July 2009 arXiv papers — page 3

T. J. Carroll, C. Daniel, L. Hoover, T. Sidie

The dipole-dipole interaction among ultra-cold Rydberg atoms is simulated. We examine a general interaction scheme in which two atoms excited to the x and x' states are converted to y and y' states via a Forster resonance. The atoms are arranged in two spatially separated groups, each consisting of only one species of atom. We record the fraction of

Łukasz Rajchel, Piotr S. Żuchowski, Małgorzata M. Szcześniak, Grzegorz Chałasiński

We propose a "DFT+dispersion" treatment which avoids double counting of dispersion terms by deriving the dispersion-free density functional theory (DFT) interaction energy and combining it with DFT-based dispersion. The formalism involves self-consistent polarization of DFT monomers restrained by the exclusion principle via the Pauli blockade techniq

Libby Heaney, Vlatko Vedral

Natural particle-number entanglement resides between spatial modes in coherent ultra-cold atomic gases. However, operations on the modes are restricted by a superselection rule that forbids coherent superpositions of different particle numbers. This seemingly prevents mode entanglement being used as a resource for quantum communication. In this paper, we dem

Niayesh Afshordi

A proposal for a power-counting renormalizable theory of quantum gravity at a Lifshitz point was recently put forth by Horava (arXiv:0901.3775), and has been since dubbed as Horava-Lifshitz gravity. The theory explicitly breaks Lorentz invariance, which introduces an apparent extra scalar degree of freedom. In this note, we show that the low energy limit of

Claus Gerhardt

We prove the existence of a spectral resolution of the Wheeler-DeWitt equation when the matter field is provided by a Yang-Mills field, with or without mass term, if the spatial geometry of the underlying spacetime is homothetic to $\R[3]$. The energy levels of the resulting quantum model, i.e., the eigenvalues of the corresponding self-adjoint Hamiltonian w

Juan Jose Jaramillo, R. Srikant

This paper studies the problem of congestion control and scheduling in ad hoc wireless networks that have to support a mixture of best-effort and real-time traffic. Optimization and stochastic network theory have been successful in designing architectures for fair resource allocation to meet long-term throughput demands. However, to the best of our knowledge

Christopher Gordon, Jonathan R. Pritchard

A "compensated" isocurvature perturbation consists of an overdensity (or underdensity) in the cold dark matter which is completely cancelled out by a corresponding underdensity (or overdensity) in the baryons. Such a configuration may be generated by a curvaton model of inflation if the cold dark matter is created before curvaton decay and the baryon

Mengxing Cheng, Matthew T. Glossop, Kevin Ingersent

We study the competition between Kondo physics and dissipation within an Anderson model of a magnetic impurity level that hybridizes with a metallic host and is also coupled, via the impurity charge, to the displacement of a bosonic bath having a spectral density proportional to ω^s. As the impurity-bath coupling increases from zero, the effective Coulomb in

Divyanshu Vats, Jose M. F. Moura

We present \emph{telescoping} recursive representations for both continuous and discrete indexed noncausal Gauss-Markov random fields. Our recursions start at the boundary (a hypersurface in $\R^d$, $d \ge 1$) and telescope inwards. For example, for images, the telescoping representation reduce recursions from $d = 2$ to $d = 1$, i.e., to recursions on a sin

Rahul Nandkishore, Leonid Levitov

Electron interactions in undoped bilayer graphene lead to instability of the gapless state, `which-layer' symmetry breaking, and energy gap opening at the Dirac point. In contrast to single layer graphene, the bilayer system exhibits instability even for arbitrarily weak interaction. A controlled theory of this instability for realistic dynamically scree

Fulvio Melia, Majd Abdelqader

We present here the transformations required to recast the Robertson-Walker metric and Friedmann-Robertson-Walker equations in terms of observer-dependent coordinates for several commonly assumed cosmologies. The overriding motivation is the derivation of explicit expressions for the radius R_h of our cosmic horizon in terms of measurable quantities for each

Jean Bellissard, Charles Radin, Senya Shlosman

We consider limits of equilibrium distributions as temperature approaches zero, for systems of infinitely many particles, and characterize the support of the limiting distributions. Such results are known for particles with positions on a fixed lattice; we extend these results to systems of particles on R^n, with restrictions on the interaction.

