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Arxiv.org
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[abridged] We report a series of simulations of the formation of a star cluster similar to the Orion Nebula Cluster (ONC), including both radiative transfer and protostellar outflows, and starting from both smooth and self-consistently turbulent initial conditions. Each simulation forms >150 stars and brown dwarfs, yielding a stellar mass distribution from < 0.1 to > 10 Msun. We show that a simulation that begins with self-consistently turbulence embedded in a larger turbulent volume,...
Source: http://arxiv.org/abs/1203.2620v2
Arxiv.org
by R. Giostri; M. Vargas dos Santos; I. Waga; R. R. R. Reis; M. O. Calvão; B. L. Lago
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We use type Ia supernovae (SN Ia) data in combination with recent baryonic acoustic oscillations (BAO) and cosmic microwave background (CMB) observations to constrain a kink-like parametrization of the deceleration parameter ($q$). This $q$-parametrization can be written in terms of the initial ($q_i$) and present ($q_0$) values of the deceleration parameter, the redshift of the cosmic transition from deceleration to acceleration ($z_t$) and the redshift width of such transition ($\tau$). By...
Source: http://arxiv.org/abs/1203.3213v1
Arxiv.org
by L. Feng; B. Inhester; Y. Wei; W. Q. Gan; T. L. Zhang; M. Y. Wang
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The propagation properties of coronal mass ejections (CMEs) are crucial to predict its geomagnetic effect. A newly developed three dimensional (3D) mask fitting reconstruction method using coronagraph images from three viewpoints has been described and applied to the CME ejected on August 7, 2010. The CME's 3D localisation, real shape and morphological evolution are presented. Due to its interaction with the ambient solar wind, the morphology of this CME changed significantly in the early phase...
Source: http://arxiv.org/abs/1203.3261v1
Arxiv.org
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In a recent paper, Gabriel Navarro and Pham Huu Tiep show that the so-called Alperin Weight Conjecture can be verified via the Classification of the Finite Simple Groups, provided any simple group fulfills a very precise list of conditions. Our purpose here is to show that the equivariant refinement of the Alperin's Conjecture for blocks formulated by Geoffrey Robinson in the eighties can be reduced to checking the same statement on any central k*-extension of any finite almost-simple group, or...
Source: http://arxiv.org/abs/1203.3851v3
A hyperbolic type integro-differential equation with two weakly singular kernels is considered together with mixed homogeneous Dirichlet and non-homogeneous Neumann boundary conditions. Existence and uniqueness of the solution is proved by means of Galerkin's method. Regularity estimates are proved and the limitations of the regularity are discussed. The approach presented here is also used to prove regularity of any order for models with smooth kernels, that arise in the theory of linear...
Source: http://arxiv.org/abs/1203.4001v1
Arxiv.org
by Vernon Barger; Muneyuki Ishida; Wai-Yee Keung
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By using the LHC and Tevatron measurements of the cross sections to various decay channels relative to the standard model Higgs boson, the total width of the putative 125 GeV Higgs boson is determined as 6.1 +7.7-2.9 MeV. We describe a way to estimate the branching fraction for Higgs decay to dark matter. We also discuss a No-Go theorem for the gammagamma signal of the Higgs boson at the LHC.
Source: http://arxiv.org/abs/1203.3456v3
Paradoxism
by Florentin Smarandache
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A Florentinís Homonym uses homonyms in an upside-down way, entangling grammar and language rules, defying orthography, loving mistakes, employing tongue hindering; ambiguities of words and senses (homonymic clash); or sentences with two or more homonymic forms put together - either as separate homonymic phrase, or as a chain of homonyms; - and, of course, the eternal humor which helps as does the salt in the food.
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Arxiv.org
by Oriane Aubert; Michael Le Bars; Patrice Le Gal; Philip S. Marcus
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We validate a new law for the aspect ratio $\alpha = H/L$ of vortices in a rotating, stratified flow, where $H$ and $L$ are the vertical half-height and horizontal length scale of the vortices. The aspect ratio depends not only on the Coriolis parameter f and buoyancy (or Brunt-Vaisala) frequency $\bar{N}$ of the background flow, but also on the buoyancy frequency $N_c$ within the vortex and on the Rossby number $Ro$ of the vortex such that $\alpha = f \sqrt{[Ro (1 + Ro)/(N_c^2- \bar{N}^2)]}$....
Source: http://arxiv.org/abs/1203.1562v1
Arxiv.org
by S. Sundar
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Let $A \in M_{n}(\mathbb{R})$ be an invertible matrix. Consider the semi-direct product $\mathbb{R}^{n} \rtimes \mathbb{Z}$ where $\mathbb{Z}$ acts on $\mathbb{R}^{n}$ by matrix multiplication. Consider a strongly continuous action $(\alpha,\tau)$ of $\mathbb{R}^{n} \rtimes \mathbb{Z}$ on a $C^{*}$-algebra $B$ where $\alpha$ is a strongly continuous action of $\mathbb{R}^{n}$ and $\tau$ is an automorphism. The map $\tau$ induces a map $\widetilde{\tau}$ on $B \rtimes_{\alpha} \mathbb{R}^{n}$....
Source: http://arxiv.org/abs/1203.0383v1
Arxiv.org
by Guillermo F. Hagele; Veronica Firpo; Guillermo Bosch; Angeles I. Diaz; Nidia Morrell
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We present a detailed study of the physical properties of the nebular material in four star-forming knots of the blue compact dwarf galaxy Haro 15. Using long-slit and echelle spectroscopy obtained at Las Campanas Observatory, we study the physical conditions (electron density and temperatures), ionic and total chemical abundances of several atoms, reddening and ionization structure, for the global flux and for the different kinematical components. The latter was derived by comparing the oxygen...
Source: http://arxiv.org/abs/1203.0531v1
Arxiv.org
by G. Baumann; K. Galsgaard; Å. Nordlund
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Numerical MHD simulations of 3D reconnection events in the solar corona have improved enormously over the last few years, not only in resolution, but also in their complexity, enabling more and more realistic modeling. Various ways to obtain the initial magnetic field, different forms of solar atmospheric models as well as diverse driving speeds and patterns have been employed. This study considers differences between simulations with stratified and non-stratified solar atmospheres, addresses...
