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Dec 31, 2012
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Dec 31, 2012
by
Wicher Bergsma; Angelos Dassios

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The most popular ways to test for independence of two ordinal random variables are by means of Kendall's tau and Spearman's rho. However, such tests are not consistent, only having power for alternatives with `monotonic' association. In this paper we introduce a natural extension of Kendall's tau, called $\tau^*$, which is nonnegative and zero if and only if independence holds, thus leading to a consistent independence test. Furthermore, normalization gives a rank correlation which can be used...

Source: http://arxiv.org/abs/1007.4259v5

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Dec 31, 2012
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Dec 31, 2012
by
Jonathan W. Mason

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The theoretical base for consciousness, in particular an explanation of how consciousness is defined by the brain, has long been sought by science. We propose a partial theory of consciousness as relations defined by typical data. The theory is based on the idea that a brain state on its own is almost meaningless but in the context of the typical brain states, defined by the brain's structure, a particular brain state is highly structured by relations. The proposed theory can be applied and...

Source: http://arxiv.org/abs/1203.3113v2

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Dec 31, 2012
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Dec 31, 2012
by
Samuel Epstein; Leonid A. Levin

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The combined Universal Probability M(D) of strings x in sets D is close to max M({x}) over x in D: their ~logs differ by at most D's information j=I(D:H) about the halting sequence H. Thus if all x have complexity K(x) >k, D carries >i bits of information on each its x where i+j ~ k. Note that there are no ways to generate D with significant I(D:H).

Source: http://arxiv.org/abs/1107.1458v7

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Dec 30, 2012
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Dec 30, 2012
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Subhonmesh Bose; Dennice F. Gayme; K. Mani Chandy; Steven H. Low

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This paper proves that non-convex quadratically constrained quadratic programs can be solved in polynomial time when their underlying graph is acyclic, provided the constraints satisfy a certain technical condition. When this condition is not satisfied, we propose a heuristic to obtain a feasible point. We demonstrate this approach on optimal power flow problems over radial networks.

Source: http://arxiv.org/abs/1203.5599v2

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127

Dec 30, 2012
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Dec 30, 2012
by
Moritz Zaiss; Peter Bachert

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Chemical exchange observed by NMR saturation transfer (CEST) and spin-lock (SL) experiments provide an MRI contrast by indirect detection of exchanging protons. The determination of the relative concentrations and exchange rates is commonly achieved by numerical integration of the Bloch-McConnell equations. We derive an analytical solution of the Bloch-McConnell equations that describes the magnetization of coupled spin populations under radiofrequency irradiation.As CEST and off-resonant SL...

Source: http://arxiv.org/abs/1203.2067v2

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Dec 29, 2012
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Dec 29, 2012
by
V. P. Kirilin; Z. V. Khaidukov; A. V. Sadofyev

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In this note we consider non-relativistic rotating fermi liquid in the presence of Berry curvature. The behavior of the system is then almost the same as in external magnetic field. We argue that there appears an analogue of chiral vortical effect in the liquid if Berry curvature has a non-vanishing flux through sheets of Fermi surfaces and chemical potentials are different. We also claim that quantum anomalies in condensed matter context provide a theoretical and experimental testing ground...

Source: http://arxiv.org/abs/1203.6612v3

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Dec 29, 2012
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Dec 29, 2012
by
Sougata Pal; Simon Oechsner; Boris Bellalta; Miquel Oliver

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Interconnecting multiple sensor networks is a relatively new research field which has emerged in the Wireless Sensor Network domain. Wireless Sensor Networks (WSNs) have typically been seen as logically separate, and few works have considered interconnection and interaction between them. Interconnecting multiple heterogeneous sensor networks therefore opens up a new field besides more traditional research on, e.g., routing, self organization, or MAC layer development. Up to now, some approaches...

Source: http://arxiv.org/abs/1203.6316v2

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Dec 29, 2012
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Dec 29, 2012
by
Silvio Franz; Giorgio Parisi; Federico Ricci-Tersenghi

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We consider the critical properties of points of continuous glass transition as one can find in liquids in presence of constraints or in liquids in porous media. Through a one loop analysis we show that the critical Replica Field Theory describing these points can be mapped in the $\phi^4$-Random Field Ising Model. We confirm our analysis studying the finite size scaling of the $p$-spin model defined on sparse random graph, where a fraction of variables is frozen such that the phase transition...

Source: http://arxiv.org/abs/1203.4849v3

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Dec 28, 2012
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Dec 28, 2012
by
David Garcia Sanchez; Bruno Lacarrière; Marjorie Musy; Bernard Bourges

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Sensitivity analysis plays an important role in the understanding of complex models. It helps to identify influence of input parameters in relation to the outputs. It can be also a tool to understand the behavior of the model and then can help in its development stage. This study aims to analyze and illustrate the potential usefulness of combining first and second-order sensitivity analysis, applied to a building energy model (ESP-r). Through the example of a collective building, a sensitivity...

Source: http://arxiv.org/abs/1203.3055v2

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Dec 28, 2012
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Dec 28, 2012
by
C. E. A. Brett; K. F. Lam; K. J. H. Law; D. S. McCormick; M. R. Scott; A. M. Stuart

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Data assimilation methodologies are designed to incorporate noisy observations of a physical system into an underlying model in order to infer the properties of the state of the system. Filters refer to a class of data assimilation algorithms designed to update the estimation of the state as data is acquired sequentially. For linear problems subject to Gaussian noise filtering can be performed exactly using the Kalman filter. For nonlinear systems it can be approximated in a systematic way by...

Source: http://arxiv.org/abs/1203.5845v2

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Dec 28, 2012
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Dec 28, 2012
by
Sigbjørn Hervik; Marcello Ortaggio; Lode Wylleman

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We consider time reversal transformations to obtain twofold orthogonal splittings of any tensor on a Lorentzian space of arbitrary dimension n. Applied to the Weyl tensor of a spacetime, this leads to a definition of its electric and magnetic parts relative to an observer (i.e., a unit timelike vector field u), in any n. We study the cases where one of these parts vanishes in particular, i.e., purely electric (PE) or magnetic (PM) spacetimes. We generalize several results from four to higher...

