August 2010 arXiv papers — page 18

Ishanu Chattopadhyay, Anthony Cascone, Asok Ray

We report a globally-optimal approach to robotic path planning under uncertainty, based on the theory of quantitative measures of formal languages. A significant generalization to the language-measure-theoretic path planning algorithm $\nustar$ is presented that explicitly accounts for average dynamic uncertainties and estimation errors in plan execution. Th

Akram Hakiri, Pascal Berthou, Thierry Gayraud

Real-Time availability of information is of most importance in large scale distributed interactive simulation in network-centric communication. Information generated from multiple federates must be distributed and made available to interested parties and providing the required QoS for consistent communication. The remainder of this paper discuss design alter

Akram Hakiri, Pascal Berthou, Thierry Gayraud

Dead Reckoning mechanism allows reducing the network utilization considerably when used in Distributed Interactive Simulation Applications. However, this technique often ignores available contextual information that may be influential to the state of an entity, sacrificing remote predictive accuracy in favor of low computational complexity. The remainder of

Chung-Hou Chung

We calculate the dynamical decoherence rate and susceptibility of a nonequilibrium quantum dot close to the delocalized-to-localized quantum phase transitions. The setup concerns a resonance-level coupled to two spinless fermionic baths with a finite bias voltage and an Ohmic bosonic bath representing the dissipative environment. The system is equivalent to

Mark J. Ablowitz, Sean D. Nixon, Theodoros P. Horikis, Dimitri J. Frantzeskakis

A method for approximating dark soliton solutions of the nonlinear Schrodinger equation under the influence of perturbations is presented. The problem is broken into an inner region, where core of the soliton resides, and an outer region, which evolves independently of the soliton. It is shown that a shelf develops around the soliton which propagates with sp

Toshitaka Tatsumi

Some magnetic aspects of QCD are discussed at finite density and temperature. Possibility of spontaneous magnetization is studied within Landau Fermi-liquid theory, and the important roles of the screening effects for gluon propagation are elucidated. Static screening for the longitudinal gluons improves the infrared singularities, while the transverse gluon

Sudipto Das, Divyakant Agrawal, Amr El Abbadi

Over the last couple of years, "Cloud Computing" or "Elastic Computing" has emerged as a compelling and successful paradigm for internet scale computing. One of the major contributing factors to this success is the elasticity of resources. In spite of the elasticity provided by the infrastructure and the scalable design of the applications, t

Alexander I. Milstein, Ivan S. Terekhov

The induced current density, corresponding to the massless Dirac equation in (2+1) dimensions in a magnetic flux tube of small radius is considered. This problem is important for graphene. In the case, when an electron can not penetrate the region of nonzero magnetic field, this current is the odd periodical function of the magnetic flux. If the region insid

Kusuda, M

Let $A$ be a $C^*$-algebra. It is shown that the following conditions are equinvalent: (1) $A$ is scattered, (2) every $C^*$-subalgebra of $A$ is AF, (3) every $C^*$-subalgebra of $A$ has real rank zero.

B. Bergk, A. Demuer, I. Sheikin, Y. Wang

We present magnetic-torque measurements of the organic superconductor k-(BEDT-TTF)2Cu(NCS)2 for in-plane magnetic fields up to 32 T. In this layered two-dimensional compound the superconductivity can persist even in fields above the Pauli limit of about 21 T. There, a pronounced upturn of the upper-critical-field line occurs and the superconducting phase-tra

M. Tiwari, D. V. Seletskiy, V. M. Kenkre

The quantum nonlinear dimer consisting of an electron shuttling between the two sites and in weak interaction with vibrations, is studied numerically under the application of a DC electric field. A field-induced resonance phenomenon between the vibrations and the electronic oscillations is found to influence the electronic transport greatly. For initially de

Leopoldo Bertossi, Solmaz Kolahi, Laks V. S. Lakshmanan

Matching dependencies were recently introduced as declarative rules for data cleaning and entity resolution. Enforcing a matching dependency on a database instance identifies the values of some attributes for two tuples, provided that the values of some other attributes are sufficiently similar. Assuming the existence of matching functions for making two att

Chunhua Shen, Peng Wang, Anton van den Hengel

Cascade classifiers are widely used in real-time object detection. Different from conventional classifiers that are designed for a low overall classification error rate, a classifier in each node of the cascade is required to achieve an extremely high detection rate and moderate false positive rate. Although there are a few reported methods addressing this r

