, M. L. Cherry, G. L. Case, A. Camero-Arranz

The Earth Occultation Technique (EOT) has been applied to Fermi&#39;s Gamma-ray Burst Monitor (GBM) to perform all-sky monitoring for a predetermined catalog of hard X-ray/soft gamma-ray sources. In order to search for sources not in the catalog, thus completing the catalog and reducing a source of systematic error in EOT, an imaging method has been develope

Matthew Newby, Nathan Cole, Heidi Jo Newberg, Travis Desell

We measure the spatial density of F turnoff stars in the Sagittarius dwarf tidal stream, from Sloan Digital Sky Survey (SDSS) data, using statistical photometric parallax. We find a set of continuous, consistent parameters that describe the leading Sgr stream&#39;s position, direction, and width for 15 stripes in the North Galactic Cap, and 3 stripes in the

Rodolfo Gambini, Javier Olmedo

We provide a detailed comparison of the different approaches available for the quantization of a totally constrained system with a constraint algebra generating the non-compact $SL(2,\mathbb{R})$ group. In particular, we consider three schemes: the Refined Algebraic Quantization, the Master Constraint Programme and the Uniform Discretizations approach. For t

M. Iskin

We study the interplay between the Zeeman field and spin-orbit coupling (SOC) in harmonically trapped Fermi gases loaded into a two-dimensional single-band tight-binding optical lattice. Using the Bogoliubov-de Gennes theory, we find that the Zeeman field combined with a Rashba SOC gives rise to $(i)$ Fulde-Ferrell-like superfluidity and $(ii)$ skyrmion-like

David Geissbuhler, Diego Marques, Carmen Nunez, Victor Penas

We present a flux formulation of Double Field Theory, in which geometric and non-geometric fluxes are dynamical and field-dependent. Gauge consistency imposes a set of quadratic constraints on the dynamical fluxes, which can be solved by truly double configurations. The constraints are related to generalized Bianchi Identities for (non-)geometric fluxes in t

Jiangyong Jia, Soumya Mohapatra

The performance of the Bayesian unfolding method in extracting the event-by-event (EbyE) distributions of harmonic flow coefficients v_n is investigated using a toy model simulation, as well as simulations based on the HIJING and AMPT models. The unfolding method is shown to recover the input v_2-v_4 distributions for multiplicities similar to those observed

Reza Bosagh Zadeh, Gunnar Carlsson

We compute the singular values of an $m \times n$ sparse matrix $A$ in a distributed setting, without communication dependence on $m$, which is useful for very large $m$. In particular, we give a simple nonadaptive sampling scheme where the singular values of $A$ are estimated within relative error with constant probability. Our proven bounds focus on the Ma

Korkut Bardakci

Following earlier work on the same topic, we consider once more scalar field theories on the world sheet parametrized by the light cone coordinates. For most of the way, we use the same approach as in the previous work, but there is an important new development. To avoid the light cone singularity at p^{+}=0, one world sheet coordinate had to be discretized,

Michael Braun, Tuvi Etzion, Patric Ostergard, Alexander Vardy

Let $\F_q^n$ be a vector space of dimension $n$ over the finite field $\F_q$. A $q$-analog of a Steiner system (briefly, a $q$-Steiner system), denoted $S_q[t,k,n]$, is a set $S$ of $k$-dimensional subspaces of $\F_q^n$ such that each $t$-dimensional subspace of $\F_q^n$ is contained in exactly one element of $S$. Presently, $q$-Steiner systems are known onl

Brian J. Parshall, Leonard L. Scott

Let $G$ be a semisimple algebraic group over an algebraically closed field $k$ of positive characteristic $p$. Under some restrictions on the size of $p$, the present paper establishes new results on the $G$-module structure of $\Ext^\bullet_{G_1}(V,W)$ when $V,W$ belong to several important classes of rational $G$-modules, and $G_1$ denotes the first Froben

L. C. Bland, E. J. Brash, H. J. Crawford, A. A. Derevschikov

Measurements of the production of forward jets from transversely polarized proton collisions at $\sqrt{s}=500$ GeV conducted at the Relativistic Heavy Ion Collider (RHIC) are reported. Our measured jet cross section is consistent with hard scattering expectations. Our measured analyzing power for forward jet production is small and positive, and provides con

Lorenzo Calibbi, Paride Paradisi, Robert Ziegler

We study a minimal modification of Gauge Mediation in which the messenger sector couples directly to the MSSM matter fields. These couplings are controlled by the same dynamics that explain the flavor hierarchies, and therefore are parametrically as small as the Yukawas. This setup gives rise to an interesting SUSY spectrum that is calculable in terms of a s