Source: http://arxiv.org/abs/1203.3563v2

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Dec 27, 2012
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Dec 27, 2012
by
O-joung Kwon; Sang-il Oum

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We prove that every graph of rank-width $k$ is a pivot-minor of a graph of tree-width at most $2k$. We also prove that graphs of rank-width at most 1, equivalently distance-hereditary graphs, are exactly vertex-minors of trees, and graphs of linear rank-width at most 1 are precisely vertex-minors of paths. In addition, we show that bipartite graphs of rank-width at most 1 are exactly pivot-minors of trees and bipartite graphs of linear rank-width at most 1 are precisely pivot-minors of paths.

Source: http://arxiv.org/abs/1203.3606v2

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Dec 27, 2012
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Dec 27, 2012
by
Xinwen Zhu

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We prove the geometrical Satake isomorphism for a reductive group defined over F=k((t)), and split over a tamely ramified extension. As an application, we give a description of the nearby cycles on certain Shimura varieties via the Rapoport-Zink-Pappas local models.

Source: http://arxiv.org/abs/1107.5762v3

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Dec 27, 2012
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Dec 27, 2012
by
Piotr Niemiec

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A C*-algebra is n-homogeneous (where n is finite) if every its nonzero irreducible representation acts on an n-dimensional Hilbert space. An elementary proof of Fell's characterization of n-homogeneous C*-algebras (by means of their spectra) is presented. A spectral theorem and a functional calculus for finite systems of elements which generate n-homogeneous C*-algebras are proposed.

Source: http://arxiv.org/abs/1203.0857v2

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Dec 27, 2012
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Dec 27, 2012
by
Bakhodir Abdullaev; Axel Pelster

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The effect of a weak three-dimensional (3d) isotropic laser speckle disorder on various thermodynamic properties of a dilute Bose gas is considered at zero temperature. First, we summarize the derivation of the autocorrelation function of laser speckles in 1d and 2d following the seminal work of Goodman. The goal of this discussion is to show that a Gaussian approximation of this function, proposed in some recent papers, is inconsistent with the general background of laser speckle theory. Then...

Source: http://arxiv.org/abs/1203.1698v2

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Dec 27, 2012
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Dec 27, 2012
by
Adam Bzdak; Volker Koch; Vladimir Skokov

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We discuss the modification of the cumulants of the net baryon and net proton distributions due to the global conservation of baryon number in heavy-ion collisions. Corresponding probability distributions and their cumulants are derived analytically. We show that the conservation of baryon number results in a substantial decrease of higher order cumulants. Based on our studies, we propose an observable that is insensitive to the modifications due to baryon number conservation.

Source: http://arxiv.org/abs/1203.4529v2

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Dec 26, 2012
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Dec 26, 2012
by
Siddhartha Gadgil; Dheeraj Kulkarni

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We prove relative versions of the symplectic capping theorem and sufficiency of Giroux's criterion for Stein fillability and use these to study the 4-genus of knots.

Source: http://arxiv.org/abs/1203.4895v2

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Dec 26, 2012
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Dec 26, 2012
by
Yukie Sano; Kenta Yamada; Hayafumi Watanabe; Hideki Takayasu; Misako Takayasu

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To uncover underlying mechanism of collective human dynamics, we survey more than 1.8 billion blog entries and observe the statistical properties of word appearances. We focus on words that show dynamic growth and decay with a tendency to diverge on a certain day. After careful pretreatment and fitting method, we found power laws generally approximate the functional forms of growth and decay with various exponents values between -0.1 and -2.5. We also observe news words whose frequency increase...

Source: http://arxiv.org/abs/1107.4730v4

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Dec 26, 2012
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Dec 26, 2012
by
Zhicheng Hu; Keiwei Liang

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This paper studies the numerical solution of traveling singular sources problems. In such problems, a big challenge is the sources move with different speeds, which are described by some ordinary differential equations. A predictor-corrector algorithm is presented to simulate the position of singular sources. Then a moving mesh method in conjunction with domain decomposition is derived for the underlying PDE. According to the positions of the sources, the whole domain is splitted into several...

Source: http://arxiv.org/abs/1203.1826v2

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126

Dec 26, 2012
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Dec 26, 2012
by
Peter Anders; Philipp Werner; Matthias Troyer; Manfred Sigrist; Lode Pollet

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We calculate the phase diagram of the Bose-Fermi Hubbard model on the 3d cubic lattice at fermionic half filling and bosonic unit filling by means of single-site dynamical mean-field theory. For fast bosons, this is equivalent to the Cooper problem in which the bosons can induce s-wave pairing between the fermions. We also find miscible superfluid and canted supersolid phases depending on the interspecies coupling strength. In contrast, slow bosons favor fermionic charge density wave structures...

Source: http://arxiv.org/abs/1203.6359v2

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Dec 26, 2012
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Dec 26, 2012
by
Huan Yang; Zhenyu Wang; Delong Fang; Sheng Li; Toshikaze Kariyado; Genfu Chen; Masao Ogata; Tanmoy Das; A. V. Balatsky; Hai-Hu Wen

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We use spatially resolved scanning tunneling spectroscopy in Na(Fe{1-x}Cox)As to investigate the impurity effect induced by Co dopants. The Co impurities are successfully identified, and the spatial distributions of local density of state at different energies around these impurities are investigated. It is found that the spectrum shows negligible spatial variation at different positions near the Co impurity, although there is a continuum of the in-gap states which lifts the zero-bias...

Source: http://arxiv.org/abs/1203.3123v2

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38

Dec 24, 2012
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Dec 24, 2012
by
Hironobu Kihara

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Equations of motion of low-energy effective theories of quantum electrodynamics include infinitely many interaction terms, which make them difficult to solve. The self-duality property has facilitated research on the solutions to these equations. In this paper, equations of motion of systems of non-Abelian gauge fields on even-dimensional spheres are considered. It is demonstrated that the Cremmer-Scherk configuration, which satisfies certain generalized self-duality equations, becomes the...

Source: http://arxiv.org/abs/1203.1990v3

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Dec 24, 2012
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Dec 24, 2012
by
Paul Balmer; Baptiste Calmès

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We compute the total Witt groups of (split) Grassmann varieties, over any regular base X. The answer is a free module over the total Witt ring of X. We provide an explicit basis for this free module, which is indexed by a special class of Young diagrams, that we call even Young diagrams.