C. Y. Ryu, K. S. Kim, Myung-Ki Cheoun

We investigate medium effects due to density-dependent magnetic moments of baryons on neutron stars under strong magnetic fields. If we allow the variation of anomalous magnetic moments (AMMs) of baryons in dense matter under strong magnetic fields, AMMs of nucleons are enhanced to be larger than those of hyperons. The enhancement naturally affects the chemi

Angelos Vourlidas, Russ A. Howard, Ed Esfandiari, Spiros Patsourakos

The LASCO coronagraphs, in continuous operation since 1995, have observed the evolution of the solar corona and coronal mass ejections (CMEs) over a full solar cycle with high quality images and regular cadence. This is the first time that such a dataset becomes available and constitutes a unique resource for the study of CMEs. In this paper, we present a co

Issei Yamamura, Takashi Tsuji, Toshihiko Tanabe

Near-infrared medium-resolution spectra of seven bright brown dwarfs are presented. The spectra were obtained with the Infrared Camera (IRC) on board the infrared astronomical satellite AKARI, covering 2.5--5.0 um with a spectral resolution of approximately 120. The spectral types of the objects range from L5 to T8, and enable us to study the spectral evolut

Amitav Mukherjee, A. Lee Swindlehurst

Accurate channel state information (CSI) at the transmitter is critical for maximizing spectral efficiency on the downlink of multi-antenna networks. In this work we analyze a novel form of physical layer attacks on such closed-loop wireless networks. Specifically, this paper considers the impact of deliberately inaccurate feedback by malicious users in a mu

Stefano Chesi, Gabriele F. Giuliani

We discuss by analytic means the theory of the high-density limit of the unpolarized two-dimensional electron liquid in the presence of Rashba or Dresselhaus spin-orbit coupling. A generalization of the ring-diagram expansion is performed. We find that in this regime the spin-orbit coupling leads to small changes of the exchange and correlation energy contri

F. Hamann, N. Kanekar, J. X. Prochaska, M. T. Murphy

We report on a variable high-velocity narrow absorption line outflow in the redshift 2.3 quasar J2123-0050. Five distinct outflow systems are detected with velocity shifts from -9710 to -14,050 km/s and CIV 1548,1551 line widths of FWHM = 62-164 km/s. These data require five distinct outflow structures with similar kinematics, physical conditions and charact

Łukasz Delong

In this paper we consider backward stochastic differential equations with time-delayed generators of a moving average type. The classical framework with linear generators depending on $(Y(t),Z(t))$ is extended and we investigate linear generators depending on $(\frac{1}{t}\int_0^tY(s)ds, \frac{1}{t}\int_0^tZ(s)ds)$. We derive explicit solutions to the corres

M. Tafelmeyer, P. Jablonka, V. Hill, M. Shetrone

We present the results of a dedicated search for extremely metal-poor stars in the Fornax, Sculptor and Sextans dSphs. Five stars were selected from two earlier VLT/Giraffe and HET/HRS surveys and subsequently followed up at high spectroscopic resolution with VLT/UVES. All of them turned out to have [Fe/H] <= -3 and three stars are below [Fe/H] -3.5. This co

A. H. Raduta

A Path Integral Monte Carlo method is used to investigate the thermodynamics of nuclear like systems. Systems composed of bosons or fermions interracting via a Lennard-Jones potential with periodic boundary conditions were simulated and the corresponding phase diagrams are constructed. The Path Integral Monte Carlo appears to be a powerfull tool for investig

Jeroen Demeyer, Antonella Perucca

Let A be an abelian variety defined over a number field K and let P and Q be points in A(K) satisfying the following condition: for all but finitely many primes p of K, the order of (Q mod p) divides the order of (P mod p). Larsen proved that there exists a positive integer c such that cQ is in the End_K(A)-module generated by P. We study the minimal value o

Kung-Yi Su, Pisin Chen

Matos, Guzman and Nunez proposed a model of galactic halo based on an exponential-potential scalar field that could induce a rotation curve that is constant for all radii. We demonstrate that with suitable boundary conditions, such scalar field dark matter (SDM) can not only produce the observed constant rotation curve at large radius but also give rise to t

