July 2009 arXiv papers — page 44

T. Wang, Y. Qiu, H. Cai, J. Deng

The Space multi-band Variable Object Monitor (SVOM) is a proposed Chinese astronomical satellite, dedicated to the detection, localization and measurement of the gamma-ray bursts (GRBs) on the cosmological scale. An efficient algorithm is developed for the purpose of onboard star extraction from the CCD images obtained with the Visible Telescope (VT) on boar

Yoichi Takeda, Dong-Il Kang, Inwoo Han, Byeong-Cheol Lee

An extensive non-LTE abundance analysis based on Na I 5890/5896 doublet lines was carried out for a large unbiased sample of ~120 A-type main-sequence stars (including 23 Hyades stars) covering a wide v_e sin i range of ~10--300 km/s, with an aim to examine whether the Na abundances in such A dwarfs can be reliably established from these strong Na I D lines.

W. Zheng, J. Deng

A two-component jet model is proposed to explain the unusual afterglow of GRB 070419A. Regarding the optical light curve, a wide "jet" with an opening angle of > 30-40 degrees is assumed to produce the late shallow decay, while the three early power-law segments must be caused by a narrow jet with an opening angle of about 2-4 degrees. Additional ene

Dinh-V-Trung

In this paper we investigate the polarization property of the radiation amplified by astronomical masers in the presence of a strong magnetic field. Our model explicitly takes into account the broadband nature of the radiation field and the interaction of the radiation with the maser transition J=1--0. The amplification of different realisations of the backg

Dinh-V-Trung

In this paper we re-analyse the amplification process of broadband continuum radiation by astronomical masers in one-dimensional case. The basic equations appropriate for the scalar maser and the random nature of the maser radiation field are derived from basic physical principles. Comparision with the standard radiation transfer equation allows us to examin

M. C. B. Abdalla, J. M. Hoff da Silva, R. da Rocha

Motivated by possible extensions of the braneworld models with two branes, we investigate some consequences of a variable brane tension using the well established results on consistency conditions. By a slight modification of the usual stress-tensor used in order to derive the braneworld sum rules, we find out some important constraints obeyed by time depend

Ralf Lehnert

In recent years, the breakdown of spacetime symmetries has been identified as a promising research field in the context of Planck-scale phenomenology. For example, various theoretical approaches to the quantum-gravity problem are known to accommodate minute violations of CPT invariance. This talk covers various topics within this research area. In particular

Bernhard Hermann Haak, Birgit Jacob

Volterra observations systems with scalar kernels are studied. New sufficient conditions for admissibility of observation operators are developed. The obtained results are applied to time-fractional diffusion equations of distributed order.

Nathalie Eisenbaum, Mohammud Foondun, Davar Khoshnevisan

Consider the stochastic heat equation $\partial_t u = \sL u + \dot{W}$, where $\sL$ is the generator of a [Borel right] Markov process in duality. We show that the solution is locally mutually absolutely continuous with respect to a smooth perturbation of the Gaussian process that is associated, via Dynkin's isomorphism theorem, to the local times of the

Leonid P. Pryadko, Gregory Quiroz

We consider the effect of broadband decoherence on the performance of refocusing sequences, having in mind applications of dynamical decoupling in concatenation with quantum error correcting codes as the first stage of coherence protection. Specifically, we construct cumulant expansions of effective decoherence operators for a qubit driven by a pulse of a ge

S. Gomez, A. Arenas, J. Borge-Holthoefer, S. Meloni

Many epidemic processes in networks spread by stochastic contacts among their connected vertices. There are two limiting cases widely analyzed in the physics literature, the so-called contact process (CP) where the contagion is expanded at a certain rate from an infected vertex to one neighbor at a time, and the reactive process (RP) in which an infected ind

Dennis Bessada, William H. Kinney, Konstantinos Tzirakis

We study DBI inflation based upon a general model characterized by a power-law flow parameter $ε(ϕ)\proptoϕ^α$ and speed of sound $c_s(ϕ)\proptoϕ^β$, where $α$ and $β$ are constants. We show that in the slow-roll limit this general model gives rise to distinct inflationary classes according to the relation between $α$ and $β$ and to the time evolution of the

P. N. Kopnin

We study the low-energy theorems of QCD from the point of view of the dual AdS/QCD models and demonstrate that these models are compatible with the theorems in the chiral limit, i.e. the arising expressions have the same analytical behavior at the pole when the quark mass tends to zero. Low-energy theorems are formulated in terms of the spectral density of t