Source: http://arxiv.org/abs/0807.3296v3

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39

Dec 24, 2012
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Dec 24, 2012
by
Amnon Yekutieli

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We construct a 2-dimensional twisted nonabelian multiplicative integral. This is done in the context of a Lie crossed module (an object composed of two Lie groups interacting), and a pointed manifold. The integrand is a connection-curvature pair, that consists of a Lie algebra valued 1-form and a Lie algebra valued 2-form, satisfying a certain differential equation. The geometric cycle of the integration is a kite in the pointed manifold. A kite is made up of a 2-dimensional simplex in the...

Source: http://arxiv.org/abs/1007.1250v3

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31

Dec 24, 2012
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Dec 24, 2012
by
Andrei Ya. Maltsev

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In this paper we examine in detail the procedure of averaging of the local field-theoretic Poisson brackets proposed by B.A. Dubrovin and S.P. Novikov for the method of Whitham. The main attention is paid to the questions of justification and the conditions of applicability of the Dubrovin-Novikov procedure. Separate consideration is given to special features of single-phase and multiphase cases. In particular, one of the main results is the insensitivity of the procedure of bracket averaging...

Source: http://arxiv.org/abs/1203.5732v4

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108

Dec 23, 2012
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Dec 23, 2012
by
R. J. Crewther; Lewis C. Tunstall

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We replace ordinary chiral SU(3)_L * SU(3)_R perturbation theory CHPT_3 by a new theory CHPT_sigma based on a low-energy expansion about an infrared fixed point alpha_IR for 3-flavor QCD. At alpha_IR, the quark condensate _vac =\= 0 induces nine Nambu-Goldstone bosons: pi, K, eta and a 0++ QCD dilaton sigma. Physically, sigma appears as the f_0(500) resonance, a pole at a complex mass with real part < m_K. The \Delta I = 1/2 rule for nonleptonic K-decays is then a consequence of CHPT_sigma,...

Source: http://arxiv.org/abs/1203.1321v3

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Dec 23, 2012
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Dec 23, 2012
by
Victor Katsnelson

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A description of eigensubspaces of the cosine and sine operators is presented. The spectrum of each of these two operator consists of two eigenvalues (1,\,-1) and their eigensubspaces are infinite--dimensional. There are many possible bases for these subspaces, but most popular are bases constructed from the Hermite functions. We present other "bases" which are not discrete orthogonal sequences of vectors, but continuous orthogonal chains of vectors. Our work can be considered a...

Source: http://arxiv.org/abs/1203.2427v3

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Dec 22, 2012
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Dec 22, 2012
by
Anton Geraschenko; Matthew Satriano

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The purpose of this paper and its prequel (Toric Stacks I) is to introduce and develop a theory of toric stacks which encompasses and extends the notions of toric stacks defined in [Laf02, BCS05, FMN10, Iwa09, Sat12, Tyo12], as well as classical toric varieties. While the focus of the prequel is on how to work with toric stacks, the focus of this paper is how to show a stack is toric. For toric varieties, a classical result says that any normal variety with an action of a dense open torus...

Source: http://arxiv.org/abs/1107.1907v3

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204

Dec 22, 2012
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Dec 22, 2012
by
Anton Geraschenko; Matthew Satriano

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The purpose of this paper and its sequel (Toric Stacks II) is to introduce and develop a theory of toric stacks which encompasses and extends the notions of toric stacks defined in [Laf02, BCS05, FMN10, Iwa09, Sat12, Tyo12], as well as classical toric varieties. In this paper, we define a \emph{toric stack} as a quotient of a toric variety by a subgroup of its torus (we also define a generically stacky version). Any toric stack arises from a combinatorial gadget called a \emph{stacky fan}. We...

Source: http://arxiv.org/abs/1107.1906v3

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Dec 22, 2012
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Dec 22, 2012
by
Jan Heisig; Jörn Kersten

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We study the phenomenology of a supersymmetric scenario where the next-to-lightest superparticle is the lighter stau and long-lived due to a very weakly coupled lightest superparticle, such as the gravitino. We investigate the LHC sensitivity and its dependence on the superparticle spectrum with an emphasis on strong production and decay. We do not assume any high-scale model for SUSY breaking but work along the lines of simplified models. Devising cuts that yield a large detection efficiency...

Source: http://arxiv.org/abs/1203.1581v3

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108

Dec 22, 2012
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Dec 22, 2012
by
Ron A. Doney; Stavros Vakeroudis

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Using a generalization of the skew-product representation of planar Brownian motion and the analogue of Spitzer's celebrated asymptotic Theorem for stable processes due to Bertoin and Werner, for which we provide a new easy proof, we obtain some limit Theorems for the exit time from a cone of stable processes of index $\alpha\in(0,2)$. We also study the case $t\rightarrow0$ and we prove some Laws of the Iterated Logarithm (LIL) for the (well-defined) winding process associated to our planar...

Source: http://arxiv.org/abs/1203.3739v3

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Dec 21, 2012
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Dec 21, 2012

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107

Dec 21, 2012
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Dec 21, 2012
by
D. B. Espindola; M. C. Rodriguez; C. Brenner Mariotto

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This review starts out with a brief history of the photino-gluino phenomenology. Next, it describes difficulties encountered in the construction of Feynman amplitudes when dealing with Majorana fermions and outlines a procedure that circumvents this difficulty by means of a prescription based on a well-defined fermion flow without explicit charge-conjugation matrices at the vertex equations. Finally, as an illustration, it calculates the cross section for the production of photinos and gluinos.

Source: http://arxiv.org/abs/1107.5943v2

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Dec 21, 2012
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Dec 21, 2012
by
Tomas Kopf; Pavel Krtous; Don N. Page

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The observation that we are among the first 10^{11} or so humans reduces the prior probability that we find ourselves in a species whose total lifetime number of individuals is much higher, according to arguments of Carter, Leslie, Nielsen, and Gott. However, if we instead start with a prior probability that a history has a total lifetime number which is very large, without assuming that we are in such a history, this more basic probability is not reduced by the observation of how early in...

Source: http://arxiv.org/abs/gr-qc/9407002v2

One in a series of podcasts from Shrink Rap Radio, All the psychology you need to know and just enough to make you dangerous"

Topics: psychology, psychotherapy, counseling, counselor, therapist, psychotherapist, intuition, dreams,...

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77

Dec 21, 2012
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Dec 21, 2012
by
Hong Qian

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In complex systems, the interplay between nonlinear and stochastic dynamics, e.g., J. Monod's necessity and chance, gives rise to an evolutionary process in Darwinian sense, in terms of discrete jumps among attractors, with punctuated equilibrium, spontaneous random "mutations" and "adaptations". On an evlutionary time scale it produces sustainable diversity among individuals in a homogeneous population rather than convergence as usually predicted by a deterministic...

