June 2009 arXiv papers — page 35

I. A. Gudim, E. V. Eremin, V. L. Temerov

Data about stability areas of Nd1-xDyxFe3(BO3)4 trigonal phases in fluxes on the bismuth trimolibdate basis and feature of labile phase dynamics conditions is noted. Group growth conditions of these phases single crystals on seeds and at spontaneous nucleation in a thin layer of flux on crystal carrier are described. Temperature and field dependences of magn

Hiroshi Ozaki, Hiroshi Fukuda, Toshiaki Fujiwara

As shown by Johannes Kepler in 1609, in the two-body problem, the shape of the orbit, a given ellipse, and a given non-vanishing constant angular momentum determines the motion of the planet completely. Even in the three-body problem, in some cases, the shape of the orbit, conservation of the centre of mass and a constant of motion (the angular momentum or t

Chun-Yeol You, Seung-Seok Ha, Hyun-Woo Lee

The temperature increment due to the Joule heating in a nanopillar spin transfer torque system is investigated. We obtain a time dependent analytic solution of the heat conduction equation in nanopillar geometry by using the Green's function method after some simplifications of the problem. While Holm's equation is applicable only to steady states in

Vladimir Dogiel, Dmitrii Chernyshov, Takayuki Yuasa, Dmitrii Prokhorov

We analyse new results of Chandra and Suzaku which found a flux of hard X-ray emission from the compact region around Sgr A$^\ast$ (r ~ 100 pc). We suppose that this emission is generated by accretion processes onto the central supermassive blackhole when an unbounded part of captured stars obtains an additional momentum. As a result a flux of subrelativisti

Tao Zhou, C. S. Ting

We studied the phase diagram for a two-dimensional d-wave superconducting system under an in-plane magnetic field or an exchange field. According to the spatial configuration of the order parameter, we show that there exists quantum phase transitions in which the uniform phase transforms to the one-dimensional Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, a

Galina Nemova, Raman Kashyap

We present a new scheme for a laser cooled Raman optical fiber amplifier. The heat generated in the process of stimulated Raman scattering is compensated for with laser cooling provided by anti-Stokes fluorescence of ytterbium ions doped in the core of the fiber. The device is pumped with two pump sources. One of the pump sources provides Raman amplification

Geunsik Lee, Bongki Lee, Jiyoung Kim, Kyeongjae Cho

We have investigated ozone adsorption on graphene using the ab initio density functional theory method. Ozone molecules adsorb on graphene basal plane with binding energy of 0.25 eV, and the physisorbed molecule can chemically react with graphene to form an epoxide group and an oxygen molecule. The activation energy barrier from physisorption to chemisorptio

Zhongxiao Jia, Datian Niu

The harmonic Lanczos bidiagonalization method can be used to compute the smallest singular triplets of a large matrix $A$. We prove that for good enough projection subspaces harmonic Ritz values converge if the columns of $A$ are strongly linearly independent. On the other hand, harmonic Ritz values may miss some desired singular values when the columns of $

M. Zhao, J. D. Monnier, E. Pedretti, N. Thureau

We present sub-milliarcseond resolution imaging and modeling of two nearby rapid rotators Alpha Cephei and Alpha Ophiuchi, obtained with the CHARA array - the largest optical/IR interferometer in the world. Incorporating a gravity darkening model, we are able to determine the inclination, the polar and equatorial radius and temperature, as well as the fracti

Alfonso Reina, Stefan Thiele, Xiaoting Jia, Sreekar Bhaviripudi

We report graphene films composed mostly of one or two layers of graphene grown by controlled carbon precipitation on the surface of polycrystalline Ni thin films during atmospheric chemical vapor deposition(CVD). Controlling both the methane concentration during CVD and the substrate cooling rate during graphene growth can significantly improve the thicknes

T. Bensby, S. Feltzing, J. A. Johnson, A. Gal-Yam

Measurements based on a large number of red giant stars suggest a broad metallicity distribution function (MDF) for the Galactic bulge, centered on [Fe/H]=-0.1. However, recently, a new opportunity emerged to utilize temporary flux amplification (by factors of ~100 or more) of faint dwarf stars in the Bulge that are gravitationally lensed, making them observ

Thomas Gurry, Ozan Kahramanogullari, Robert G. Endres

Ras GTPases are lipid-anchored G proteins which play a fundamental role in cell signaling processes. Electron micrographs of immunogold-labeled Ras have shown that membrane-bound Ras molecules segregate into nanocluster domains. Several models have been developed in attempts to obtain quantitative descriptions of nanocluster formation, but all have relied on

