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Arxiv.org
by Natalia B. Janson; Christopher J. Marsden
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We propose an alternative approach to construct an artificial learning system, which naturally learns in an unsupervised manner. Its mathematical prototype is a dynamical system, which automatically shapes its vector field in response to the input signal. The vector field converges to a gradient of a multi-dimensional probability density distribution of the input process, taken with negative sign. The most probable patterns are represented by the stable fixed points, whose basins of attraction...
Source: http://arxiv.org/abs/1107.0674v2
Arxiv.org
by Leandro M. Del Pezzo; Sandra Martinez
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In this paper we study the $H^2$ global regularity for solutions of the $p(x)-$Laplacian in two dimensional convex domains with Dirichlet boundary conditions. Here $p:\Omega \to [p_1,\infty)$ with $p\in Lip(\bar{\Omega})$ and $p_1>1$.
Source: http://arxiv.org/abs/1107.3136v2
In our previous work, we identify the Sublattice-Pairing State (SPS) in Schwinger-fermion representation as the spin liquid phase discovered in recent numerical study on a honeycomb lattice. In this paper, we show that SPS is identical to the zero-flux $Z_2$ spin liquid in Schwinger-boson representation found by Wang\cite{Wang2010} by an explicit duality transformation. SPS is connected to an \emph{unusual} antiferromagnetic ordered phase, which we term as chiral-antiferromagnetic (CAF) phase,...
Source: http://arxiv.org/abs/1007.3266v2
Arxiv.org
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Graphite oxide is an amorphous insulator. Although several models have been suggested, its structure remains controversial. To elucidate this issue, 5 samples were prepared by the Brodie process and the Staudenmaier process. The electronic structure of graphite oxide was examined with x-ray absorption near edge structure and the ratio of $sp^{2}$ to $sp^{3}$ bonded carbon atoms was investigated with x-ray photoemission spectroscopy as a function of sample preparation times. It was found that...
Source: http://arxiv.org/abs/1007.0287v2
Arxiv.org
by Ovidiu Savin; Enrico Valdinoci
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We discuss the $\Gamma$-convergence, under the appropriate scaling, of the energy functional $$ \|u\|_{H^s(\Omega)}^2+\int_\Omega W(u)dx,$$ with $s \in (0,1)$, where $\|u\|_{H^s(\Omega)}$ denotes the total contribution from $\Omega$ in the $H^s$ norm of $u$, and $W$ is a double-well potential. When $s\in [1/2,\,1)$, we show that the energy $\Gamma$-converges to the classical minimal surface functional -- while, when $s\in(0,\,1/2)$, it is easy to see that the functional $\Gamma$-converges to...
Source: http://arxiv.org/abs/1007.1725v3
Arxiv.org
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The strong coupling of rho meson to the nucleon produces $s$ and $p$ wave rho meson nucleon $(\rho N)$ resonances. In a nucleus, the $\rho N$ resonance-hole polarization generates the optical potential or self-energy for the rho meson. The scattering of rho meson due to this potential provides valuable informations about the $\rho N$ resonance dynamics in a nucleus. To investigate it, we use this potential to calculate the mass distribution spectrum for the $\rho$ meson produced coherently in...
Source: http://arxiv.org/abs/1005.0187v2
Arxiv.org
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In this paper we use formal asymptotic arguments to understand the stability proper- ties of equivariant solutions to the Landau-Lifshitz-Gilbert model for ferromagnets. We also analyze both the harmonic map heatflow and Schrodinger map flow limit cases. All asymptotic results are verified by detailed numerical experiments, as well as a robust topological argument. The key result of this paper is that blowup solutions to these problems are co-dimension one and hence both unstable and...
Source: http://arxiv.org/abs/1107.2620v1
Arxiv.org
by Laurent Bartholdi
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We show that contracting self-similar groups satisfy the Farrell-Jones conjectures as soon as their universal contracting cover is non-positively curved. This applies in particular to bounded self-similar groups. We define, along the way, a general notion of contraction for groups acting on a rooted tree in a not necessarily self-similar manner.
Source: http://arxiv.org/abs/1107.5339v2
Arxiv.org
by Jose A. de Azcarraga; Jose M. Izquierdo
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We use the expansion of superalgebras procedure (summarized in the text) to derive Chern-Simons (CS) actions for the (p,q)-Poincare supergravities in three-dimensional spacetime. After deriving the action for the (p,0)-Poincare supergravity as a CS theory for the expansion osp(p|2;R)(2,1) of osp(p|2;R), we find the general (p,q)-Poincare superalgebras and their associated D=3 supergravity actions as CS gauge theories from an expansion of the simple osp(p+q|2,R) superalgebras, namely...
Source: http://arxiv.org/abs/1107.2569v2
In this manuscript, the structure of broad emission line regions (BLRs) of well-mapping double-peaked emitter (AGN with broad double-peaked low-ionization emission lines) 3C390.3 is studied. Besides the best fitted results for double-peaked broad optical balmer lines of 3C390.3 by theoretical disk model, we try to find another way to further confirm the origination of double-peaked line from accretion disk. Based on the long-period observed spectra in optical band around 1995 collected from AGN...
Source: http://arxiv.org/abs/1107.0455v1
Arxiv.org
by Antonio E. Cárcamo Hernández; Riccardo Torre
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In the framework of a strong dynamics for Electro-Weak Symmetry Breaking (EWSB), both vector and scalar degrees of freedom have been studied in the literature within an effective Lagrangian approach. Here we consider the case in which both a scalar, $h$, and a vector, $V$ - respectively an iso-singlet and an iso-triplet under a custodial SU(2) - are relevant with a mass below the cut-off $\Lambda \approx 4\pi v$. We study the amplitudes for the processes $W_L W_L \to W_L W_L, hh, V_{L}V_{L},...
Source: http://arxiv.org/abs/1005.3809v3
Arxiv.org
by Taras Banakh; Magdalena Nowak
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Answering an old question of M.Hata, we construct an example of a 1-dimensional Peano continuum which is not homeomorphic to an attractor of IFS.
Source: http://arxiv.org/abs/1107.3804v1
Arxiv.org
by Warren R. Brown; Mukremin Kilic; J. J. Hermes; Carlos Allende Prieto; Scott J. Kenyon; D. E. Winget
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We have discovered a detached pair of white dwarfs (WDs) with a 12.75 min orbital period and a 1,315 km/s radial velocity amplitude. We measure the full orbital parameters of the system using its light curve, which shows ellipsoidal variations, Doppler boosting, and primary and secondary eclipses. The primary is a 0.25 Msun tidally distorted helium WD, only the second tidally distorted WD known. The unseen secondary is a 0.55 Msun carbon-oxygen WD. The two WDs will come into contact in 0.9 Myr...