Daniel Feldman, Zuowei Liu, Pran Nath, Brent D. Nelson

The PAMELA positron excess is analyzed within the framework of nonuniversal SUGRA models with an extended $U(1)^n$ gauge symmetry in the hidden sector leading to neutralino dark matter with either a mixed Higgsino-wino LSP or an essentially pure wino dominated LSP. The Higgsino-wino LSP can produce the observed PAMELA positron excess and satisfy relic densit

Javier Virto

We compute the order alpha_s^3 (next-to-leading) corrections to the Wilson coefficients of the Delta F=2 effective Hamiltonian in the Minimal Supersymmetric Standard Model with completely arbitrary soft terms. These results are relevant for phenomenological studies of neutral meson mixings in the presence of large squark mass splittings, in particular in hie

Cédric Bény, Ognyan Oreshkov

We derive necessary and sufficient conditions for the approximate correctability of a quantum code, generalizing the Knill-Laflamme conditions for exact error correction. Our measure of success of the recovery operation is the worst-case entanglement fidelity of the overall process. We show that the optimal recovery fidelity can be predicted exactly from a d

Junji Jia

The neutrino masses and oscillation are closely related to how neutrino propagates. In this paper, we first derive a new form of four-momentum conservation that connects the four-momentum $(E_α,~p_α)$ of the neutrino flavor eigenstate and the four momenta $(E_i,~p_i)$ of its mass eigen-components. Then we use the assumption that the mass eigen-components tra

G. E. Volovik

Superfluid 3He-B belongs to the important special class of time-reversal invariant topological superfluids. It has Majorana fermions as edge states on the surface of bulk 3He-B. On the rough wall these fermion zero modes have finite density of states at E=0. It is possible that Lancaster experiments with a wire vibrating in 3He-B have already probed Majorana

Guido Mueller, Pierre Sikivie, D. B. Tanner, Karl van Bibber

A resonantly-enhanced photon-regeneration experiment to search for the axion or axion-like particles is described. This experiment is a shining light through walls study, where photons travelling through a strong magnetic field are (in part) converted to axions; the axions can pass through an opaque wall and convert (in part) back to photons in a second regi

J. Ross, R. P. Thomas

We describe a notion of ampleness for line bundles on orbifolds with cyclic quotient singularities that is related to embeddings in weighted projective space, and prove a global asymptotic expansion for a weighted Bergman kernel associated to such a line bundle.

Yuji Shirasaki, Masahiro Tanaka, Masatoshi Ohishi, Yoshihiko Mizumoto

We present the result of projected cross correlation analysis of AGNs and galaxies at redshifts from 0.3 to 3.0. The Japanese Virtual Observatory (JVO) was used to obtain the Subaru Suprime-Cam images and UKIDSS catalog data around AGNs. We investigated 1,809 AGNs, which is about ten times larger a sample than that used in previous studies on AGN-galaxy clus

A. Cavalleri, G. Ciani, R. Dolesi, M. Hueller

We present a simple analysis of the force noise associated with the mechanical damping of the motion of a test body surrounded by a large volume of rarefied gas. The calculation is performed considering the momentum imparted by inelastic collisions against the sides of a cubic test mass, and for other geometries for which the force noise could be an experime

J. González-Meneses, P. M. G. Manchón

Let D be a link diagram with n crossings, s_A and s_B its extreme states and |s_AD| (resp. |s_BD|) the number of simple closed curves that appear when smoothing D according to s_A (resp. s_B). We give a general formula for the sum |s_AD|+|s_BD| for a k-almost alternating diagram D, for any k, characterising this sum as the number of faces in an appropriate t

Ward Struyve

In 1952 Bohm presented a theory about non-relativistic point-particles moving along deterministic trajectories and showed how it reproduces the predictions of standard quantum theory. This theory was actually presented before by de Broglie in 1926, but Bohm's particular formulation of the theory inspired Epstein to come up with a different trajectory mod

The HERMES Collaboration, A. Airapetian

The transverse-target single-spin asymmetry for inclusive deep-inelastic scattering with effectively unpolarized electron and positron beams off a transversely polarized hydrogen target was measured, with the goal of searching for a two-photon exchange signal in the kinematic range 0.007 < x_B < 0.9 and 0.25 GeV**2 < Q**2 < 20 GeV**2. In two separate regions