Valentino Lacquaniti, Giovanni Montani

In this paper we propose a new approach to matter dynamics in compactified Kaluza-Klein theories. We discard the idea that the motion is geodesic and perform a simultaneous reduction of matter geometry defining the test particle via a multipole approach. In the resulting dynamics the tower of huge massive modes is removed, without giving up the compactificat

John F. Dawson, B. Mihaila, F. Cooper

We present numerical solutions of the semi-classical Boltzmann-Vlasov equation for fermion particle-antiparticle production by strong electric fields in boost-invariant coordinates in (1+1) and (3+1) dimensional QED. We compare the Boltzmann-Vlasov results with those of recent quantum field theory calculations and find good agreement. We conclude that extend

Jacek Guzik, Bhuvnesh Jain, Masahiro Takada

Tests of gravity on large-scales in the universe can be made using both imaging and spectroscopic surveys. The former allow for measurements of weak lensing, galaxy clustering and cross-correlations such as the ISW effect. The latter probe galaxy dynamics through redshift space distortions. We use a set of basic observables, namely lensing power spectra, gal

Jose M. Fernandez, David W. Latham, Guillermo Torres, Mark E. Everett

We have derived masses and radii for both components in five short-period single-lined eclipsing binary stars discovered by the TrES wide-angle photometric survey for transiting planets. All these systems consist of a visible F-star primary and an unseen M-star secondary (M_A > 0.8 M_sun, M_B < 0.45 M_sun). The spectroscopic orbital solution combined with a

J. Fernandez Bonder, J. P. Pinasco, A. M. Salort

In this work we study the asymptotic distribution of eigenvalues in one-dimensional open sets. The method of proof is rather elementary, based on the Dirichlet lattice points problem, which enable us to consider sets with infinite measure. Also, we derive some estimates for the the spectral counting function of the Laplace operator on unbounded two-dimension

Maksim Maydanskiy, Paul Seidel

We construct open symplectic manifolds which are convex at infinity (&#34;Liouville manifolds&#34;) and which are diffeomorphic, but not symplectically isomorphic, to cotangent bundles T^*S^{n+1}, for any n+1 \geq 3. These manifolds are constructed as total spaces of Lefschetz fibrations, where the fibre and all but one of the vanishing cycles are fixed. We

Ralph R. Gomez

Negative Sasakian manifolds, where the first Chern class of the contact subbundle is a torsion class, can be viewed as Seifert-$S^1$ bundles where the base orbifold has an ample orbifold canonical class. We use this framework to settle completely an open problem formulated by C.Boyer and K.Galicki which asks whether or not arbitrary connected sums of $S^2\ti

David Pearce, Hans Tompits, Stefan Woltran

Equilibrium logic is an approach to nonmonotonic reasoning that extends the stable-model and answer-set semantics for logic programs. In particular, it includes the general case of nested logic programs, where arbitrary Boolean combinations are permitted in heads and bodies of rules, as special kinds of theories. In this paper, we present polynomial reductio

Andrea Isella, John M. Carpenter, Anneila I. Sargent

We present new sub-arcsecond (0.7&#39;&#39;) Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of the 1.3 mm continuum emission from circumstellar disks around 11 low and intermediate mass pre-main sequence stars. High resolution observations for 3 additional sources were obtained from literature. In all cases the disk emission is

Maksim Maydanskiy

In this paper we construct, in all odd complex dimensions, pairs of Liouville domains W_0 and W_1 which are diffeomorphic to the cotangent bundle of the sphere with one extra subcritical handle, but are not symplectomorphic. While W_0 is symplectically very similar to the cotangent bundle itself, W_1 is more unusual. We use Seidel&#39;s exact triangles for F

The BABAR Collaboration, B. Aubert

We search for a light Higgs boson, $A^0$, in the radiative decay $Υ(3S)\toγA^0$, $A^0\toτ^+τ^-$, $τ^+\to e^+ν_e \barν_τ$ or $τ^+\to μ^+ ν_μ \barν_τ$. The data sample contains 122 million $Υ(3S)$ events recorded with the \babar detector. We find no evidence for a narrow structure in the studied $τ^+τ^-$ invariant mass region of $4.03<m_{τ^+τ^-}<10.10$ \gevcc.