Source: http://arxiv.org/abs/1107.2389v1
Arxiv.org
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For the description of the early inflation, and acceleration expansion of the Universe, compatible with observational data, the 5D noncompact Kaluza--Klein cosmology is investigated. It is proposed that the 5D space is filled with a null perfect fluid, resulting a perfect fluid in 4D universe, plus one along the fifth dimension. By analyzing the reduced field equations for flat FRW model, we show the early inflationary behavior and current acceleration of the universe.
Source: http://arxiv.org/abs/1005.3140v2
Arxiv.org
by Xi Chen; Simon P. Ellingsen; Zhi-Qiang Shen; Anita Titmarsh; Cong-Gui Gan
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We report the results of a systematic survey for 95 GHz class I methanol masers towards a new sample of 192 massive young stellar object (MYSO) candidates associated with ongoing outflows (known as extended green objects or EGOs) identified from the Spitzer GLIMPSE survey. The observations were made with the Australia Telescope National Facility (ATNF) Mopra 22-m radio telescope and resulted in the detection of 105 new 95 GHz class I methanol masers. For 92 of the sources our observations...
Source: http://arxiv.org/abs/1107.2914v1
Arxiv.org
by Sangjib Kim; Oded Yacobi
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The symplectic group branching algebra, B, is a graded algebra whose components encode the multiplicities of irreducible representations of Sp(2n-2,C) in each irreducible representation of Sp(2n,C). By describing on B an ASL structure, we construct an explicit standard monomial basis of B consisting of Sp(2n-2,C) highest weight vectors. Moreover, B is known to carry a canonical action of the n-fold product SL(2) \times ... \times SL(2), and we show that the standard monomial basis is the unique...
Source: http://arxiv.org/abs/1005.2320v2
Arxiv.org
by Yuriy Mishchencko; Joshua T. Vogelstein; Liam Paninski
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Deducing the structure of neural circuits is one of the central problems of modern neuroscience. Recently-introduced calcium fluorescent imaging methods permit experimentalists to observe network activity in large populations of neurons, but these techniques provide only indirect observations of neural spike trains, with limited time resolution and signal quality. In this work we present a Bayesian approach for inferring neural circuitry given this type of imaging data. We model the network...
Source: http://arxiv.org/abs/1107.4228v1
Arxiv.org
by Philipp Gubler; Makoto Oka
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QCD sum rules are analyzed with the help of the Maximum Entropy Method. We develop a new technique based on the Bayesion inference theory, which allows us to directly obtain the spectral function of a given correlator from the results of the operator product expansion given in the deep euclidean 4-momentum region. The most important advantage of this approach is that one does not have to make any a priori assumptions about the functional form of the spectral function, such as the "pole +...
Source: http://arxiv.org/abs/1005.2459v2
Arxiv.org
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We consider scheduling packets with values in a capacity-bounded buffer in an online setting. In this model, there is a buffer with limited capacity $B$. At any time, the buffer cannot accommodate more than $B$ packets. Packets arrive over time. Each packet is associated with a non-negative value. Packets leave the buffer only because they are either sent or dropped. Those packets that have left the buffer will not be reconsidered for delivery any more. In each time step, at most one packet in...
Source: http://arxiv.org/abs/1005.3835v3
Arxiv.org
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The Boltzmann collision operator for a dilute granular gas of inelastic rough hard spheres is much more intricate than its counterpart for inelastic smooth spheres. Now the one-body distribution function depends not only on the translational velocity of the center of mass but also on the angular velocity of the particle. Moreover, the collision rules couple both velocities, involving not only the coefficient of normal restitution but also the coefficient of tangential restitution. The aim of...
Source: http://arxiv.org/abs/1007.0700v2
Arxiv.org
by Walid Hachem; Malika Kharouf; Jamal Najim; Jack W. Silverstein
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In this article, we study the fluctuations of the random variable: $$ {\mathcal I}_n(\rho) = \frac 1N \log\det(\Sigma_n \Sigma_n^* + \rho I_N),\quad (\rho>0) $$ where $\Sigma_n= n^{-1/2} D_n^{1/2} X_n\tilde D_n^{1/2} +A_n$, as the dimensions of the matrices go to infinity at the same pace. Matrices $X_n$ and $A_n$ are respectively random and deterministic $N\times n$ matrices; matrices $D_n$ and $\tilde D_n$ are deterministic and diagonal, with respective dimensions $N\times N$ and $n\times...
Source: http://arxiv.org/abs/1107.0145v1
Arxiv.org
by Luc Simard; J. Trevor Mendel; David R. Patton; Sara L. Ellison; Alan W. McConnachie
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We perform two-dimensional, Point-Spread-Function-convolved, bulge+disk decompositions in the $g$ and $r$ bandpasses on a sample of 1,123,718 galaxies from the Legacy area of the Sloan Digital Sky Survey Data Release Seven. Four different decomposition procedures are investigated which make improvements to sky background determinations and object deblending over the standard SDSS procedures that lead to more robust structural parameters and integrated galaxy magnitudes and colors, especially in...
Source: http://arxiv.org/abs/1107.1518v1
Arxiv.org
by H. R. Jacobson; C. A. Pilachowski; E. D. Friel
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We present a detailed chemical abundance study of evolved stars in 10 open clusters based on Hydra multi-object echelle spectra obtained with the WIYN 3.5m telescope. From an analysis of both equivalent widths and spectrum synthesis, abundances have been determined for the elements Fe, Na, O, Mg, Si, Ca, Ti, Ni, Zr, and for two of the 10 clusters, Al and Cr. To our knowledge, this is the first detailed abundance analysis for clusters NGC 1245, NGC 2194, NGC 2355 and NGC 2425. These 10 clusters...
Source: http://arxiv.org/abs/1107.4139v1
Arxiv.org
by Joshua D. Simon; Marla Geha; Quinn E. Minor; Gregory D. Martinez; Evan N. Kirby; James S. Bullock; Manoj Kaplinghat; Louis E. Strigari; Beth Willman; Philip I. Choi; Erik J. Tollerud; Joe Wolf
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We present the results of a comprehensive Keck/DEIMOS spectroscopic survey of the ultra-faint Milky Way satellite galaxy Segue 1. We have obtained velocity measurements for 98.2% of the stars within 67 pc (10 arcmin, or 2.3 half-light radii) of the center of Segue 1 that have colors and magnitudes consistent with membership, down to a magnitude limit of r=21.7. Based on photometric, kinematic, and metallicity information, we identify 71 stars as probable Segue 1 members, including some as far...