Eilam Gross, Ofer Vitells

Charged Higgs boson may be produced at hadron colliders via the decay of top quarks. At the LHC, The large production cross section of top quarks pairs will make it one of the earliest channels allowing to search for physics beyond the standard model. Assuming the decay $H^+ \to τ^+ν$, previous searches have so far considered only hadronic tau decays. Here w

Daniel Müllner

We call a closed, connected, orientable manifold in one of the categories TOP, PL or DIFF chiral if it does not admit an orientation-reversing automorphism and amphicheiral otherwise. Moreover, we call a manifold strongly chiral if it does not admit a self-map of degree -1. We prove that there are strongly chiral, smooth manifolds in every oriented bordism c

Jan Lorenz, Stefano Battiston, Frank Schweitzer

We introduce a general framework for models of cascade and contagion processes on networks, to identify their commonalities and differences. In particular, models of social and financial cascades, as well as the fiber bundle model, the voter model, and models of epidemic spreading are recovered as special cases. To unify their description, we define the net

D. N. Basu, P. Roy Chowdhury, C. Samanta

The isospin dependence of the saturation properties of asymmetric nuclear matter, particularly the incompressibility $K_\infty (X) = K_\infty + K_τX^2 + O(X^4)$ at saturation density is systematically studied using density dependent M3Y interaction. The $K_τ$ characterizes the isospin dependence of the incompressibility at saturation density $ρ_0$. The appro

Clément de Seguins Pazzis

We study which matrices are sums of idempotents over a field of non-zero characteristic; in particular, we prove that any such matrix, provided it is large enough, is actually a sum of five idempotents, and even of four when the field is a prime one.

K. Hicks, A. Daniel

The hadronization of $K^0$ particles was measured in semi-inclusive deep inelastic scattering (SIDIS) kinematics for several nuclear targets using the CLAS detector. Multiplicity ratios and $\Delta p_T^2$ values were extracted from the data. These results may be compared with similar values for $\pi^+$ hadronization from CLAS (at the same kinematics) and $K^

Joan A. Cabrer, Gero von Gersdorff, Mariano Quiros

We propose a general class of five-dimensional soft-wall models with AdS metric near the ultraviolet brane and four-dimensional Poincaré invariance, where the infrared scale is determined dynamically. A large UV/IR hierarchy can be generated without any fine-tuning, thus solving the electroweak/Planck scale hierarchy problem. Generically, the spectrum of flu

André de Laire

We study the Gross-Pitaevskii equation involving a nonlocal interaction potential. Our aim is to give sufficient conditions that cover a variety of nonlocal interactions such that the associated Cauchy problem is globally well-posed with non-zero boundary condition at infinity, in any dimension. We focus on even potentials that are positive definite or posit

Christof Roland

Studies of heavy-ion collisions at the LHC will benefit from an array of qualitatively new probes not readily available at lower collision energies. These include fully formed jets at ET > 50 GeV, Z0's and abundantly produced heavy flavors. For Pb+Pb running at LHC design luminosity, the collision rate in the CMS interaction region will exceed the available

Souvik Ghosh, Sidney I Resnick

A widely used tool in the study of risk, insurance and extreme values is the mean excess plot. One use is for validating a generalized Pareto model for the excess distribution. This paper investigates some theoretical and practical aspects of the use of the mean excess plot.

Chuan-Tsung Chan, Wei-Ming Chen

A systematic scheme is developed for solving conformal algebra of the massive vertex operators in the old covariant first quantized string theory. Using the first massive level in the covariant spectrum of bosonic open string theory in flat space-time as an example, we explicitly verify the conformal algebra for the normal-ordered covariant vertex operator.

M. Thøgersen, N. T. Zinner, A. S. Jensen

We consider the ground state of a harmonically trapped Bose-Einstein condensate within the Gross-Pitaevskii theory including the effective-range corrections for a two-body zero-range potential. The resulting non-linear Schrödinger equation is solved analytically in the Thomas-Fermi approximation neglecting the kinetic energy term. We present results for the

Kohei Tanaka

We define a new model structure on the category of small categories, which is intimately related to the notion of coverings and fundamental groups of small categories. Fibrant objects in the model structure coincide with groupoids, and the fibrant replacement is the groupoidification.