Jaka Cimpric

A method for computing global minima of real multivariate polynomials based on semidefinite programming was developed by N. Z. Shor, J. B. Lasserre and P. A. Parrilo. The aim of this article is to extend a variant of their method to noncommutative symmetric polynomials in variables $X$ and $Y$ satisfying $YX-XY=1$ and $X^\ast=X$, $Y^\ast=-Y$. Global minima o

D. S. L. Abergel, Pekka Pietiläinen, Tapash Chakraborty

A recent surprising finding that electronic compressibility measured experimentally in monolayer graphene can be described solely in terms of the kinetic energy [J. Martin, et al., Nat. Phys. 4, 144 (2008)] is explained theoretically as a direct consequence of the linear energy dispersion and the chirality of massless Dirac electrons. For bilayer graphene we

H. Tian, W. Curdt, L. Teriaca, E. Landi

We study the TR properties above sunspots and the surrounding plage regions, by analyzing several sunspot spectra obtained by SUMER in March 1999 and November 2006. We compare the SUMER spectra observed in the umbra, penumbra, plage, and sunspot plume regions. The Lyman line profiles averaged in each region are presented. For the sunspot observed in 2006, th

S. Das Sarma, Kun Yang

We apply Laughlin&#39;s gauge argument to analyze the $ν=0$ quantum Hall effect observed in graphene when the Fermi energy lies near the Dirac point, and conclude that this necessarily leads to divergent bulk longitudinal resistivity in the zero temperature thermodynamic limit. We further predict that in a Corbino geometry measurement, where edge transport a

Jiajia Zhou, An-Chang Shi

Phase behavior of diblock copolymer/homopolymer blends (AB/C) is investigated theoretically. The study focuses on a special case where all three binary pairs, A/B, B/C and C/A, are miscible. Despite the miscibility of the binary pairs, a closed-loop immiscible region exists in the AB/C blends when the A/C and B/C pair interactions are sufficiently different.

Nathan Smith

The ``Homunculus&#39;&#39; nebula around Eta Carinae is one of our most valuable tools for understanding the extreme nature of episodic pre-supernova mass loss in the most massive stars, perhaps even more valuable than the historical light curve of eta Car. As a young nebula that is still in free expansion, it bears the imprint of its ejection physics, makin

A. B. Kuzmenko, L. Benfatto, E. Cappelluti, I. Crassee

We observe a giant increase of the infrared intensity and a softening of the in-plane antisymmetric phonon mode Eu (~0.2 eV) in bilayer graphene as a function of the gate-induced doping. The phonon peak has a pronounced Fano-like asymmetry. We suggest that the intensity growth and the softening originate from the coupling of the phonon mode to the narrow ele

Nathan Smith, Ryan Chornock, Jeffrey M. Silverman, Alexei V. Filippenko

We present a detailed analysis of the extremely luminous Type IIn supernova SN2006gy using spectra obtained between days 36 and 237 after explosion. We derive the temporal evolution of the effective temperature, radius, expansion speeds, and bolometric luminosity, as well as the progenitor wind density and total swept-up mass overtaken by the shock. SN2006gy

G. Ghisellini, F. Tavecchio, G. Ghirlanda

Among the blazars detected by the Fermi satellite, we have selected the 23 blazars that in the three months of survey had an average gamma-ray luminosity above 1e48 erg/s. For 17 out of the 23 sources we found and analysed X-ray and optical-UV data taken by the Swift satellite. With these data, implemented by archival and not simultaneous data, we construct

T. G. Rappoport, Bruno Uchoa, A. H. Castro Neto

We perform Monte Carlo simulations to study the interplay of structural and magnetic order in single layer graphene covered with magnetic adatoms. We propose that the presence of ripples in the graphene structure can lead to clustering of the adatoms and to a variety of magnetic states such as super-paramagnetism, antiferromagnetism, ferromagnetism and spin

L. Kaltenegger, D. Sasselov

We study the spectrum of a planetary atmosphere to derive detectable features in low resolution of different global geochemical cycles on exoplanets - using the sulphur cycle as our example. We derive low resolution detectable features for first generation space- and ground- based telescopes as a first step in comparative planetology. We assume that the surf

Armando Castro

We prove the ergodic Closing Lemma for Nonsingular Endomorphisms.