Source: http://arxiv.org/abs/1007.4198v3
Arxiv.org
by R. A. Gutermuth; J. L. Pipher; S. T. Megeath; P. C. Myers; L. E. Allen; T. S. Allen
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We report the discovery and characterization of a power law correlation between the local surface densities of Spitzer-identified, dusty young stellar objects and the column density of gas (as traced by near-IR extinction) in eight molecular clouds within 1 kpc and with 100 or more known YSOs. This correlation, which appears in data smoothed over size scales of ~1 pc, varies in quality from cloud to cloud; those clouds with tight correlations, MonR2 and Ophiuchus, are fit with power laws of...
Source: http://arxiv.org/abs/1107.0966v1
Arxiv.org
by Sundar Vishwanathan
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We give a counting based proof of the Graham Pollak Theorem
Source: http://arxiv.org/abs/1007.1553v2
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by M. Ferrero; D. Salgado; J. L. Sanchez-Gomez
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It is argued that the traditional "realist" methodology of physics, according to which human concepts, laws and theories can grasp the essence of reality, is incompatible with the most fruitful interpretation of quantum formalism. The proof rests on the violation by quantum mechanics of the foundational principles of that methodology. An alternative methodology, in which the construction of sciences finishes at the level of human experience, as standard quantum theory strongly...
Source: http://arxiv.org/abs/1107.3366v1
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The bin packing problem is to find the minimum number of bins of size one to pack a list of items with sizes $a_1,..., a_n$ in $(0,1]$. Using uniform sampling, which selects a random element from the input list each time, we develop a randomized $O({n(\log n)(\log\log n)\over \sum_{i=1}^n a_i}+({1\over \epsilon})^{O({1\over\epsilon})})$ time $(1+\epsilon)$-approximation scheme for the bin packing problem. We show that every randomized algorithm with uniform random sampling needs $\Omega({n\over...
Source: http://arxiv.org/abs/1007.1260v3
Arxiv.org
by Y. Fukui; H. Sano; J. Sato; K. Torii; H. Horachi; T. Hayakawa; N. M. McClure-Griffiths; G. Rowell; T. Inoue; S. Inutsuka; A. Kawamura; H. Yamamoto; T. Okuda; N. Mizuno; T. Onishi; A. Mizuno; H. Ogawa
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RX J1713.7$-$3946 is the most remarkable TeV $\gamma$-ray SNR which emits $\gamma$-rays in the highest energy range. We made a new combined analysis of CO and \ion{H}{1} in the SNR and derived the total protons in the interstellar medium (ISM). We have found that the inclusion of the \ion{H}{1} gas provides a significantly better spatial match between the TeV $\gamma$-rays and ISM protons than the H$_2$ gas alone. In particular, the southeastern rim of the $\gamma$-ray shell has a counterpart...
Source: http://arxiv.org/abs/1107.0508v4
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This paper considers sparse linear discriminant analysis of high-dimensional data. In contrast to the existing methods which are based on separate estimation of the precision matrix $\O$ and the difference $\de$ of the mean vectors, we introduce a simple and effective classifier by estimating the product $\O\de$ directly through constrained $\ell_1$ minimization. The estimator can be implemented efficiently using linear programming and the resulting classifier is called the linear programming...
Source: http://arxiv.org/abs/1107.3442v1
Arxiv.org
by Ermin Wei; Asuman Ozdaglar; Ali Jadbabaie
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Most existing work uses dual decomposition and subgradient methods to solve Network Utility Maximization (NUM) problems in a distributed manner, which suffer from slow rate of convergence properties. This work develops an alternative distributed Newton-type fast converging algorithm for solving network utility maximization problems with self-concordant utility functions. By using novel matrix splitting techniques, both primal and dual updates for the Newton step can be computed using iterative...
Source: http://arxiv.org/abs/1005.2633v2
Arxiv.org
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We show that the three-dimensional layers-of-maxima problem can be solved in $o(n\log n)$ time in the word RAM model. Our algorithm runs in $O(n(\log \log n)^3)$ deterministic time or $O(n(\log\log n)^2)$ expected time and uses O(n) space. We also describe an algorithm that uses optimal O(n) space and solves the three-dimensional layers-of-maxima problem in $O(n\log n)$ time in the pointer machine model.
Source: http://arxiv.org/abs/1007.1593v2
Arxiv.org
by Necdet Serhat Aybat; Garud Iyengar
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We propose a first-order augmented Lagrangian algorithm (FAL) for solving the basis pursuit problem. FAL computes a solution to this problem by inexactly solving a sequence of L1-regularized least squares sub-problems. These sub-problems are solved using an infinite memory proximal gradient algorithm wherein each update reduces to "shrinkage" or constrained "shrinkage". We show that FAL converges to an optimal solution of the basis pursuit problem whenever the solution is...
Source: http://arxiv.org/abs/1005.5582v2
Arxiv.org
by Mark D. Roberts
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In a certain sense a perfect fluid is a generalization of a point particle. This leads to the question as to what is the corresponding generalization for extended objects. The lagrangian formulation of a perfect fluid is much generalized and this has as a particular example a fluid which is a classical generalization of a membrane, however there is as yet no indication of any relationship between their quantum theories.
Source: http://arxiv.org/abs/hep-th/0406164v2
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We study twisted ideal sheaves of small length on an irreducible principally polarized abelian surface (T,l). Using Fourier-Mukai techniques we associate certain jumping schemes to such sheaves and completely classify such loci. We give examples of applications to the enumerative geometry of T and show that no smooth genus 5 curve on such a surface can contain a g^1_3. We also describe explicitly the singular divisors in the linear system |2l|.
Source: http://arxiv.org/abs/1107.2549v2
Arxiv.org
by Bing Zeng; Xueming Tang; Chingfang Hsu
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We present a framework for fully-simulatable $h$-out-of-$n$ oblivious transfer ($OT^{n}_{h}$) with security against non-adaptive malicious adversaries. The framework costs six communication rounds and costs at most $40n$ public-key operations in computational overhead. Compared with the known protocols for fully-simulatable oblivious transfer that works in the plain mode (where there is no trusted common reference string available) and proven to be secure under standard model (where there is no...
