October 2010 arXiv papers — page 2

Changtao Xue, Ximin Liu

Let $X$ be a closed, simply-connected, smooth, spin 4-manifold whose intersection form is isomorphic to $n(-E_8)\bigoplus mH$, where $H$ is the hyperbolic form. In this paper, we prove that for $n$ such that $n\equiv 2 ~{\rm mod} ~4$, there exists a locally linear pseudofree $\mathbb{Z}_2$-action on $X$ which is nonsmoothable with respect to any possible smo

D. Popa, Z. Sun, T. Hasan, F. Torrisi

We demonstrate a wideband-tunable Q-switched fiber laser exploiting a graphene saturable absorber. We get ~2us pulses, tunable between 1522 and 1555nm with up to~40nJ energy. This is a simple and low-cost light source for metrology, environmental sensing and biomedical diagnostics.

Nobuyuki Ishibashi, Koichi Murakami

Light-cone gauge superstring theory in noncritical dimensions corresponds to a worldsheet theory with nonstandard longitudinal part in the conformal gauge. The longitudinal part of the worldsheet theory is a superconformal field theory called X^{\pm} CFT. We show that the X^{\pm} CFT combined with the super-reparametrization ghost system can be described by

Gerard Brunick, Steven Shreve

Given a multi-dimensional Itô process whose drift and diffusion terms are adapted processes, we construct a weak solution to a stochastic differential equation that matches the distribution of the Itô process at each fixed time. Moreover, we show how to match the distributions at each fixed time of functionals of the Itô process, including the running maximu

Julia E. Bergner

In this paper we introduce the models for $(\infty, n)$-categories which have been developed to date, as well as the comparisons between them that are known and conjectured. We review the role of $(\infty, n)$-categories in the proof of the Cobordism Hypothesis.

Vincenzo Savona

We present a systematic numerical approach to compute the eigenmodes and the related eigenfrequencies of a disordered photonic crystal, characterized by small fluctuations of the otherwise periodic dielectric profile. The field eigenmodes are expanded on the basis of Bloch modes of the corresponding periodic structure, and the resulting eigenvalue problem is

Nir Ailon

We study the problem of learning to rank from pairwise preferences, and solve a long-standing open problem that has led to development of many heuristics but no provable results for our particular problem. Given a set $V$ of $n$ elements, we wish to linearly order them given pairwise preference labels. A pairwise preference label is obtained as a response, t

Tom Sanders

Our main result is that if A is a finite subset of an abelian group with |A+A| < K|A|, then 2A-2A contains an O(log^{O(1)} K)-dimensional coset progression M of size at least exp(-O(log^{O(1)} K))|A|.

Ilja Gerhardt, Qin Liu, Antia Lamas-Linares, Johannes Skaar

Quantum key distribution (QKD) allows two remote parties to grow a shared secret key. Its security is founded on the principles of quantum mechanics, but in reality it significantly relies on the physical implementation. Technological imperfections of QKD systems have been previously explored, but no attack on an established QKD connection has been realized

Tom Sanders

We show that if A is a subset of {1,...,N} contains no non-trivial three-term arithmetic progressions then |A|=O(N/ log^{1-o(1)} N). The approach is somewhat different from that used in arXiv:1007.5444.

M. Ando, E. Sharpe

In this paper we use trivial defects to define global taffy-like operations on string worldsheets, which preserve the field theory. We fold open and closed strings on a space X into open strings on products of multiple copies of X, and perform checks that the &#34;taffy-folded&#34; worldsheets have the same massless spectra and other properties as the origin

W. Fischler, W. Tangarife Garcia

We explore how to generate hierarchies in the splittings between superpartners. Some of the consequences are the existence of invisible components of dark matter, new inflaton candidates, invisible monopoles and a number of invisible particles that might dominate during various eras, in particular between BBN and recombination and decay subsequently.