Ho-Ung Yee

We consider a simple extension to the previously found gravity solution corresponding to a boost invariant Bjorken plasma, by allowing components that are asymmetric under parity flipping of the spacetime rapidity. Besides the question whether this may have a realization in collisions of different species of projectiles, such as lead-gold collision, our new

Vid Stojevic

We show that the superconformal symmetries of the (1,1) sigma model decompose into a set of more refined symmetries when the target space admits projectors $P_{\pm}$, and the orthogonal complements $Q_{\pm}$, covariantly constant with respect to the two natural torsionful connections $\nabla^{(\pm)}$ that arise in the sigma model. Surprisingly the new symmet

Hyuk-Jae Jang, Ian Appelbaum

Using long-distance lateral devices, spin transport near the interface of Si and its native oxide (SiO2) is studied by spin-valve measurements in an in-plane magnetic field and spin precession measurements in a perpendicular magnetic field at 60K. As electrons are attracted to the interface by an electrostatic gate, we observe shorter average spin transit ti

Richard Herrmann

Based on the Liouville-Weyl definition of the fractional derivative, a new direct fractional generalization of higher order derivatives is presented. It is shown, that the Riesz and Feller derivatives are special cases of this approach.

The Pierre Auger Collaboration, J. Abraham, P. Abreu, M. Aglietta

Studies of the cosmic ray energy spectrum at the highest energies with the Pierre Auger Observatory.

Todd Kemp, Karl Mahlburg, Amarpreet Rattan, Clifford Smyth

A non-crossing pairing on a bitstring matches 1s and 0s in a manner such that the pairing diagram is nonintersecting. By considering such pairings on arbitrary bitstrings $1^{n_1} 0^{m_1} ... 1^{n_r} 0^{m_r}$, we generalize classical problems from the theory of Catalan structures. In particular, it is very difficult to find useful explicit formulas for the e

Jozsef Z. Farkas

We consider a class of physiologically structured population models, a first order nonlinear partial differential equation equipped with a nonlocal boundary condition, with a constant external inflow of individuals. We prove that the linearised system is governed by a quasicontraction semigroup. We also establish that linear stability of equilibrium solution

Cristiana Bertolin

We introduce the notion of extension of 1-motives. Using the dictionary between strictly commutative Picard stacks and complexes of abelian sheaves concentrated in degrees -1 and 0, we check that an extension of 1-motives induces an extension of the corresponding strictly commutative Picard stacks. We compute the Hodge, the de Rham and the l-adic realization

Keiji Saito, Taro Nagao, Sebastian Muller, Petr Braun

We address the quantum-classical correspondence for chaotic systems with a crossover between symmetry classes. We consider the energy level statistics of a classically chaotic system in a weak magnetic field. The generating function of spectral correlations is calculated by using the semiclassical periodic-orbit theory. An explicit calculation up to the seco

Andrea D&#39;Agnolo, Stephane Guillermou, Pierre Schapira

We describe the category of regular holonomic modules over the ring D[[h]] of linear differential operators with a formal parameter h. In particular, we establish the Riemann-Hilbert correspondence and discuss the additional t-structure related to h-torsion.

Ryan M. Wilson, Shai Ronen, John L. Bohn

We explore the structure and dynamics of dipolar Bose-Einstein condensates (DBECs) near their threshold for instability. Near this threshold a DBEC may exhibit nontrivial, biconcave density distributions, which are associated with instability against collapse into &#34;angular roton&#34; modes. Here we discuss experimental signatures of these novel features.

Nicholas M. Ball, Robert J. Brunner

We review the current state of data mining and machine learning in astronomy. &#39;Data Mining&#39; can have a somewhat mixed connotation from the point of view of a researcher in this field. If used correctly, it can be a powerful approach, holding the potential to fully exploit the exponentially increasing amount of available data, promising great scientif

Dimitris G. Angelakis, Li Dai, Leong-Chuan Kwek

We show that coherent control of the steady-state long-distance entanglement between pairs of cavity-atom systems in an array of lossy and driven coupled resonators is possible. The cavities are doped with atoms and are connected through wave guides, other cavities or fibers depending on the implementation. We find that the steady-state entanglement can be c

Giovanni Amelino-Camelia, Niccolo&#39; Loret, Gianluca Mandanici, Flavio Mercati

We modify the Chandrasekhar model of white dwarfs by introducing novel momentum-space features that characterize the analysis of some quantum-spacetime scenarios. We find that the rather standard ultraviolet effects of spacetime quantization can only be significant in a regime where the Chandrasekhar model anyway lacks any contact with observations. But a ne

Steven G. Avery, Borun D. Chowdhury, Samir D. Mathur

It is believed that the D1D5 brane system is described by an &#39;orbifold CFT&#39; at a special point in moduli space. We first develop a general formulation relating amplitudes in a d-dimensional CFT to absorption/emission of quanta from flat infinity. We then construct the D1D5 vertex operators for minimally coupled scalars in supergravity, and use these