Source: http://arxiv.org/abs/1005.0043v3
Arxiv.org
by Salvatore Catanese; Emilio Ferrara; Giacomo Fiumara; Francesco Pagano
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The process of design and development of virtual environments can be supported by tools and frameworks, to save time in technical aspects and focusing on the content. In this paper we present an academic framework which provides several levels of abstraction to ease this work. It includes state-of-the-art components we devised or integrated adopting open-source solutions in order to face specific problems. Its architecture is modular and customizable, the code is open-source.
Source: http://arxiv.org/abs/1107.0690v1
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Using ergodic theory, in this paper we present a Gel'fand-type spectral radius formula which states that the joint spectral radius is equal to the generalized spectral radius for a matrix multiplicative semigroup $\bS^+$ restricted to a subset that need not carry the algebraic structure of $\bS^+$. This generalizes the Berger-Wang formula. Using it as a tool, we study the absolute exponential stability of a linear switched system driven by a compact subshift of the one-sided Markov shift...
Source: http://arxiv.org/abs/1107.0124v1
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In a previous paper, we defined an operation $\mu$ that generalizes Turaev's cobracket for loops on a surface. We showed that, in contrast to the cobracket, this operation gives a formula for the minimum number of self-intersections of a loop in a given free homotopy class. In this paper we consider the corresponding question for virtual strings. We show that $\mu$ gives a bound on the minimal self-intersection number of a virtual string which is stronger than a bound given by Turaev's virtual...
Source: http://arxiv.org/abs/1107.4718v1
Arxiv.org
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We review an approach to observation-theory comparisons we call "Taste-Testing." In this approach, synthetic observations are made of numerical simulations, and then both real and synthetic observations are "tasted" (compared) using a variety of statistical tests. We first lay out arguments for bringing theory to observational space rather than observations to theory space. Next, we explain that generating synthetic observations is only a step along the way to the...
Source: http://arxiv.org/abs/1107.2827v1
Arxiv.org
by Jason Baggett; Odile Bastille; Alexei Rybkin
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We discuss a new numerical schema for solving the initial value problem for the Korteweg-de Vries equation for large times. Our approach is based upon the Inverse Scattering Transform that reduces the problem to calculating the reflection coefficient of the corresponding Schr\"odinger equation. Using a step-like approximation of the initial profile and a fragmentation principle for the scattering data, we obtain an explicit recursion formula for computing the reflection coefficient,...
Source: http://arxiv.org/abs/1107.3540v1
Arxiv.org
by Cyril Imbert; Régis Monneau; Hasnaa Zidani
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This paper is concerned with the study of a model case of first order Hamilton-Jacobi equations posed on a "junction", that is to say the union of a finite number of half-lines with a unique common point. The main result is a comparison principle. We also prove existence and stability of solutions. The two challenging difficulties are the singular geometry of the domain and the discontinuity of the Hamiltonian. As far as discontinuous Hamiltonians are concerned, these results seem to...
Source: http://arxiv.org/abs/1107.3250v2
Arxiv.org
by Tomasz Kociumaka; Marcin Kubica; Jakub Radoszewski; Wojciech Rytter; Tomasz Walen
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Periodicity in words is one of the most fundamental areas of text algorithms and combinatorics. Two classical and natural variations of periodicity are seeds and covers (also called quasiperiods). Linear-time algorithms are known for finding all the covers of a word, however in case of seeds, for the past 15 years only an $O(n\log{n})$ time algorithm was known (Iliopoulos, Moore and Park, 1996). Finding an $o(n\log{n})$ time algorithm for the all-seeds problem was mentioned as one of the most...
Source: http://arxiv.org/abs/1107.2422v1
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We review and then combine two aspects of the theory of bundle gerbes. The first concerns lifting bundle gerbes and connections on those, developed by Murray and Gomi. Lifting gerbes represent obstructions against extending the structure group of a principal bundle. The second is the transgression of gerbes to loop spaces, initiated by Brylinski and McLaughlin and with recent contributions of the author. Combining these two aspects, we obtain a new formulation of lifting problems in terms of...
Source: http://arxiv.org/abs/1007.5373v2
Arxiv.org
by Jie Sun; Erik M. Bollt; Mason A. Porter; Marian S. Dawkins
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We formulate a mathematical model for daily activities of a cow (eating, lying down, and standing) in terms of a piecewise affine dynamical system. We analyze the properties of this bovine dynamical system representing the single animal and develop an exact integrative form as a discrete-time mapping. We then couple multiple cow "oscillators" together to study synchrony and cooperation in cattle herds. We comment on the relevant biology and discuss extensions of our model. With this...
Source: http://arxiv.org/abs/1005.1381v2
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by D. T. O'Dea; C. N. Clark; C. R. Contaldi; C. J. MacTavish
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The upcoming generation of cosmic microwave background (CMB) experiments face a major challenge in detecting the weak cosmic B-mode signature predicted as a product of primordial gravitational waves. To achieve the required sensitivity these experiments must have impressive control of systematic effects and detailed understanding of the foreground emission that will influence the signal. In this paper, we present templates of the intensity and polarisation of emission from one of the main...
Source: http://arxiv.org/abs/1107.4612v2
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by Najmul Haque; Munshi G. Mustafa
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Based on the external perturbation that disturbs the system only slightly from its equilibrium position we make the Taylor expansion of the pressure of a quark gas. It turns out that the first term was used in the literature to construct a Hard Thermal Loop perturbation theory (HTLpt) within the variation principle of the lowest order of the thermal mass parameter. Various thermodynamic quantities within the 1-loop HTLpt encountered overcounting of the leading order (LO) contribution and also...
Source: http://arxiv.org/abs/1007.2076v3
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by Alex L. Castro; Wyatt C. Howard
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We consider here the problem of classifying orbits of an action of the dif- feomorphism group of 3-space on a tower of fibrations with P2-fibers that generalize the Monster Tower due to Montgomery and Zhitomirskii. As a corollary we give the first steps towards the problem of classifying Goursat 2-flags of small length. In short, we classify the orbits within the first four levels of the Monster Tower and show that there is a total of 34 orbits at the fourth level in the tower.