Justin C. W. Song, Dmitry A. Abanin, Leonid S. Levitov

Recent measurements revealed an anomalous Coulomb drag in graphene, hinting at new physics at charge neutrality. The anomalous drag is explained by a new mechanism based on energy transport, which involves interlayer energy transfer, coupled to charge flow via lateral heat currents and thermopower. The old and new drag mechanisms are governed by distinct phy

Lior Kamma, Robert Krauthgamer, Huy L. Nguyen

Our main result is that the Steiner Point Removal (SPR) problem can always be solved with polylogarithmic distortion, which answers in the affirmative a question posed by Chan, Xia, Konjevod, and Richa (2006). Specifically, we prove that for every edge-weighted graph $G = (V,E,w)$ and a subset of terminals $T \subseteq V$, there is a graph $G&#39;=(T,E&#39;,

Nicolas Libedinsky

We introduce the Double leaves basis, a combinatorial basis for the Hom spaces between two Bott-Samelson-Soergel bimodules. As an application we give a combinatorial algorithm to find, for any given Weyl or affine Weyl group, the set of primes for which Soergel's conjecture hold. This conjecture for Weyl groups is equivalent to a part of Lusztig's conjecture

Thomas Bloom

For Y a subset of the complex plane,a beta ensemble is a sequence of probability measures on Y^n for n=1,2,3...depending on a real-valued continuous function Q and a real positive parameter beta.We consider the associated sequence of probability measures on Y where the probability of a subset W is given by the probability that at least one coordinate of Y^n

Pablo G. Barrientos, Abbas Fakhari, Ali Sarizadeh

We study the minimality of almost every orbital branch of minimal iterated function systems (IFSs). We prove that this kind of minimality holds for forward and backward minimal IFSs generated by orientation-preserving homeomorphisms of the circle. We provide new examples of iterated functions systems where this behavior persists under perturbation of the gen

Christopher T. Haynes, David Burgess, Enrico Camporeale

Turbulent behavior at sub-proton scales in magnetized plasmas is important for a full understanding of the energetics of astrophysical flows such as the solar wind. We study the formation of electron temperature anisotropy due to reconnection in the turbulent decay of sub-proton scale fluctuations using two dimensional, particle-in-cell (PIC) plasma simulati

A. G. Magner, A. A. Vlasenko, K. Arita

The trace formula for the density of single-particle levels in the two-dimensional radial power-law potentials, which nicely approximate the radial dependence of the Woods-Saxon potential and quantum spectra in a bound region, was derived by the improved stationary phase method. The specific analytical results are obtained for the powers 4 and 6. The enhance

Antonio Cañete, César Rosales

We consider a smooth Euclidean solid cone endowed with a smooth homogeneous density function used to weight Euclidean volume and hypersurface area. By assuming convexity of the cone and a curvature-dimension condition we prove that the unique compact, orientable, second order minima of the weighted area under variations preserving the weighted volume and wit

Wojciech Ganczarek

Most of the common used models of epidemic spreading allow contaminating many neighbors of a particular node in the network. They are usually analyzed by differential equations on probability vectors. We propose a model of epidemic spreading, which restricts to at most one contamination per time step and analyze it by discrete approach, working on vectors of

Dmitry K. Efimkin, Yurii E. Lozovik

Tunneling between opposite surfaces of topological insulator thin film populated by electrons and holes is considered. We predict considerable enhancement of tunneling conductivity by Cooper electron-hole pair fluctuations that are precursor of their Cooper pairing. Cooper pair fluctuations lead to the critical behavior of tunneling conductivity in vicinity

J. C. C. de Souza, M. O. C. Pires

We assume that the galactical dark matter halo, considered composed of an axionlike particles Bose-Einstein condensate \cite{pir12}, can present topological defects, namely domain walls, arising as the dark soliton solution for the Gross-Pitaevskii equation in a self-graviting potential. We investigate the influence that such substructures would have in the

Giorgio Volpe, Giovanni Volpe, Sylvain Gigan

The motion of particles in random potentials occurs in several natural phenomena ranging from the mobility of organelles within a biological cell to the diffusion of stars within a galaxy. A Brownian particle moving in the random optical potential associated to a speckle, i.e., a complex interference pattern generated by the scattering of coherent light by a

Carlos Gershenson

In this chapter, concepts related to information and computation are reviewed in the context of human computation. A brief introduction to information theory and different types of computation is given. Two examples of human computation systems, online social networks and Wikipedia, are used to illustrate how these can be described and compared in terms of i