A. Gonzalez-Tudela, E. del Valle, E. Cancellieri, C. Tejedor

We study the effect of pure dephasing on the strong-coupling between a quantum dot and the single mode of a microcavity in the nonlinear regime. We show that the photoluminescence spectrum of the system has a robust tendency to display triplet structures, instead of the expected Jaynes-Cummings pairs of doublets at the incommensurate frequencies $\pm(\sqrt{n

S. R. Dicker, B. S. Mason, P. M. Korngut, W. D. Cotton

We have used the new 90GHz MUSTANG camera on the Robert C. Byrd Green Bank Telescope (GBT) to map the bright Huygens region of the star-forming region M42 with a resolution of 9" and a sensitivity of 2.8mJy/beam. 90GHz is an interesting transition frequency, as MUSTANG detects both the free-free emission characteristic of the HII region created by the Tr

Matthias Köppe, Maurice Queyranne, Christopher Thomas Ryan

We consider discrete bilevel optimization problems where the follower solves an integer program with a fixed number of variables. Using recent results in parametric integer programming, we present polynomial time algorithms for pure and mixed integer bilevel problems. For the mixed integer case where the leader's variables are continuous, our algorithm a

Sergey Bravyi, Cristopher Moore, Alexander Russell

Quantum k-SAT is the problem of deciding whether there is a n-qubit state which is perpendicular to a set of vectors, each of which lies in the Hilbert space of k qubits. Equivalently, the problem is to decide whether a particular type of local Hamiltonian has a ground state with zero energy. We consider random quantum k-SAT formulas with n variables and m =

Evan Frodermann, Ulrich Heinz

Currently, the only known way to obtain experimental information about the space-time structure of a heavy-ion collision is through 2-particle momentum correlations. Azimuthally sensitive HBT interferometry (Hanbury Brown-Twiss intensity interferometry) can complement elliptic flow measurements by constraining the spatial deformation of the source and its ti

Michael Jablonski, Andrea Young

The purpose of this paper is to introduce the Ricci Yang-Mills soliton equations on nilpotent Lie groups. In the 2-step nilpotent setting, we show that these equations are strictly weaker than the Ricci soliton equations. Using techniques from Geometric Invariant Theory, we develop a procedure to build many different kinds of Ricci Yang-Mills solitons. We fi

J. K. Freericks, V. Turkowski

Spectral moment sum rules are presented for the inhomogeneous many-body problem described by the fermionic Falicov-Kimball or Hubbard models. These local sum rules allow for arbitrary hoppings, site energies, and interactions. They can be employed to quantify the accuracy of numerical solutions to the inhomogeneous many-body problem like strongly correlated

Jonas de Woul, Edwin Langmann

We compute mean field phase diagrams of two closely related interacting fermion models in two spatial dimensions (2D). The first is the so-called 2D t-t'-V model describing spinless fermions on a square lattice with local hopping and density-density interactions. The second is the so-called 2D Luttinger model that provides an effective description of the

Muriel Livernet, Birgit Richter

We prove that E_n-homology of non-unital commutative algebras can be described as functor homology when one considers functors from a certain category of planar trees with n levels. For different n these homology theories are connected by natural maps, ranging from Hochschild homology and its higher order versions to Gamma homology.

Minoru Eto, Muneto Nitta

QCD is expected to be in the color-flavor locking phase in high baryon density, which exhibits color superconductivity. The most fundamental topological objects in the color superconductor are non-Abelian vortices which are topologically stable color magnetic flux tubes. We present numerical solutions of the color magnetic flux tube for diverse choices of th

M. A. Tanatar, J. P. Reid, H. Shakeripour, X. G. Luo

The temperature and magnetic field dependence of the in-plane thermal conductivity $κ$ of the iron-arsenide superconductor Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ was measured down to $T \simeq 50$ mK and up to $H = 15$ T as a function of Co concentration $x$ in the range 0.048 $ \leq x \leq $ 0.114. In zero magnetic field, a negligible residual linear term in $κ/T$

Aliaa Barakat, Alberto De Sole, Victor G. Kac

We lay down the foundations of the theory of Poisson vertex algebras aimed at its applications to integrability of Hamiltonian partial differential equations. Such an equation is called integrable if it can be included in an infinite hierarchy of compatible Hamiltonian equations, which admit an infinite sequence of linearly independent integrals of motion in