Source: http://arxiv.org/abs/1107.4145v1
Arxiv.org
by John Marriner; J. P. Bernstein; Richard Kessler; Hubert Lampeitl; Ramon Miquel; Jennifer Mosher; Robert C. Nichol; Masao Sako; Donald P. Schneider; Mathew Smith
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We describe a new formalism to fit the parameters $\alpha$ and $\beta$ that are used in the SALT2 model to determine the standard magnitudes of Type Ia supernovae. The new formalism describes the intrinsic scatter in Type Ia supernovae by a covariance matrix in place of the single parameter normally used. We have applied this formalism to the Sloan Digital Sky Survey Supernova Survey (SDSS-II) data and conclude that the data are best described by $\alpha=0.135_{-.017}^{+.033}$ and...
Source: http://arxiv.org/abs/1107.4631v2
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by Qun Lin; Hehu Xie
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In this paper, a new type of multi-level correction scheme is proposed for solving eigenvalue problems by finite element method. With this new scheme, the accuracy of eigenpair approximations can be improved after each correction step which only needs to solve a source problem on finer finite element space and an eigenvalue problem on the coarsest finite element space. This correction scheme can improve the efficiency of solving eigenvalue problems by finite element method.
Source: http://arxiv.org/abs/1107.0223v1
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We demonstrate that an extremely small but positive quantum correction, or the Casimir energy, to the cosmological constant can arise from a massive bulk fermion field in the Randall-Sundrum model. Specifically, a cosmological constant doubly descended from the Planck-electroweak hierarchy and as minute as the observed dark energy scale can be naturally achieved without fine-tuning of the bulk fermion mass. To ensure the stabilization of the system, we discuss two stabilization mechanisms under...
Source: http://arxiv.org/abs/1005.1920v3
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We extend Br\"and\'en's recent proof of a conjecture of Stanley and describe a new class of non-linear operators that preserve weak Hurwitz stability and the Laguerre-P\'olya class.
Source: http://arxiv.org/abs/1005.4252v2
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by Blair C. Conn; Anna Pasquali; Emanuela Pompei; Richard R. Lane; André-Nicolas Chené; Rory Smith; Geraint F. Lewis
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We report the serendipitous discovery of a collision ring galaxy, identified as 2MASX J06470249+4554022, which we have dubbed 'Auriga's Wheel', found in a SUPRIME-CAM frame as part of a larger Milky Way survey. This peculiar class of galaxies is the result of a near head-on collision between typically, a late type and an early type galaxy. Subsequent GMOS-N long-slit spectroscopy has confirmed both the relative proximity of the components of this interacting pair and shown it to have a redshift...
Source: http://arxiv.org/abs/1107.4099v2
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Assuming that the universe is homogenous and isotropic and applying Gauss' flux theorem for gravity, it follows that the gravitational field of the visible universe can be calculated as if the entire mass of the visible universe is located in one point. Taking into account that the mass of the visible universe is M=2x10^{53} kg, it appears that the entire visible universe is inside a {\it photon sphere} of radius R_{ps} = 14.3 Gpc. The current model for the visible universe must be corrected to...
Source: http://arxiv.org/abs/1005.4387v9
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For every natural number $T,$ we write $\Ln T$ as a series, generalizing the known series for $\Ln 2.$
Source: http://arxiv.org/abs/1107.4731v1
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We employ the method used by Barbashov and collaborators in Quantum Field Theory to derive a path-integral representation of the $T$-matrix in nonrelativistic potential scattering which is free of functional integration over fictitious variables as was necessary before. The resulting expression serves as a starting point for a variational approximation applied to high-energy scattering from a Gaussian potential. Good agreement with exact partial-wave calculations is found even at large...
Source: http://arxiv.org/abs/1107.3034v2
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by John D. Barrow; Douglas J. Shaw
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We extend the usual gravitational action principle by promoting the bare cosmological constant (CC) from a parameter to a field which can take many possible values. Variation leads to a new integral constraint equation which determines the classical value of the effective CC that dominates the wave function of the universe. In a realistic cosmological model, the expected value of the effective CC, is calculated from measurable quantities to be O(t_U), as observed, where t_U is the present age...
Source: http://arxiv.org/abs/1007.3086v3
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This paper presents a new classifier combination technique based on the Dempster-Shafer theory of evidence. The Dempster-Shafer theory of evidence is a powerful method for combining measures of evidence from different classifiers. However, since each of the available methods that estimates the evidence of classifiers has its own limitations, we propose here a new implementation which adapts to training data so that the overall mean square error is minimized. The proposed technique is shown to...
Source: http://arxiv.org/abs/1107.0018v1
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by Philip R. Heath; P. Christopher Staecker
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As the title suggests, this paper gives a Nielsen theory of coincidences of iterates of two self maps f, g of a closed manifold. The ideas is, as much as possible, to generalize Nielsen type periodic point theory, but there are many obstacles. Many times we get similar results to the "classical ones" in Nielsen periodic point theory, but with stronger hypotheses.
Source: http://arxiv.org/abs/1107.5510v1
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by Yochay Jerby
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A classical way to construct a Lagrangian in a symplectic manifold $\Sigma$ is to let $\Sigma$ appear as a smooth fiber in a Lefschetz fibration. If this is possible the singularities of the fibration induce Lagrangian spheres in $\Sigma$ and these spheres, in turn, are representatives of the corresponding vanishing cycles in the homology of $\Sigma$. In this paper our aim is twofold: The first is to describe a generalization of the above mentioned construction to the "Morse-Bott"...
Source: http://arxiv.org/abs/1005.5657v3
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by Selman Akbulut; M. Firat Arikan
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Loi-Piergallini and Akbulut-Ozbagci showed that every compact Stein surface admits a Lefschetz fibration over the 2-disk with bounded fibers. In this note we give a more intrinsic alternative proof of this result.
Source: http://arxiv.org/abs/1007.3643v3
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by U. Battisti; S. Coriasco
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We prove an extension to R^n, endowed with a suitable metric, of the relation between the Einstein-Hilbert action and the Dirac operator which holds on closed spin manifolds. By means of complex powers, we first define the regularised Wodzicki Residue for a class of operators globally defined on R^n. The result is then obtained by using the properties of heat kernels and generalised Laplacians.
Source: http://arxiv.org/abs/1007.1797v2
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by Felipe Cucker; Teresa Krick; Gregorio Malajovich; Mario Wschebor
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In a recent paper (Cucker, Krick, Malajovich and Wschebor, A Numerical Algorithm for Zero Counting. I: Complexity and accuracy, J. Compl.,24:582-605, 2008) we analyzed a numerical algorithm for computing the number of real zeros of a polynomial system. The analysis relied on a condition number kappa(f) for the input system f. In this paper, we look at kappa(f) as a random variable derived from imposing a probability measure on the space of polynomial systems and give bounds for both the tail...