J. Kluson, Kamal L. Panigrahi

We study Wilson loops in N=6 superconformal Chern-Simons theory with gauge group $U(M) \times \bar{U(N)}$ that is dual to N M2-branes and (M-N) fractional M2-branes, equivalently, discrete 3-form holonomy at C4/Zk orbifold singularity. We give description of these Wilson loops in terms of macroscopic fundamental string and D6-branes in the dual AdS$_4\times$

Federico R. Urban, Ariel R. Zhitnitsky

We suggest that the solution to the cosmological vacuum energy puzzle is linked to the infrared sector of the effective theory of gravity interacting with standard model fields, with QCD fields specifically. We work in the framework of low energy quantum gravity as an effective field theory. In particular, we compute the vacuum energy in terms of QCD paramet

Edi Halyo

We show that supersymmetric Abelian models that are obtained from deformations of those with ${\cal N}=2$ supersymmetry also contain metastable vacua for a wide range of parameters. The deformations we consider are combinations of masses for charged and singlet fields, a singlet F--term and an anomalous D--term. We find that, in all cases, the nonsupersymmet

Federico R. Urban, Ariel R. Zhitnitsky

We suggest that the solution to the cosmological vacuum energy puzzle is linked to the infrared sector of the effective theory of gravity interacting with standard model fields. We propose a specific solvable two dimensional model where our proposal can be explicitly tested. We analyse the 2d Schwinger model on a 2-torus and in curved 2d space, mostly exploi

Edi Halyo

We describe a mechanism that produces an exponentially small $μ$--term on the world--volumes of D5 branes wrapping a deformed and fibered $A_3$ singularity. The small $μ$ arises due to brane instanton effects which can be calculated after a geometric transition at one of the nodes of the singularity.

T. M. Adamo, E. T. Newman, C. N. Kozameh

Shear-free or asymptotically shear-free null geodesic congruences possess a large number of fascinating geometric properties and to be closely related, in the context of general relativity, to a variety of physically significant affects. It is the purpose of this paper to develop these issues and find applications in GR. The applications center around the pr

Giorgi Japaridze

Computability logic (CoL) (see http://www.cis.upenn.edu/~giorgi/cl.html) is a recently introduced semantical platform and ambitious program for redeveloping logic as a formal theory of computability, as opposed to the formal theory of truth that logic has more traditionally been. Its expressions represent interactive computational tasks seen as games played

Mubasher Jamil, Peter K. F. Kuhfittig, Farook Rahaman, Sk. A Rakib

It is generally agreed that the acceleration of the Universe can best be explained by the presence of dark or phantom energy. The equation of state of the latter shows that the null energy condition is violated. Such a violation is the primary ingredient for sustaining traversable wormholes. This paper discusses wormholes supported by a more general form cal

Zengo Tsuboi

We propose Wronskian-like determinant formulae for the Baxter Q-functions and the eigenvalues of transfer matrices for spin chains related to the quantum affine superalgebra U_{q}(hat{gl}(M|N)). In contrast to the supersymmetric Bazhanov-Reshetikhin formula (the quantum supersymmetric Jacobi-Trudi formula) proposed in [Z. Tsuboi, J. Phys. A: Math. Gen. 30 (1

Ayan Chatterjee

The paper deals with the extension of the Weak Isolated Horizon (WIH) formulation to the non- minimally coupled Holst action. In the first part of the paper, we introduce the non- minimal scalar coupling of the Holst action and construct the covariant phase space of the theory. Using the covariant phase space, we prove the laws of black hole mechanics and sh

Daniel Hennequin, Philippe Verkerk

We examine here the classical dynamics of cold atoms in square optical lattices, i.e. lattices obtained with two orthogonal stationary plane waves. Contrary to much of the past studies in this domain, the potential is here time independent and non dissipative. We show that, as a function of the experimental parameters, very different behaviors are obtained,

Brian Sales, Michael McGuire, Athena Sefat, David Mandrus

A simple two-band model is used to describe the magnitude and temperature dependence of the magnetic susceptibility, Hall coefficient and Seebeck data from undoped and Co doped BaFe2As2. Overlapping, rigid parabolic electron and hole bands are considered as a model of the electronic structure of the FeAs-based semimetals. The model has only three parameters:

Tian De Cao

The spin-singlet superconductivity without phonons is examined in consideration of correlations on an extended Hubbard model. It is shown that the superconductivity requires not only the total correlation should be strong enough but also the density of state around Fermi energy should be large enough, which shows that the high temperature superconductivity c

Bert Schroer

It is often overlooked that local quantum physics has a built in quantum localization structure which may under certain circumstances disagree with (differential, algebraic) geometric ideas. String theory originated from such a spectacular misinterpretation of a source-target embedding in which an inner symmetry of the source object becomes the Lorentz symme

Dane Taylor, Edward Ott, Juan G. Restrepo

We study the synchronization of Kuramoto oscillators with all-to-all coupling in the presence of slow, noisy frequency adaptation. In this paper we develop a new model for oscillators which adapt both their phases and frequencies. It is found that this model naturally reproduces some observed phenomena that are not qualitatively produced by the standard Kura

Y. Laplace, J. Bobroff, F. Rullier-Albenque, D. Colson

75As NMR and susceptiblity were measured in a Ba(Fe1-xCox)2As2 single crystal for x=6%. Nuclear Magnetic Resonance (NMR) spectra and relaxation rates allow to show that all Fe sites experience an incommensurate magnetic ordering below T=31K. Comparison with undoped compound allows to estimate a typical moment of 0.05 muB. Anisotropy of the NMR widths can be

Robin Steinigeweg, Hannu Wichterich, Jochen Gemmer

We consider the increase of the spatial variance of some inhomogeneous, non-equilibrium density (particles, energy, etc.) in a periodic quantum system of condensed matter-type. This is done for a certain class of initial quantum states which is supported by static linear response and typicality arguments. We directly relate the broadening to some current aut

Michal Was, Marie-Anne Bizouard, Violette Brisson, Fabien Cavalier

Time shifting the outputs of Gravitational Wave detectors operating in coincidence is a convenient way to estimate the background in a search for short duration signals. However this procedure is limited as increasing indefinitely the number of time shifts does not provide better estimates. We show that the false alarm rate estimation error saturates with th

Yannick Meyapin, Denys Dutykh, Marguerite Gisclon

In the present study we discuss several modeling issues of powder-snow avalanche flows. We take a two-fluid modeling paradigm. For the sake of simplicity, we will restrict our attention to barotropic equations. We begin the exposition by a compressible model with two velocities for each fluid. However, this model may become non-hyperbolic and thus, represent

Mehmet Koca, Mudhahir Al-Ajmi, Nazife Ozdes Koca

Vertices of the 4-dimensional semi-regular polytope, the \textit{grand antiprism} and its symmetry group of order 400 are represented in terms of quaternions with unit norm. It follows from the icosian representation of the \textbf{$E_{8} $} root system which decomposes into two copies of the root system of $H_{4} $. The symmetry of the \textit{grand antipri

D. Clement, N. Fabbri, L. Fallani, C. Fort

In this work, we use inelastic scattering of light to study the response of inhomogeneous Mott-insulator gases to external excitations. The experimental setup and procedure to probe the atomic Mott states are presented in detail. We discuss the link between the energy absorbed by the gases and accessible experimental parameters as well as the linearity of th

Robin de Jong

Using the discriminant modular form and the Noether formula it is possible to write the admissible self-intersection of the relative dualising sheaf of a semistable hyperelliptic curve over a number field or function field as a sum, over all places, of a certain adelic invariant. We provide a simple geometric interpretation for this invariant, based on the a

Mehmet Koca, Mudhahir Al-Ajmi, Nazife Ozdes Koca

Vertices of the 4-dimensional semi-regular polytope, \textit{snub 24-cell} and its symmetry group $W(D_{4}):C_{3} $ of order 576 are represented in terms of quaternions with unit norm. It follows from the icosian representation of \textbf{$E_{8} $} root system. The quaternionic root system of $H_{4} $ splits as the vertices of 24-cell and the \textit{snub 24

Haïja Moustafa

In this paper, we first remind how we can see the &#34;hull&#34; of the pinwheel tiling as an inverse limit of simplicial complexes (Anderson and Putnam) and we then adapt the PV cohomology introduced in a paper of Bellissard and Savinien to define it for pinwheel tilings. We then prove that this cohomology is isomorphic to the integer Čech cohomology of the

A. Bailey, Th. Schlumprecht, N. Sivakumar

Let $S\subset\R^d$ be a bounded subset with positive Lebesgue measure. The Paley-Wiener space associated to $S$, $PW_S$, is defined to be the set of all square-integrable functions on $\R^d$ whose Fourier transforms vanish outside $S$. A sequence $(x_j:j\kin\N)$ in $\R^d$ is said to be a Riesz-basis sequence for $L_2(S)$ (equivalently, a complete interpolati