Source: http://arxiv.org/abs/1203.1018v2
Arxiv.org
by Masazumi Honda; Yutaka Yoshida
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We show a large N reduction on S^3 in a BPS sector for a broad class of theories : N>=2 supersymmetric Chern-Simons theory with any number of adjoint and bi-fundamental chiral multiplets.We show that a localization method can be applied to the reduced model and the path integral can be written by a multi-contour integral. By taking a particular localization configuration, we also show that the large N equivalence between the original theory on S^3 and the reduced model holds for the free...
Source: http://arxiv.org/abs/1203.1016v2
Arxiv.org
by T. Wasak; J. Chwedenczuk; P. Zin; M. Trippenbach
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It is demonstrated that measurements of positions of atoms scattered from a quasi-condensate in a Raman process provide information on the temperature of the parent cloud. In particular, the widths of the density and second order correlation functions are sensitive to the phase fluctuations induced by non-zero temperature of the quasi-condensate. It is also shown how these widths evolve during expansion of the cloud of scattered atoms. These results are useful for planning future Raman...
Source: http://arxiv.org/abs/1203.0894v1
Arxiv.org
by Diego Muñoz; Volker Springel; Robert Marcus; Mark Vogelsberger; Lars Hernquist
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Numerous formulations of finite volume schemes for the Euler and Navier-Stokes equations exist, but in the majority of cases they have been developed for structured and stationary meshes. In many applications, more flexible mesh geometries that can dynamically adjust to the problem at hand and move with the flow in a (quasi) Lagrangian fashion would, however, be highly desirable, as this can allow a significant reduction of advection errors and an accurate realization of curved and moving...
Source: http://arxiv.org/abs/1203.1037v1
Arxiv.org
by A. Bazavov; Tanmoy Bhattacharya; C. E. DeTar; H. -T. Ding; Steven Gottlieb; Rajan Gupta; P. Hegde; Urs Heller; F. Karsch; E. Laermann; L. Levkova; Swagato Mukherjee; P. Petreczky; Christian Schmidt; R. A. Soltz; W. Soeldner; R. Sugar; Pavlos M. Vranas
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We calculate the quadratic fluctuations of net baryon number, electric charge and strangeness as well as correlations among these conserved charges in (2+1)-flavor lattice QCD at zero chemical potential. Results are obtained using calculations with tree level improved gauge and the highly improved staggered quark (HISQ) actions with almost physical light and strange quark masses at three different values of the lattice cut-off. Our choice of parameters corresponds to a value of 160 MeV for the...
Source: http://arxiv.org/abs/1203.0784v2
Arxiv.org
by A. Alahmadi; R. E. L. Aldred; R. dela Cruz; P. Solé; C. Thomassen
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Upper and lower bounds are derived for the quantity in the title, which is tabulated for modest values of $n$ and $k.$ An application to graphs with many cycles is given.
Source: http://arxiv.org/abs/1203.0728v1
Arxiv.org
by Mugurel Ţolea; Bogdan Ostahie; Marian Niţă; Felicia Ţolea; Alexandru Aldea
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The phase of the electronic wave function is not directly measurable but, quite remarkably, it becomes accessible in pairs of isospectral shapes, as recently proposed in the experiment of Christopher R. Moon {\it et al.}, Science {\bf 319}, 782 (2008). The method is based on a special property, called transplantation, which relates the eigenfunctions of the isospectral pairs, and allows to extract the phase distributions, if the amplitude distributions are known. We numerically simulate such a...
Source: http://arxiv.org/abs/1203.0717v1
Arxiv.org
by Wolfgang Steiner; Jörg Thuswaldner
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An integral self-affine tile is the solution of a set equation $\mathbf{A} \mathcal{T} = \bigcup_{d \in \mathcal{D}} (\mathcal{T} + d)$, where $\mathbf{A}$ is an $n \times n$ integer matrix and $\mathcal{D}$ is a finite subset of $\mathbb{Z}^n$. In the recent decades, these objects and the induced tilings have been studied systematically. We extend this theory to matrices $\mathbf{A} \in \mathbb{Q}^{n \times n}$. We define rational self-affine tiles as compact subsets of the open subring...
Source: http://arxiv.org/abs/1203.0758v1
Arxiv.org
by Joseph Losby; Jacob A. J. Burgess; Zhu Diao; David C. Fortin; Wayne K. Hiebert; Mark R. Freeman
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We report on the fabrication of sensitive nanotorsional resonators, which can be utilized as magnetometers for investigating the magnetization dynamics in small magnetic elements. The thermo-mechanical noise is calibrated with the resonator displacement in order to determine the ultimate mechanical torque sensitivity of the magnetometer.
Source: http://arxiv.org/abs/1203.0998v1
Arxiv.org
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We investigate here the particle acceleration and collisions with extremely large center of mass energies in a perfectly regular spacetime containing neither singularity nor an event horizon. The ultra-high energy collisions of particles near the event horizon of extremal Kerr blackhole, and also in many other examples of extremal blackholes have been investigated and reported recently. We studied an analogous particle acceleration process in the Kerr and Reissner-Nordstrom spacetimes without...
Source: http://arxiv.org/abs/1203.1803v2
Arxiv.org
by Ekaterina Ilinova; Andrei Derevianko
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We explore the possibility of decelerating and Doppler cooling an ensemble of tree-level $\Lambda$-type atoms by a coherent train of short, non-overlapping laser pulses. We show that $\Lambda$-atoms can be Doppler cooled without additional repumping of the population from the intermediate ground state. We derive analytical expression for the scattering force in the quasi-steady-state regime and analyze its dependence on pulse train parameters. Based on this analysis we propose a method of...
Source: http://arxiv.org/abs/1203.1963v3
Arxiv.org
by Sahin Buyukdagli; Tapio Ala-Nissila
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The remarkably low experimental values of the capacitance data of carbon based materials in contact with water solvent needs to be explained from a microscopic theory in order to optimize the efficiency of these materials. We show that this experimental result can be explained by the dielectric screening deficiency of the electrostatic potential, which in turn results from the interfacial solvent depletion effect driven by image dipole interactions. We show this by deriving from the microscopic...