Roman Pasechnik, Antoni Szczurek, Oleg Teryaev

We consider exclusive double diffractive production of polarised axial-vector $χ_c(1^+)$ and tensor $χ_c(2^+)$ charmonia in proton-(anti)proton collisions at Tevatron energy. The corresponding amplitudes for these processes are derived within the $k_t$-factorisation approach. Contributions from different polarisation states of axial-vector and tensor charmon

Justin Malestein, Igor Rivin, Louis Theran

We give an exponential upper and a quadratic lower bound on the number of pairwise non-isotopic simple closed curves can be placed on a closed surface of genus g such that any two of the curves intersects at most once. Although the gap is large, both bounds are the best known for large genus. In genus one and two, we solve the problem exactly. Our methods ge

Farnood Merrikh-Bayat, Saeed Bagheri-Shouraki, Ali Rohani

Ink Drop Spread (IDS) is the engine of Active Learning Method (ALM), which is the methodology of soft computing. IDS, as a pattern-based processing unit, extracts useful information from a system subjected to modeling. In spite of its excellent potential in solving problems such as classification and modeling compared to other soft computing tools, finding i

J. L. Chkareuli, J. G. Jejelava, G. Tatishvili

Spontaneous Lorentz invariance violation (SLIV) realized through a nonlinear tensor field constraint H_{}^2=\pm M^2 (M is the proposed scale for Lorentz violation) is considered in tensor field gravity theory, which mimics linearized general relativity in Minkowski space-time. We show that such a SLIV pattern, due to which the true vacuum in the theory is ch

Xing Wei

We investigate analytically the magnetic instability in a rotating and electrically conducting fluid induced by an imposed magnetic field with its associated electric current. The short-wavelength approximation is used in the linear stability analysis, i.e. the length scale of the imposed field is much larger than the wavelength of perturbations. The dispers

J. R. Williams, Tony Low, M. S. Lundstrom, C. M. Marcus

Ballistic semiconductor structures have allowed the realization of optics-like phenomena in electronics, including magnetic focusing and lensing. An extension that appears unique to graphene is to use both n and p carrier types to create electronic analogs of optical devices having both positive and negative indices of refraction. Here, we use gate-controlle

The CTA Consortium

Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 i

Camille Duprat, Jeffrey M. Aristoff, Howard A. Stone

We present the results of a combined experimental and theoretical investigation of the surface-tension-driven coalescence of flexible structures. Specifically, we consider the dynamics of the rise of a wetting liquid between flexible sheets that are clamped at their upper ends. As the elasticity of the sheets is progressively increased, we observe a systemat

Dave Benson, Srikanth B. Iyengar, Henning Krause

The Hom closed colocalizing subcategories of the stable module category of a finite group are classified. Along the way, the colocalizing subcategories of the homotopy category of injectives over an exterior algebra, and the derived category of a formal commutative differential graded algebra, are classified. To this end, and with an eye towards future appli

Alice Mikikits-Leitner, Gerald Teschl

We apply the method of nonlinear steepest descent to compute the long-time asymptotics of solutions of the Korteweg--de Vries equation which are decaying perturbations of a quasi-periodic finite-gap background solution. We compute a nonlinear dispersion relation and show that the $x/t$ plane splits into $g+1$ soliton regions which are interlaced by $g+1$ osc

Jose F. Fontanari

We investigate the performance of a variant of Axelrod&#39;s model for dissemination of culture - the Adaptive Culture Heuristic (ACH) - on solving an NP-Complete optimization problem, namely, the classification of binary input patterns of size $F$ by a Boolean Binary Perceptron. In this heuristic, $N$ agents, characterized by binary strings of length $F$ wh

Gang Li, Feng-lan Shao, Wei Wang

Under the assignment of $D_s(3040)$ as a radially excited p-wave $\bar cs$ state with $J^P=1^+$, we compute the $B_s\to D_s (3040)$ form factors within the covariant light-front quark model. Two classification schemes for the p-wave $\bar cs$ meson are adopted. We also use our results to predict the branching ratios (BRs), polarization fractions and angular

Hossein Hajiabolhassan, Farokhlagha Moazami

An $(r,w;d)$ cover-free family $(CFF)$ is a family of subsets of a finite set such that the intersection of any $r$ members of the family contains at least $d$ elements that are not in the union of any other $w$ members. The minimum number of elements for which there exists an $(r,w;d)-CFF$ with $t$ blocks is denoted by $N((r,w;d),t)$. In this paper, we show