M. Scala, R. Migliore, A. Messina, L. L. Sanchez-Soto

The dissipative dynamics of two interacting qubits coupled to independent reservoirs at nonzero temperatures is investigated, paying special attention to the entanglement evolution. The counter-rotating terms in the qubit-qubit interaction give rise to stationary entanglement, traceable back to the ground state structure. The robustness of this entanglement

Weimin Chen

This paper initiated an investigation on the following question: Suppose a smooth 4-manifold does not admit any smooth circle actions. Does there exist a constant $C>0$ such that the manifold support no smooth $\Z_p$-actions of prime order for $p>C$? We gave affirmative results to this question for the case of holomorphic and symplectic actions, with an inte

Liang Cai, Frank Hansen

We give a truly elementary proof of the convexity of metric adjusted skew information following an idea of Effros. We extend earlier results of weak forms of superadditivity to general metric adjusted skew informations. Recently, Luo and Zhang introduced the notion of semi-quantum states on a bipartite system and proved superadditivity of the Wigner-Yanase-D

Moritz Kerz

We propose a notion of idele class groups of finitely generated fields using the concept of Parshin chains. This new class group allows us to give an idelic interpretation of the higher class field theory of Kato and Saito.

V. S. Mikhailenko, V. V. Mikhailenko, K. N. Stepanov

The linear and renormalized nonlinear analysis of the temporal evolution of drift-type modes in plasma flows with strong time-varying velocity shear is developed. Analysis is performed in the time domain without spectral decomposition in time and admits time variation of the flow velocity with time scales which may be comparable with turbulent time scales. 5

Ashok Das, J. Frenkel

We present, from first principles, a direct method for evaluating the exact fermion propagator in the presence of a general background field at finite temperature, which can be used to determine the finite temperature effective action for the system. As applications, we determine the complete one loop finite temperature effective actions for 0+1 dimensional

Tapio Helin

In this article, the solution of a statistical inverse problem $M = AU+\mathcal{E}$ by the Bayesian approach is studied where $U$ is a function on the unit circle $\mathbb{T}$, i.e., a periodic signal. The mapping $A$ is a smoothing linear operator and $\mathcal{E}$ a Gaussian noise. The connection to the solution of a finite-dimensional computational model

Thomas Baier, José M. Mourão, João P. Nunes

We study the dependence of geometric quantization of the standard symplectic torus on the choice of invariant polarization. Real and mixed polarizations are interpreted as degenerate complex structures. Using a weak version of the equations of covariant constancy, and the Weil-Brezin expansion to describe distributional sections, we give a unified analytical

Tomoya Sakai

A robust classification method is developed on the basis of sparse subspace decomposition. This method tries to decompose a mixture of subspaces of unlabeled data (queries) into class subspaces as few as possible. Each query is classified into the class whose subspace significantly contributes to the decomposed subspace. Multiple queries from different class

Carla Bosia, Michele Caselle, Davide Corá

The aim of our work is to study the effect of geometry variation on nucleation times and to address its role in the context of eukaryotic chemotaxis (i.e. the process which allows cells to identify and follow a gradient of chemical attractant). As a first step in this direction we study the nucleation dynamics of the 2d Ising model defined on a cylindrical l

C. E. Jimenez-Tejero, A. Ramos, I. Vidana

The interaction of the low lying pseudo-scalar mesons with the ground state baryons in the charm sector is studied within a coupled channel approach using a t-channel vector-exchange driving force. The amplitudes describing the scattering of the pseudo-scalar mesons off the ground-state baryons are obtained by solving the Lippmann--Schwinger equation. We ana

Sergio Doplicher

It was shown in the early Seventies that, in Local Quantum Theory (that is the most general formulation of Quantum Field Theory, if we leave out only the unknown scenario of Quantum Gravity) the notion of Statistics can be grounded solely on the local observable quantities (without assuming neither the commutation relations nor even the existence of unobserv

Daisuke Matsushita, De-Qi Zhang

For a compact hyperkähler manifold X, we show certain Zariski decomposition for every pseudo-effective R-divisor, and give a sufficient condition for X to be bimeromorphic to a (holomorphic) Lagrangian fibration. We also prove that any sequence of D-flops between projective hyperkähler manifolds terminates after finite steps.