Irmina Czarna, Zbigniew Palmowski

Consider two insurance companies (or two branches of the same company) that receive premiums at different rates and then split the amount they pay in fixed proportions for each claim (for simplicity we assume that they are equal). We model the occurrence of claims according to a Poisson process. The ruin is achieved when the corresponding two-dimensional ris

Giovanni M. Marchetti, Monia Lupparelli

We discuss a class of chain graph models for categorical variables defined by what we call a multivariate regression chain graph Markov property. First, the set of local independencies of these models is shown to be Markov equivalent to those of a chain graph model recently defined in the literature. Next we provide a parametrization based on a sequence of g

Panayotis Mertikopoulos, Aris L. Moustakas

We study repeated games where players use an exponential learning scheme in order to adapt to an ever-changing environment. If the game&#39;s payoffs are subject to random perturbations, this scheme leads to a new stochastic version of the replicator dynamics that is quite different from the &#34;aggregate shocks&#34; approach of evolutionary game theory. Ir

Tamas Borzsonyi, Tamas Unger, Balazs Szabo

Refraction and deflection of shear zones in layered granular materials was studied experimentally and numerically. We show, that (i) according to a recent theoretical prediction [T. Unger, Phys. Rev. Lett. 98, 018301 (2007)] shear zones refract in layered systems in analogy with light refraction, (ii) zone refraction obeys Snell&#39;s law known from geometri

Riikka Korte, Juha Lehrbäck, Heli Tuominen

We prove an equivalence result between the validity of a pointwise Hardy inequality in a domain and uniform capacity density of the complement. This result is new even in Euclidean spaces, but our methods apply in general metric spaces as well. We also present a new transparent proof for the fact that uniform capacity density implies the classical integral v

S. Pasini, P. Karbach, C. Raas, G. S. Uhrig

In the framework of nuclear magnetic resonance, we consider the general problem of the coherent control of a spin coupled to a bath by means of composite or continuous pulses of duration $τ_\mathrm{p}$. We show explicity that it is possible to design the pulse in order to achieve a decoupling of the spin from the bath up to the third order in $τ_\mathrm{p}$.

R. Dale, J. A. Morales-Lladosa, D. Saez

We work in the framework of a simple vector-tensor theory. The parametrized post-Newtonian approximation of this theory is identical to that of general relativity. Our attention is focused on cosmology. In an homogeneous isotropic universe, it is proved that the energy density, $ρ_{A}$, of the vector field $A$, and its pressure, $p_{A}$, do not depend on tim

A. Perez

We present recent measurements of the CKM angle alpha using data collected by the BABAR detector at the PEP-II asymmetric-energy e^+e^- collider at the SLAC National Accelerator Laboratory, operating at the Upsilon(4S) resonance. We present constraints on alpha from B->pipi, B->rhorho and B->rhopi decays.

Meni Shay, Amit Keren, Gad Koren, Amit Kanigel

We investigate the coupling between the magnetic and superconducting order parameters in an 8 m long meander line ("wire") made of a La1.94Sr0.06CuO4 film with a cross section of 0.5 x 100 um^2. The magnetic order parameter is determined using the Low-Energy muon spin relaxation technique. The superconducting order parameter is characterized by transport mea

Mehmet Onder, H. Hüseyin Uğurlu

In this paper, using the classifications of timelike and spacelike ruled surfaces, we study the Mannheim offsets of timelike ruled surfaces in Minkowski 3-space. Firstly, we define the Mannheim offsets of a timelike ruled surface by considering the Lorentzian casual character of the offset surface. We obtain that the Mannheim offsets of a timelike ruled surf

Kazufumi Torii, Natsuko Kudo, Motosuji Fujishita, Tokuichi Kawase

Fukui et al. (2006) discovered two huge molecular loops in the Galactic center located in (l, b) ~ (355 deg-359 deg, 0 deg-2 deg) in a large velocity range of -180-40 km s^-1. Following the discovery, we present detailed observational properties of the two loops based on NANTEN 12CO(J=1-0) and 13CO(J=1-0) datasets at 10 pc resolution including a complete set

Yukinobu Adachi

We show that the Jacobian conjecture of the two dimensional case is true.