Source: http://arxiv.org/abs/1203.2285v1
Arxiv.org
by A. O. Sorokin; A. V. Syromyatnikov
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We carry out Monte-Carlo simulations to discuss critical properties of a classical two-dimensional XY frustrated helimagnet on a square lattice. We find two successive phase transitions upon the temperature decreasing: the first one is associated with breaking of a discrete Z_2 symmetry and the second one is of the Berezinskii-Kosterlitz-Thouless (BKT) type at which the SO(2) symmetry breaks. Thus, a narrow region exists on the phase diagram between lines of the Ising and the BKT transitions...
Source: http://arxiv.org/abs/1203.2235v1
Arxiv.org
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The purpose of this paper is to prove the uniqueness theorem of solutions of eigenvalue equations on one end of Riemannian manifolds for drift Laplacians, including the standard Laplacian as a special case; we shall impose "a sort of radiation condition" at infinity on solutions. We shall also provide several Riemannian manifolds whose Laplacians satisfy the absence of embedded eigenvalues and besides the absolutely continuity, although growth orders of their metrics on ends are very...
Source: http://arxiv.org/abs/1203.2310v1
Arxiv.org
by E. Jespers; M. H. Shahzamanian
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We associate a graph ${\mathcal N}_{S}$ with a semigroup $S$ (called the upper non-nilpotent graph of $S$). The vertices of this graph are the elements of $S$ and two vertices are adjacent if they generate a semigroup that is not nilpotent (in the sense of Malcev). In case $S$ is a group this graph has been introduced by A. Abdollahi and M. Zarrin and some remarkable properties have been proved. The aim of this paper is to study this graph (and some related graphs, such as the non-commuting...
Source: http://arxiv.org/abs/1203.2428v1
Arxiv.org
by Qingping Zeng; Qiaofen Jiang; Huaijie Zhong
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Burgos, Kaidi, Mbekhta and Oudghiri provided an affirmative answer to a question of Kaashoek and Lay and proved that an operator $F$ is power finite rank if and only if $\sigma_{dsc}(T+F) =\sigma_{dsc}(T)$ for every operator $T$ commuting with $F$. Later, several authors extended this result to the essential descent spectrum, the left Drazin spectrum and the left essentially Drazin spectrum. In this paper, using the theory of operator with eventual topological uniform descent and the technique...
Source: http://arxiv.org/abs/1203.2442v1
Arxiv.org
by Minoru Kubota
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The quantized vortex state appearing in the recently discovered new states in hcp 4He since their discovery is discussed. Special attention is given to evidence for the vortex state as the vortex fluid (VF) state and its transition into the supersolid (SS) state. Its features are described. The historical expla- nations for the SS state in quantum solids such as solid 4He were based on the idea of Bose Einstein Condensation (BEC) of the imperfections such as va- cancies, interstitials and other...
Source: http://arxiv.org/abs/1203.6824v1
Arxiv.org
by Ruoshi Yuan; Ping Ao
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Recently, a novel framework to handle stochastic processes has emerged from a series of studies in biology, showing situations beyond 'It\^o versus Stratonovich'. Its internal consistency can be demonstrated via the zero mass limit of a generalized Klein-Kramers equation. Moreover, the connection to other integrations becomes evident: the obtained Fokker-Planck equation defines a new type of stochastic calculus that in general differs from the {\alpha}-type interpretation. A unique advantage of...
Source: http://arxiv.org/abs/1203.6600v3
Arxiv.org
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A cocycle $\Omega: P \times G \to H$ taking values in a Lie group $H$ for a free right action of $G$ on $P$ defines a principal bundle $Q$ with the structure group $H$ over $P/G.$ The Chern character of a vector bundle associated to $Q$ defines then characteristic classes on $X.$ This observation becomes useful in the case of infinite dimensional groups. It typically happens that a representation of $G$ is not given by linear operators which differ from the indentity by a trace-class operator....
Source: http://arxiv.org/abs/1203.0245v2
Arxiv.org
by Roman Pöschl; on behalf of the CALICE Collaboration
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The CALICE collaboration is preparing large scale prototypes for highly granular calorimeters for detectors to be operated at a future linear electron positron collider. Currently a prototype of a SiW electromagnetic calorimeter is assembled which in terms of dimensions and layout meets already most of the requirements given by the linear collider physics program and hence the detector design.
Source: http://arxiv.org/abs/1203.0249v1
Deb Cotton Secondline Collection
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Source: https://www.youtube.com/watch?v=crQ2UMNhQwM Uploader: BigRedCotton Upload date: 20121008
Topics: Youtube, video, Music, Second line, brass band, parade, New Orleans, jazz, brass music, live music...
Deb Cotton Secondline Collection
movies

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Super Sunday 2012, Young Men Olymipian Jr. and the Hot 8 Brass Band rolling thru Central City playing Michael Jackson's 'Working Day and Night' Source: https://www.youtube.com/watch?v=CQmpCHlvzH0 Uploader: BigRedCotton Upload date: 20120318
Topics: Youtube, video, Music, Hot 8 Brass Band, New Orleans, Got Me Working Day and Night, Michael...
rolling down Claiborne Ave. Featuring Tucker Source: https://www.youtube.com/watch?v=V33yB_YmMVY Uploader: BigRedCotton Upload date: 20121116
Topics: Youtube, video, Music, Treme, Second line, brass band, parade, New Orleans, jazz, brass music, live...
Arxiv.org
by Maxim Vashkevich; Alexander Petrovsky
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A fast Discrete Cosine Transform (DCT) algorithm is introduced that can be of particular interest in image processing. The main features of the algorithm are regularity of the graph and very low arithmetic complexity. The 16-point version of the algorithm requires only 32 multiplications and 81 additions. The computational core of the algorithm consists of only 17 nontrivial multiplications, the rest 15 are scaling factors that can be compensated in the post-processing. The derivation of the...