Source: http://arxiv.org/abs/1203.3554v2

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92

Dec 21, 2012
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Dec 21, 2012
by
Juan M. Romero; Eric Escobar; Etelberto Vazquez

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The action for a $(3+1)$-dimensional particle in very special relativity is studied. It is proved that massless particles only travel in effective $(2+1)$-dimensional space-time. It is remarkable that this action can be written as an action for a relativistic particle in a background gauge field and it is shown that this field causes the dimensional reduction. A new symmetry for this system is found. Furthermore, a general action with restored Lorentz symmetry is proposed for this system. It is...

Source: http://arxiv.org/abs/1203.2642v2

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62

Dec 20, 2012
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Dec 20, 2012
by
Yutao ma; Ran Wang; Liming Wu

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Consider the stochastic differential equation in $\rr^d$ dX^{\e}_t&=b(X^{\e}_t)dt+\sqrt{\e}\sigma(X^\e_t)dB_t X^{\e}_0&=x_0,\quad x_0\in\rr^d where $b:\rr^d\rightarrow\rr^d$ is $C^1$ such that $ \leq C(1+|x|^2)$, $\sigma:\rr^d\rightarrow \MM(d\times n)$ is locally Lipschitzian with linear growth, and $B_t$ is a standard Brownian motion taking values in $\rr^n$. Freidlin-Wentzell's theorem gives the large deviation principle for $X^\e$ for small $\e$. In this paper we establish its...

Source: http://arxiv.org/abs/1107.3432v2

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87

Dec 20, 2012
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Dec 20, 2012
by
Lillian B. Pierce

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We consider discrete analogues of fractional Radon transforms involving integration over paraboloids defined by positive definite quadratic forms. We prove that such discrete operators extend to bounded operators from $\ell^p$ to $\ell^q$ for a certain family of kernels. The method involves an intricate spectral decomposition according to major and minor arcs, motivated by ideas from the circle method of Hardy and Littlewood. Techniques from harmonic analysis, in particular Fourier transform...

Source: http://arxiv.org/abs/1005.4049v2

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96

Dec 20, 2012
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Dec 20, 2012
by
A. A. Deriglazov

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We construct a non-Grassmann spinning-particle model which, by analogy with quantum mechanics, does not admit the notion of a trajectory within the position space. The pseudo-classical character of the model allows us to avoid the inconsistencies arising in the quantum-mechanical interpretation of a one-particle sector of the Dirac equation.

Source: http://arxiv.org/abs/1203.5697v3

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57

Dec 20, 2012
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Dec 20, 2012
by
D0 Collaboration

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We present measurements of the differential cross section dsigma/dpT_gamma for the inclusive production of a photon in association with a b-quark jet for photons with rapidities |y_gamma| < 1.0 and 3015 GeV and rapidity |y_jet| < 1.5. The results are based on data corresponding to an integrated luminosity of 8.7 fb^-1, recorded with the D0 detector at the Fermilab Tevatron $p\bar{p}$ Collider at sqrt(s)=1.96 TeV. The measured cross sections are compared with next-to-leading order...

Source: http://arxiv.org/abs/1203.5865v2

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52

Dec 20, 2012
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Dec 20, 2012
by
Francis Comets; Michael Cranston

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We consider large time behavior of typical paths under the Anderson polymer measure. If $P$ is the measure induced by rate $\kappa,$ simple, symmetric random walk on $Z^d$ started at $x,$ this measure is defined as $$ d\mu(X)={Z^{-1} \exp\{\beta\int_0^T dW_{X(s)}(s)\}dP(X) $$ where $\{W_x:x\in Z^d\}$ is a field of $iid$ standard, one-dimensional Brownian motions, $\beta>0, \kappa>0$ and $Z$ the normalizing constant. We establish that the polymer measure gives a macroscopic mass to a small...

Source: http://arxiv.org/abs/1107.2011v3

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Dec 20, 2012
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Dec 20, 2012
by
A. Mezio; L. O. Manuel; R. R. P. Singh; A. E. Trumper

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We study the low temperature properties of the triangular-lattice Heisenberg antiferromagnet with a mean field Schwinger spin-1/2 boson scheme that reproduces quantitatively the zero temperature energy spectrum derived previously using series expansions. By analyzing the spin-spin and the boson density-density dynamical structure factors, we identify the unphysical spin excitations that come from the relaxation of the local constraint on bosons. This allows us to reconstruct a free energy based...

Source: http://arxiv.org/abs/1203.3794v2

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48

Dec 19, 2012
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Dec 19, 2012
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

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Dec 19, 2012
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Dec 19, 2012
by
Raju Baddi

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A very simple low cost bipolar transistor tester for physics lab is given. The proposed circuit not only indicates the type of transistor(NPN/PNP) but also indicates the terminals(emitter, base and collector) using simple dual color (red/green) LEDs. Color diagrams of testing procedure have been given for easy following. This article describes the construction of this apparatus in all detail with schematic circuit diagram, circuit layout and constructional illustration. The second part...

Source: http://arxiv.org/abs/1203.2861v2

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485

Dec 19, 2012
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Dec 19, 2012
by
Tsogtgerel Gantumur

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This paper presents adaptive boundary element methods for positive, negative, as well as zero order operator equations, together with proofs that they converge at certain rates. The convergence rates are quasi-optimal in a certain sense under mild assumptions that are analogous to what is typically assumed in the theory of adaptive finite element methods. In particular, no saturation-type assumption is used. The main ingredients of the proof that constitute new findings are some results on a...

Source: http://arxiv.org/abs/1107.0524v4

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Dec 19, 2012
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Dec 19, 2012
by
Stephan Fackler

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An interesting result by T. Kato and A. Pazy says that a contractive semigroup (T(t)) on a uniformly convex space X is holomorphic iff limsup_{t \downarrow 0} ||T(t)-Id|| < 2. We study extensions of this result which are valid on arbitrary Banach spaces for semigroups which are not necessarily contractive. This allows us to prove a general extrapolation result for holomorphy of semigroups on interpolation spaces of exponent {\theta} in (0,1). As application we characterize boundedness of the...

