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Effects of high vs moderate-intensity training on neuroplasticity and functional recovery after focal ischemiaFeb 08 2018Background and Purpose: This study was designed to compare the effects of high-intensity interval training (HIT) and moderate-intensity continuous training (MOD) on functional recovery and cerebral plasticity during the first 2 weeks following cerebral ... More

Surgery on discrete groupsNov 25 2016We study constructions of groups, in particular of groups of intermediate rank, which are accessible to surgery techniques.

Aut(F2) puzzlesOct 28 2014This paper studies Aut(F2) and groups closely related to it from a geometric perspective.

Removing chambers in Bruhat-Tits buildingsMar 24 2010Nov 11 2012We introduce and study a family of countable groups constructed from Euclidean buildings by "removing" suitably chosen subsets of chambers.

Random groups and nonarchimedean latticesAug 10 2013Sep 24 2014We consider models of random groups in which the typical group is of intermediate rank (in particular, it is not hyperbolic). These models are parallel to M. Gromov's well-known constructions and include for example a "density model" for groups of intermediate ... More

Breathers and solitons of generalized nonlinear Schrödinger equations as degenerations of algebro-geometric solutionsJun 01 2011We present new solutions in terms of elementary functions of the multi-component nonlinear Schr\"odinger equations and known solutions of the Davey-Stewartson equations such as multi-soliton, breather, dromion and lump solutions. These solutions are given ... More

Un critère de récurrence pour certains espaces homogènesJul 19 2016Let $G$ be a real connected algebraic semi-simple Lie group, and $H$ an algebraic subgroup of $G$. Let $\mu$ be a probability measure on $G$, with finite exponential moment, whose support spans a Zariski-dense subsemigroup of $G$. Let $X=G/H$ be the quotient ... More

The Maskit embedding of the twice punctured torusAug 15 2008The Maskit embedding M of a surface \Sigma is the space of geometrically finite groups on the boundary of quasifuchsian space for which the `top' end is homeomorphic to \Sigma, while the `bottom' end consists of two triply punctured spheres, the remains ... More

Threshold graphs, shifted complexes, and graphical complexesMar 04 2007We consider a variety of connections between threshold graphs, shifted complexes, and simplicial complexes naturally formed from a graph. These graphical complexes include the independent set, neighborhood, and dominance complexes. We present a number ... More

La propriete de decroissance rapide pour le groupe de WiseNov 11 2012We show that the group of presentation $< a,b,c,s,t\mid c=ab=ba,\, c^2=sas^{-1}=tbt^{-1}>$ (introduced by D. Wise) has the property of rapid decay.

Results from H.E.S.S. Observations of Relativistic SourcesJun 24 2010The High Energy Stereoscopic System (H.E.S.S.) is a southern hemisphere array of four Imaging Atmospheric Cherenkov Telescopes observing the sky in the very high energy gamma-ray range (E $>$ 100 GeV). VHE observations are an invaluable tool to study ... More

Twisted gamma filtration and algebras with orthogonal involutionNov 14 2012For the Grothendieck group of a split simple linear algebraic group, the twisted gamma-filtration provides a useful tool for constructing torsion elements in gamma-rings of twisted flag varieties. In this paper, we construct a non-trivial torsion element ... More

Un contre-exemple à la dichotomie récurrence/transience sur les espaces homogènesJul 19 2016Take $G$ a locally compact second-countable group, and $H$ a subgroup of $G$. Choose $\mu$ a probability measure on $G$, such that the group spanned by its support is dense in $G$, and consider the Markov chain on the homogeneous space $X=G/H$ with transition ... More

The J-invariant and Tits algebras for groups of inner type E6Dec 07 2011Jan 30 2012A connection between the indices of the Tits algebras of a split linear algebraic group G and the degree one parameters of its motivic J-invariant was introduced by Queguiner-Mathieu, Semenov and Zainoulline through use of the second Chern class map in ... More

Geometry of maximum likelihood estimation in Gaussian graphical modelsDec 13 2010May 29 2012We study maximum likelihood estimation in Gaussian graphical models from a geometric point of view. An algebraic elimination criterion allows us to find exact lower bounds on the number of observations needed to ensure that the maximum likelihood estimator ... More

Quantum Measurements Cannot be Proved to be RandomAug 30 2010We show that it is impossible to prove that the outcome of a quantum measurement is random.