Source: http://arxiv.org/abs/1007.1597v2
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by Yaroslav D. Sergeyev; Dmitri E. Kvasov; Falah M. H. Khalaf
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Lipschitz one-dimensional constrained global optimization (GO) problems where both the objective function and constraints can be multiextremal and non-differentiable are considered in this paper. Problems, where the constraints are verified in an a priori given order fixed by the nature of the problem are studied. Moreover, if a constraint is not satisfied at a point, then the remaining constraints and the objective function can be undefined at this point. The constrained problem is reduced to...
Source: http://arxiv.org/abs/1107.5280v1
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by M. H. Goker; P. Langley; C. A. Thompson
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Searching for and making decisions about information is becoming increasingly difficult as the amount of information and number of choices increases. Recommendation systems help users find items of interest of a particular type, such as movies or restaurants, but are still somewhat awkward to use. Our solution is to take advantage of the complementary strengths of personalized recommendation systems and dialogue systems, creating personalized aides. We present a system -- the Adaptive Place...
Source: http://arxiv.org/abs/1107.0029v1
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by Claudio M. G. de Sousa; Evandro A. de Araujo
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We use standard polynomial expansion technique to show the existence of a relation between polytropic model and the description of gas spheres at finite temperature. A numerical analysis is made concerning the obtained perturbative parameters. It is shown that there is a correspondence between polytropic and gas sphere thermal models for fermions and bosons. For instance, the polytropic index $n$ displays evident correlation with temperature and chemical potential.
Source: http://arxiv.org/abs/1007.1994v2
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by Andreas Eckstein; Benjamin Brecht; Christine Silberhorn
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We introduce the concept of a quantum pulse gate (QPG), a method for accessing the intrinsic broadband spectral mode structure of ultrafast quantum states of light. This mode structure can now be harnessed for applications in quantum information processing. We propose an implementation in a PPLN waveguide, based on spectrally engineered sum frequency generation (SFG). It allows us to pick well-defined spectral broadband modes from an ultrafast multi-mode state for interconversion to a broadband...
Source: http://arxiv.org/abs/1007.3215v2
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by M. V. Chizhov
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A simple reference model for anomalously interacting bosons is proposed and implemented in the CompHEP package. This allows preparing for an experimental search of these bosons at powerful colliders, such as Tevatron and LHC. New signatures and some experimental consequences are shortly considered.
Source: http://arxiv.org/abs/1005.4287v2
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To implicitly restart the second-order Arnoldi (SOAR) method proposed by Bai and Su for the quadratic eigenvalue problem (QEP), it appears that the SOAR procedure must be replaced by a modified SOAR (MSOAR) one. However, implicit restarts fails to work provided that deflation takes place in the MSOAR procedure. In this paper, we first propose a Refined MSOAR (abbreviated as RSOAR) method that is based on the refined projection principle. We derive upper bounds for residual norms of the...
Source: http://arxiv.org/abs/1005.3947v3
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by David Alba; Horace W. Crater; Luca Lusanna
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We define a relativistic version of the two-level atom, in which an extended atom is replaced by a point particle carrying suitable Grassmann variables for the description of the two-level structure and of the electric dipole. After studying the isolated system "atom plus the electro-magnetic field" in the electric-dipole representation as a parametrized Minkowski theory, we give its restriction to the inertial rest frame and the explicit form of the Poincar\'e generators. After...
Source: http://arxiv.org/abs/1107.1669v1
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by Michael C. Liu; Niall R. Deacon; Eugene A. Magnier; Trent J. Dupuy; Kimberly M. Aller; Brendan P. Bowler; Bertrand Goldman; W. S. Burgett; K. C. Chambers; K. W. Hodapp; N. Kaiser; R. -P. Kudritzki; J. S. Morgan; P. A. Price; J. L. Tonry; R. J. Wainscoat
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We have searched ~8200 sq. degs for high proper motion (~0.5-2.7"/year) T dwarfs by combining first-epoch data from the Pan-STARRS1 (PS1) 3-Pi Survey, the 2MASS All-Sky Point Source Catalog, and the WISE Preliminary Data Release. We identified two high proper motion objects with the very red (W1-W2) colors characteristic of T dwarfs, one being the known T7.5 dwarf GJ 570D. Near-IR spectroscopy of the other object (PSO J043.5+02 = WISEP J0254+0223) reveals a spectral type of T8, leading to...
Source: http://arxiv.org/abs/1107.4608v3
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by Antara R. Basu-Zych; Ann E. Hornschemeier; Erik A. Hoversten; Bret Lehmer; Caryl Gronwall
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(Abridged) While the Swift satellite is primarily designed to study gamma-ray bursts, its ultraviolet and optical imaging and spectroscopy capabilities are also being used for a variety of scientific programs. In this study, we use the UV/Optical Telescope (UVOT) instrument aboard Swift to discover 0.560ks exposure time, achieving a limiting magnitude of u
Source: http://arxiv.org/abs/1107.3849v1
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by Scott Sheppard; Andrzej Udalski; Chad Trujillo; Marcin Kubiak; Grzegorz Pietrzynski; Radoslaw Poleski; Igor Soszynski; Michal Szyma; Krzysztof Ulaczyk
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About 2500 square degrees of sky south of declination -25 degrees and/or near the galactic plane were surveyed for bright outer solar system objects. This survey is one of the first large scale southern sky and galactic plane surveys to detect dwarf planets and other bright Kuiper Belt objects in the trans-Neptunian region. The survey was able to obtain a limiting R-band magnitude of 21.6. In all, 18 outer solar system objects were detected, including Pluto which was detected near the galactic...
Source: http://arxiv.org/abs/1107.5309v1
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by A. Elmaslı; L. Fossati; C. P. Folsom; B. Albayrak; H. Izumiura
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The Ursa Major group is a nearby stellar supercluster which, while not gravitationally bound, is defined by co-moving members. DD UMa is a $\delta$ Scuti star whose membership in the Ursa Major group is unclear. The objective of this study is to confirm the membership of DD UMa in the Ursa Major group, as well as perform a detailed spectral analysis of the star. Since DD UMa is a low-amplitude $\delta$ Scuti star, we performed a frequency analysis. We determined fundamental parameters, chemical...