Source: http://arxiv.org/abs/1203.3442v2
Arxiv.org
by Anna De Masi; Errico Presutti; Dimitrios Tsagkarogiannis; Maria Eulalia Vares
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We consider the symmetric simple exclusion process in the interval $\La_N:=[-N,N]\cap\mathbb Z$ with births and deaths taking place respectively on suitable boundary intervals $I_+$ and $I_-$, as introduced in De Masi et al. (J. Stat. Phys. 2011). We study the stationary measure density profile in the limit $N\to\infty$
Source: http://arxiv.org/abs/1203.1795v1
Arxiv.org
by S. Liu; P. E. Nissen; W. J. Schuster; G. Zhao; Y. Q. Chen; Y. C. Liang
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The differences between the neutron-capture element abundances of halo stars are important to our understanding of the nucleosynthesis of elements heavier than the iron group. We present a detailed abundance analysis of carbon and twelve neutron-capture elements from Sr up to Pb for a peculiar halo star G24-25 with [Fe/H] = -1.4 in order to probe its origin. The equivalent widths of unblended lines are measured from high resolution NOT/FIES spectra and used to derive abundances based on Kurucz...
Source: http://arxiv.org/abs/1203.5682v1
Deb Cotton Secondline Collection
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Source: https://www.youtube.com/watch?v=Hs9qqKdS_gU Uploader: BigRedCotton Upload date: 20120527
Topics: Youtube, video, Entertainment, New Orleans, Stooges Brass Band, second line parade, debcotton,...
Deb Cotton Secondline Collection
by BigRedCotton
movies

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T-Ray Roberts and another rooftop flow artist at the final stop of the Single Ladies parade Source: https://www.youtube.com/watch?v=z9BzOahajj4 Uploader: BigRedCotton Upload date: 20120424
Topics: Youtube, video, Entertainment, Taray Roberts, New Orleans, Second line parade, debcotton,...
Deb Cotton Secondline Collection
by BigRedCotton
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Source: https://www.youtube.com/watch?v=_bYKZBVoU3Y Uploader: BigRedCotton Upload date: 20121107
Topics: Youtube, video, Music, Second line, brass band, parade, New Orleans, jazz, brass music, live music...
Deb Cotton Secondline Collection
by BigRedCotton
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Money Wasters 2012 Second Line Parade Source: https://www.youtube.com/watch?v=qKpicwhK62U Uploader: BigRedCotton Upload date: 20120528
Topics: Youtube, video, Entertainment, New Orleans, Second Line parade, Treme, TBC Brass Band, To Be...
Deb Cotton Secondline Collection
by BigRedCotton
movies

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Source: https://www.youtube.com/watch?v=gh89doPsbdY Uploader: BigRedCotton Upload date: 20120923
Topics: Youtube, video, Entertainment, clip, 2012, 09, 23, 12, 27, 58, debcotton,...
Deb Cotton Secondline Collection
by BigRedCotton
movies

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Source: https://www.youtube.com/watch?v=pzHNpyGJpyA Uploader: BigRedCotton Upload date: 20120411
Topics: Youtube, video, Music, clip, 2012, 01, 22, 11, 27, 05, debcotton, debcottonsecondlinecollection,...
Deb Cotton Secondline Collection
by BigRedCotton
movies

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Source: https://www.youtube.com/watch?v=Sw9PGiJLjac Uploader: BigRedCotton Upload date: 20120521
Topics: Youtube, video, Entertainment, clip, 2012, 05, 20, 13, 03, 55, debcotton,...
Arxiv.org
by Andreas Schäfer; Jian Zhou
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We reexamine the scale dependence of the ETQS (Efremov-Teryaev-Qiu-Sterman) twist-3 matrix element which has been studied already by the four different groups with conflicting results Ref.[1-4]. We find that we can in fact reproduce the results of Ref.[4] with the method Ref.[4] when we treat some subtleties with greater care, thus easing the mentioned conflict.
Source: http://arxiv.org/abs/1203.5293v1
We use the framework of the HIJING/B\=B v2.0 model to simulate high-multiplicity (HM) $p+p$ collision events at the Large Hadron Collider (LHC) to study observables sensitive to possible collective phenomena, such as strong longitudinal color fields (SLCF) modeled by an enhanced string tension ($\kappa$). We focus on the hyperon/meson yield ratios at center-of-mass (c.m.) energy $\sqrt{s}$ = 7 TeV, in the transverse momentum region, $1 < p_T < 4 $ GeV/{\it c}. For minimum bias events...
Source: http://arxiv.org/abs/1203.6679v2
Arxiv.org
by Andre Chatzistamatiou
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We prove the following criterion for the pro-representability of the deformation cohomology of a commutative formal Lie group. Let f be a flat and separated morphism between noetherian schemes. Assume that the target of f is flat over the integers. For a commutative formal Lie group E, we have the deformation cohomology of f with coefficients in E at our disposal. If the higher direct images of the tangent space of E are locally free and of finite rank then the deformation cohomology is...
Source: http://arxiv.org/abs/1203.4926v3
Arxiv.org
by Pierre-Vincent Koseleff; Daniel Pecker
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The harmonic knot $H(a,b,c)$ is parameterized as $K(t)= (T_a(t), T_b (t), T_c (t))$ where $a$, $b$ and $c$ are relatively coprime integers and $T_n$ is the degree $n$ Chebyshev polynomial of the first kind. We classify the harmonic knots $H(a,b,c)$ for $ a \le 4$. We show that the knot $H(2n-1, 2n, 2n+1)$ is isotopic to $H(4,2n-1, 2n+1)$ (up to mirror symmetry). We study the knots $H(5,n,n+1)$ and give a table of the simplest harmonic knots.
Source: http://arxiv.org/abs/1203.4376v1
Arxiv.org
by Luca Becchetti; Andrea Clementi; Francesco Pasquale; Giovanni Resta; Paolo Santi; Riccardo Silvestri
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Performance bounds for opportunistic networks have been derived in a number of recent papers for several key quantities, such as the expected delivery time of a unicast message, or the flooding time (a measure of how fast information spreads). However, to the best of our knowledge, none of the existing results is derived under a mobility model which is able to reproduce the power law+exponential tail dichotomy of the pairwise node inter-contact time distribution which has been observed in...
Source: http://arxiv.org/abs/1107.5241v3
Deb Cotton Secondline Collection
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Hassan Goffner and Glenn Andrews on snare in the back row, TBC rolling thru Treme on Tuba Fats Tuesday 2012 Source: https://www.youtube.com/watch?v=5Fb4OCtQoaI Uploader: BigRedCotton Upload date: 20120511
Topics: Youtube, video, Entertainment, TBC Brass Band, New Orleans, Treme, debcotton,...