Bharath K. Sriperumbudur, Arthur Gretton, Kenji Fukumizu, Bernhard Schölkopf

A Hilbert space embedding for probability measures has recently been proposed, with applications including dimensionality reduction, homogeneity testing, and independence testing. This embedding represents any probability measure as a mean element in a reproducing kernel Hilbert space (RKHS). A pseudometric on the space of probability measures can be defined

Bryan Webber

A simple method is proposed for determining the masses of new particles in collider events containing a pair of decay chains (not necessarily identical) of the form Z -> Y+1, Y -> X+2, X -> N+3, where 1,2 and 3 are visible but N is not. Initial study of a possible supersymmetric case suggests that the method can determine the four unknown masses in effective

C. Marquet, G. Beuf, B. -W. Xiao

Using the AdS/CFT correspondence, we compute the medium-induced energy loss of a decelerating heavy quark moving through a strongly-coupled supersymmetric Yang Mills plasma. In the regime where the deceleration is small, a perturbative calculation is possible and we obtain the first two corrections to the energy-loss rate of a heavy quark with constant veloc

Alex Shkotin

A program is usually represented as a word chain. It is exactly a word chain that appears as the lexical analyzer output and is parsed. The work shows that a program can be syntactically represented as an oriented word tree, that is a syntactic program tree, program words being located both in tree nodes and on tree arrows. The basic property of a tree is th

H1 Collaboration

A measurement of elastic deeply virtual Compton scattering gamma* p -> gamma p using e^+ p and e^- p collision data recorded with the H1 detector at HERA is presented. The analysed data sample corresponds to an integrated luminosity of 306 pb^-1, almost equally shared between both beam charges. The cross section is measured as a function of the virtuality Q^

Shahar Dobzinski

We study the power of polynomial-time truthful mechanisms comparing to polynomial time (non-truthful) algorithms. We show that there is a setting in which deterministic polynomial-time truthful mechanisms cannot guarantee a bounded approximation ratio, but a non-truthful FPTAS exists. We also show that in the same setting there is a universally truthful mech

Shane P. O&#39;Sullivan, Denise C. Gabuzda

We use observations of six &#34;blazars&#34; with the Very Long Baseline Array (VLBA), at eight frequencies (4.6, 5.1, 7.9, 8.9, 12.9, 15.4, 22.2, 43.1 GHz), to investigate the frequency-dependent position of their VLBI cores (&#34;core-shift&#34;) and their overall jet spectral distribution. By cross-correlating the optically thin jet emission, we are able

C. Berat, S. Bottai, D. De Marco, S. Moreggia

Future detection of Extensive Air Showers (EAS) produced by Ultra High Energy Cosmic Particles (UHECP) by means of space based fluorescence telescopes will open a new window on the universe and allow cosmic ray and neutrino astronomy at a level that is virtually impossible for ground based detectors. In this paper we summarize the results obtained in the con

Kazuhiro Sakai, Yuji Satoh

We systematically search for classical open string solutions in AdS_3 within the general class expressed by elliptic functions (i.e., the genus-one finite-gap solutions). By explicitly solving the reality and Virasoro conditions, we give a classification of the allowed solutions. When the elliptic modulus degenerates, we find a class of solutions with six nu

J. Ross, R. P. Thomas

We embed polarised orbifolds with cyclic stabiliser groups into weighted projective space via a weighted form of Kodaira embedding. Dividing by the (non-reductive) automorphisms of weighted projective space then formally gives a moduli space of orbifolds. We show how to express this as a reductive quotient and so a GIT problem, thus defining a notion of stab

S. Degla, L. Todjihounde

Let (M,g) be a Riemannian manifold and G a nondegenerate g-natural metric on its tangent bundle T M . In this paper we establish a relation between the Jacobi operators of (M,g) and that of (T M,G). In the case of a Riemannian surface (M,g), we compute explicitly the spectrum of some Jacobi operators of (TM,G) and give necessary and sufficient conditions for

Koji Harada, Hirofumi Kubo, Yuki Yamamoto

We show how the Apparently Noninvariant Terms (ANTs), which emerge in perturbation theory of nonlinear sigma models, are consistent with the nonlinearly realized symmetry by employing the Ward-Takahashi identity (in the form of an inhomogeneous Zinn-Justin equation). In the literature the discussions on ANTs are confined to the SU(2) case. We generalize them

L. P. Teo

In this article, we study the finite temperature Casimir effect for scalar field with Robin boundary conditions on two parallel plates in a background spacetime that has a compact internal manifold with arbitrary geometry. The finite temperature Casimir force acting on the plates is derived using the piston approach, with which we show that the divergences o