Source: http://arxiv.org/abs/1203.5498v3

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Dec 19, 2012
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Dec 19, 2012
by
Sebastian Casalaina-Martin; Jesse Leo Kass; Filippo Viviani

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This paper studies the local geometry of compactified Jacobians constructed by Caporaso, Oda-Seshadri, Pandharipande, and Simpson. The main result is a presentation of the completed local ring of the compactified Jacobian of a nodal curve as an explicit ring of invariants described in terms of the dual graph of the curve. The authors have investigated the geometric and combinatorial properties of these rings in previous work, and consequences for compactified Jacobians are presented in this...

Source: http://arxiv.org/abs/1107.4166v2

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Dec 18, 2012
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Dec 18, 2012
by
Silvere Bonnabel; Anne Collard; Rodolphe Sepulchre

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The generalization of the geometric mean of positive scalars to positive definite matrices has attracted considerable attention since the seminal work of Ando. The paper generalizes this framework of matrix means by proposing the definition of a rank-preserving mean for two or an arbitrary number of positive semi-definite matrices of fixed rank. The proposed mean is shown to be geometric in that it satisfies all the expected properties of a rank-preserving geometric mean. The work is motivated...

Source: http://arxiv.org/abs/1007.5494v3

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Dec 18, 2012
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Dec 18, 2012
by
Ali Mostafazadeh

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We extend the formulation of pseudo-Hermitian quantum mechanics to eta-pseudo-Hermitian Hamiltonian operators H with an unbounded metric operator eta. In particular, we give the details of the construction of the physical Hilbert space, observables, and equivalent Hermitian Hamiltonian for the case that H has a real and discrete spectrum and its eigenvectors belong to the domain of eta and consequently its positive square root.

Source: http://arxiv.org/abs/1203.6241v5

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Dec 18, 2012
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Dec 18, 2012
by
Nematollah Riazi; Marzieh Peyravi

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In this paper, we obtain stable and metastable soliton solutions of a coupled system of two real scalar fields with five five discrete points of vacua. These solutions have definite topological charges and rest energies and show classical dynamical stability. From a quantum point of view, however, the V-type solutions are expected to be unstable and decay to D-type solutions. The induced decay of a V-type soliton into two D-type ones is calculated numerically, and shown to be chiral, in the...

Source: http://arxiv.org/abs/1107.3361v3

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Dec 18, 2012
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Dec 18, 2012
by
Alan Demlow; Anil N. Hirani

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Finite element exterior calculus (FEEC) has been developed over the past decade as a framework for constructing and analyzing stable and accurate numerical methods for partial differential equations by employing differential complexes. The recent work of Arnold, Falk and Winther \cite{ArFaWi2010} includes a well-developed theory of finite element methods for Hodge Laplace problems, including a priori error estimates. In this work we focus on developing a posteriori error estimates in which the...

Source: http://arxiv.org/abs/1203.0803v3

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Dec 18, 2012
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Dec 18, 2012
by
Sergey Ivashkovich

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We prove a certain non-linear version of the Levi extension theorem for meromorphic functions. This means that the meromorphic function in question is supposed to be extendable along a sequence of complex curves, which are arbitrary, not necessarily straight lines. Moreover, these curves are not supposed to belong to any finite dimensional analytic family. The conclusion of our theorem is that nevertheless the function in question meromorphically extends along an (infinite dimensional) analytic...

Source: http://arxiv.org/abs/1203.1433v2

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Dec 18, 2012
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Dec 18, 2012
by
Anupam Das; Nikita Borisov

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Anonymous communication systems are subject to selective denial-of-service (DoS) attacks. Selective DoS attacks lower anonymity as they force paths to be rebuilt multiple times to ensure delivery which increases the opportunity for more attack. In this paper we present a detection algorithm that filters out compromised communication channels for one of the most widely used anonymity networks, Tor. Our detection algorithm uses two levels of probing to filter out potentially compromised tunnels....

Source: http://arxiv.org/abs/1107.3863v3

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Dec 18, 2012
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Dec 18, 2012
by
Lorenzo Hernández; Jorge Tejero; Alberto Suárez; Santiago Carrillo-Menéndez

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A perturbative approach is used to derive approximations of arbitrary order to estimate high percentiles of sums of positive independent random variables that exhibit heavy tails. Closed-form expressions for the successive approximations are obtained both when the number of terms in the sum is deterministic and when it is random. The zeroth order approximation is the percentile of the maximum term in the sum. Higher orders in the perturbative series involve the right-truncated moments of the...

Source: http://arxiv.org/abs/1203.2564v3

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Dec 17, 2012
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Dec 17, 2012
by
Asher, Michael

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A great read-to-and-discuss book and a fun accessible reader for children from five years up. Author's and illustrator's royalties all go to the Trust for African Schools.

Topics: cando media, Africa

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Dec 17, 2012
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Dec 17, 2012
by
Marco Andreatta

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Let (X,L) be a quasi polarized pairs, i.e. X is a normal complex projective variety and L is a nef and big line bundle on it. We study, up to birational equivalence, the positivity (nefness) of the adjoint bundles K_X + rL for high rational number r. For this we run a Minimal Model Program with scaling relative to the divisor K_X +rL. We give some applications, namely the classification up to birational equivalence of quasi polarized pairs with sectional genus 0,1 and of embedded projective...

Source: http://arxiv.org/abs/1107.4878v2

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Dec 17, 2012
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Dec 17, 2012
by
Keegans, Janet; Matsaert, Harriet

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An amusing story with charming illustrations which retells with a twist the Nguni creation legend about why the giraffe has such a long neck. The little giraffe in this book is a very inquisitive character determined to find out everyone's secrets. His curiosity leads him right across Africa with only a faithful oxpecker for company. Giraffe's thirst for knowledge brings unexpected results--whether for better or worse depends on your point of view.

Topics: cando media, Africa

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Dec 17, 2012
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Dec 17, 2012
by
Victor Batyrev; Anne Moreau

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For arbitrary connected reductive group G we consider the motivic integral over the arc space of an arbitrary Q-Gorenstein horospherical G-variety associated with a colored fan and prove a formula for the stringy E-function of a horospherical variety X which generalizes the one for toric varieties. We remark that in contrast to toric varieties the stringy E-function of a Gorenstein horospherical variety X may be not a polynomial if some cones in the fan of X have nonempty sets of colors. Using...