Source: http://arxiv.org/abs/1107.4856v1
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by François Mériaux; Maël Le Treust; Samson Lasaulce; Michel Kieffer
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Frequency non-selective time-selective multiple access channels in which transmitters can freely choose their power control policy are considered. The individual objective of the transmitters is to maximize their averaged energy-efficiency. For this purpose, a transmitter has to choose a power control policy that is, a sequence of power levels adapted to the channel variations. This problem can be formulated as a stochastic game with discounting for which there exists a theorem characterizing...
Source: http://arxiv.org/abs/1107.4258v1
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by José A. Muñoz; Evencio Mediavilla; Christopher S. Kochanek; Emilio Falco; Ana María Mosquera
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We report Hubble Space Telescope observations of 6 gravitational lenses with the Advanced Camera for Surveys. We measured the flux ratios between the lensed images in 6 filters from 8140\AA\ to 2200\AA. In 3 of the systems, HE0512$-$3329, B1600+434, and H1413+117, we were able to construct UV extinction curves partially overlapping the 2175\AA\ feature and characterize the properties of the dust relative to the Galaxy and the Magellanic Clouds. In HE1104$-$1804 we detect chromatic microlensing...
Source: http://arxiv.org/abs/1107.5932v1
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The statistical meaning of the local non-Gaussianity parameters f_NL and g_NL is examined in detail. Their relations to the skewness and the kurtosis of the probability distribution of density fluctuations are shown to obey simple fitting formulae, accurate on galaxy-cluster scales. We argue that the knowledge of f_NL and g_NL is insufficient for reconstructing a well-defined distribution of density fluctuations. However, by weakening the statistical significance of f_NL and g_NL, it is...
Source: http://arxiv.org/abs/1007.1230v5
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by Shu-Ping Yan; Jin-Lu Qu; Guo-Qiang Ding; Peng Han; Li-Ming Song; Hong-Xing Yin; Cheng-Min Zhang; Shu Zhang; Jian-Min Wang
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Systematically studying all the RXTE/PCA observations for GRS 1915+105 before November 2010, we have discovered three additional patterns in the relation between Quasi-Periodic Oscillation (QPO) frequency and photon energy, extending earlier outcomes reported by Qu et al. (2010). We have confirmed that as QPO frequency increases, the relation evolves from the negative correlation to positive one. The newly discovered patterns provide new constraints on the QPO models.
Source: http://arxiv.org/abs/1107.3621v2
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by A. Dinesh Kumar; Ambedkar Dukkipati
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Low density parity-check (LDPC) codes are a class of linear block codes that are decoded by running belief propagation (BP) algorithm or log-likelihood ratio belief propagation (LLR-BP) over the factor graph of the code. One of the disadvantages of LDPC codes is the onset of an error floor at high values of signal to noise ratio caused by trapping sets. In this paper, we propose a two stage decoder to deal with different types of trapping sets. Oscillating trapping sets are taken care by the...
Source: http://arxiv.org/abs/1107.2867v1
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by Serkan Araci; Mehmet Açikgöz; Hassan Jolany; Jong Jin Seo
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The purpose of this paper is to construct of the unification q-extension Genocchi polynomials. We give some interesting relations of this type of polynomials. Finally, we derive the q-extensions of Hurwitz-zeta type functions from the Mellin transformation of this generating function which interpolates the unification of q-extension of Genocchi polynomials.
Source: http://arxiv.org/abs/1107.5950v1
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by N. S. Nikolaidis; I. N. Nikolaidis; C. C. Tsouros
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The box counting method for fractal dimension estimation had not been applied to large or colour images thus far due to the processing time required. In this letter we present a fast, easy to implement and very easily expandable to any number of dimensions variation, the box merging method. It is applied here in RGB images which are considered as sets in 5-D space.
Source: http://arxiv.org/abs/1107.2336v1
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by Olivier Bernardi; Eric Fusy
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A $d$-angulation is a planar map with faces of degree $d$. We present for each integer $d\geq 3$ a bijection between the class of $d$-angulations of girth $d$ (i.e., with no cycle of length less than $d$) and a class of decorated plane trees. Each of the bijections is obtained by specializing a "master bijection" which extends an earlier construction of the first author. Our construction unifies known bijections by Fusy, Poulalhon and Schaeffer for triangulations ($d=3$) and by...
Source: http://arxiv.org/abs/1007.1292v6
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by Bernard A. Anderson; Barbara F. Csima
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We define the bounded jump of A by A^b = {x | Exists i 1 we have X
Source: http://arxiv.org/abs/1007.3692v2
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by Hirotake Kurihara; Hiroshi Nozaki
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We prove a necessary and sufficient condition for a symmetric association scheme to be a Q-polynomial scheme.
Source: http://arxiv.org/abs/1007.0473v2
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Let (G, *) be a semigroup, D subset of G, and n >= 2 be an integer. We say that (D, *) is an n-closed subset of G if a_1* ... *a_n in D for every a_1, ..., a_n in D. Hence every closed set is a 2-closed set. The concept of n-closed sets arise in so many natural examples. For example, let D be the set of all odd integers, then (D, +) is a 3-closed subset of (Z, +) that is not a 2-closed subset of (Z, +). If K = {1, 4, 7, 10, ...}, then (K, +) is a 4-closed subset of (Z, +) that is not an...
Source: http://arxiv.org/abs/1107.5058v1
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We consider a nonrelativistic quantum charged particle moving on a plane under the influence of a uniform magnetic field and driven by a periodically time-dependent Aharonov-Bohm flux. We observe an acceleration effect in the case when the Aharonov-Bohm flux depends on time as a sinusoidal function whose frequency is in resonance with the cyclotron frequency. In particular, the energy of the particle increases linearly for large times. An explicit formula for the acceleration rate is derived...
Source: http://arxiv.org/abs/1107.2861v1
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by Robert Haslhofer; Reto Müller
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We prove precompactness in an orbifold Cheeger-Gromov sense of complete gradient Ricci shrinkers with a lower bound on their entropy and a local integral Riemann bound. We do not need any pointwise curvature assumptions, volume or diameter bounds. In dimension four, under a technical assumption, we can replace the local integral Riemann bound by an upper bound for the Euler characteristic. The proof relies on a Gauss-Bonnet with cutoff argument.
Source: http://arxiv.org/abs/1005.3255v3
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A comparative study by FP-LAPW calculations based on DFT within LDA, PBE-GGA, EV$_{ex}$-PW$_{co}$-GGA, and EV$_{ex}$-GGA-LDA$_{co}$ schemes is introduced for the structural and electronic properties of ScN in RS, ZB, WZ, and CsCl phases. According to all approximations used in this work, the RS phase is the stable ground state structure and makes a transition to CsCl phase at high transition pressure. While PBE-GGA and EV$_{ex}$-PW$_{co}$-GGA's have provided better structural features such as...