A. Bahri, M. Bendersky, F. R. Cohen, S. Gitler

A combinatorial construction is used to analyze the properties of polyhedral products and generalized moment-angle complexes with respect to certain operations on CW pairs including exponentiation. This allows for the construction of infinite families of toric manifolds, associated to a given one, in a way which simplifies the combinatorial input and consequ

Jean-Daniel Bancal, Nicolas Brunner, Nicolas Gisin, Yeong-Cherng Liang

The structure of Bell-type inequalities detecting genuine multipartite non-locality, and hence detecting genuine multipartite entanglement, is investigated. We first present a simple and intuitive approach to Svetlichny&#39;s original inequality, which provides a clear understanding of its structure and of its violation in quantum mechanics. Based on this ap

Aurélien Deya

By combining the formalism of \cite{RHE} with a discrete approach close to the considerations of \cite{Davie}, we interpret and solve the rough partial differential equation $dy_t=A y_t \, dt+\sum_{i=1}^m f_i(y_t) \, dx^i_t$ ($t\in [0,T]$) on a compact domain $\mathcal{O}$ of $\R^n$, where $A$ is a rather general elliptic operator of $L^p(\mathcal{O})$ ($p>1

Roberto Mainini, David F. Mota

We provide an exhaustive analysis of the Integrated Sach-Wolfe effect (ISW) in the context of coupled Dark Energy cosmologies where a component of massive neutrinos is also present. We focus on the effects of both the coupling between Dark Matter and Dark Energy and of the neutrino mass on the cross-correlation between galaxy/quasar distributions and ISW eff

Andreas M. Menzel, Nigel Goldenfeld

The phenomenon of Coulombic friction enters the stochastic description of dry friction between two solids and the statistic characterization of vibrating granular media. Here we analyze the corresponding Fokker-Planck equation including both velocity and spatial components, exhibiting a formal connection to a quantum mechanical harmonic oscillator in the pre

Agostino Prástaro

In the framework of the PDE&#39;s algebraic topology, previously introduced by A. Prástaro, {\em exotic $n$-d&#39;Alembert PDE&#39;s} are considered. These are $n$-d&#39;Alembert PDE&#39;s, $(d&#39;A)_n$, admitting Cauchy manifolds $N\subset (d&#39;A)_n$ identifiable with exotic spheres, or such that $\partial N$, can be exotic spheres. For such equations lo

Jean Cardinal, Marek Karpinski, Richard Schmied, Claus Viehmann

We study approximability of subdense instances of various covering problems on graphs, defined as instances in which the minimum or average degree is Omega(n/psi(n)) for some function psi(n)=omega(1) of the instance size. We design new approximation algorithms as well as new polynomial time approximation schemes (PTASs) for those problems and establish first

Kh. Saaidi, H. Sheikhahmadi, J. Afzali

Chameleon scalar field is a new model, which introduced to provide a mechanism for exhibiting accelerating universe. Chameleon field has several interesting aspects, such as field dependence on the local matter density. For this model we introduce a new kind of potential which has run away form and satisfies chameleon constraints. The results are acceptable

Hiroyuki Shima, Susanta Ghosh, Marino Arroyo, Kohtaroh Iiboshi

Elastic radial deformation of multiwall carbon nanotubes (MWNTs) under hydrostatic pressure is investigated within the continuum elastic approximation. The thin-shell theory, with accurate elastic constants and interwall couplings, allows us to estimate the critical pressure $p_c$ above which the original circular cross-section transforms into radially corru

Jarno Talponen

We study Banach spaces satisfying some geometric or structural properties involving tightness of transfinite sequences of nested linear subspaces. These properties are much weaker than WCG and closely related to Corson&#39;s property (C). Given a transfinite sequence of normalized vectors, which is dispersed or null in some sense, we extract a subsequence wh

D. Levi, R. I. Yamilov

We present an integrability test for discrete equations on the square lattice, which is based on the existence of a generalized symmetry. We apply this test to a number of equations obtained in different recent papers. As a result we prove the integrability of 7 equations which differ essentially from the $Q_V$ equation introduced by Viallet and thus from th

Madalina Boca, Andreea Oprea

The subject of this paper is the scattering of a very intense laser pulse (intensity $I\sim10^{21}\;{\mathrm{W/cm^2}}$) on relativistic electrons with Lorentz factor between 10 and 45. The laser pulse is modeled by a plane wave with finite length and the calculations are performed within the framework of the classical electrodynamics, which is valid for the

Matteo Luca Ruggiero, Emiliano Capolongo, Angelo Tartaglia

In order to show the principle viability of a recently proposed relativistic positioning method based on the use of pulsed signals from sources at infinity, we present an application example reconstructing the world-line of an idealized Earth in the reference frame of distant pulsars. The method considers the null four-vectors built from the period of the pu