Source: http://arxiv.org/abs/1203.0671v2

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Dec 17, 2012
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Dec 17, 2012
by
Yuri I. Manin; Matilde Marcolli

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The set of all error--correcting block codes over a fixed alphabet with $q$ letters determines a recursively enumerable set of rational points in the unit square with coordinates $(R,\delta)$:= (relative transmission rate, relative minimal distance). Limit points of this set form a closed subset, defined by $R\le \alpha_q(\delta)$, where $\alpha_q(\delta)$ is a continuous decreasing function called asymptotic bound. Its existence was proved by the first--named author in 1981 ([Man1]), but no...

Source: http://arxiv.org/abs/1203.0653v2

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Dec 17, 2012
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Dec 17, 2012
by
Johannes Schmidt-Hieber; Axel Munk; Lutz Duembgen

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We derive multiscale statistics for deconvolution in order to detect qualitative features of the unknown density. An important example covered within this framework is to test for local monotonicity on all scales simultaneously. We investigate the moderately ill-posed setting, where the Fourier transform of the error density in the deconvolution model is of polynomial decay. For multiscale testing, we consider a calibration, motivated by the modulus of continuity of Brownian motion. We...

Source: http://arxiv.org/abs/1107.1404v3

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Dec 17, 2012
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Dec 17, 2012
by
Hurd, David

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In his memoir David Hurd tells us of his adventures in Kenya in the 1960s and 1970s. His travels and work in the coast lead him to many adventures from kidnappings to wild encounters with animals and even ghosts. Hurd becomes a fisherman and settles on what his friends christen "Robinson Island". He later builds a restaurant on it and goes through tough experiences to ensure its success. It is a story of a man in search of new beginnings and his willingness to try anything the great...

Topics: cando media, Africa

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Dec 17, 2012
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Dec 17, 2012
by
Paolo Muratore-Ginanneschi; Carlos Mejía-Monasterio; Luca Peliti

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We derive the equations governing the protocols minimizing the heat released by a continuous-time Markov jump process on a one-dimensional countable state space during a transition between assigned initial and final probability distributions in a finite time horizon. In particular, we identify the hypotheses on the transition rates under which the optimal control strategy and the probability distribution of the Markov jump problem obey a system of differential equations of...

Source: http://arxiv.org/abs/1203.4062v2

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Dec 17, 2012
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Dec 17, 2012
by
Fabio Tanturri

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Let K be a field of characteristic zero. We describe an algorithm which requires a homogeneous polynomial F of degree three in K[x_0,x_1,x_2,x_3] and a zero A of F in P^3_K and ensures a linear pfaffian representation of V(F) with entries in K[x_0,x_1,x_2,x_3], under mild assumptions on F and A. We use this result to give an explicit construction of (and to prove the existence of) a linear pfaffian representation of V(F), with entries in K'[x_0,x_1,x_2,x_3], being K' an algebraic extension of K...

Source: http://arxiv.org/abs/1203.0999v2

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Dec 17, 2012
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Dec 17, 2012
by
Yuri I. Manin; Maxim Smirnov

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We explicitly calculate some Gromov--Witten correspondences determined by maps of labeled curves of genus zero to the moduli spaces of labeled curves of genus zero. We consider these calculations as the first step towards studying the self--referential nature of motivic quantum cohomology.

Source: http://arxiv.org/abs/1107.4915v2

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Dec 17, 2012
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Dec 17, 2012
by
Asher, Michael

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A Desert Dies chronicles Michael Asher's life with desert communities in the Sahara over three drought-filled years. While Michael came to appreciate the allure of a nomadic life in isolation he also saw how the perennial failure of rains devastated the way of life of even the hardiest of residents.

Topics: cando media, Africa

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41

Dec 17, 2012
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Dec 17, 2012
by
Weixiao Shen

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We study the expanding properties of random perturbations of regular interval maps satisfying the summability condition of exponent one. Under very general conditions on the interval maps and perturbation types, we prove strong stochastic stability.

Source: http://arxiv.org/abs/1107.2537v3

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Dec 17, 2012
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Dec 17, 2012
by
Keshavjee, Shariffa; Allela, Melisa

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Momo Makes a Mess is the second book in a series of illustrated children's books about the rescue of a monkey and how his presence livens up the household of two children a boy and a girl. In this book Geno and Alid give Momo a bath and learn a little more about the challenges of looking after a monkey. They also learn how just how mischievous a little monkey can be and how much they have to clean up after him. The adventures of Momo are based on a true story.

Topics: cando media, Africa

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90

Dec 16, 2012
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Dec 16, 2012
by
Ronen Eldan

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We consider the isoperimetric inequality on the class of high-dimensional isotropic convex bodies. We establish quantitative connections between two well-known open problems related to this inequality, namely, the thin shell conjecture, and the conjecture by Kannan, Lovasz, and Simonovits, showing that the corresponding optimal bounds are equivalent up to logarithmic factors. In particular we prove that, up to logarithmic factors, the minimal possible ratio between surface area and volume is...

Source: http://arxiv.org/abs/1203.0893v5

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Dec 16, 2012
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Dec 16, 2012
by
Benoît Noyelles

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This note tackles the problem of the rotation of Io with the 4-degrees of freedom Poincar\'e-Hough model. Io is modeled as a 2-layer body, i.e. a triaxial fluid core and a rigid outer layer. We show that the longitudinal librations should have an amplitude of about 30 arcseconds, independent of the composition of the core. We also estimate the tidal instability of the core, and show that should be slowly unstable.

Source: http://arxiv.org/abs/1203.3867v2

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Dec 16, 2012
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Dec 16, 2012
by
Dang Hop Nguyen

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Toric face rings is a generalization of the concepts of affine monoid rings and Stanley-Reisner rings. We consider several properties which imply Koszulness for toric face rings over a field $k$. Generalizing works of Laudal, Sletsj\o{}e and Herzog et al., graded Betti numbers of $k$ over the toric face rings are computed, and a characterization of Koszul toric face rings is provided. We investigate a conjecture suggested by R\"{o}mer about the sufficient condition for the Koszul property....

Source: http://arxiv.org/abs/1107.4503v3

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Dec 15, 2012
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Dec 15, 2012
by
Kavan Modi; César A. Rodríguez-Rosario; Alán Aspuru-Guzik

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The constraints imposed by the initial system-environment correlation can lead to nonpositive Dynamical maps. We find the conditions for positivity and complete positivity of such dynamical maps by using the concept of an assignment map. Any initial system-environment correlations make the assignment map nonpositive, while the positivity of the dynamical map depends on the interplay between the assignment map and the system-environment coupling. We show how this interplay can reveal or hide the...