David Marín, Jorge Pereira

This paper studies global webs on the projective plane with vanishing curvature. The study is based on an interplay of local and global arguments. The main local ingredient is a criterium for the regularity of the curvature at the neighborhood of a generic point of the discriminant. The main global ingredient, the Legendre transform, is an avatar of classica

Shenghao Sun

We reprove the Lefschetz trace formula for stacks (in the context of derived categories and the six operations for stacks developed by Laszlo and Olsson), and give the meromorphic continuation of L-series (in particular, zeta functions) of Artin stacks over a finite field. We also give an upper bound for the weights of the cohomology groups of stacks, and an

Ziv Rotman, Eli Eisenberg

The super-cooled $N3$ model exhibits an increasingly slow dynamics as density approaches the model&#39;s random closest packing density. Here, we present a direct measurement of the dynamical correlation function $G_4(r,t)$, showing the emergence of a growing length scale $ξ_4$ across which the dynamics is correlated. The correlation length measured, up to 1

Lei Hao, T. K. Lee

We systematically calculate thermopower of biased and unbiased multilayer grphene systems. The effect of screening to a bias field perpendicular to the graphene planes is taken into account self-consistently under the Hartree approximation. The model including nearest neighbor hopping and the more complete Slonczewski-Weiss-McClure (SWMcC) model are both con

Heng Guo, Yu-Xiao Liu, Shao-Wen Wei, Chun-E Fu

In this letter, we first investigate the gravity localization and mass spectrum of gravity KK modes on de Sitter and Anti-de Sitter thick branes. Then, the effective Newtonian gravitational potentials for these bent branes are discussed by the two typical examples. The corrections of the Newtonian potential turns out to be $ΔU(r)\sim 1/r^{2}$ at small $r$ fo

Wei-jie Fu, Yue-liang Wu

We study the fluctuations and correlations of conserved charges, i.e. the baryon number, electric charge and the strangeness at finite temperature and nonzero baryon chemical potential with an effective model. The fluctuations are calculated up to the fourth-order and the correlations to the third-order. We find that the second-order fluctuations and correla

Jianquan Ge, Zizhou Tang

In this note we will review the most important results and questions related to Chern conjecture and isoparametric hypersurfaces, as well as their interactions and applications to various aspects in mathematics.

Xiaofei Qi, Jinchuan Hou

In this paper, a class of indecomposable positive finite rank elementary operators of order $(n,n)$ are constructed. This allows us to give a simple necessary and sufficient criterion for separability of pure states in bipartite systems of any dimension in terms of positive elementary operators of order $(2,2)$ and get some new mixed entangled states that ca

Tokuji Araya, Kei-ichiro Iima, Ryo Takahashi

In this paper, we characterize several properties of commutative notherian local rings in terms of the left perpendicular category of the category of finitely generated modules of finite projective dimension. As an application we prove that a local ring is regular if (and only if) there exists a strong test module for projectivity having finite projective di

Michael Aizenman, Sabine Jansen, Paul Jung

Quasi one-dimensional systems are systems of particles in domains which are of infinite extent in one direction and of uniformly bounded size in all other directions, e.g. on a cylinder of infinite length. The main result proven here is that for such particle systems with Coulomb interactions and neutralizing background, the so-called &#34;jellium&#34;, at a

Rosena R. X. Du, Fu Liu

In this paper, we study factorizations of cycles. The main result is that under certain condition, the number of ways to factor a $d$-cycle into a product of cycles of prescribed lengths is $d^{r-2}.$ To prove our result, we first define a new class of combinatorial objects, multi-noded rooted trees, which generalize rooted trees. We find the cardinality of

Nassim Bozorgnia, Graciela B. Gelmini, Paolo Gondolo

The channeling of the ion recoiling after a collision with a WIMP changes the ionization signal in direct detection experiments, producing a larger signal than otherwise expected. We give estimates of the fraction of channeled recoiling ions in Si and Ge crystals using analytic models produced since the 1960&#39;s and 70&#39;s to describe channeling and bloc

Jordan Ellenberg, Chris Hall, Emmanuel Kowalski

We show that families of coverings of an algebraic curve where the associated Cayley-Schreier graphs form an expander family exhibit strong forms of geometric (genus and gonality) growth. Combining this general result with finiteness statements for rational points under such conditions, we derive results concerning the variation of Galois representations in