Deb Cotton Secondline Collection
by BigRedCotton
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Source: https://www.youtube.com/watch?v=EhMDOJ5UCyQ Uploader: BigRedCotton Upload date: 20120212
Topics: Youtube, video, News & Politics, clip, 2012, 02, 05, 14, 49, 51, debcotton,...
Arxiv.org
by Volodymyr Mazorchuk; Benjamin Steinberg
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In this paper we discuss various aspects of the problem of determining the minimal dimension of an injective linear representation of a finite semigroup over a field. We outline some general techniques and results, and apply them to numerous examples.
Source: http://arxiv.org/abs/1107.1413v3
Arxiv.org
by H. F. Chau; C. -K. Li; Y. -T. Poon; N. -S. Sze
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Recently, Chau [Quant. Inform. & Comp. 11, 721 (2011)] showed that one can define certain metrics and pseudo-metrics on U(n), the group of all $n\times n$ unitary matrices, based on the arguments of the eigenvalues of the unitary matrices. More importantly, these metrics and pseudo-metrics have quantum information theoretical meanings. So it is instructive to study this kind of metrics and pseudo-metrics on U(n). Here we show that any symmetric norm on ${\mathbb R}^n$ induces a metric on...
Source: http://arxiv.org/abs/1107.1047v2
Arxiv.org
by Elbert E. M. Chia; D. Springer; Saritha K. Nair; X. Q. Zou; S. A. Cheong; C. Panagopoulos; T. Tamegai; H. Eisaki; S. Ishida; S. Uchida; A. J. Taylor; Jian-Xin Zhu
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Using ultrafast optical techniques, we detect two types of bosons strongly coupled to electrons in the family of Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ from the underdoped to overdoped regimes. The different doping dependences of the electron-boson coupling strengths enables us to identify them as phonons and spin fluctuations: electron-phonon coupling ($\lambda_{e-ph}$) peaks at optimal doping, and electron-spin fluctuation coupling ($\lambda_{e-sf}$) decreases monotonically with doping....
Source: http://arxiv.org/abs/1107.1924v2
Arxiv.org
by Changhyun Ahn; Jinsub Paeng; Kyungsung Woo
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The internal 4-form field strengths with 7-dimensional indices have been constructed by de Wit and Nicolai in 1986. They are determined by the following six quantities: the 56-bein of 4-dimensional N=8 gauged supergravity, the Killing vectors on the round seven-sphere, the covariant derivative acting on these Killing vectors, the warp factor, the field strengths with 4-dimensional indices and the 7-dimensional metric. In this paper, by projecting out the remaining mixed 4-form field strengths...
Source: http://arxiv.org/abs/1107.0640v2
Arxiv.org
by Jason Matthews; David Sánchez; Marcus Larsson; Heiner Linke
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The response of electric devices to an applied thermal gradient has, so far, been studied almost exclusively in two-terminal devices. Here we present measurements of the response to a thermal bias of a four-terminal, quasi-ballistic junction with a central scattering site. We find a novel transverse thermovoltage measured across isothermal contacts. Using a multi-terminal scattering model extended to the weakly non-linear voltage regime, we show that the device's response to a thermal bias can...
Source: http://arxiv.org/abs/1107.3179v3
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by Ted Jacobson
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Although the circular photon orbit and ISCO for the Kerr black hole remain distinct from each other and from the horizon in the extremal spin limit on a constant Boyer-Lindquist time slice, on a horizon-crossing slice they both coincide with the null generators of the horizon.
Source: http://arxiv.org/abs/1107.5081v2
Arxiv.org
by L. V. Bork; D. I. Kazakov; G. S. Vartanov
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In this paper we develop a supersymmetric version of unitarity cut method for form factors of operators from the chiral truncation of the the $\mathcal{N}=4$ stress-tensor current supermultiplet $T^{AB}$. The relation between the superform factor with supermomentum equals to zero and the logarithmic derivative of the superamplitude with respect to the coupling constant is discussed and verified at tree- and one-loop level for any MHV $n$-point ($n \geq 4$) superform factor involving operators...
Source: http://arxiv.org/abs/1107.5551v3
Arxiv.org
by Friedemann Brock; Francesco Chiacchio; Anna Mercaldo
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This paper deals with weighted isoperimetric inequalities relative to cones of $\mathbb{R}^{N}$. We study the structure of measures that admit as isoperimetric sets the intersection of a cone with balls centered at the vertex of the cone. For instance, in case that the cone is the half-space $\mathbb{R}_{+}^{N}={x \in \mathbb{R}^{N} : x_{N}>0}$ and the measure is factorized, we prove that this phenomenon occurs if and only if the measure has the form $d\mu=ax_{N}^{k}\exp(c|x|^{2})dx $, for...
Source: http://arxiv.org/abs/1107.5406v4
beautiful!! Source: https://www.youtube.com/watch?v=grgEgb4CcDE Uploader: BigRedCotton Upload date: 20120227
Topics: Youtube, video, News & Politics, Stooges Brass Band, New Orleans, Second Line Parade, Ninth...
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The angular and polarization properties of the photon pair emitted in the two--photon decay of $2s$ hyperfine states in hydrogenlike ions are investigated within the relativistic Dirac framework and second order perturbation theory. The studied transitions are $2s_{1/2}\,(F=1,0)\to1s_{1/2}\,(F=1,0)$ in Hydrogen atom and $2s_{1/2}\,(F=4,3)\to1s_{1/2}\,(F=4,3)$ in hydrogenlike Uranium ion. Two different emission patterns are found: For non-spin-flip transitions, the angular correlation ($i.e.$...
Source: http://arxiv.org/abs/1203.6601v1
Source: https://www.youtube.com/watch?v=4A3R2BnG98A Uploader: BigRedCotton Upload date: 20121008
Topics: Youtube, video, Music, Second line, brass band, parade, New Orleans, jazz, brass music, live music...
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by Sandra Etoka; Malcolm D. Gray; Gary A. Fuller
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MERLIN phase-referenced polarimetric observations towards the W51 complex were carried out in March 2006 in the Class II methanol maser transition at 6.668 GHz and three of the four excited OH maser hyperfine transitions at 6 GHz. Methanol maser emission is found towards both W51 Main and South. We did not detect any emission in the excited OH maser lines at 6.030 and 6.049 GHz down to a 3 sigma limit of ~20 mJy per beam. Excited OH maser emission at 6.035 GHz is only found towards W51 Main....