Source: http://arxiv.org/abs/1203.5209v2

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177

Dec 15, 2012
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Dec 15, 2012
by
M. V. Gorbatenko; V. P. Neznamov

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We have proposed previously a method for constructing self-conjugate Hamiltonians H_eta in the eta-representation with a flat scalar product to describe the dynamics of Dirac particles in arbitrary gravitational fields. In this paper, we prove that, for block-diagonal metrics, the Hamiltonians H_eta can be obtained, in particular, using "reduced" parts of Dirac Hamiltonians, i.e. expressions for Dirac Hamiltonians derived using tetrad vectors in the Schwinger gauge without or with a...

Source: http://arxiv.org/abs/1107.0844v6

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88

Dec 15, 2012
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Dec 15, 2012
by
Hiroaki Ishida; Yael Karshon

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We show that if a holomorphic $n$ dimensional compact torus action on a compact connected complex manifold of complex dimension $n$ has a fixed point then the manifold is equivariantly biholomorphic to a smooth toric variety.

Source: http://arxiv.org/abs/1203.0789v3

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81

Dec 14, 2012
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Dec 14, 2012
by
F. Vega Reyes; A. Santos; V. Garzó

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We study in this work steady laminar flows in a low density granular gas modelled as a system of identical smooth hard spheres that collide inelastically. The system is excited by shear and temperature sources at the boundaries, which consist of two infinite parallel walls. Thus, the geometry of the system is the same that yields the planar Fourier and Couette flows in standard gases. We show that it is possible to describe the steady granular flows in this system, even at large inelasticities,...

Source: http://arxiv.org/abs/1203.0266v2

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Dec 14, 2012
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Dec 14, 2012
by
Francescopaolo Montefalcone

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We prove some stability results for smooth H-minimal hypersurfaces immersed in a sub-Riemannian k-step Carnot group G. The main tools are the formulas for the 1st and 2nd variation of the H-perimeter measure.

Source: http://arxiv.org/abs/1203.5972v4

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50

Dec 14, 2012
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Dec 14, 2012
by
J. Feilhauer; M. Mosko

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Typical persistent current ($I_{typ}$) in a normal metal ring with disorder due to random grain boundaries and rough edges is calculated microscopically. If disorder is due to the rough edges, a ballistic current $I_{typ}\simeq e v_F/L$ is found in spite of the diffusive resistance ($ \propto L/l$), where $v_F$ is the Fermi velocity, $l$ is the mean free path, and $L \gg l$ is the ring length. This ballistic current has a simple interpretation: It is due to a single coherent electron that moves...

Source: http://arxiv.org/abs/1203.6512v3

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120

Dec 14, 2012
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Dec 14, 2012
by
Hoeskuldur P. Halldorsson

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We give a classification of all self-similar solutions to the curve shortening flow in the plane.

Source: http://arxiv.org/abs/1007.1617v2

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109

Dec 14, 2012
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Dec 14, 2012
by
Tobias Schmidt

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Let L be a p-adic local field and g a finite dimensional Lie algebra over L. We show that its hyperenveloping algebra F(g) is a stably flat completion of its universal enveloping algebra. As a consequence the relative cohomology for the locally convex algebra F(g) coincides with the underlying Lie algebra cohomology. Final version. Some minor items corrected. Appeared in Journal of Algebra (2010).

Source: http://arxiv.org/abs/0807.2847v2

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121

Dec 14, 2012
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Dec 14, 2012
by
Matthew Ballard; David Favero; Ludmil Katzarkov

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We study the relationship between derived categories of factorizations on gauged Landau-Ginzburg models related by variations of the linearization in Geometric Invariant Theory. Under assumptions on the variation, we show the derived categories are comparable by semi-orthogonal decompositions and describe the complementary components. We also verify a question posed by Kawamata: we show that $D$-equivalence and $K$-equivalence coincide for such variations. The results are applied to obtain a...

Source: http://arxiv.org/abs/1203.6643v3

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59

Dec 13, 2012
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Dec 13, 2012
by
Santtu Ruotsalainen

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Antilinear operators on a complex Hilbert space arise in various contexts in mathematical physics. In this paper, an analogue of the Weyl--von Neumann theorem for antilinear self-adjoint operators is proved, i.e. that an antilinear self-adjoint operator is the sum of a diagonalizable operator and of a compact operator with arbitrarily small Schatten $p$-norm. In doing so, we discuss conjugations and their properties. A spectral integral representation for antilinear self-adjoint operators is...

Source: http://arxiv.org/abs/1203.4670v2

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32

Dec 13, 2012
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Dec 13, 2012
by
Chiara Cinti; Stephane Menozzi; Sergio Polidoro

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We obtain two-sided bounds for the density of stochastic processes satisfying a weak H\"ormander condition. In particular we consider the cases when the support of the density is not the whole space and when the density has various asymptotic regimes depending on the starting/final points considered (which are as well related to the number of brackets needed to span the space in H\"ormander's theorem). The proofs of our lower bounds are based on Harnack inequalities for positive...

Source: http://arxiv.org/abs/1203.4918v2

One in a series of podcasts from Shrink Rap Radio, All the psychology you need to know and just enough to make you dangerous"

Topics: psychology, psychotherapy, counseling, counselor, therapist, psychotherapist, intuition, dreams,...

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131

Dec 13, 2012
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Dec 13, 2012
by
Jie Han; Yi Zhao

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Let $G$ be a $k$-partite graph with $n$ vertices in parts such that each vertex is adjacent to at least $\delta^*(G)$ vertices in each of the other parts. Magyar and Martin \cite{MaMa} proved that for $k=3$, if $\delta^*(G)\ge 2/3n $ and $n$ is sufficiently large, then $G$ contains a $K_3$-factor (a spanning subgraph consisting of $n$ vertex-disjoint copies of $K_3$) except that $G$ is one particular graph. Martin and Szemer\'edi \cite{MaSz} proved that $G$ contains a $K_4$-factor when...

Source: http://arxiv.org/abs/1203.2667v2

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198

Dec 13, 2012
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Dec 13, 2012
by
Shi-Mei Ma; Chak-On Chow

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In this paper, we focus on the enumeration of permutations by number of cyclic occurrence of peaks and valleys. We find several recurrence relations involving the number of permutations with a prescribed number of cyclic peaks, cyclic valleys, fixed points and cycles. Several associated permutation statistics and the corresponding generating functions are also studied. In particular, we establish a connection between cyclic valleys and Pell numbers as well as cyclic peaks and alternating runs.