Jian Wu, Yuqi Tong, Min Li, Haifeng Pan

We demonstrate that the THz generation in air from a dual-color pulse, composed of the fundamental and second-harmonic waves, can be coherently controlled by field-free molecular alignment. By tuning its time delay to properly match various molecular alignment revivals, the THz generation from the dual-color pulse can be promoted or decreased due to the spat

Michael Kapralov, Rina Panigrahy

Consider a sequence of bits where we are trying to predict the next bit from the previous bits. Assume we are allowed to say &#39;predict 0&#39; or &#39;predict 1&#39;, and our payoff is +1 if the prediction is correct and -1 otherwise. We will say that at each point in time the loss of an algorithm is the number of wrong predictions minus the number of righ

Ryan Schwartz, József Solymosi, Frank de Zeeuw

In 1946 Erd\H os asked for the maximum number of unit distances, $u(n)$, among $n$ points in the plane. He showed that $u(n)> n^{1+c/\log\log n}$ and conjectured that this was the true magnitude. The best known upper bound is $u(n)<cn^{4/3}$, due to Spencer, Szemerédi and Trotter. We show that the upper bound $n^{1+6/\sqrt{\log n}}$ holds if we only consider

Daniel N. Kaslovsky, Francois G. Meyer

Huang&#39;s Empirical Mode Decomposition (EMD) is an algorithm for analyzing nonstationary data that provides a localized time-frequency representation by decomposing the data into adaptively defined modes. EMD can be used to estimate a signal&#39;s instantaneous frequency (IF) but suffers from poor performance in the presence of noise. To produce a meaningf

Abhijit Saha, Edward W. Olszewski, Brian Brondel, Knut Olsen

[abridged] We describe the first results from the NOAO Outer Limits Survey. The survey consists of deep images of 55 0.6x0.6 degree fields at distances up to 20 degrees from the LMC/SMC, and 10 controls. The fields probe the outer structure of the Clouds, the Magellanic Stream, the Leading Arm, and the wake of the new LMC orbit. Images were taken in 5 filter

Douglas R. Anderson

We establish the stability of second-order linear dynamic equations on time scales in the sense of Hyers and Ulam. To wit, if an approximate solution of the second-order linear equation exists, then there exists an exact solution to the dynamic equation that is close to the approximate one.

Grenville J. Croll, David F. Baker, Ola Lawal

Fifty North Sea oil & gas investment transactions were analysed using traditional spreadsheet based financial modelling methods. The purpose of the analysis was to determine if there was a statistically significant relationship between the price paid for an oil & gas asset and the actual or expected financial return over the asset&#39;s economically useful l

Ethan D. Bloch

It is proved that every discrete Morse function in the sense of Forman on a finite regular CW complex can be represented by a polyhedral Morse function in the sense of Banchoff on an appropriate embedding in Euclidean space of the barycentric subdivision of the CW complex; such a representation preserves critical points. The proof is stated in terms of discr

V. V. Mkhitaryan, M. E. Raikh

Localization properties of random-mass Dirac fermions for a realization of mass disorder, commonly referred to as Cho-Fisher model, is studied on the D-class chiral network. We show that a simple RG description captures accurately three phases: thermal metal and two insulators with quantized Hall conductances, as well as transitions between them (including c

William T. Shaw

We develop the idea of using Monte Carlo sampling of random portfolios to solve portfolio investment problems. In this first paper we explore the need for more general optimization tools, and consider the means by which constrained random portfolios may be generated. A practical scheme for the long-only fully-invested problem is developed and tested for the

S. Schadmand

Data on the photoproduction of omega mesons on nuclei have been re-analyzed in search for in-medium modifications. The data were taken with the Crystal Barrel(CB)/TAPS detector system at the ELSA accelerator facility in Bonn. The extracted omega line shape was found to be sensitive to the background subtraction. In experiments at the tagged photon facility o

Carl H. Gibson, N. Chandra Wickramasinghe, Rudolph E. Schild

A key result of hydrogravitational dynamics cosmology relevant to astrobiology is the early formation of vast numbers of hot primordial-gas planets in million-solar-mass clumps as the dark matter of galaxies and the hosts of first life. Photon viscous forces in the expanding universe of the turbulent big bang prevent fragmentations of the plasma for mass sca