Sergey E. Koposov, Hans-Walter Rix, David W. Hogg

The narrow GD-1 stream of stars, spanning 60 deg on the sky at a distance of ~10 kpc from the Sun and ~15 kpc from the Galactic center, is presumed to be debris from a tidally disrupted star cluster that traces out a test-particle orbit in the Milky Way halo. We combine SDSS photometry, USNO-B astrometry, and SDSS and Calar Alto spectroscopy to construct a c

Matthias Beck, Benjamin Braun

Proper vertex colorings of a graph are related to its boundary map, also called its signed vertex-edge incidence matrix. The vertex Laplacian of a graph, a natural extension of the boundary map, leads us to introduce nowhere-harmonic colorings and analogues of the chromatic polynomial and Stanley's theorem relating negative evaluations of the chromatic p

CDF Collaboration

We report the recent charged Higgs search in top quark decays in 2.2/fb CDF data. This is the first attempt to search for charged Higgs using fully reconstructed mass assuming H->c-sbar in small tan beta region. No evidence of a charged Higgs is observed in the CDF data, hence 95% upper limits are placed at B(t->H+b) < 0.1-0.3. The upper limits can be used t

Evgeny Gorbovskoy, Kirill Ivanov, Vladimir Lipunov, Victor Kornilov

At present time Robotic observatory making is of current importance. Having a large field of view and being able to point at anywhere, Robotic astronomical systems are indispensable when they looking for transients like grb, supernovae explosions, novae etc, as it&#39;s impossible in these cases to foresee what you should point you telescope at and when. In

F. Colomo, A. G. Pronko

The problem of the form of the `arctic&#39; curve of the six-vertex model with domain wall boundary conditions in its disordered regime is addressed. It is well-known that in the scaling limit the model exhibits phase-separation, with regions of order and disorder sharply separated by a smooth curve, called the arctic curve. To find this curve, we study a mu

F. Bazzocchi, D. G. Cerdeno, C. Munoz, J. W. F. Valle

We provide a scenario where naturally small and calculable neutrino masses arise from a supersymmetry breaking renormalization-group-induced vacuum expectation value. We adopt a minimal supergravity scenario without ad hoc supersymmetric mass parameters. The lightest supersymmetric particle can be an isosinglet scalar neutrino state, potentially viable as WI

Christopher T. Hill

The Dirac quantization procedure of a magnetic monopole can be used to derive the coefficient of the D=3 Chern-Simons term through a self-consistency argument, which can be readily generalized to any odd D. This yields consistent and covariant axial anomaly coefficients on a D-1 boundary, and Chern-Simons term coefficients in D. In D=3 magnetic monopoles can

M. J. Calderon, B. Valenzuela, E. Bascones

We propose a five-band tight-binding model for the Fe-As layers of iron pnictides with the hopping amplitudes calculated within the Slater-Koster framework. The band structure found in DFT, including the orbital content of the bands, is well reproduced using only four fitting parameters to determine all the hopping amplitudes. The model allows to study the c

S. M. Perlaza, N. Fawaz, S. Lasaulce, M. Debbah

We describe a non-cooperative interference alignment (IA) technique which allows an opportunistic multiple input multiple output (MIMO) link (secondary) to harmlessly coexist with another MIMO link (primary) in the same frequency band. Assuming perfect channel knowledge at the primary receiver and transmitter, capacity is achieved by transmiting along the sp

Jean-Marie Cornuet, Jean-Michel Marin, Antonietta Mira, Christian P. Robert

The Adaptive Multiple Importance Sampling (AMIS) algorithm is aimed at an optimal recycling of past simulations in an iterated importance sampling scheme. The difference with earlier adaptive importance sampling implementations like Population Monte Carlo is that the importance weights of all simulated values, past as well as present, are recomputed at each

B. Obermayer, E. Frey

The dynamic response of prestressed semiflexible biopolymers is characterized by the propagation and relaxation of tension, which arises due to the near inextensibility of a stiff backbone. It is coupled to the dynamics of contour length stored in thermal undulations, but also to the local relaxation of elongational strain. We present a systematic theory of

U. Sperhake, V. Cardoso, F. Pretorius, E. Berti

We study the collision of two highly boosted equal mass, nonrotating black holes with generic impact parameter. We find such systems to exhibit zoom-whirl behavior when fine tuning the impact parameter. Near the threshold of immediate merger the remnant black hole Kerr parameter can be near maximal (a/M about 0.95) and the radiated energy can be as large as