Source: http://arxiv.org/abs/1203.6264v2

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77

Dec 13, 2012
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Dec 13, 2012
by
Francisco Delgado-Vences; Marta Sanz-Solé

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A characterization of the support in H\"older norm of the law of the solution for a stochastic wave equation with three-dimensional space variable is proved. The result is a consequence of an approximation theorem, in the convergence of probability, for a sequence of evolution equations driven by a family of regularizations of the driving noise.

Source: http://arxiv.org/abs/1203.1188v4

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46

Dec 13, 2012
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Dec 13, 2012
by
Eric Amar

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By a theorem of Andreotti and Grauert if $\omega $ is a $(p,q)$ current, $q < n,$ in a Stein manifold, $\bar \partial $ closed and with compact support, then there is a solution $u$ to $\bar \partial u=\omega $ still with compact support. The main result of this work is to show that if moreover $\omega \in L^{r}(dm),$ where $m$ is a suitable Lebesgue measure on the Stein manifold, then we have a solution $u$ with compact support {\sl and} in $L^{r}(dm).$ We prove it by estimates in $L^{r}$...

Source: http://arxiv.org/abs/1203.0759v5

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233

Dec 13, 2012
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Dec 13, 2012
by
Tillmann Jentsch; Andrei Moroianu; Uwe Semmelmann

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We describe extrinsic hyperspheres and totally geodesic hypersurfaces in manifolds with special holonomy. In particular we prove the nonexistence of extrinsic hyperspheres in quaternion-Kaehler manifolds. We develop a new approach to extrinsic hyperspheres based on the classification of special Killing forms.

Source: http://arxiv.org/abs/1107.1603v2

7th Ward Funk - original music by TBC Source: https://www.youtube.com/watch?v=r68_D8odrAc Uploader: BigRedCotton Upload date: 20121212

Topics: Youtube, video, Entertainment, Second line, brass band, parade, New Orleans, jazz, brass music,...

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49

Dec 12, 2012
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Dec 12, 2012
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

corner of Washington and LaSalle. Featuring Lady Buckjumpers Renata Hampton and Donzella Lamar on hype patrol Source: https://www.youtube.com/watch?v=7Di0DDiWIUY Uploader: BigRedCotton Upload date: 20121212

Topics: Youtube, video, Music, Second line, brass band, parade, New Orleans, jazz, brass music, live music...

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64

Dec 12, 2012
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Dec 12, 2012
by
Luis Dieulefait; Ariel Pacetti; Matthias Schuett

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We prove that the Consani-Scholten quintic, a Calabi-Yau threefold over QQ, is Hilbert modular. For this, we refine several techniques known from the context of modular forms. Most notably, we extend the Faltings-Serre-Livne method to induced four-dimensional Galois representations over QQ. We also need a Sturm bound for Hilbert modular forms; this is developed in an appendix by Jose Burgos Gil and the second author.

Source: http://arxiv.org/abs/1005.4523v3

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Dec 12, 2012
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Dec 12, 2012
by
Matthew C. B. Zaremsky

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Let F_{n+m} be the free group of rank n+m, with generators x_1,...,x_{n+m}. An automorphism \phi of F_{n+m} is called partially symmetric if for each 1 \le i \le m, \phi(x_i) is conjugate to x_j or x_j^{-1} for some 1 \le j \le m. Let \Sigma\Aut_n^m be the group of partially symmetric automorphisms. We prove that for any m \ge 0 the inclusion \Sigma\Aut_n^m \to \Sigma\Aut_{n+1}^m induces an isomorphism in rational homology for dimensions i satisfying n \ge (3(i+1)+m)/2, with a similar statement...

Source: http://arxiv.org/abs/1203.4845v4

Source: https://www.youtube.com/watch?v=Ppdw2LCuQVo Uploader: BigRedCotton Upload date: 20121212

Topics: Youtube, video, Music, Treme, Second line, brass band, parade, New Orleans, jazz, brass music, live...

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73

Dec 12, 2012
12/12

Dec 12, 2012
by
Yashar D. Hezaveh; Daniel P. Marrone; Gilbert P. Holder

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We address two selection effects that operate on samples of gravitationally lensed dusty galaxies identified in millimeter- and submillimeter-wavelength surveys. First, we point out the existence of a "size bias" in such samples: due to finite source effects, sources with higher observed fluxes are increasingly biased towards more compact objects. Second, we examine the effect of differential lensing in individual lens systems by modeling each source as a compact core embedded in an...

Source: http://arxiv.org/abs/1203.3267v2

featuring drummers from the Andrews family: cousins Glenn Finister Andrews, Jenard Andrews and Hassan Goffner. Glenn's father Glenn plays with the Rebirth Brass Band; Jenard's father is James '12' Andrews, 'Satchmo of the Ghetto'; Hassan's father is Trombone Shorty, his stepfather is TBC tuba player Brenard 'Bunny' Adams. The Andrews are a vast musical family from Treme. Source: https://www.youtube.com/watch?v=LECHmHqMfRE Uploader: BigRedCotton Upload date: 20121212

Topics: Youtube, video, Music, Second line, brass band, parade, New Orleans, jazz, brass music, live music...

at the Brothers of Change 2012 second line parade Source: https://www.youtube.com/watch?v=jM0qzOunCJU Uploader: BigRedCotton Upload date: 20121212

Topics: Youtube, video, Music, Second line, brass band, parade, New Orleans, jazz, brass music, live music...

TBC playing 'Shallow Water' Source: https://www.youtube.com/watch?v=kYItYLN0x0k Uploader: BigRedCotton Upload date: 20121212

Topics: Youtube, video, Music, Second line, brass band, parade, New Orleans, jazz, brass music, live music...

this was a one man parade. the clubs schedule with the city for police patrols and if you don't parade on your designated day, you stand losing it to another club - there are a lot of clubs on the waiting list to get their own parade day. So sometimes if a club can't parade because of money or some other reason, one member will parade anyway in order to keep the date. Source: https://www.youtube.com/watch?v=Zy1iwEchEsQ Uploader: BigRedCotton Upload date: 20121212

Topics: Youtube, video, Music, Second line, brass band, parade, New Orleans, jazz, brass music, live music...