D. Cordier, O. Mousis, J. I. Lunine, S. Lebonnois

An unexpected feature of Titan&#39;s atmosphere is the strong depletion in primordial noble gases revealed by the Gas Chromatograph Mass Spectrometer aboard the Huygens probe during its descent on 2005 January 14. Although several plausible explanations have already been formulated, no definitive response to this issue has been yet found. Here, we investigat

Tor Gunston

This thesis is a study of various ways of measuring the size and complexity of finitely generated modules over a Noetherian local ring. The classical example is the multiplicity or degree. Here we investigate several variants of the degree function: the homological Dilworth number, hdil, and the family of cohomological degrees, such as the homological degree

Albert Bae, Eberhard Bodenschatz

Traditionally, the primary mode for locomotion of amoeboid cells was thought to be crawling on a substrate. Recently, it has been experimentally shown that \textit{Dictostelium} amoeba and neutrophils can also swim in a directed fashion. The mechanisms for amoeboid crawling and swimming were hypothesized to be similar. In this letter, we show that the shape

Bruno Galvan

The preferred basis problem is mentioned in the literature in connection with the measurement problem and with the Many World Interpretation. It is argued that this problem actually corresponds to two inequivalent problems: (i) the preferred-decomposition problem, i.e., what singles out a preferred decomposition of a suitable state vector of a system as the

Pedro C. Pinto, Joao Barros, Moe Z. Win

Information-theoretic security--widely accepted as the strictest notion of security--relies on channel coding techniques that exploit the inherent randomness of propagation channels to strengthen the security of communications systems. Within this paradigm, we explore strategies to improve secure connectivity in a wireless network. We first consider the intr

Shun Maeta

J.Eells and L. Lemaire introduced $k$-harmonic maps, and Wang Shaobo showed the first variation formula. In this paper, we give the second variation formula of $k$-energy, and give a notion of index, nullity and weakly stable. We also study $k$-harmonic maps into the product Riemannian manifold, and $k$-harmonic curves into a Riemannian manifold with constan

Ruhollah Tavakoli

There are variety of computational algorithms need sequential sweeping; sweeping based on specific order; on a structured grid, e.g., preconditioning (smoothing) by SOR or ILU methods and solution of eikonal equation by fast sweeping algorithm. Due to sequential nature, parallel implementation of these algorithms usually leads to miss of efficiency; e.g. a s

Lucas R. Peres, Jose F. Fontanari

The existence of juxtaposed regions of distinct cultures in spite of the fact that people&#39;s beliefs have a tendency to become more similar to each other&#39;s as the individuals interact repeatedly is a puzzling phenomenon in the social sciences. Here we study an extreme version of the frequency-dependent bias model of social influence in which an indivi

Clive Neal-Sturgess

In this paper it is shown that statistical mechanics in the form of thermodynamic entropy can be used as a measure of the severity of individual injuries (AIS), and that the correct way to account for multiple injuries is to sum the entropies. It is further shown that summing entropies according to the Planck-Boltzmann (P-B) definition of entropy is formally

Md. Saiful Islam, Md. Rafiqul Islam, Abdullah Al Mahmud, Muhammad Rezaul karim

In this paper, we have introduced an algorithm to implement a sorting network for reversible logic synthesis based on swapping bit strings. The algorithm first constructs a network in terms of n*n Toffoli gates read from left to right. The number of gates in the circuit produced by our algorithm is then reduced by template matching and removing useless gates

E. F. Keane

Here I will review the high time resolution radio sky, focusing on millisecond scales. This is primarily occupied by neutron stars, the well-known radio pulsars and the recently identified group of transient sources known as Rotating RAdio Transients (RRATs). The RRATs appear to be abundant in the Galaxy, which at first glance may be difficult to reconcile w

Elahe Zohoorian Azad

In this article, we study a type of a one dimensional percolation model whose basic features include a sequential dropping of particles on a substrate followed by their transport via a pushing mechanism (see [S. N. Majumdar and D. S. Dean, Phys. Rev. Ltt. A 11, 89 (2002)]). Consider an empty one dimensional lattice with n empty sites and periodic boundary co