Dilatonic String through black holesNov 19 1999We study the gravi-dilaton field of a Schwarzschild black hole pierced by a thin cosmic string in both massless and massive dilatonic gravity. We conclude that in the thin vortex approximation the string's spacetime is asymptotically flat with a conical ... More

Static black holes in scalar tensor gravitySep 15 2000We study static black hole solutions in scalar tensor gravity. We present exact solutions in hiperextended models with a quadratic scalar potential.

About the dynamics and thermodynamics of trapped ionsFeb 16 2009May 14 2009This tutorial introduces the dynamics of charged particles in a radiofrequency trap in a very general manner to point out the differences between the dynamics in a quadrupole and in a multipole trap. When dense samples are trapped, the dynamics is modified ... More

Network Robustness: Detecting Topological Quantum PhasesAug 06 2014Can the topology of a network that consists of many particles interacting with each other change in complexity when a phase transition occurs? The answer to this question is particularly interesting to understand the nature of phase transitions if the ... More

Lifting to cluster-tilting objects in 2-Calabi-Yau triangulated categoriesDec 14 2007Dec 29 2007We show that a tilting module over the endomorphism algebra of a cluster-tilting object in a 2-Calabi-Yau triangulated category lifts to a cluster-tilting object in this 2-Calabi-Yau triangulated category. This generalizes a recent work of D. Smith for ... More

On high order accurate schemes for space fractional diffusion equations with variable coefficientsAug 29 2016Oct 14 2016We study high order schemes for spatial fractional differential equations with variable coefficients. Approximations of fractional derivatives basing on the weighted and shifted Gr\"unwald-Letnikov formulas and weighted and shifted Lubich formulas are ... More

Variational Monte Carlo simulation in hole-doped cuprate superconductors: Competition between antiferromagnetism and superconductivityJun 16 2015We present variational Monte Carlo (VMC) results for the Gutzwiller-projected coexisting state including both antiferromagnetic (AFM) order and superconducting (SC) order in the two-dimensional t-t'-t"-J model. By further considering off-site spin correlation ... More

Thurston's bending measure conjecture for once punctured torus groupsJun 03 2004We prove Thurston's bending measure conjecture for quasifuchsian once punctured torus groups. The conjecture states that the bending measures of the two components of the convex hull boundary uniquely determine the group.

Cosmic strings in axionic-dilatonic gravitySep 29 2000Oct 03 2000We first consider local cosmic strings in dilaton-axion gravity and show that they are singular solutions. Then we take a supermassive Higgs limit and present expressions for the fields at far distances from the core by applying a Pecci-Quinn and a duality ... More

On high order accurate schemes for space fractional diffusion equations with variable coefficientsAug 29 2016Sep 29 2016We study high order schemes for spatial fractional differential equations with variable coefficients. Approximations of fractional derivatives basing on the weighted and shifted Gr\"unwald-Letnikov formulas and weighted and shifted Lubich formulas are ... More

Quantum Lefschetz Hyperplane TheoremMar 21 2000Dec 06 2000The mirror theorem is generalized to any smooth projective variety X. That is, a fundamental relation between the Gromov-Witten invariants of X and Gromov-Witten invariants of complete intersections Y in X is established.

A Large Data Regime for non-linear Wave EquationsOct 07 2012For semi-linear wave equations with null form non-linearities on $\mathbb{R}^{3+1}$, we exhibit an open set of initial data which are allowed to be large in energy spaces, yet we can still obtain global solutions in the future. We also exhibit a set of ... More

Almost-Prime Polynomials with Prime ArgumentsJun 11 2016We improve Irving's method of the double-sieve by using the DHR sieve. By extending the upper and lower sieve functions into their respective non-elementary ranges, we are able to make improvements on the previous records on the number of prime factors ... More

Tunneling magnetoresistance in diluted magnetic semiconductor tunnel junctionsJan 15 2001Using the spin-polarized tunneling model and taking into account the basic physics of ferromagnetic semiconductors, we study the temperature dependence of the tunneling magnetoresistance (TMR) in the diluted magnetic semiconductor (DMS) trilayer heterostructure ... More