E. Akofor

We present a way of understanding the curvature of space-time, the basic philosophy being that the (linear) geometry of any space is determined by the (linear) functionals on the algebra(s) of any fields defined on the space. It is known that quantum states or hypothetical measurements on a quantum system may be regarded as unit or normalized positive (or no

Fernando Charro, Jesus Garcia Azorero, Julio D. Rossi

In this paper we show how to use a Tug-of-War game to obtain existence of a viscosity solution to the infinity laplacian with non-homogeneous mixed boundary conditions. For a Lipschitz and positive function $g$ there exists a viscosity solution of the mixed boundary value problem, $$ \{\begin{array}{ll} \displaystyle -Δ_{\infty}u(x)=0\quad & \text{in} Ω, \di

Michael Sentef, Jan Kunes, Philipp Werner, Arno P. Kampf

We study a model of a covalent band insulator with on-site Coulomb repulsion at half-filling using dynamical mean-field theory. Upon increasing the interaction strength the system undergoes a discontinuous transition from a correlated band insulator to a Mott insulator with hysteretic behavior at low temperatures. Increasing the temperature in the band insul

Leandro G. Almeida, George Sterman, Werner Vogelsang

We study the resummation of large logarithmic perturbative corrections to the partonic cross sections relevant for di-hadron production in hadronic collisions, H1 H2 -> h1 h2 X, at high invariant mass of the produced hadron pair. These corrections arise near the threshold for the partonic reaction and are associated with soft-gluon emission. We perform the r

Mircea Cimpoeas

We compute the Stanley depth for the quotient ring of a square free Veronese ideal and we give some bounds for the Stanley depth of a square free Veronese ideal. In particular, it follows that both satisfy the Stanley's conjecture.

Jian-Guo Liu, Tao Zhou, Qiang Guo, Bing-Hong Wang

In this paper, based on a weighted projection of the user-object bipartite network, we study the effects of user tastes on the mass-diffusion-based personalized recommendation algorithm, where a user&#39;s tastes or interests are defined by the average degree of the objects he has collected. We argue that the initial recommendation power located on the objec

Stefan Ankirchner, Christophette Blanchet-Scalliet, Anne Eyraud-Loisel

This paper is concerned with the determination of credit risk premia of defaultable contingent claims by means of indifference valuation principles. Assuming exponential utility preferences we derive representations of indifference premia of credit risk in terms of solutions of Backward Stochastic Differential Equations (BSDE). The class of BSDEs needed for

Joyee Ghosh, R. Ghosh, Deepak Kumar

A three-level atom in a $Λ$ configuration trapped in an optical cavity forms a basic unit in a number of proposed protocols for quantum information processing. Through control with an appropriate laser, this system allows for efficient storage of cavity photons into long-lived atomic excitations, and their retrieval with high fidelity. This process presumes

Anthony J. Baltz, Yuri Gorbunov, Spencer R. Klein, Joakim Nystrand

Highly charged relativistic heavy ions have high cross-sections for two-photon interactions. The photon flux is high enough that two-photon interactions may be accompanied by additional photonuclear interactions. Except for the shared impact parameter, these interactions are independent. Additional interactions like mutual Coulomb excitation are of experimen

Juan Cortina, Florian Goebel, Thomas Schweizer

The MAGIC-I telescope is the largest single-dish Imaging Atmospheric Cherenkov telescope in the world. A second telescope, MAGIC-II, will operate in coincidence with MAGIC-I in stereoscopic mode. MAGIC-II is a clone of MAGIC-I, but with a number of significant improvements, namely a highly pixelized camera with a wider trigger area, improved optical analog s

Zheng-Cheng Gu, Xiao-Gang Wen

The general equivalence principle and the associated diffeomorphism gauge symmetry are regarded as a founding principles of nature. But, one may wonder, can diffeomorphism gauge symmetry emerge as a low energy property of certain topological/quantum order in a qbit model that has no diffeomorphism gauge symmetry? In this paper, we showed that, at least, the

Robert Beig, Gary W. Gibbons, Richard M. Schoen

Generalizing previous work by two of us, we prove the non-existence of certain stationary configurations in General Relativity having a spatial reflection symmetry across a non-compact surface disjoint from the matter region. Our results cover cases such that of two symmetrically arranged rotating bodies with anti-aligned spins in $n+1$ ($n \geq 3$) dimensio