Jeremiah Heller, Mircea Voineagu

We establish an Atiyah-Hirzebruch type spectral sequence relating real morphic cohomology and real semi-topological K-theory and prove it to be compatible with the Atiyah-Hirzebruch spectral sequence relating Bredon cohomology and Atiyah&#39;s KR-theory constructed by Dugger. An equivariant and a real version of Suslin&#39;s conjecture on morphic cohomology

Rajender Kumar, Brahmjit Singh

Fourth Generation (4G) Wireless System will integrate heterogeneous wireless overlay systems i.e. interworking of WLAN/ GSM/ CDMA/ WiMAX/ LTE/ etc with guaranteed Quality of Service (QoS) and Experience (QoE).QoS(E) vary from network to network and is application sensitive. User needs an optimal mobility solution while roaming in Overlaid wireless environmen

Anna Felikson, Sergey Natanzon

A double pants decomposition of a 2-dimensional surface is a collection of two pants decomposition of this surface introduced in arXiv:1005.0073v2. There are two natural operations acting on double pants decompositions: flips and handle twists. It is shown in arXiv:1005.0073v2 that the groupoid generated by flips and handle twists acts transitively on admiss

Lhoussain El Fadil

For every prime integer $p$, an explicit factorization of the principal ideal $p\z_K$ into prime ideals of $\z_K$ is given, where $K$ is a quartic number field defined by an irreducible polynomial $X^4+aX+b\in\z[X]$.

D. Bennett, V. Skavysh, J. Long

An experimental test of the Newtonian inverse square law at short range has been used to set limits on Lorentz violation in the pure gravity sector of the Standard-Model Extension. On account of the planar test mass geometry, nominally null with respect to inverse square forces, the limits derived for the SME coefficients of Lorentz violation are on the orde

Puxun Wu, Hongwei Yu

In this paper, we propose two new models in $f(T)$ gravity to realize the crossing of the phantom divide line for the effective equation of state, and we then study the observational constraints on the model parameters. The best fit results suggest that the observations favor a crossing of the phantom divide line.

L. B. Castro

In a recent paper published in this journal, Almeida and collaborators [Phys. Rev. D \textbf{79}, 125022 (2009)] analyze the issue of fermion localization of fermions on a brane constructed from two scalar fields coupled with gravity (Bloch brane model). In this meritorious research the simplest Yukawa coupling $η\barΨϕχΨ$ was considered. In that work does n

Ralf Köhl

Harder&#39;s reduction theory provides filtrations of euclidean buildings that allow one to deduce cohomological and homological properties of S-arithmetic groups over global function fields. In this survey I will sketch the main points of Harder&#39;s reduction theory starting from Weil&#39;s geometry of numbers and the Riemann-Roch theorem, describe a filt

F. Jouve, E. Kowalski, D. Zywina

We discuss rather systematically the principle, implicit in earlier works, that for a &#34;random&#34; element in an arithmetic subgroup of a (split, say) reductive algebraic group over a number field, the splitting field of the characteristic polynomial, computed using any faitfhful representation, has Galois group isomorphic to the Weyl group of the underl

Alejandro Erickson

We provide new evidence that spanning forests of graphs satisfy the same negative correlation properties as spanning trees, derived from Lord Rayleigh&#39;s monotonicity property for electrical networks. The main result of this paper is that the Rayleigh difference for the spanning forest generating polynomial of a series parallel graph can be expressed as a

Patrick Reynolds

We consider the class non-surjective irreducible endomorphisms of the free group $F_n$. We show that such an endomorphism $ϕ$ is topologically represented by a simplicial immersion $f:G \rightarrow G$ of a marked graph $G$; along the way we classify the dynamics of $\partial ϕ$ acting on $\partial F_n$: there are at most $2n$ fixed points, all of which are a

Michael Herrmann, Barbara Niethammer

We derive Kramers' formula as singular limit of the Fokker-Planck equation with double-well potential. The convergence proof is based on the Rayleigh principle of the underlying Wasserstein gradient structure and complements a recent result by Peletier, Savar\'e and Veneroni.