Source: http://arxiv.org/abs/1203.2527v1
Arxiv.org
by P. S. Burada; B. Lindner
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We study the dynamics of an active Brownian particle with a nonlinear friction function located in a spatial cubic potential. For strong but finite damping, the escape rate of the particle over the spatial potential barrier shows a nonmonotonic dependence on the noise intensity. We relate this behavior to the fact that the active particle escapes from a limit cycle rather than from a fixed point and that a certain amount of noise can stabilize the sojourn of the particle on this limit cycle.
Source: http://arxiv.org/abs/1203.6814v1
Andrea Callard
by Andrea Callard
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The ink disappears when Ken Hampshire drives this American Shredding machine to military or courtroom clients. No readable characters remain after a day of loading and destroying paper documents.
Topic: American Shredding, Green Planet 21, andrea callard
Arxiv.org
by Niko Jokela; Matti Jarvinen; Matthew Lippert
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We analyze the neutral spectrum of the holographic quantum Hall fluid described by the D2-D8' model. As expected for a quantum Hall state, we find the system to be stable and gapped and that, at least over much of the parameter space, the lowest excitation mode is a magneto-roton. In addition, we find magneto-rotons in higher modes as well. We show that these magneto-rotons are direct consequences of level crossings between vector and scalar modes.
Source: http://arxiv.org/abs/1107.3836v2
Deb Cotton Secondline Collection
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Super Sunday 2012, Young Men Olympian Jr. and the Hot 8 Brass Band at the end of the parade. Towards the end, Mayor Mitch Landrieu joins in the shake down Source: https://www.youtube.com/watch?v=q1771cWKT_M Uploader: BigRedCotton Upload date: 20120318
Topics: Youtube, video, Music, Hot 8 Brass Band, New Orleans, second line parade, Mayor Mitch Landrieu,...
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by A. E. Koudou; P. Vallois
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We define Letac-Wesolowski-Matsumoto-Yor (LWMY) functions as decreasing functions from $(0,\infty)$ onto $(0,\infty)$ with the following property: there exist independent, positive random variables $X$ and $Y$ such that the variables $f(X+Y)$ and $f(X)-f(X+Y)$ are independent. We prove that, under additional assumptions, there are essentially four such functions. The first one is $f(x)=1/x$. In this case, referred to in the literature as the Matsumoto-Yor property, the law of $X$ is generalized...
Source: http://arxiv.org/abs/1203.0381v1
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by Pedro Ruiz-Femenia
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The recent developments on the computation of non-resonant corrections to the e+ e- -> W+ W- b bbar cross section in the top-antitop resonance region are reviewed in this talk. Non-resonant production of the final state W+ W- b bbar starts to contribute at NLO in the nonrelativistic power-counting v ~ alpha_s ~ sqrt(alpha_EW). The corrections induced by non-resonant effects reduce the cross section in the top-antitop resonance peak region at a level which is comparable to the expected...
Source: http://arxiv.org/abs/1203.0934v1
Arxiv.org
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In this article, we study stochastic partial differential equations with two reflecting walls, driven by space-time white noise with non-constant diffusion coefficients under periodic boundary conditions. The existence and uniqueness of invariant measures is established under appropriate conditions. The strong Feller property is also obtained.
Source: http://arxiv.org/abs/1203.6818v1
Arxiv.org
by Gábor Czédli; Miklós Maróti; A. B. Romanowska
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Let F be a subfield of the field R of real numbers. Equipped with the binary arithmetic mean operation, each convex subset C of F^n becomes a commutative binary mode, also called idempotent commutative medial (or entropic) groupoid. Let C and C' be convex subsets of F^n. Assume that they are of the same dimension and at least one of them is bounded, or F is the field of all rational numbers. We prove that the corresponding idempotent commutative medial groupoids are isomorphic iff the affine...
Source: http://arxiv.org/abs/1203.5054v1
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by Spyros Basilakos; Athina Pouri
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We place tight constraints on the growth index $\gamma$ by using the recent growth history results of 2dFGRS, SDSS-LRG, VIMOS-VLT deep Survey (VVDS) and {\em WiggleZ} datasets. In particular, we investigate several parametrizations of the growth index $\gamma(z)$, by comparing their cosmological evolution using observational growth rate data at different redshifts. Utilizing a standard likelihood analysis we find that the use of the combined growth data provided by the 2dFGRS, SDSS-LRG, VVDS...
Source: http://arxiv.org/abs/1203.6724v2
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by Martín Huarte-Espinosa; Adam Frank; Bruce Balick; Eric G. Blackman; Orsola De Marco; Joel H. Kastner; Raghvendra Sahai
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The majority of Proto-planetary nebulae (PPN) are observed to have bipolar morphologies. The majority of mature PN are observed to have elliptical shapes. In this paper we address the evolution of PPN/PN morphologies attempting to understand if a transition from strongly bipolar to elliptical shape can be driven by changes in the parameters of the mass loss process. To this end we present 2.5D hydrodynamical simulations of mass loss at the end stages of stellar evolution for intermediate mass...
Source: http://arxiv.org/abs/1107.0415v2
Occupy Wall Street Flickr Archive
by Lily Rothrock
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Topics: owswest, occupy, occupy wall street, j20, ows, occupysf, protest, san francisco
Source: http://www.flickr.com/photos/lilyrhoads/6734925603/
Arxiv.org
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We reanalyze the Fermi spectra of the Geminga and Vela pulsars. We find that the spectrum of Geminga above the break is exceptionally well approximated by a simple power law without the exponential cut-off, making Geminga's spectrum similar to that of Crab. Vela's broadband gamma-ray spectrum is equally well fit with both the exponential cut-off and the double power law shapes. In the broadband double power-law fits, for a typical Fermi spectrum of a bright \gamma-ray pulsar, most of the errors...
Source: http://arxiv.org/abs/1203.1860v1
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by T. K. Komatsubara
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Recent results and future prospects of the particle physics experiments with neutral and charged K-meson (kaon) decays are reviewed. Topics include CP violation, rare decays, leptons in kaon decays, tests of CPT and quantum mechanics, radiative decays, hadrons in kaon decays, basic observables, Vus and CKM unitarity, and exotic searches. Experimental techniques developed for the kaon decay experiments are discussed.