Subir Ghosh, And Probir Pal

Recently it has been advocated [1] that for describing nature within the minimal symmetry requirement, certain subgroups of Lorentz group may play a fundamental role. One such group is E(2) which induces a Lie algebraic Non-Commutative spacetime [4] where translation invariance is not fully maintained. We have constructed a consistent structure of Non-commut

B. Golli, S. Sirca, M. Fiolhais

We present a method to calculate pion electro-production amplitudes in a coupled-channel framework incorporating quasi-bound quark-model states. The method offers a clear prescription how to extract the resonant part of the amplitudes, even in the presence of different decay channels and a strong mixing of neighbouring resonances. The method is applied to th

Jonathan Bennett, Neal Bez

We use the method of induction-on-scales to prove certain diffeomorphism invariant nonlinear Brascamp--Lieb inequalities. We provide applications to multilinear convolution inequalities and the restriction theory for the Fourier transform, extending to higher dimensions recent work of Bejenaru--Herr--Tataru and Bennett--Carbery--Wright.

S van Strien

In this paper we relate dynamics associated to zero-sum games (Fictitious play) to Hamiltonian dynamics. It turns out that the Hamiltonian dynamics which is induced from fictitious play, has properties which are rather different from those found in more classically defined Hamiltonian dynamics. Although the vectorfield is piecewise constant (and so the flow

Ulf Kuehn

We study the arithmetic self-intersection number of the dualizing sheaf on arithmetic surfaces with respect to morphisms of a particular kind. We obtain upper bounds for the arithmetic self-intersection number of the dualizing sheaf on minimal regular models of the modular curves associated with congruence subgroups $Γ_0(N)$ with square free level, as well a

Christian Brouder, Gianluca Panati, Gabriel Stoltz

A rigorous non perturbative adiabatic approximation of the evolution operator in the many-body physics of degenerate systems is derived. This approximation is used to solve the long-standing problem of the choice of the initial states of H0 leading to eigenstates of H0+V for degenerate systems. These initial states are eigenstates of P0 V P0, where P0 is the

Shuang-Qing Wu

We continue to investigate the separability of massive field equations for spin-0 and spin-1/2 charged particles in the general, non-extremal, rotating, charged, Chong-Cvetic-Lu-Pope black holes with two independent angular momenta and a non-zero cosmological constant in minimal D = 5 gauged supergravity theory. We show that the complex Klein-Gordon equation

Garcia de Andrade

Recently Kleides et al [IJMPA \textbf{11}, 1697 (2008)] found a growing rate for magnetic fields in ideal plasma cosmologies by making use of general relativistic Friedmann model. This growth rate of $\frac{δB}{B}\sim{{(\frac{t}{t_{H}})}^{1/4}}$ indicates the presence of a slow dynamo in the universe. More recently Hasseein [Phys Plasmas (2009)] have also in

Seiju Ohashi, Tetsuya Shiromizu, Sumio Yamada

We reinterpret the proof of the Riemannian Penrose inequality by H. Bray. The modified argument turns out to have a nice feature so that the flow of Riemannian metrics appearing Bray's proof gives a Lorentzian metric of a spacetime. We also discuss a possible extension of our approach to charged black holes.

Pu Zhang, Yi Jin, Sailing He

Inverse transformation optics is introduced, and used to calculate the reflection at the boundary of a transformation medium under consideration. The transformation medium for a practical device is obtained from a two-dimensional (2D) finite embedded coordinate transformation (FECT) which is discontinuous at the boundary. For an electromagnetic excitation of

Raghunandan H. Keshavan, Andrea Montanari, Sewoong Oh

Given a matrix M of low-rank, we consider the problem of reconstructing it from noisy observations of a small, random subset of its entries. The problem arises in a variety of applications, from collaborative filtering (the `Netflix problem&#39;) to structure-from-motion and positioning. We study a low complexity algorithm introduced by Keshavan et al.(2009)

Claude Bardos, Edriss S. Titi

A basic example of shear flow was introduced by DiPerna and Majda to study the weak limit of oscillatory solutions of the Euler equations of incompressible ideal fluids. In particular, they proved by means of this example that weak limit of solutions of Euler equations may, in some cases, fail to be a solution of Euler equations. We use this shear flow examp

The Pierre Auger Collaboration, J. Abraham, P. Abreu, M. Aglietta

Studies of the composition of the highest energy cosmic rays with the Pierre Auger Observatory, including examination of hadronic physics effects on the structure of extensive air showers. Submissions to the 31st ICRC, Lodz, Poland (July 2009).