A. A. Grib, Yu. V. Pavlov

The problem of the existence of particles with negative energies inside and outside of Schwarzschild, charged and rotating black holes is investigated. Different definitions of the energy of the particle inside the Schwarzschild black hole are analyzed and it is shown in what cases this energy can be negative. A comparison is made for the cases of rotating b

O. A. Croze

A recent theory by Feigel [Phys. Rev. Lett. {\bf 92}, 020404 (2004)] predicts the finite transfer of momentum from the quantum vacuum to a fluid placed in strong perpendicular electric and magnetic fields. The momentum transfer arises because of the optically anisotropic magnetoelectric response induced in the fluid by the fields. After summarising Feigel&#3

Alexander Braverman, Boris Feigin, Leonid Rybnikov, Michael Finkelberg

Recently Alday, Gaiotto and Tachikawa proposed a conjecture relating 4-dimensional super-symmetric gauge theory for a gauge group G with certain 2-dimensional conformal field theory. This conjecture implies the existence of certain structures on the (equivariant) intersection cohomology of the Uhlenbeck partial compactification of the moduli space of framed

Garvesh Raskutti, Martin J. Wainwright, Bin Yu

Sparse additive models are families of $d$-variate functions that have the additive decomposition $f^* = \sum_{j \in S} f^*_j$, where $S$ is an unknown subset of cardinality $s \ll d$. In this paper, we consider the case where each univariate component function $f^*_j$ lies in a reproducing kernel Hilbert space (RKHS), and analyze a method for estimating the

Tim Leung, Michael Ludkovski

We study the optimal timing of derivative purchases in incomplete markets. In our model, an investor attempts to maximize the spread between her model price and the offered market price through optimally timing her purchase. Both the investor and the market value the options by risk-neutral expectations but under different equivalent martingale measures repr

Steve Butler, Jason Grout

We give a method to construct cospectral graphs for the normalized Laplacian by a local modification in some graphs with special structure. Namely, under some simple assumptions, we can replace a small bipartite graph with a cospectral mate without changing the spectrum of the entire graph. We also consider a related result for swapping out biregular biparti

Charlotte Wahl

We study noncommutative eta- and rho-forms for homotopy equivalences. We prove a product formula for them and show that the rho-forms are well-defined on the structure set. We also define an index theoretic map from L-theory to C*-algebraic K-theory and show that it is compatible with the rho-forms. Our approach, which is based on methods of Hilsum-Skandalis

Jochen Rau

Gibbs states are familiar from statistical mechanics, yet their use is not limited to that domain. For instance, they also feature in the maximum entropy reconstruction of quantum states from incomplete measurement data. Outside the macroscopic realm, however, estimating a Gibbs state is a nontrivial inference task, due to two complicating factors: the prope

Andrey E. Vladimirov, Seth W. Digel, Guðlaugur Jóhannesson, Peter F. Michelson

GALPROP is a numerical code for calculating the galactic propagation of relativistic charged particles and the diffuse emissions produced during their propagation. The code incorporates as much realistic astrophysical input as possible together with latest theoretical developments and has become a de facto standard in astrophysics of cosmic rays. We present

Anzhong Wang

We study cosmological vector and tensor perturbations in Horava-Lifshitz gravity, adopting the most general Sotiriou-Visser-Weinfurtner generalization without the detailed balance but with projectability condition. After deriving the general formulas in a flat FRW background, we find that the vector perturbations are identical to those given in general relat

Koji Ishiwata, Shigeki Matsumoto, Takeo Moroi

We study cosmic-rays in decaying dark matter scenario, assuming that the dark matter is the lightest superparticle and it decays through a R-parity violating operator. We calculate the fluxes of cosmic-rays from the decay of the dark matter and those from the standard astrophysical phenomena in the same propagation model using the GALPROP package. We reevalu

Nathaniel Johnston

We use classical results from the theory of linear preserver problems to characterize operators that send the set of pure states with Schmidt rank no greater than k back into itself, extending known results characterizing operators that send separable pure states to separable pure states. We also provide a new proof of an analogous statement in the multipart

Feng-Kun Guo, Christoph Hanhart, Gang Li, Ulf-G. Meißner

The effects of intermediate charmed mesons on charmonium transitions with the emission of one pion or eta are studied systematically. Based on a non-relativistic effective field theory we show that charmed meson loops are enhanced compared to the corresponding tree-level contributions for transitions between two S-wave charmonia as well as for transitions be

Bruno Iochum, Cyril Levy, Dmitri Vassilevich

We derive a commutative spectral triple and study the spectral action for a rather general geometric setting which includes the (skew-symmetric) torsion and the chiral bag conditions on the boundary. The spectral action splits into bulk and boundary parts. In the bulk, we clarify certain issues of the previous calculations, show that many terms in fact cance