Yun Soo Myung

We explore a connection between generalized uncertainty principle (GUP) and modified Hořava-Lifshitz (HL) gravity. The GUP density function may be replaced by the cutoff function for the renormalization group of modified Hořava-Lifshitz gravity. We find the GUP-corrected graviton propagators and compare these with tensor propagators in the HL gravity. Two ar

G. Rocha, L. Pagano, K. M. Górski, K. M. Huffenberger

We introduce a new method to propagate uncertainties in the beam shapes used to measure the cosmic microwave background to cosmological parameters determined from those measurements. The method, which we call Markov Chain Beam Randomization, MCBR, randomly samples from a set of templates or functions that describe the beam uncertainties. The method is much f

Dmitry Kerner, Andras Nemethi

Consider the germ of an isolated surface singularity in $(\mC^3,0)$. The corresponding Milnor fibre possesses the homology lattice (the integral middle homology with a natural symmetric intersection form). An old question of A.Durfee (1978) asks: is the signature of this form non-increasing under degenerations? The present article answers negatively: We give

Noboru Ito

We construct a bicomplex for the categorification of the colored Jones polynomial. This work is motivated by the problem suggested by Anna Beliakova and Stephan Wehrli who discussed the categorification of the colored Jones polynomial in their paper.

Serguei Saavedra, Scott Powers, Trent McCotter, Mason A. Porter

We formulate the head-to-head matchups between Major League Baseball pitchers and batters from 1954 to 2008 as a bipartite network of mutually-antagonistic interactions. We consider both the full network and single-season networks, which exhibit interesting structural changes over time. We find interesting structure in the network and examine their sensitivi

Luxmi, P. J. Fisher, N. Srivastava, R. M. Feenstra

Graphene is formed on SiC(000-1) surfaces (the so-called C-face of the crystal) by annealing in vacuum, with the resulting films characterized by atomic force microscopy, Auger electron spectroscopy, scanning Auger microscopy and Raman spectroscopy. Morphology of these films is compared with the graphene films grown on SiC(0001) surfaces (the Si-face). Graph

Marco Tomamichel, Roger Colbeck, Renato Renner

In classical and quantum information theory, operational quantities such as the amount of randomness that can be extracted from a given source or the amount of space needed to store given data are normally characterized by one of two entropy measures, called smooth min-entropy and smooth max-entropy, respectively. While both entropies are equal to the von Ne

Gary Finnegan

The Geminga gamma ray source was first detected by the SAS-2 gamma-ray satellite observatory and the COS-B x-ray satellite observatory, and has been identified as a radio-quiet pulsar associated with a 300,000 year old supernova remnant. Geminga is one of the brightest GeV sources as seen by the Large Area Telescope on board the Fermi gamma-ray satellite obs

H. Abele, T. Jenke, H. Leeb, J. Schmiedmayer

We propose to apply Ramsey&#39;s method of separated oscillating fields to the spectroscopy of the quantum states in the gravity potential above a vertical mirror. This method allows a precise measurement of quantum mechanical phaseshifts of a Schrödinger wave packet bouncing off a hard surface in the gravitational field of the earth. Measurements with ultra

Motohisa Fukuda, Christopher King

Recently Hastings proved the existence of random unitary channels which violate the additivity conjecture. In this paper we use Hastings&#39; method to derive new bounds for the entanglement of random subspaces of bipartite systems. As an application we use these bounds to prove the existence of non-unital channels which violate additivity of minimal output

E. H. Brandt, G. P. Mikitik, E. Zeldov

As shown in recent experiments [Auslaender et al., Nature Physics 5, 35 (2009)] magnetic force microscopy permits one not only to image but also to manipulate an individual vortex in type-II superconductors, and this manipulation provides a new powerful tool to study vortex dynamics and pinning. We derive equations that describe the deformation of an individ

H S Guruprasad, H D Maheshappa

This paper proposes a dynamic bandwidth management algorithm in which more bandwidth is allocated for higher class users and also higher priority is given to the videos with higher popularity within a class using agent technology. The popularity and weight profile of the videos which is used for efficiently allocating bandwidth is periodically updated by a m

Jian Li, Amol Deshpande, Samir Khuller

We address the problem of efficiently gathering correlated data from a wired or a wireless sensor network, with the aim of designing algorithms with provable optimality guarantees, and understanding how close we can get to the known theoretical lower bounds. Our proposed approach is based on finding an optimal or a near-optimal {\em compression tree} for a g