Panayiotis S. Georgiou, Sophia N. Yaliraki, Emmanuel M. Drakakis, Mauricio Barahona

We introduce a mathematical framework for the analysis of the input-output dynamics of externally driven memristors. We show that, under general assumptions, their dynamics comply with a Bernoulli differential equation and hence can be nonlinearly transformed into a formally solvable linear equation. The Bernoulli formalism, which applies to both charge- and

Filippo Giraldi, Francesco Petruccione

The exact dynamics of a Jaynes-Cummings model for a qubit interacting with a continuous distribution of bosons, characterized by a special form of the spectral density, is evaluated analytically. The special reservoir is designed to induce anomalous decoherence, resulting in an inverse power law relaxation, of power 3/2, over an evaluated long time scale. If

M. I. Levchuk

Helicity-dependent incoherent pion photoproduction in the reaction \vec γ\vec d\to πNN is studied in the framework of the diagrammatic approach. Contributions to the reaction amplitude from diagrams corresponding to impulse approximation as well as NN and πN interactions in the final state have been evaluated. The elementary γN\to πN operator is taken from t

M. Yi, D. H. Lu, J. -H. Chu, J. G. Analytis

Nematicity, defined as broken rotational symmetry, has recently been observed in competing phases proximate to the superconducting phase in the cuprate high temperature superconductors. Similarly, the new iron-based high temperature superconductors exhibit a tetragonal to orthorhombic structural transition (i.e. a broken C4 symmetry) that either precedes or

Makoto Yoshida, Masashi Takigawa, Ayako Yamamoto, Hidenori Takagi

We report results of NMR experiments on the ruthenium oxide Hg2Ru2O7 with the pyrochlore structure, which exhibits a metal-insulator transition at TMI = 107 K. In the metallic phase above TMI, the nuclear spin-lattice relaxation rate 1/T1 and the Knight shift at the Hg sites follow the Korringa relation, indicating the absence of substantial spatial spin cor

Xiang-Yao Wu, Bai-Jun Zhang, Jing-Hai Yang, Xiao-Jing Liu

In the paper, we present a new kind of function photonic crystals, which refractive index is a function of space position. Unlike conventional PCs, which structure grow from two materials, A and B, with different dielectric constants $ε_{A}$ and $ε_{B}$. By Fermat principle, we give the motion equations of light in one-dimensional, two-dimensional and three-

Rina Panigrahy

The paper explores known results related to the problem of identifying if a given program terminates on all inputs -- this is a simple generalization of the halting problem. We will see how this problem is related and the notion of proof verifiers. We also see how verifying if a program is terminating involves reasoning through a tower of axiomatic theories

Cyndie Cottrell, Benjamin Young

We present a version of the domino shuffling algorithm (due to Elkies, Kuperberg, Larsen and Propp) which works on a different lattice: the hexagonal lattice superimposed on its dual graph. We use our algorithm to count perfect matchings on a family of finite subgraphs of this lattice whose boundary conditions are compatible with our algorithm. In particular

Douglas Farenick, Tatiana G. Gerasimova, Nadya Shvai

We present necessary and sufficient conditions for an n\times n complex matrix B to be unitarily similar to a fixed unicellular (i.e., indecomposable by similarity) n\times n complex matrix A

Weinan E, Xiang Zhou

Dynamical systems that describe the escape from the basins of attraction of stable invariant sets are presented and analyzed. It is shown that the stable fixed points of such dynamical systems are the index-1 saddle points. Generalizations to high index saddle points are discussed. Both gradient and non-gradient systems are considered. Preliminary results on

Byron Boots, Geoffrey J. Gordon

We propose a new approach to value function approximation which combines linear temporal difference reinforcement learning with subspace identification. In practical applications, reinforcement learning (RL) is complicated by the fact that state is either high-dimensional or partially observable. Therefore, RL methods are designed to work with features of st

R. Trotta, G. Johannesson, I. V. Moskalenko, T. A. Porter

Research in many areas of modern physics such as, e.g., indirect searches for dark matter and particle acceleration in SNR shocks, rely heavily on studies of cosmic rays (CRs) and associated diffuse emissions (radio, microwave, X-rays, gamma rays). While very detailed numerical models of CR propagation exist, a quantitative statistical analysis of such model