Heights and the Specialization Map for Families of Elliptic Curves over P^nSep 10 2014Jun 22 2015For $n\geq 2$, let $K=\overline{\mathbb{Q}}(\mathbb{P}^n)=\overline{\mathbb{Q}}(T_1, \ldots, T_n)$. Let $E/K$ be the elliptic curve defined by a minimal Weiestrass equation $y^2=x^3+Ax+B$, with $A,B \in \overline{\mathbb{Q}}[T_1, \ldots, T_n]$. There's ... More

Robustness of complex many-body networks: Novel perspective in 2D metal-insulator transitionFeb 10 2014May 27 2014We present a novel theoretical framework established by complex network analysis for understanding the phase transition beyond the Landau symmetry breaking paradigm. In this paper we take a two-dimensional metal-insulator transition driven by electron ... More

New Approaches to Honesty Theory and Applications in Quantum Dynamical SemigroupsJul 24 2015We prove some new characterisations of honesty of the perturbed semigroup in Kato's Perturbation Theorem on abstract state spaces via three approaches, namely mean ergodicity of operators, adjoint operators and uniqueness of the perturbed semigroup. We ... More

On algebraic damping close to inhomogeneous Vlasov equilibria in multi-dimensional spacesOct 30 2012We investigate the asymptotic damping of a perturbation around inhomogeneous stable stationary states of the Vlasov equation in spatially multi-dimensional systems. We show that branch singularities of the Fourier-Laplace transform of the perturbation ... More

The cosmological perturbation theory in loop cosmology with holonomy correctionsJan 08 2010May 21 2010In this paper we investigate the scalar mode of first-order metric perturbations over spatially flat FRW spacetime when the holonomy correction is taken into account in the semi-classical framework of loop quantum cosmology. By means of the Hamiltonian ... More

Thermal non-Gaussianity in holographic cosmologySep 19 2008Nov 03 2008Recently it has been shown that the thermal holographic fluctuations can give rise to an almost scale invariant spectrum of metric perturbations since in this scenario the energy is proportional to the area of the boundary rather than the volume. Here ... More

Profit Incentive In A Secondary Spectrum Market: A Contract Design ApproachJul 27 2012In this paper we formulate a contract design problem where a primary license holder wishes to profit from its excess spectrum capacity by selling it to potential secondary users/buyers. It needs to determine how to optimally price the excess spectrum ... More

A Simple Method to Test for Energy-Dependent Dispersion in High Energy Light-Curves of Astrophysical SourcesApr 10 2012In this paper we discuss a simple method of testing for the presence of energy-dependent dispersion in high energy data-sets. It uses the minimisation of the Kolmogorov distance between the cumulative distribution of two probability functions as the statistical ... More

The Onsager AlgebraMay 27 2012In this thesis, four realizations of the Onsager algebra are explored. We begin with its original definition as introduced by Lars Onsager. We then examine how the Onsager algebra can be presented as a Lie algebra with two generators and two relations. ... More

Quasi-Periodic Oscillations in magnetars: linking variability and emissionOct 24 2012I present recent results studying flare emission in magnetars. Strong quasi-periodic oscillations observed in the tail of giant magnetar flares are frequently interpreted as evidence for global seismic oscillations. I demonstrate that such a global oscillation ... More

Keyphrase Extraction : Enhancing ListsApr 01 2012This paper proposes some modest improvements to Extractor, a state-of-the-art keyphrase extraction system, by using a terabyte-sized corpus to estimate the informativeness and semantic similarity of keyphrases. We present two techniques to improve the ... More

Abundances and ages of the deconvolved thin/thick disks of the GalaxyNov 02 2004We have investigated the abundance of several chemical elements in two large stellar samples kinematically representative of the thin and the thick disks of the Galaxy. Chemical, kinematical and age data have been collected from high quality sources in ... More

Limit points of lines of minima in Thurston's boundary of Teichmueller spaceMar 09 2003Given two measured laminations mu and nu in a hyperbolic surface which fill up the surface, Kerckhoff [Lines of Minima in Teichmueller space, Duke Math J. 65 (1992) 187-213] defines an associated line of minima along which convex combinations of the length ... More