Yuko Urakawa, Tsutomu Kobayashi

We explore the possibility that the dark matter and dark energy are mimicked by a single fluid or by a single $k$-essence-like scalar field. The so called Chaplygin gas unified dark matter models can reproduce the observed matter power spectrum by adding a baryon component. It has been argued that the evolution of the baryon fluctuations is particularly favo

Samuel L. Braunstein, Stefano Pirandola, Karol Życzkowski

We show that, in order to preserve the equivalence principle until late times in unitarily evaporating black holes, the thermodynamic entropy of a black hole must be primarily entropy of entanglement across the event horizon. For such black holes, we show that the information entering a black hole becomes encoded in correlations within a tripartite quantum s

Aharon Davidson, Shimon Rubin

A gravitational extension of Dirac&#39;s &#34;Extensible model of the electron&#34; is presented. The Dirac bubble, treated as a 3-dim electrically charged brane, is dynamically embedded within a 4-dim $Z_{2}$-symmetric Reissner-Nordstrom bulk. Crucial to our analysis is the gravitational extension of Dirac&#39;s brane variation prescription; its major effec

G. Gallavotti, E. Presutti

Thermostats models in space dimension d=1,2,3 for nonequilibrium statistical mechanics are considered and it is shown that, in the thermodynamic limit, the evolutions admit infinitely many constants of motion: namely the intensive observables.

Jacopo Gandini

Let G be a simply connected semisimple algebraic group over an algebraically closed field k of characteristic 0 and let V be a rational simple G-module of finite dimension. If G/H \subset P(V) is a spherical orbit and if X is its closure, then we describe the orbits of X and those of its normalization. If moreover the wonderful completion of G/H is strict, t

Edward D. Kim, Francisco Santos

The Hirsch conjecture was posed in 1957 in a letter from Warren M. Hirsch to George Dantzig. It states that the graph of a d-dimensional polytope with n facets cannot have diameter greater than n - d. Despite being one of the most fundamental, basic and old problems in polytope theory, what we know is quite scarce. Most notably, no polynomial upper bound is

Marta Tyran-Kaminska

For a strictly stationary sequence of random vectors in $\mathbb{R}^d$ we study convergence of partial sum processes to Lévy stable process in the Skorohod space with $J_1$-topology. We identify necessary and sufficient conditions for such convergence and provide sufficient conditions when the stationary sequence is strongly mixing.

M. Breitschaft, V. Tinkl, N. Pavlenko, S. Thiel

Using tunneling spectroscopy we have measured the spectral density of states of the mobile, two-dimensional electron system generated at the LaAlO3-SrTiO3 interface. As shown by the density of states the interface electron system differs qualitatively, first, from the electron systems of the materials defining the interface and, second, from the two-dimensio

W. Zhao, D. Baskaran, L. P. Grishchuk

The relic gravitational waves (gw) are the cleanest probe of the violent times in the very early history of the Universe. They are expected to leave signatures in the observed cosmic microwave background anisotropies. We significantly improved our previous analysis [1] of the 5-year WMAP $TT$ and $TE$ data at lower multipoles $\ell$. This more general analys

Alberto C. Balfagon, Raul Ramirez-Satorras

In this paper we study a model of cosmic evolution, assuming that the different components of the universe could interact between them any time. An effective equation of state (EOS) for the universe has been used as well. A particular function for w, which gives a good agreement between our results and the experimental data, has been studied. Finally, the mo

Kazuo Ghoroku, Akihiro Nakamura, Fumihiko Toyoda

We study the stability of a special form of D brane embedding which is regarded as a bound state of D$_n$ and anti-D$_n$-brane embedded in a 10D supergravity background which is dual to a confining gauge theory. For D5 branes with $U(1)$ flux, their bound state configuration can be regarded as the baryonium vertex. For D branes of $n=6$ and 8 without the $U(

R. De los Reyes, W. Bednarek, M. Camara, M. Lopez

During the last 4 years the MAGIC collaboration has searched for high-energy gamma-ray emission of some of the most promising pulsar candidates. The low energy threshold of MAGIC offered the opportunity for a high sensitivity search just above 50-100 GeV (since 2008 a new trigger system has decreased the energy threshold to 25 GeV), an energy region up to no

Isaac Vidana, Constanca Providencia, Artur Polls, Arnau Rios

We perform a systematic analysis of the density dependence of the nuclear symmetry energy within the microscopic Brueckner--Hartree--Fock (BHF) approach using the realistic Argonne V18 nucleon-nucleon potential plus a phenomenological three body force of Urbana type. Our results are compared thoroughly to those arising from several Skyrme and relativistic ef

Matthias J. Weber, Hans-Peter Schröcker

We give a variety of uniqueness results for minimal ellipsoids circumscribing and maximal ellipsoids inscribed into a convex body. Uniqueness follows from a convexity or concavity criterion on the function used to measure the size of the ellipsoid. Simple examples with non-unique minimal or maximal ellipsoids conclude this article.