The XENON100 Collaboration, E. Aprile, M. Alfonsi, K. Arisaka

Results from the nuclear recoil calibration of the XENON100 dark matter detector installed underground at the Laboratori Nazionali del Gran Sasso (LNGS), Italy are presented. Data from measurements with an external 241AmBe neutron source are compared with a detailed Monte Carlo simulation which is used to extract the energy dependent charge-yield Qy and rela

Marek Cygan

One of the most natural optimization problems is the k-Set Packing problem, where given a family of sets of size at most k one should select a maximum size subfamily of pairwise disjoint sets. A special case of 3-Set Packing is the well known 3-Dimensional Matching problem. Both problems belong to the Karp`s list of 21 NP-complete problems. The best known po

Felipe F. B. Araújo, Alysson M. Costa, Cristóbal Miralles

We study an assembly line balancing problem that occurs in sheltered worker centers for the disabled, where workers with very different characteristics are present. We are interested in the situation in which parallel assembly lines are allowed and name the resulting problem as parallel assembly line worker assignment and balancing problem. We present a line

Ivan P. Christov

In this paper we use sets of de Broglie-Bohm trajectories to describe the quantum correlation effects which take place between the electrons in helium atom due to exchange and Coulomb interactions. A short-range screening of the Coulomb potential is used to modify the repulsion between the same spin electrons in physical space in order to comply with the Pau

Konstantinos Spiliopoulos, Justin A. Sirignano, Kay Giesecke

We analyze the fluctuation of the loss from default around its large portfolio limit in a class of reduced-form models of correlated firm-by-firm default timing. We prove a weak convergence result for the fluctuation process and use it for developing a conditionally Gaussian approximation to the loss distribution. Numerical results illustrate the accuracy an

Viktor Eisler

We study the distribution of particle number in extended subsystems of a one-dimensional non-interacting Fermi gas confined in a potential well at zero temperature. Universal features are identified in the scaled bulk and edge regions of the trapped gas where the full counting statistics are given by the corresponding limits of the eigenvalue statistics in G

Quoc Trung Tran, Ivo Jimenez, Rui Wang, Neoklis Polyzotis

Given a replicated database, a divergent design tunes the indexes in each replica differently in order to specialize it for a specific subset of the workload. This specialization brings significant performance gains compared to the common practice of having the same indexes in all replicas, but requires the development of new tuning tools for database admini

M. V. Koroteev, J. Miller

Motivated by empirical observations of algebraic duplicated sequence length distributions in a broad range of natural genomes, we analytically formulate and solve a class of simple discrete duplication/substitution models that generate steady-states sharing this property. Continuum equations are derived for arbitrary time-independent duplication length sourc

Marie Dostálová, Petr Somberg

The aim of our article is the study of solution space of the symplectic twistor operator $T_s$ in symplectic spin geometry on standard symplectic space $({\mathbb R}^{2n},ω)$, which is the symplectic analogue of the twistor operator in (pseudo)Riemannian spin geometry. In particular, we observe a substantial difference between the case $n=1$ of real dimensio

Yanqi Qiu

We give a new proof to show that the complex interpolation for families of Banach spaces is not stable under rearrangement of the given family on the boundary, although, by a result due to Coifman, Cwikel, Rochberg, Sagher and Weiss, it is stable when the latter family takes only 2 values. The non-stability for families taking 3 values was first obtained by

Bernardo Cuenca Grau, Boris Motik, Giorgos Stoilos, Ian Horrocks

Rewriting-based approaches for answering queries over an OWL 2 DL ontology have so far been developed mainly for Horn fragments of OWL 2 DL. In this paper, we study the possibilities of answering queries over non-Horn ontologies using datalog rewritings. We prove that this is impossible in general even for very simple ontology languages, and even if PTIME =

Satyendra Thoudam, Jörg R. Hörandel

Measurements of cosmic rays by experiments such as ATIC, CREAM, and PAMELA indicate a hardening of the cosmic-ray energy spectrum at TeV energies. In our recent work (Thoudam & Hörandel 2012a), we showed that the hardening can be due to the effect of nearby supernova remnants. We showed it for the case of proton and helium. In this paper, we present an impro

Marc Hallin, Thomas Verdebout, Yvik Swan

While the asymptotic relative efficiency (ARE) of Wilcoxon rank-based tests for location and regression with respect to their parametric Student competitors can be arbitrarily large, Hodges and Lehmann (1961) have shown that the ARE of the same Wilcoxon tests with respect to their van der Waerden or normal-score counterparts is bounded from above by $6/π\app

Johan Segers, Nathan Uyttendaele

One of the features inherent in nested Archimedean copulas, also called hierarchical Archimedean copulas, is their rooted tree structure. A nonparametric, rank-based method to estimate this structure is presented. The idea is to represent the target structure as a set of trivariate structures, each of which can be estimated individually with ease. Indeed, fo