Concept Clustering and Knowledge Integration from a Children's DictionaryMar 05 1997Knowledge structures called Concept Clustering Knowledge Graphs (CCKGs) are introduced along with a process for their construction from a machine readable dictionary. CCKGs contain multiple concepts interrelated through multiple semantic relations together ... More

Is the United States losing ground in science? A global perspective on the world science systemNov 05 2009Based on the Science Citation IndexExpanded webversion, the USA is still by far the strongest nation in terms of scientific performance. Its relative decline in percentage share of publications is largely due to the emergence of China and other Asian ... More

Macro-level Indicators of the Relations between Research Funding and Research OutputNov 05 2009In response to the call for a science of science policy, we discuss the contribution of indicators at the macro-level of nations from a scientometric perspective. In addition to global trends such as the rise of China, one can relate percentages of world ... More

The Chaotic Ball: An Intuitive Analogy for EPR ExperimentsNov 21 1996Aug 08 2004Actual realisations of EPR experiments do {\em not} demonstrate non-locality. A model is presented that should enable non-specialists as well as specialists to understand how easy it is to find realistic explanations for the observations. The model also ... More

Homodyne detection and parametric down-conversion: a classical approach applied to proposed "loophole-free" Bell testsAug 02 2005A classical model is presented for the features of parametric down-conversion and homodyne detection relevant to recent proposed ``loophole-free'' Bell tests. The Bell tests themselves are uncontroversial: there are no obvious loopholes that might cause ... More

Cosmic strings in dilaton gravityJan 09 1997Jun 06 1997We examine the metric of an isolated self-gravitating abelian-Higgs vortex in dilatonic gravity for arbitrary coupling of the vortex fields to the dilaton. We look for solutions in both massless and massive dilaton gravity. We compare our results to existing ... More

Top terms of polynomial traces in Kra's plumbing constructionJan 14 2010Let $\Sigma$ be a surface of negative Euler characteristic together with a pants decomposition $\P$. Kra's plumbing construction endows $\Sigma$ with a projective structure as follows. Replace each pair of pants by a triply punctured sphere and glue, ... More

A tree metric using structure and length to capture distinct phylogenetic signalsJul 18 2015Sep 11 2015Phylogenetic trees are a central tool in understanding evolution. They are typically inferred from sequence data, and capture evolutionary relationships through time. It is essential to be able to compare trees from different data sources (e.g. several ... More

Cohomology of generalized supergrassmannians and character formulae for basic classical Lie superalgebrasJun 04 2009Jun 22 2009In this paper, we use geometrical methods adapted from the Borel-Weil-Bott theory to compute the character of every finite dimensional simple module over a basic classical Lie superalgebra.

Propagation of Quantum Expectations with Husimi FunctionsJul 31 2012Mar 17 2013We analyse the dynamics of expectation values of quantum observables for the time-dependent semiclassical Schr\"odinger equation. To benefit from the positivity of Husimi functions, we switch between observables obtained from Weyl and Anti-Wick quantization. ... More

Shifted set families, degree sequences, and plethysmOct 26 2006Jan 10 2008We study, in three parts, degree sequences of k-families (or k-uniform hypergraphs) and shifted k-families. The first part collects for the first time in one place, various implications such as: Threshold implies Uniquely Realizable implies Degree-Maximal ... More

An l1-Oracle Inequality for the LassoJul 27 2010The Lasso has attracted the attention of many authors these last years. While many efforts have been made to prove that the Lasso behaves like a variable selection procedure at the price of strong (though unavoidable) assumptions on the geometric structure ... More

Learning directed acyclic graphs based on sparsest permutationsJul 01 2013Feb 24 2014We consider the problem of learning a Bayesian network or directed acyclic graph (DAG) model from observational data. A number of constraint-based, score-based and hybrid algorithms have been developed for this purpose. For constraint-based methods, statistical ... More

Transient Thermal Behaviour in a Model of Linear Friction WeldingFeb 12 2016We derive a non-local model for the evolution of temperature in workpieces being joined by linear friction welding. The non-locality arises through the velocity being fixed by the temperature gradient at the weld. Short- and long-time behaviours are considered. ... More