V. V. Fedorov, M. Jentschel, I. A. Kuznetsov, E. G. Lapin

An experiment using a prototype setup to search for the neutron electric dipole moment by measuring spin-rotation in a non-centrosymmetric crystal (quartz) was carried out to investigate statistical sensitivity and systematic effects of the method. It has been demonstrated that the concept of the method works. The preliminary result of the experiment is $d_{

Oana Alexandru

It is the purpose of the present paper to outline an introduction in theory of embeddings in the manifold Osc^{2}M. First, we recall the notion of 2-osculator bundle. The second section is dedicated to the notion of submanifold in the total space of the 2-osculator bundle, the manifold Osc^{2}M. A moving frame is constructed. The induced N-linear connections

Ramakrishnan Iyer, Ayan Mukhopadhyay

The AdS/CFT correspondence defines a sector with universal strongly coupled dynamics in the field theory as the dual of pure gravity in AdS described by Einstein&#39;s equation with a negative cosmological constant. We explain here, from the field-theoretic viewpoint how the dynamics in this sector gets determined by the expectation value of the energy-momen

Miguel Alcubierre, Juan Carlos Degollado, Marcelo Salgado

We consider the Einstein-Maxwell system as a Cauchy initial value problem taking the electric and magnetic fields as independent variables. Maxwell&#39;s equations in curved spacetimes are derived in detail using a 3+1 formalism and their hyperbolic properties are analyzed, showing that the resulting system is symmetric hyperbolic. We also focus on the probl

Vincent Ricardo Daria, Christian Stricker, Richard Bowman, Stephen Redman

We demonstrate dynamic and arbitrary multisite two-photon excitation in three dimensions using the holographic projection method. Rapid response (fourth dimension) is achieved through high-speed noniterative calculation of the hologram using a video graphics accelerator board. We verify that the projected asymmetric spot configurations have sufficient spatio

A. A. Saharian, T. A. Vardanyan

Wightman function, the vacuum expectation values of the field squared and the energy-momentum tensor are investigated for a scalar field with general curvature coupling parameter in the geometry of a plate in the de Sitter spacetime. Robin boundary condition for the field operator is assumed on the plate. The vacuum expectation values are presented as the su

Orestis Faklaris, Vandana Joshi, Theano Irinopoulou, Patrick Tauc

Diamond nanoparticles (nanodiamonds) have been recently proposed as new labels for cellular imaging. For small nanodiamonds (size <40 nm) resonant laser scattering and Raman scattering cross-sections are too small to allow single nanoparticle observation. Nanodiamonds can however be rendered photoluminescent with a perfect photostability at room temperature.

Hosho Katsura, Masahiro Sato, Takashi Furuta, Naoto Nagaosa

The low-energy dynamical optical response of dimerized and undimerized spin liquid states in a one-dimensional charge transfer Mott insulator is theoretically studied. An exact analysis is given for the low-energy asymptotic behavior using conformal field theory for the undimerized state. In the dimerized state, the infrared absorption due to the bound state

Hongbin Sun, Shicheng Wang

This note will become part of a new paper with more authors.

H. F. Chau, K. H. Ho

Many entanglement distillation schemes use either universal random hashing or breeding as their final step to obtain almost perfect shared EPR pairs. In spite of a high yield, the hardness of decoding a random linear code makes the use of random hashing and breeding infeasible in practice. In this pilot study, we analyze the performance of the recurrence met

Dilian Yang

In this paper, we initiate the study of endomorphisms and modular theory of the graph C*-algebras $Ø_θ$of a 2-graph $\Fth$ on a single vertex. We prove that there is a semigroup isomorphism between unital endomorphisms of $Ø_θ$ and its unitary pairs with a \textit{twisted property}. We characterize when endomorphisms preserve the fixed point algebra $\fF$ of

Shuhei Mano

Gene conversion is a mechanism by which a double-strand break in a DNA molecule is repaired using a homologous DNA molecule as a template. As a result, one gene is &#39;copied and pasted&#39; onto the other gene. It was recently reported that the direction of gene conversion appears to be biased towards G and C nucleotides. In this paper a stochastic model o