Source: http://arxiv.org/abs/1107.0590v1
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by François Arnault
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We give a multidimensional generalisation of the complete set of Bell-correlation inequalities given by Werner and Wolf, and by Zukowski and Brukner, for the two-dimensional case. Our construction applies for the n parties, two-observables case, where each observable is d-valued. The d^{d^n} inequalities obtained involve homogeneous polynomials. They define the facets of a polytope in a complex vector space of dimension d^n. We also show that these inequalities are violated by Quantum...
Source: http://arxiv.org/abs/1107.2255v2
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Motivated by the experimental measurement of electrical and hall conductivity, thermopower and Nernst effect, we calculate the longitudinal and transverse electrical and heat transport in graphene in the presence of unitary scatterers as well as charged impurities. The temperature and carrier density dependence in this system display a number of anomalous features that arise due to the relativistic nature of the low energy fermionic degrees of freedom. We derive the properties in detail...
Source: http://arxiv.org/abs/1007.3533v2
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by Carsten Gundlach; Ian Hawke; Stephanie J. Erickson
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We present a practical framework for ideal hyperelasticity in numerical relativity. For this purpose, we recast the formalism of Carter and Quintana as a set of Eulerian conservation laws in an arbitrary 3+1 split of spacetime. The resulting equations are presented as an extension of the standard Valencia formalism for a perfect fluid, with additional terms in the stress-energy tensor, plus a set of kinematic conservation laws that evolve a configuration gradient. We prove that the equations...
Source: http://arxiv.org/abs/1107.2551v1
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by Eduardo J. Dubuc; Sergio Yuhjtman
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We show the existence of bilimits of 2-cofiltered diagrams of topoi, generalizing the construction of cofiltered bilimits developed in "SGA 4 Springer LNM 270 (1972)". For any given such diagram, we show that it can be represented by a 2-cofiltered diagram of small sites with finite limits, and we construct a small site for the inverse limit topos. This is done by taking the 2-filtered bicolimit of the underlying categories and inverse image functors. We use the construction of this...
Source: http://arxiv.org/abs/1107.1685v1
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Recently, Hu and Xi have exhibited derived equivalent endomorphism rings arising from (relative) almost split sequences as well as AR-triangles in triangulated categories. We present a more general class of triangles (in algebraic triangulated categories) for which the endomorphism rings of different terms are derived equivalent. In particular, applying this result in the category of perfect complexes over a symmetric algebra gives a new way of producing pairs of derived equivalent symmetric...
Source: http://arxiv.org/abs/1005.5152v3
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by Julia Stasińska; Simone Paganelli; Carles Rodó; Anna Sanpera
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Quantum interfaces between polarized atomic ensembles and coherent states of light, applied recently to manipulate bipartite and multipartite entanglement, are revisited by means of a continuous-variable formalism. The explicit use of the continuous-variable formalism facilitates significantly the analysis of entanglement between different modes, reducing it to the study of the properties of a final covariance matrix which can be found analytically. Furthermore, it allows to study matter-light...
Source: http://arxiv.org/abs/1007.0403v3
For every Gaussian network, there exists a corresponding deterministic network called the discrete superposition network. We show that this discrete superposition network provides a near-optimal digital interface for operating a class consisting of many Gaussian networks in the sense that any code for the discrete superposition network can be naturally lifted to a corresponding code for the Gaussian network, while achieving a rate that is no more than a constant number of bits lesser than the...
Source: http://arxiv.org/abs/1005.0167v2
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by Klaas Vantournhout; Natalie Jachowicz; Jan Ryckebusch
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We present a method that offers perspectives to perform fully antisymmetrized simulations for inhomogeneous bulk fermion matter. The technique bears resemblance to classical periodic boundary conditions, using localized single-particle states. Such localized states are an ideal tool to discuss phenomena where spatial localization plays an important role. The antisymmetrisation is obtained introducing a doubly-periodic structure in the many-body fermion wave functions. This results in circulant...
Source: http://arxiv.org/abs/1005.2235v2
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by Fredrik Andersson; Marcus Carlsson; Per-Anders Ivert
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The problem of approximating a sampled function using sums of a fixed number of complex exponentials is considered. We use alternating projections between fixed rank matrices and Hankel matrices to obtain such an approximation. Convergence, convergence rates and error estimates for this technique are proven, and fast algorithms are developed. We compare the numerical results obtain with the MUSIC and ESPRIT methods.
Source: http://arxiv.org/abs/1107.2028v1
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In this paper, we prove a general halfspace theorem for constant mean curvature surfaces. Under certain hypotheses, we prove that, in an ambient space M^3, any constant mean curvature H_0 surface on one side of a constant mean curvature H_0 surface \Sigma_0 is an equidistant surface to \Sigma_0. The main hypotheses of the theorem are that \Sigma_0 is parabolic and the mean curvature of the equidistant surfaces to \Sigma_0 evolves in a certain way.
Source: http://arxiv.org/abs/1007.2559v3
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by Jorge Erick López; Carlos Gustavo Moreira
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We prove the following variant of Marstrand's theorem about projections of cartesian products of sets: Let $K_1,...,K_n$ Borel subsets of $\mathbb R^{m_1},... ,\mathbb R^{m_n}$ respectively, and $\pi:\mathbb R^{m_1}\times...\times\mathbb R^{m_n}\to\mathbb R^k$ be a surjective linear map. We set $$\mathfrak{m}:=\min\{\sum_{i\in I}\dim_H(K_i) + \dim\pi(\bigoplus_{i\in I^c}\mathbb R^{m_i}), I\subset\{1,...,n\}, I\ne\emptyset\}.$$ Consider the space $\Lambda_m=\{(t,O), t\in\mathbb R, O\in SO(m)\}$...
Source: http://arxiv.org/abs/1107.0424v1
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In a recent paper, Michalowicz et al. provide an extension of Isserlis theorem to the case of a Bernoulli location mixture of a Gaussian vector. We extend here this result to the case of any location mixture of Gaussian vector; we also provide an example of the Isserlis theorem for a "scale location" mixture of Gaussian, namely the d-dimensional generalized hyperbolic distribution.
Source: http://arxiv.org/abs/1107.2309v1