David Preinerstorfer, Benedikt M. Pötscher

Testing restrictions on regression coefficients in linear models often requires correcting the conventional F-test for potential heteroskedasticity or autocorrelation amongst the disturbances, leading to so-called heteroskedasticity and autocorrelation robust test procedures. These procedures have been developed with the purpose of attenuating size distortio

Aleksandar Mijatović, Mikhail Urusov

This paper studies the loss of the semimartingale property of the process $g(Y)$ at the time a one-dimensional diffusion $Y$ hits a level, where $g$ is a difference of two convex functions. We show that the process $g(Y)$ can fail to be a semimartingale in two ways only, which leads to a natural definition of non-semimartingales of the \textit{first} and \te

Amaury Mouchet

According to Wigner theorem, transformations of quantum states which preserve the probabilities are either unitary or antiunitary. This short communication presents an elementary proof of this theorem that significantly departs from the numerous ones already existing in the literature. The main line of the argument remains valid even in quantum field theory

Thierry Bouche, Jiri Rákosnik

One of the main tasks of the European Digital Mathematics Library project was to define a cooperation model with a variety of stakeholders that would allow building a reliable and durable global reference library, aiming to be eventually exhaustive. In this paper we present the EuDML external cooperation model and the business plan as the basis for its susta

Jun-Hwan Choi, Isaac Shlosman, Mitchell C. Begelman

We use numerical simulations to explore whether direct collapse can lead to the formation of SMBH seeds at high-z. We follow the evolution of gas within DM halos of 2 x 10^8 Mo and 1 kpc. We adopt cosmological density profiles and j-distributions. Our goal is to understand how the collapsing flow overcomes the centrifugal barrier and whether it is subject to

Jonathan Carroll-Nellenback, Adam Frank, Fabian Heitsch

Observational evidence from local star-forming regions mandates that star formation occurs shortly after, or even during, molecular cloud formation. Models of the formation of molecular clouds in large-scale converging flows have identified the physical mechanisms driving the necessary rapid fragmentation. They also point to global gravitational collapse dri

E. A. Ivanov, B. M. Zupnik

We update and detail the formulation of the duality-invariant systems of N interacting abelian gauge fields with N auxiliary bispinor fields added. In this setting, the self-duality amounts to U(N) invariance of the nonlinear interaction of the auxiliary fields. The U(N) self-dual Lagrangians arise after solving the nonlinear equations of motion for the auxi

Robert J. Rutten, Gregal J. M. Vissers, Luc H. M. Rouppe van der Voort, Peter Sütterlin

Ellerman bombs are short-lived brightenings of the outer wings of Halpha that occur in active regions with much flux emergence. We point out fads and fallacies in the extensive Ellerman bomb literature, discuss their appearance in various spectral diagnostics, and advocate their use as indicators of field reconfiguration in active-region topography using AIA

Zeyu Guo, He Sun

We study the classical rumor spreading problem, which is used to spread information in an unknown network with $n$ nodes. We present the first protocol for any expander graph $G$ with $n$ nodes and minimum degree $Θ(n)$ such that, the protocol informs every node in $O(\log n)$ rounds with high probability, and uses $O(\log n\log\log n)$ random bits in total.

Tinne De Laet, Wouter Schaekers, Jonas de Greef, Herman Bruyninckx

This paper presents a DSL for geometric relations between rigid bodies such as relative position, orientation, pose, linear velocity, angular velocity, and twist. The DSL is the formal model of the recently proposed semantics for the standardization of geometric relations between rigid bodies, referred to as `geometric semantics&#39;. This semantics explicit

Wen-ling Huang, Hans Havlicek

We consider a class of graphs subject to certain restrictions, including the finiteness of diameters. Any surjective mapping $\phi:\Gamma\to\Gamma'$ between graphs from this class is shown to be an isomorphism provided that the following holds: Any two points of $\Gamma$ are at a distance equal to the diameter of $\Gamma$ if, and only if, their images are at

Hans Havlicek, Corrado Zanella

In this paper a generalisation of the notion of polarity is exhibited which allows to completely describe, in an incidence-geometric way, the linear complexes of $h$-subspaces. A generalised polarity is defined to be a partial map which maps $(h-1)$-subspaces to hyperplanes, satisfying suitable linearity and reciprocity properties. Generalised polarities wit

Roman Orus, Tzu-Chieh Wei, Oliver Buerschaper, Maarten Van den Nest

Here we investigate the connection between topological order and the geometric entanglement, as measured by the logarithm of the overlap between a given state and its closest product state of blocks. We do this for a variety of topologically-ordered systems such as the toric code, double semion, color code, and quantum double models. As happens for the entan