E. G. Delgado-Acosta, M. Napsuciale

We calculate Compton scattering off an elementary spin 3/2 particle in a recently proposed framework for the description of elementary high spin fields based on the projection onto eigen-subspaces of the Casimir operators of the Poincare group. We also calculate this process in the conventional Rarita-Schwinger formalism. Both formalisms yield the correct Th

Hai-Tao Zhang, Ning Wang, Michael Z. Q. Chen, Tao Zhou

Among natural biological flocks/swarms or even mass social activities, when the collective behaviors of the followers has been dominated by the moving direction or opinion of one leader group, it seems very difficult for later-coming leaders to reverse the orientation of the mass followers, especially when they are in quantitative minority. This Letter repor

Jason Asher

We consider von Neumann algebras generated by the stationary laws of free stochastic differential equations of the form $dX_t = dS_t -1/2 DV(X_t)$ for a suitably convex multivariate noncommutative polynomial $V$. Using techniques of Guionnet and Shlyakhtenko, we prove that these von Neumann algebras have property AO of Ozawa and are thus solid.

M. M. Selim, S. Abe, K. Harigaya

An analytical method to investigate wave propagation in single- and double- walled carbon nanotubes under initial compression stress is presented. The nanotube structures are treated within the multilayer thin shell approximation with the elastic properties taken to be those of the graphene sheet. The governing equations are derived based on Flugge equations

A. I. Nesterov, S. G. Ovchinnikov

The relationship is established between the Berry phase and spin crossover in condensed matter physics induced by high pressure. It is shown that the geometric phase has topological origin and can be considered as the order parameter for such transition.

C. R. Rotundu, D. T. Keane, B. Freelon, S. D. Wilson

The electronic phase diagram of PrFeAsO$_{1-x}$F$_{x}$ (0$\leq$x$\leq$0.225) has been determined using synchrotron X-ray powder diffraction, magnetization and resistivity measurements. The structural transition temperature is suppressed from 154 K to $\approx$120 K and the magnetic phase transitions of both iron and praseodymium ions are completely suppresse

Scott M. Summers

This paper concerns the self-assembly of scaled-up versions of arbitrary finite shapes. We work in the multiple temperature model that was introduced by Aggarwal, Cheng, Goldwasser, Kao, and Schweller (Complexities for Generalized Models of Self-Assembly, SODA 2004). The multiple temperature model is a natural generalization of Winfree&#39;s abstract tile as

S. R. Dicker, P. M. Korngut, B. S. Mason, P. A. R. Ade

MUSTANG is a 90 GHz bolometer camera built for use as a facility instrument on the 100 m Robert C. Byrd Green Bank radio telescope (GBT). MUSTANG has an 8 by 8 focal plane array of transition edge sensor bolometers read out using time-domain multiplexed SQUID electronics. As a continuum instrument on a large single dish MUSTANG has a combination of high reso

P. W. Hodge, O. K. Krienke, M. Bellazzini, S. Perina

We report on the properties of 89 low mass star clusters located in the vicinity of luminous young clusters (blue globulars) in the disk of M31. 82 of the clusters are newly detected. We have determined their integrated magnitudes and colors, based on a series of Hubble Space Telescope Wide Field/Planetary Camera 2 exposures in blue and red (HST filters F450

Robert Jacobson

An open set in C^n is pseudoconvex if and only if its intersection with every affine subspace of complex dimension two as seen as an open set in C^2 is pseudoconvex.

G. F. Bertsch, C. W. Johnson

We carry out an interacting shell-model study of binding energies and spectra in the $sd$-shell nuclei to examine the effect of truncation of the shell-model spaces. Starting with a Hamiltonian defined in a larger space and truncating to the $sd$ shell, the binding energies are strongly affected by the truncation, but the effect on the excitation energies is

Michael Attard, Martin Houde, Giles Novak, Hua-bai Li

We present single-dish 350 micron dust continuum polarimetry as well as HCN and HCO+ J=4-3 rotational emission spectra obtained on NGC 1333 IRAS 4. The polarimetry indicates a uniform field morphology over a 20&#34; radius from the peak continuum flux of IRAS 4A, in agreement with models of magnetically supported cloud collapse. The field morphology around I