Source: http://arxiv.org/abs/1203.6437v1
Arxiv.org
by Jian-Feng Li; Hong-Tao Feng; Yu Jiang; Wei-Min Sun; Hong-Shi Zong
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We study dynamical chiral symmetry breaking (DCSB) in an effective QED$_{3}$ theory of d-wave high temperature cuprate superconductors under a uniform magnetic field. At zero temperature, the external magnetic field induces a mixed state by generating vortices in the condensate of charged holons. The growing magnetic field suppresses the superfluid density and thus reduces the gauge field mass which is opened via the Anderson-Higgs mechanism. By numerically solving the Dyson-Schwinger gap...
Source: http://arxiv.org/abs/1203.6423v1
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by Johannes Noller
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We consider generalized chameleon models where the conformal coupling between matter and gravitational geometries is not only a function of the chameleon field \phi, but also of its derivatives via higher order co-ordinate invariants. Specifically we consider the first such non-trivial conformal factor A(\phi,X), where X is the canonical kinetic term for \phi. The associated phenomenology is investigated and we show that such theories have a new generic mass-altering mechanism, potentially...
Source: http://arxiv.org/abs/1203.6639v1
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by Vassili Kolokoltsov; Wei Yang
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This paper has a two-folded purpose. First, we attempt to outline the development of the turnpike theorems in the the last several decades. Second, we study turnpike theorems in finite-horizon two-person zero-sum Markov games on a general Borel state space. Utilising the Bellman (or Shapley) operator defined for this game, we prove the stochastic versions of the early turnpike theorem on the set of optimal strategies and the middle turnpike theorem on the distribution of the state space.
Source: http://arxiv.org/abs/1203.6553v1
Arxiv.org
by Morgan W. Mitchell; Marco Koschorreck; Marcin Kubasik; Mario Napolitano; Robert J. Sewell
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An extensive debate on quantum non-demolition (QND) measurement, reviewed in Grangier et al. [Nature, {\bf 396}, 537 (1998)], finds that true QND measurements must have both non-classical state-preparation capability and non-classical information-damage tradeoff. Existing figures of merit for these non-classicality criteria require direct measurement of the signal variable and are thus difficult to apply to optically-probed material systems. Here we describe a method to demonstrate both...
Source: http://arxiv.org/abs/1203.6584v1
Arxiv.org
by Yannick Chevalier; Mounira Kourjieh
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We present in this paper a new procedure to saturate a set of clauses with respect to a well-founded ordering on ground atoms such that A < B implies Var(A) {\subseteq} Var(B) for every atoms A and B. This condition is satisfied by any atom ordering compatible with a lexicographic, recursive, or multiset path ordering on terms. Our saturation procedure is based on a priori ordered resolution and its main novelty is the on-the-fly construction of a finite complexity atom ordering. In contrast...
Source: http://arxiv.org/abs/1203.2809v1
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by Vassilios Gregoriades
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We present the effective version of the theorem about turning Borel sets in Polish spaces into clopen sets while preserving the Borel structure of the underlying space. We show that under some conditions the emerging parameters can be chosen in a hyperarithmetical way and using this we prove a uniformity result.
Source: http://arxiv.org/abs/1203.6874v1
We present the results of a search for pair production of scalar bottom quarks ($\tilde b_1$) and scalar third-generation leptoquarks ($LQ_3$) in a data sample of 5.2 $fb^{-1}$ collected by the D0 experiment at the Tevatron, the $p\bar{p}$ collider at Fermilab. We assume that sbottoms decay to a neutralino ($\tilde \chi^0_1$) and a b quark, and we set 95% C.L. lower limits on their production in the ($m_{\tilde b_1}$, $m_{\tilde \chi^0_1}$) mass plane such that $m_{\tilde b_1} > 247$ GeV for...
Source: http://arxiv.org/abs/1203.6800v1
Arxiv.org
by Mohsen Sardari; Ahmad Beirami; Faramarz Fekri
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Recently, the existence of considerable amount of redundancy in the Internet traffic has stimulated the deployment of several redundancy elimination techniques within the network. These techniques are often based on either packet-level Redundancy Elimination (RE) or Content-Centric Networking (CCN). However, these techniques cannot exploit sub-packet redundancies. Further, other alternative techniques such as the end-to-end universal compression solutions would not perform well either over the...
Source: http://arxiv.org/abs/1203.6864v1
Arxiv.org
by Jesper Levinsen; Pietro Massignan; Frédéric Chevy; Carlos Lobo
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We consider the properties of a single impurity immersed in a Fermi sea close to an interspecies p-wave Feshbach resonance. We calculate its dispersion and spectral response to a radiofrequency pulse. In the presence of a magnetic field, dipolar interactions split the resonance and lead to the appearance of two novel features with respect to the s-wave case: a third polaron branch in the excitation spectrum, in addition to the usual attractive and repulsive ones; and an anisotropic dispersion...
Source: http://arxiv.org/abs/1203.6881v1
Arxiv.org
by M. De Angelis
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An equivalence between an integro-differential operator M and an evolution operator Ln is determined. From this equivalence the fundamental solution of Ln is estimated in terms of the fundamental solution related to the third-order operator L1 whose behavior is now available. Moreover, properties typical of wave hierarchies can be applied to polymeric materials. As an example the case n= 2 is considered and results are applied to the Rouse model and the reptation model which describe different...
Source: http://arxiv.org/abs/1203.0472v1
Arxiv.org
by D. Wilms; P. Virnau; S. Sengupta; K. Binder
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Langevin Dynamics simulations are used to study the effect of shear on a two-dimensional colloidal crystal confined by structured parallel walls. When walls are sheared very slowly, only two or three crystalline layers next to the walls move along with them, while the inner layers of the crystal are only slightly tilted. At higher shear velocities, this inner part of the crystal breaks into several pieces with different orientations. The velocity profile across the slit is reminiscent of...
Source: http://arxiv.org/abs/1203.3669v1
Deb Cotton Secondline Collection
by BigRedCotton
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favorite footwork artist LBJ Shalanda Goffner Source: https://www.youtube.com/watch?v=-GnWujs6ePI Uploader: BigRedCotton Upload date: 20120413
Topics: Youtube, video, Music, Shalanda Goffner, New Orleans, Second line, debcotton,...