B. Narasimhan, S. Santhosh baboo

In Heterogeneous mobile ad hoc networks (MANETs) congestion occurs with limited resources. Due to the shared wireless channel and dynamic topology, packet transmissions suffer from interference and fading. In heterogeneous ad hoc networks, throughput via a given route is depending on the minimum data rate of all its links. In a route of links with various da

Lucio Isa, Rut Besseling, Andrew B Schofield, Wilson C K Poon

We review recent advances in imaging the flow of concentrated suspensions, focussing on the use of confocal microscopy to obtain time-resolved information on the single-particle level in these systems. After motivating the need for quantitative (confocal) imaging in suspension rheology, we briefly describe the particles, sample environments, microscopy tools

Lars M. Johansen, Pier A. Mello

Weak values are usually associated with weak measurements of an observable on a pre- and post-selected ensemble. We show that more generally, weak values are proportional to the correlation between two pointers in a successive measurement. We show that this generalized concept of weak measurements displays a symmetry under reversal of measurement order. We s

G. E. Astrakharchik, J. Boronat, I. L. Kurbakov, Yu. E. Lozovik

The zero-temperature equation of state is analyzed in low-dimensional bosonic systems. In the dilute regime the equation of state is universal in terms of the gas parameter, i.e. it is the same for different potentials with the same value of the s-wave scattering length. Series expansions of the universal equation of state are reported for one- and two- dime

Ratnesh Kumar Jain, Dr. R. S. Kasana, Dr. Suresh Jain

World Wide Web is a huge data repository and is growing with the explosive rate of about 1 million pages a day. As the information available on World Wide Web is growing the usage of the web sites is also growing. Web log records each access of the web page and number of entries in the web logs is increasing rapidly. These web logs, when mined properly can p

Thiago Morais, Aldo Procacci

We exhibit a class of integer spin systems whose free energy can be written in term of an absolutely convergent series at any temperature. This class includes spin systems on $\Z^d$ interacting through infinite range pair potential polynomially decaying at large distances $r$ at a rate $1/r^{d+\e}$ with $\e>0$. It also contains the Blume-Emery-Griffiths mode

Muhammad Sohail, Abdur Rashid Khan

In this paper we present the process of Knowledge Elicitation through a structured questionnaire technique. This is an effort to depict a problem domain as Investigation of factors affecting taskforce productivity. The problem has to be solved using the expert system technology. This problem is the very first step how to acquire knowledge from the domain exp

M. Nardini, G. Ghisellini, G. Ghirlanda

The study of the rest frame properties of long Gamma-Ray bursts (GRBs) afterglows is a fundamental aspect for a better understanding of the nature of these powerful explosions. The launch of the Swift satellite (November 2004) marked a strong improvement of the observational capabilities of X-rays and optical afterglows. We studied the intrinsic optical afte

Vladimir V. Kassandrov

First principles should predetermine physical geometry and dynamics both together. In the &#34;algebrodynamics&#34; they follow solely from the properties of the biquaternion algebra $\B$ and the analysis over $\B$. We briefly present the algebrodynamics on the Minkowski background based on a nonlinear generalization to $\B$ of the Cauchi-Riemann analyticity

Oscar Cata, Vicent Mateu

In this letter we compute the leading chiral corrections to the ratio between the tensor and the vector decay couplings for the lowest lying vector meson multiplet (rho, K^*, phi). We show that the leading chiral logarithms arise from tadpole contributions and are therefore entirely fixed by chiral symmetry, while the next to leading corrections are purely a

S. Asztalos, S. Nikolaev, W. de Vries, S. Olivier

Cosmology with Type Ia supernovae heretofore has required extensive spectroscopic follow-up to establish a redshift. Though tolerable at the present discovery rate, the next generation of ground-based all-sky survey instruments will render this approach unsustainable. Photometry-based redshift determination is a viable alternative, but introduces non-negligi

T. Kotek, J. A. Makowsky

We consider functions of natural numbers which allow a combinatorial interpretation as density functions (speed) of classes of relational structures, s uch as Fibonacci numbers, Bell numbers, Catalan numbers and the like. Many of these functions satisfy a linear recurrence relation over $\mathbb Z$ or ${\mathbb Z}_m$ and allow an interpretation as counting t