Yuri A. Freiman, B. Hetenyi, S. M. Tretyak

An overview of results of models of coupled quantum rotors is presented. We focus on rotors with dipolar and quadrupolar potentials in two and three dimensions, potentials which correspond to approximate descriptions of real molecules adsorbed on surfaces and in the solid phase. Particular emphasis is placed on the anomalous reentrant phase transition which

J. -P. Ismer, Ilya Eremin, Enrico Rossi, Dirk K. Morr

We study the emergence of multiband superconductivity with $s$- and $d-$wave symmetry on the background of spin density wave (SDW). We show that the SDW coherence factors renormalize the momentum dependence of the superconducting (SC) gap, yielding a SC state with an \emph{unconventional} s-wave symmetry. Interband Cooper pair scattering stabilizes supercond

Ankur Gupta, Anna Kispert, Jonathan P. Sorenson

In this paper, we present a framework based on a simple data structure and parameterized algorithms for the problems of finding items in an unsorted list of linearly ordered items based on their rank (selection) or value (search). As a side-effect of answering these online selection and search queries, we progressively sort the list. Our algorithms are based

Arend Hintze, Christoph Adami

Networks describing the interaction of the elements that constitute a complex system grow and develop via a number of different mechanisms, such as the addition and deletion of nodes, the addition and deletion of edges, as well as the duplication or fusion of nodes. While each of these mechanisms can have a different cause depending on whether the network is

Marta Lewicka

We prove that the critical points of the 3d nonlinear elasticity functional on shells of small thickness $h$ and around the mid-surface $S$ of arbitrary geometry, converge as $h\to 0$ to the critical points of the von Kármán functional on $S$, recently derived in \cite{lemopa1}. This result extends the statement in \cite{MuPa}, derived for the case of plates

P. Romano, L. Sidoli, G. Cusumano, V. La Parola

Swift has allowed the possibility to give Supergiant Fast X-ray Transients (SFXTs), the new class of High Mass X-ray Binaries discovered by INTEGRAL, non serendipitous attention throughout all phases of their life. We present our results based on the first year of intense Swift monitoring of four SFXTs, IGR J16479-4514, XTE J1739-302, IGR J17544-2619 and AX

Marcelo A. Kuroda, Jean Pierre Leburton

We describe the electro-thermal transport in metallic carbon nanotubes (m-CNTs) by a semi-classical approach that takes into account the high-field dynamical interdependence between charge carrier and phonon populations. Our model is based on the self-consistent solution of the Boltzmann transport equation and the heat equation mediated by a phonon rate equa

Douglas H. Rudd, Daisuke Nagai

We present high-resolution cosmological hydrodynamic simulations of three galaxy clusters employing a two-temperature model for the intracluster medium. We show that electron temperatures in cluster outskirts are significantly lower than the mean gas temperature, because Coulomb collisions are insufficient to keep electrons and ions in thermal equilibrium. T

Christoph Spengler

The aim of this thesis is to investigate quantum entanglement and quantum nonlocality of bipartite finite-dimensional systems (bipartite qudits). Entanglement is one of the most fascinating non-classical features of quantum theory, and besides its impact on our view of the world, it can be exploited for applications such as quantum cryptography and quantum c

Y. Sheffer, J. X. Prochaska, B. T. Draine, D. A. Perley

GRB 080607 has provided the first strong observational signatures of molecular absorption bands toward any galaxy hosting a gamma-ray burst. Despite the identification of dozens of features as belonging to various atomic and molecular (H_2 and CO) carriers, many more absorption features remained unidentified. Here we report on a search among these features f

Vsevolod A. Vladimirov

A set of traveling wave solution to convection-reaction-diffusion equation is studied by means of methods of local nonlinear analysis and numerical simulation. It is shown the existence of compactly supported solutions as well as solitary waves within this family for wide range of parameter values.

Michael Huber

Let $N=L_n(q)$, {$n \geq 2$}, $q$ a prime power, be a projective linear simple group. We classify all Steiner quadruple systems admitting a group $G$ with $N \leq G \leq \Aut(N)$. In particular, we show that $G$ cannot act as a group of automorphisms on any Steiner quadruple system for $n>2$.

James King, Erik Krohn

A set $G$ of points on a 1.5-dimensional terrain, also known as an $x$-monotone polygonal chain, is said to guard the terrain if any point on the terrain is &#39;seen&#39; by a point in $G$. Two points on the terrain see each other if and only if the line segment between them is never strictly below the terrain. The minimum terrain guarding problem asks for