B. D. Johnson, J. P. Crutchfield, C. J. Ellison, C. S. McTague

We show how to efficiently enumerate a class of finite-memory stochastic processes using the causal representation of epsilon-machines. We characterize epsilon-machines in the language of automata theory and adapt a recent algorithm for generating accessible deterministic finite automata, pruning this over-large class down to that of epsilon-machines. As an

A. A. Rangelov, H. Suchowski, Y. Silberberg, N. V. Vitanov

We propose a technique for efficient mid-range wireless power transfer between two coils, by adapting the process of adiabatic passage for a coherently driven two-state quantum system to the realm of wireless energy transfer. The proposed technique is shown to be robust to noise, resonant constraints, and other interferences that exist in the neighborhood of

M. Emre Celebi, Hitoshi Iyatomi, Gerald Schaefer, William V. Stoecker

Background: Dermoscopy is one of the major imaging modalities used in the diagnosis of melanoma and other pigmented skin lesions. Due to the difficulty and subjectivity of human interpretation, computerized analysis of dermoscopy images has become an important research area. One of the most important steps in dermoscopy image analysis is the automated detect

Gia Dvali, David Pirtskhalava

We study dynamics of the classicalization phenomenon suggested in arXiv:1010.1415, according to which a class of non-renormalizable theories self-unitarizes at high-energies via creation of classical configurations (classicalons). We study this phenomenon in an explicit model of derivatively-self-coupled scalar that serves as a prototype for a Nambu-Goldston

P. Afonso, J. Greiner, E. Pian, S. Covino

Aims: GRB 050502B is well known for the very bright flare displayed in its X-ray light curve. Despite extensive studies, however, the optical light curve has never been discussed and its redshift is unconstrained. Possible correlations between optical and X-ray data are analysed. Methods: Photometric data from TNG in the R and I bands were used to compare th

M. P. Jura, M. Grobis, M. A. Topinka, L. N. Pfeiffer

Using scanning gate microscopy (SGM), we probe the scattering between a beam of electrons and a two-dimensional electron gas (2DEG) as a function of the beam&#39;s injection energy, and distance from the injection point. At low injection energies, we find electrons in the beam scatter by small-angles, as has been previously observed. At high injection energi

Martin Goldman, Giovanni Lapenta, David Newman, Stefan Markidis

Simulations of antiparallel reconnection have shown collimated electron jets outflowing from the x-point, and associated highly elongated &#34;outer electron diffusion regions.&#34; New PIC simulations with ion/electron mass ratios as large as 1836 show that jets are deflected towards the magnetic separatrix by out-of-plane guide fields, Bg, as small as 0.05

Takashi Tsukagoshi, Masao Saito, Yoshimi Kitamura, Munetake Momose

We present the discovery of a cold massive dust disk around the T Tauri star V1094 Sco in the Lupus molecular cloud from the 1.1 millimeter continuum observations with AzTEC on ASTE. A compact ($r\lesssim$320 AU) continuum emission coincides with the stellar position having a flux density of 272 mJy which is largest among T Tauri stars in Lupus. We also pres

Paul S. Wesson

Astronomically, there are viable mechanisms for distributing organic material throughout the Milky Way. Biologically, the destructive effects of ultraviolet light and cosmic rays means that the majority of organisms arrive broken and dead on a new world. The likelihood of conventional forms of panspermia must therefore be considered low. However, the informa

Till Mossakowski, Reinhard Moratz

An important issue in Qualitative Spatial Reasoning is the representation of relative direction. In this paper we present simple geometric rules that enable reasoning about relative direction between oriented points. This framework, the Oriented Point Algebra OPRA_m, has a scalable granularity m. We develop a simple algorithm for computing the OPRA_m composi

Katya Scheinberg, Shiqian Ma, Donald Goldfarb

Gaussian graphical models are of great interest in statistical learning. Because the conditional independencies between different nodes correspond to zero entries in the inverse covariance matrix of the Gaussian distribution, one can learn the structure of the graph by estimating a sparse inverse covariance matrix from sample data, by solving a convex maximu

Matthieu Cornec

In this article, we derive concentration inequalities for the cross-validation estimate of the generalization error for empirical risk minimizers. In the general setting, we prove sanity-check bounds in the spirit of \cite{KR99} \textquotedblleft\textit{bounds showing that the worst-case error of this estimate is not much worse that of training error estimat