Arxiv.org
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Recently, it has been shown that a quantize-map-and-forward scheme approximately achieves (within a constant number of bits) the Gaussian relay network capacity for arbitrary topologies. This was established using Gaussian codebooks for transmission and random mappings at the relays. In this paper, we show that the same approximation result can be established by using lattices for transmission and quantization along with structured mappings at the relays.
Source: http://arxiv.org/abs/1005.1284v2
Arxiv.org
by Mehdi Talamali; Viljo Petäjä; Damien Vandembroucq; Stéphane Roux
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A mesoscopic model for shear plasticity of amorphous materials in two dimensions is introduced, and studied through numerical simulations in order to elucidate the macroscopic (large scale) mechanical behavior. Plastic deformation is assumed to occur through a series of local reorganizations. Using a discretization of the mechanical fields on a discrete lattice, local reorganizations are modeled as local slip events. Local yield stresses are randomly distributed in space and invariant in time....
Source: http://arxiv.org/abs/1005.2463v3
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by A. Hill; A. Sinner; K. Ziegler
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We calculate the optical Hall conductivity within the Kubo formalism for systems with gapped spectral nodes, where the latter have a power-law dispersion with exponent n. The optical conductivity is proportional to n and there is a characteristic logarithmic singularity as the frequency approaches the gap energy. The optical Hall conductivity is almost unaffected by thermal fluctuations and disorder for n=1, whereas disorder has a stronger effect on transport properties if n=2.
Source: http://arxiv.org/abs/1005.3211v3
For a semi-abelian variety over a global function field which is isogenous to an isotrivial one, we show that on the product of local points of a subvariety satisfying a minor condition, the topological closure of a finitely generated subgroup of %the group of its global points cuts out exactly the global points of the subvariety lying in this subgroup. As a corollary, on every non-isotrivial super-singular curve of genus two over a global function field, we conclude that the Brauer-Manin...
Source: http://arxiv.org/abs/1005.4998v3
Arxiv.org
by Mark Adler; Eric Nordenstam; Pierre van Moerbeke
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In 1962, Dyson introduced dynamics in random matrix models, in particular into GUE (also for beta=1 and 4), by letting the entries evolve according to independent Ornstein-Uhlenbeck processes. Dyson shows the spectral points of the matrix evolve according to non-intersecting Brownian motions. The present paper shows that the interlacing spectra of two consecutive principal minors form a Markov process (diffusion) as well. This diffusion consists of two sets of Dyson non-intersecting Brownian...
Source: http://arxiv.org/abs/1007.0220v3
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We study some properties of the Venereau polynomials b_m=y+x^m(xz+y(yu+z^2)), a sequence of proposed counterexamples to the Abhyankar-Sathaye embedding conjecture and the Dolgachev-Weisfeiler conjecture. It is well known that these are hyperplanes and residual coordinates, and for m at least 3, they are C[x]-coordinates. For m=1,2, it is only known that they are 1-stable C[x]-coordinates. We show that b_2 is in fact a C[x]-coordinate. We introduce the notion of Venereau-type polynomials, and...
Source: http://arxiv.org/abs/1007.2230v3
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Let $H$ be a locally compact group, $K$ be an LCA group, $\tau:H\to Aut(K)$ be a continuous homomorphism and $G_\tau=H\ltimes_\tau K$ be the semi-direct product of $H$ and $K$ with respect to the continuous homomorphism $\tau$. In this article we introduce the $\tau\times\hat{\tau}$-time frequency group $G_{\tau\times\hat{\tau}}$. We define the $\tau\times\hat{\tau}$-continuous Gabor transform of $f\in L^2(G_\tau)$ with respect to a window function $u\in L^2(K)$ as a function defined on...
Source: http://arxiv.org/abs/1203.1517v1
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by M. Lapert; J. Salomon; D. Sugny
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We present a new formulation of monotonically convergent algorithms which allows to optimize both the control duration and the field fluence. A standard algorithm designs a control field of fixed duration which both brings the system close to the target state and minimizes its fluence, whereas here we include in addition the optimization of the duration in the cost functional. We apply this new algorithm to the control of spin systems in Nuclear Magnetic Resonance. We show how to implement CNOT...
Source: http://arxiv.org/abs/1203.2337v1
Arxiv.org
by Meera Sitharam; Aysegul Ozkan; James Pence; Jorg Peters
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To elucidate the structure of assembly configuration spaces, the EASAL software combines classical concepts, such as stratifications of semialgebraic sets, with recent algorithms for efficiently realizing geometric constraint systems, and theoretical advances concerning convex parametrization: in contrast to folding configuration spaces, most regions of assembly and packing configurations admit a convex parametrization. This allows for a novel, efficient and intuitive representation of...
Source: http://arxiv.org/abs/1203.3811v1
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by Francis Bach; Simon Lacoste-Julien; Guillaume Obozinski
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We show that the herding procedure of Welling (2009) takes exactly the form of a standard convex optimization algorithm--namely a conditional gradient algorithm minimizing a quadratic moment discrepancy. This link enables us to invoke convergence results from convex optimization and to consider faster alternatives for the task of approximating integrals in a reproducing kernel Hilbert space. We study the behavior of the different variants through numerical simulations. The experiments indicate...
Source: http://arxiv.org/abs/1203.4523v2
Arxiv.org
by Maria Rita Casali; Paola Cristofori; Michele Mulazzani
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The idea of computing Matveev complexity by using Heegaard decompositions has been recently developed by two different approaches: the first one for closed 3-manifolds via crystallization theory, yielding the notion of Gem-Matveev complexity; the other one for compact orientable 3-manifolds via generalized Heegaard diagrams, yielding the notion of modified Heegaard complexity. In this paper we extend to the non-orientable case the definition of modified Heegaard complexity and prove that for...
Source: http://arxiv.org/abs/1203.0183v1
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by M. Emin Ozdemir; Ahmet Ocak Akdemir; Mevlut Tunc
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In this paper, we establish some new inequalities of the Hermite-Hadamard like for class of (h-s)_{1,2}-convex functions which are ordinary, super-multiplicative or similarly ordered and nonnegative.
Source: http://arxiv.org/abs/1203.3698v1