Sukosin Thongrattanasiri, Justin Elser, Viktor A. Podolskiy

We analyze wave propagation in coupled planar waveguides, pointing specific attention to modal cross-talk and out-of-plane scattering in quasi-planar photonics. An algorithm capable of accurate numerical computation of wave coupling in arrays of planar structures is developed and illustrated on several examples of plasmonic and volumetric waveguides. An anal

Hailiang Wang, Joshua Tucker Robinson, Xiaolin Li, Hongjie Dai

Graphene has attracted much attention due to its interesting properties and potential applications. Chemical exfoliation methods have been developed to make graphene recently, aimed at large-scale assembly and applications such as composites and Li ion batteries. Although efficient, the chemical exfoliation methods involve oxidation of graphene and introduce

Philip Kaaret, Hua Feng

X-ray monitoring observations were performed with the Swift observatory of the ultraluminous X-ray sources Holmberg IX X-1, NGC 5408 X-1, and NGC 4395 X-2 and also of the nuclear X-ray source in NGC 4395. Holmberg IX X-1 remains in the hard X-ray spectral state as its flux varies by a factor of 7 up to an (isotropic) luminosity of 2.8E40 erg/s. This behavior

R. Decarli, M. Dotti, R. Falomo, A. Treves

We present an imaging study of the black hole binary candidate SDSS J1536+0441 (z=0.3893), based on deep, high resolution VzK images collected at the ESO/VLT. The images clearly show an asymmetric elongation, indicating the presence of a companion source at ~1&#34; (~5 kpc projected distance) East from the quasar. The host galaxy of the quasar is marginally

J. C. Yee, A. Udalski, T. Sumi, Subo Dong

We analyze the extreme high-magnification microlensing event OGLE-2008-BLG-279, which peaked at a maximum magnification of A ~ 1600 on 30 May 2008. The peak of this event exhibits both finite-source effects and terrestrial parallax, from which we determine the mass of the lens, M_l=0.64 +/- 0.10 M_Sun, and its distance, D_l = 4.0 +/- 0.6. We rule out Jupiter

Johannes Huebschmann

Let G be a Lie goup, let M and N be smooth connected G-manifolds, let f be a smooth G-map from M to N, and let P denote the fiber of f. Given a closed and equivariantly closed relative 2-form for f with integral periods, we construct the principal G-circle bundles with connection on P having the given relative 2-form as curvature. Given a compact Lie group K

Alak Ray

Nuclear reactions transform atomic nuclei inside stars. This is the process of stellar nucleosynthesis. The basic concepts of determining nuclear reaction rates inside stars are reviewed. How stars manage to burn their fuel so slowly most of the time are also considered. Stellar thermonuclear reactions involving protons in hydrostatic burning are discussed f

Scott Baldridge, Ben McCarty

In this short note we highlight some of the differences between cube diagrams and grid diagrams. We also list examples of small cube diagrams for all knots up to 7 crossings and give some examples of links.

Marius Mantoiu, Radu Purice

We extend the Bargmann transform to the magnetic pseudodifferential calculus, using gauge-covariant families of coherent states. We also introduce modulation mappings, a first step towards adapting modulation spaces to the magnetic case.

Helena Mihaljevic-Brandt

Let f be a transcendental entire map that is subhyperbolic, i.e., the intersection of the Fatou set F(f) and the postsingular set P(f) is compact and the intersection of the Julia set J(f) and P(f) is finite. Assume that no asymptotic value of f belongs to J(f) and that the local degree of f at all points in J(f) is bounded by some finite constant. We prove

J. P. Eisenstein, L. N. Pfeiffer, K. W. West

Tunneling measurements on 2D electron gases at high magnetic field reveal a qualitative difference between the two spin sublevels of the lowest Landau level. While the tunneling current-voltage characteristic at filling factor $ν= 1/2$ is a single peak shifted from zero bias by a Coulomb pseudogap, the spectrum at $ν=3/2$ shows a well-resolved double peak st

Xiang He, Aylin Yener

Recent results have shown that structured codes can be used to construct good channel codes, source codes and physical layer network codes for Gaussian channels. For Gaussian channels with secrecy constraints, however, efforts to date rely on random codes. In this work, we advocate that structured codes are useful for providing secrecy, and show how to compu