Jens Langelage, Stefano Lottini, Owe Philipsen

Lattice Yang-Mills theories at finite temperature can be mapped onto effective 3d spin systems, thus facilitating their numerical investigation. Using strong-coupling expansions we derive effective actions for Polyakov loops in the $SU(2)$ and $SU(3)$ cases and investigate the effect of higher order corrections. Once a formulation is obtained which allows fo

M. Emre Celebi

Color quantization is an important operation with numerous applications in graphics and image processing. Most quantization methods are essentially based on data clustering algorithms. However, despite its popularity as a general purpose clustering algorithm, k-means has not received much respect in the color quantization literature because of its high compu

Yanyan Li, Dario Daniele Monticelli

In this paper we provide a characterization of second order fully nonlinear CR invariant equations on the Heisenberg group, which is the analogue in the CR setting of the result proved in the Euclidean setting by A. Li and the first author (2003). We also prove a comparison principle for solutions of second order fully nonlinear CR invariant equations define

LAT collaboration

We report on the search for 0.1-10 GeV emission from magnetars in 17 months of Fermi Large Area Telescope (LAT) observations. No significant evidence for gamma-ray emission from any of the currently-known magnetars is found. The most stringent upper limits to date on their persistent emission in the Fermi-LAT energy range are estimated between ~10^{-12}-10^{

N. Kamaraju, Sunil Kumar, M. Anija, A. K. Sood

We report femtosecond time-resolved reflectivity measurements of coherent phonons in tellurium performed over a wide range of temperatures (3K to 296K) and pump laser intensities. A totally symmetric A$_{1}$ coherent phonon at 3.6 THz responsible for the oscillations in the reflectivity data is observed to be strongly positively chirped (i.e, phonon time per

François Molino, Pierre Rognon, Cyprien Gay

When deformed, liquid foams tend to raise their liquid contents like immersed granular materials, a phenomenon called dilatancy. We have aready described a geometrical interpretation of elastic dilatancy in 3D foams and in very dry foams squeezed between two solid plates (2D GG foams). Here, we complement this work in the regime of less dry 2D GG foams. In p

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

The strong coupling constants of heavy baryons with light vector mesons are calculated in the framework of the light cone QCD sum rules using the most general form of the interpolating currents for the heavy baryons. It is shown that the sextet--sextet, sextet--antitriplet and antitriplet--antitriplet transitions are described by one invariant function for e

Peter Haissinsky, Kevin M. Pilgrim

In previous work, a class of noninvertible topological dynamical systems $f: X \to X$ was introduced and studied; we called these {\em topologically coarse expanding conformal} systems. To such a system is naturally associated a preferred quasisymmetry (indeed, snowflake) class of metrics in which arbitrary iterates distort roundness and ratios of diameters

Kumar Abhinav, Prasanta K. Panigrahi

Dynamical systems exhibiting both PT and Supersymmetry are analyzed in a general scenario. It is found that, in an appropriate parameter domain, the ground state may or may not respect PT-symmetry. Interestingly, in the domain where PT-symmetry is not respected, two superpotentials give rise to one potential; whereas when the ground state respects PT, this c

Victor Snaith

In the local, unramified case the determinantal functions associated to the group-ring of a finite group satisfy Galois descent. This note examines the obstructions to Galois determinantal descent in the ramified case.

Georgi Dimov, Elza Ivanova

In 1962, H. de Vries proved a duality theorem for the category {\bf HC} of compact Hausdorff spaces and continuous maps. The composition of the morphisms of the dual category obtained by him differs from the set-theoretic one. Here we obtain a new category dual to the category {\bf HLC} of locally compact Hausdorff spaces and continuous maps for which the co

John Ellis

The prospects for detecting a candidate supersymmetric dark matter particle at the LHC are reviewed, and compared with the prospects for direct and indirect searches for astrophysical dark matter, on the basis of a frequentist analysis of the preferred regions of the Minimal supersymmetric extension of the Standard Model with universal soft supersymmetry bre

Kieren MacMillan, Jonathan Sondow

A frequently cited theorem says that for n > 0 and prime p, the sum of the first p n-th powers is congruent to -1 modulo p if p-1 divides n, and to 0 otherwise. We survey the main ingredients in several known proofs. Then we give an elementary proof, using an identity for power sums proven by Pascal in 1654. An application is a simple proof of a congruence f

Rakhsha Nasseripour, Barry Berman, the CLAS Collaboration

We have measured the differential cross section for the $γ$$^3$He$\rightarrow π^+ t$ reaction. This reaction was studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Real photons produced with the Hall-B bremsstrahlung tagging system in the energy range from 0.50 to 1.55 GeV were incident on a cryogenic liquid $^3$He target. The dif

Clark Butler, Sergei Chmutov

We establish a relation between the Bollobas-Riordan polynomial of a ribbon graph with the relative Tutte polynomial of a plane graph obtained from the ribbon graph using its projection to the plane in a nontrivial way. Also we give a duality formula for the relative Tutte polynomial of dual plane graphs and an expression of the Kauffman bracket of a virtual

Jack Morava

In the first part of this note, we show (following Hofbauer and Sigmund) that Dawkins&#39; &#34;Battle of the Sexes&#34; defines an interesting map from a space of economic parameters to psychosocial coordinates. The second part discusses an even more elementary game, but one which is not completely trivial.

C. Scimiterna, D. Levi

In this article we discuss a series of models introduced by Barashenkov, Oxtoby and Pelinovsky to describe some discrete approximations to the ϕ^4 theory which preserve travelling kink solutions. We show, by applying the multiple scale test that they have some integrability properties as they pass the A_1 and A_2 conditions. However they are not integrable a

Matyas Barczy, Peter Kern

We derive bridges from general multidimensional linear non time-homogeneous processes using only the transition densities of the original process giving their integral representations (in terms of a standard Wiener process) and so-called anticipative representations. We derive a stochastic differential equation satisfied by the integral representation and we

S. Nadj-Perge, S. M. Frolov, E. P. A. M. Bakkers, L. P. Kouwenhoven

Motion of electrons can influence their spins through a fundamental effect called spin-orbit interaction. This interaction provides a way to electrically control spins and as such lies at the foundation of spintronics. Even at the level of single electrons, spin-orbit interaction has proven promising for coherent spin rotations. Here we report a spin-orbit q

Zheng Ran

The central problem of fully developed turbulence is the energy cascading process. It has revisited all attempts at a full physical understanding or mathematical formulation. The main reason for this failure are related to the large hierarchy of scales involved, the highly nonlinear character inherent in the Navier-Stokes equations, and the spatial intermitt

Debdeep Jena, John Simon, Albert, Wang

The role of spontaneous and piezoelectric polarization in III-V nitride heterostructure devices is discussed. Problems as well as opportunities in incorporating polarization in abrupt and graded heterojunctions composed of binary, ternary, and quaternary nitrides are outlined.

Gerard &#39;t Hooft

Perturbative canonical quantum gravity is considered, when coupled to a renormalizable model for matter fields. It is proposed that the functional integral over the dilaton field should be disentangled from the other integrations over the metric fields. This should generate a conformally invariant theory as an intermediate result, where the conformal anomali

Luke Bornn, Julien Cornebise, Gareth W. Peters

This technical report is the union of two contributions to the discussion of the Read Paper &#34;Riemann manifold Langevin and Hamiltonian Monte Carlo methods&#34; by B. Calderhead and M. Girolami, presented in front of the Royal Statistical Society on October 13th 2010 and to appear in the Journal of the Royal Statistical Society Series B. The first comment

M. Pepe

We study some features of the confining string connecting a quark-anti-quark pair in Yang-Mills theory. Monte Carlo investigations of the flux tube between two static quarks in the fundamental representation show that its thickness increases with the separation of the sources. The collected numerical data in (2+1)-d SU(2) Yang-Mills theory are in very good q

Tiamhock Tay, Olexei I. Motrunich

We investigate a hard-core boson model with ring-only exchanges on a square lattice, where a $K_1$ term acts on 1$\times$1 plaquettes and a $K_2$ term acts on 1$\times$2 and 2$\times$1 plaquettes, with a goal of realizing a novel Exciton Bose Liquid (EBL) phase first proposed by Paramekanti, et al [Phys. Rev. B {\bf 66}, 054526 (2002)]. We construct Jastrow-

Clément de Seguins Pazzis

In a previous paper, we have constructed, for an arbitrary Lie group G and any of the fields F=R or C, a good equivariant cohomology theory KF_G^*(-) on the category of proper $G$-CW-complex and have justified why it deserved the label ``equivariant K-theory&#34;. It was shown in particular how this theory was a logical extension of the construction of Lück

Clément de Seguins Pazzis

Generalizing a construction of Wolfgang Lück and Bob Oliver, we define a good equivariant cohomology theory on the category of proper G-CW complexes when G is an arbitrary Lie group (possibly non-compact). This is done by constructing an appropriate classifying space that arises from a Gamma-G-space. It is proven that this theory effectively generalizes Sega

Yuan Yuan, David A. Neufeld

We have studied the shock-excited molecular regions associated with four supernova remnants (SNRs) - IC443C, W28, W44 and 3C391 - and two Herbig-Haro objects, HH7 and HH54, using Spitzer&#39;s Infrared Spectrograph (IRS). The physical conditions within the observed areas are inferred from spectroscopic data obtained from IRS and from SWS and LWS onboard ISO,

Gabriel Ciobanu, Maciej Koutny

The 4th Workshop on Membrane Computing and Biologically Inspired Process Calculi (MeCBIC 2010) is organized in Jena as a satellite event of the Eleventh International Conference on Membrane Computing (CMC11). Biological membranes play a fundamental role in the complex reactions which take place in cells of living organisms. The importance of this role has be

Takashi Miyasaka

A Lie group $G$ naturally acts on its Lie algebra $\gg$, called the adjoint action. In this paper, we determine the orbit types of the compact exceptional Lie group $G_2$ in its Lie algebra $\gg_2$. As results, the group $G_2$ has four orbit types in the Lie algebra $\gg_2$ as $$ G_2/G_2, \quad G_2/(U(1) \times U(1)), \quad G_2/((Sp(1)\times U(1))/\Z_2), \qu

Jian Wen Dong, Hui Huo Zheng, Yun Lai, He Zhou Wang

We show that a metamaterial slab with arbitrary values of epsilon and mu behaves as a cloak at a finite frequency for a small object located sufficiently close to it due to the suppression of the object&#39;s optical excitations by enhanced reflections. Reflections due to propagating components can partially suppress the excitation while evanescent component

Douglas Farenick, Vyacheslav Futorny, Tatiana G. Gerasimova, Vladimir V. Sergeichuk

Each square complex matrix is unitarily similar to an upper triangular matrix with diagonal entries in any prescribed order. Let A and B be upper triangular n-by-n matrices that (i) are not similar to direct sums of matrices of smaller sizes, or (ii) are in general position and have the same main diagonal. We prove that A and B are unitarily similar if and o

Oriane Bonhomme, Alexander Morozov, Jacques Leng, Annie Colin

We study experimentally the interfacial instability between a layer of dilute polymer solution and water flowing in a thin capillary. The use of microfluidic devices allows us to observe and quantify in great detail the features of the flow. At low velocities, the flow takes the form of a straight jet, while at high velocities, steady or advected wavy jets a

Alexander Perry

We give a self-contained exposition of the proof of faithfully flat descent for projectivity of modules. This fills a gap in the proof given in the literature.

Yusuke Nishida, Shina Tan

We show that a purely s-wave interaction in three dimensions (3D) can induce higher partial-wave resonances in mixed dimensions. We develop two-body scattering theories in all three cases of 0D-3D, 1D-3D, and 2D-3D mixtures and determine the positions of higher partial-wave resonances in terms of the 3D s-wave scattering length assuming a harmonic confinemen

Kaden R. A. Hazzard, Victor Gurarie, Michael Hermele, Ana Maria Rey

We calculate experimentally relevant properties of trapped fermionic alkaline earth atoms in an optical lattice, modeled by the SU(N) Hubbard model. Our calculation is accurate when the temperature is much larger than the tunneling rate, similar to current regimes in ultracold atom experiments. In addition to exploring the Mott insulator-metal crossover, we

Piet Groeneboom

It was shown in Groeneboom (1983) that the least concave majorant of one-sided Brownian motion without drift can be characterized by a jump process with independent increments, which is the inverse of the process of slopes of the least concave majorant. This result can be used to prove the result of Sparre Andersen (1954) that the number of vertices of the s

Rohit Aggarwal, Mohamad Assaad, C. Emre Koksal, Philip Schniter

We consider the problem of simultaneous user-scheduling, power-allocation, and rate-selection in an OFDMA downlink, with the goal of maximizing expected sum-utility under a sum-power constraint. In doing so, we consider a family of generic goodput-based utilities that facilitate, e.g., throughput-based pricing, quality-of-service enforcement, and/or the trea

E. M. C. Abreu, R. Amorim, W. Guzmán Ramírez

We present a formulation in a curved background of noncommutative mechanics, where the object of noncommutativity $θ^{μν}$ is considered as an independent quantity having a canonical conjugate momentum. We introduced a noncommutative first-order action in D=10 curved spacetime and the covariant equations of motions were computed. This model, invariant under

Lilian Matthiesen

In this paper we study linear correlations of the divisor function tau(n) = sum_{d|n} 1 using methods developed by Green and Tao. For example, we obtain an asymptotic for sum_{n,d} tau(n) tau(n+d) ... tau(n+ (k-1)d).

Thomas E. Markland, Joseph A. Morrone, B. J. Berne, Kunimasa Miyazaki

The very nature of glass is somewhat mysterious: while relaxation times in glasses are of sufficient magnitude that large-scale motion on the atomic level is essentially as slow as it is in the crystalline state, the structure of glass appears barely different than that of the liquid that produced it. Quantum mechanical systems ranging from electron liquids

Noson S. Yanofsky

Many different programs are the implementation of the same algorithm. The collection of programs can be partitioned into different classes corresponding to the algorithms they implement. This makes the collection of algorithms a quotient of the collection of programs. Similarly, there are many different algorithms that implement the same computable function.

Mads T. Frandsen, Isabella Masina, Francesco Sannino

We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how they can be used to predict the positron fraction at energies not yet explored by current experiments and to constrain specific models.

David MacNeill, Fei Zhou

In this Letter we study the effect of Pauli blocking on the Efimov states in a quantum Fermi gas and illustrate that the universal Efimov potential is altered at large distances. We obtain the universal spectrum flow of Efimov trimers when the Fermi density is varied and further consider the effect of scattering of trimers by the Fermi sea. We argue that the

Michael J. Mortonson, Wayne Hu, Dragan Huterer

Observation of even a single massive cluster, especially at high redshift, can falsify the standard cosmological framework consisting of a cosmological constant and cold dark matter (LCDM) with Gaussian initial conditions by exposing an inconsistency between the well-measured expansion history and the growth of structure it predicts. Through a likelihood ana

Yuk Tung Liu, Stuart L. Shapiro

Tidal torques acting on a gaseous accretion disk around a binary black hole can create a gap in the disk near the orbital radius. At late times, when the binary inspiral timescale due to gravitational wave emission becomes shorter than the viscous timescale in the disk, the binary decouples from the disk and eventually merges. Prior to decoupling the balance

Sakura Schafer-Nameki, Carlos Tamarit, Gonzalo Torroba

Postulating that the NMSSM singlet is a meson of a microscopic confining theory opens up new model-building possibilities. Based on this, we construct calculable models of direct mediation that solve the mu/Bmu problem and simultaneously lead to realistic phenomenology. The singlet that couples to the Higgs fields develops a runaway produced by soft interact

Céline Degrande, Jean-Marc Gérard, Christophe Grojean, Fabio Maltoni

We use top quark pair production as a probe of top-philic non-resonant new physics. Following a low energy effective field theory approach, we calculate several key observables in top quark pair production at hadron colliders (e.g., total cross section, ttbar invariant mass distribution, forward-backward asymmetry, spin correlations) including the interferen

Dominic W. Berry, A. I. Lvovsky

We propose a measure of quantum efficiency of a multimode state of light that quantifies the amount of optical loss this state has experienced, and prove that this efficiency cannot increase in any linear-optical processing with destructive conditional measurements. Any loss that has affected a state can neither be removed nor redistributed so as to further

Ivan Booth, Michal P. Heller, Michal Spalinski

A generalization of entropy to near-equilibrium phenomena is provided by the notion of a hydrodynamic entropy current. Recent advances in holography have lead to the formulation of fluid-gravity duality, a remarkable connection between the hydrodynamics of certain strongly coupled media and dynamics of higher dimensional black holes. This Letter introduces a

Dan M. Barbasch, Peter E. Trapa

The set of special unipotent representations of a semisimple Lie group was defined by Barbasch and Vogan. According to predictions of Arthur (established by Adams, Barbasch, and Vogan), this set is an overlapping union of Arthur packets. Each packet gives rise to a canonical virtual representation whose character is stable in the sense of Langlands and Shels