Extremal theory of locally sparse multigraphsAug 31 2016An $(n,s,q)$-graph is an $n$-vertex multigraph where every set of $s$ vertices spans at most $q$ edges. In this paper, we determine the maximum product of the edge multiplicities in $(n,s,q)$-graphs if the congruence class of $q$ modulo ${s\choose 2}$ ... More

To Motivate Social Grouping in Wireless NetworksNov 05 2015Jun 21 2016We consider a group of neighboring smartphone users who are roughly at the same time interested in the same network content, called common interests. However, ever-increasing data traffic challenges the limited capacity of base-stations (BSs) in wireless ... More

[alpha/Fe] in the thin and the thick disk towards an automatic parametrization of stellar spectraNov 10 2004We test an automatic procedure to measure [Fe/H] and [alpha/Fe] on high resolution spectra. The test sample is the intersection of the ELODIE library and a catalogue of 830 stars having well determined abundances.

Density Evolution for SUDOKU Codes on the Erasure ChannelJul 16 2014Codes based on SUDOKU puzzles are discussed, and belief propagation decoding introduced for the erasure channel. Despite the non-linearity of the code constraints, it is argued that density evolution can be used to analyse code performance due to the ... More

Evaluating Parsing Schemes with Entropy IndicatorsSep 22 1997This paper introduces an objective metric for evaluating a parsing scheme. It is based on Shannon's original work with letter sequences, which can be extended to part-of-speech tag sequences. It is shown that this regular language is an inadequate model ... More

Vortices and black holes in dilatonic gravityJun 25 1999Apr 11 2000We study analytically black holes pierced by a thin vortex in dilatonic gravity for an arbitrary coupling of the vortex to the dilaton in an arbitrary frame. We show that the horizon of the charged black hole supports the long-range fields of the Nielsen-Olesen ... More

Part-products of $S$-restricted integer compositionsMar 11 2012If $S$ is a cofinite set of positive integers, an "$S$-restricted composition of $n$" is a sequence of elements of $S$, denoted $\vec{\lambda}=(\lambda_1,\lambda_2,...)$, whose sum is $n$. For uniform random $S$-restricted compositions, the random variable ... More

Star Formation and AGN Activity in Interacting Galaxies: A Near-UV PerspectiveOct 18 2013We study nearby galaxies in close pairs to study the key factors affecting star formation and AGN activity triggered during galaxy interactions. Close pairs are selected from the Sloan Digital Sky Survey assuming a projected separation of $<$30kpc and ... More

Baker-Akhiezer spinor kernel and tau-functions on moduli spaces of meromorphic differentialsJul 01 2013Jan 16 2014In this paper we study Baker-Akhiezer spinor kernel on moduli spaces of meromorphic differentials on Riemann surfaces. We introduce the Baker-Akhiezer tau-function which is related to both Bergman tau-function (which was studied before in the context ... More

Cloud computing and hyperbolic Voronoi diagrams on the sphereMar 13 2012In this work we study the minimization problem for the total distance in a cloud computing network on the sphere. We give a solution to this problem in terms of hyperbolic Voronoi diagrams on the sphere. We present results of computer simulations illustrating ... More

Homodyne detection and optical parametric amplification: a classical approach applied to proposed "loophole-free" Bell testsDec 17 2005Recent proposed ``loophole-free'' Bell tests are discussed in the light of classical models for the relevant features of optical parametric amplification and homodyne detection. The Bell tests themselves are uncontroversial: there are no obvious loopholes ... More

Timing, ``Accidentals'' and Other Artifacts in EPR ExperimentsNov 20 1997Nov 25 1997Subtraction of ``accidentals'' in Einstein-Podolsky-Rosen experiments frequently changes results compatible with local realism into ones that appear to demonstrate non-locality. The validity of the procedure depends on the unproven assumption of the independence ... More

Discrete metric spaces: structure, enumeration, and $0$-$1$ lawsFeb 04 2015Feb 09 2015Fix an integer $r\geq 3$. We consider metric spaces on $n$ points such that the distance between any two points lies in $\{1,..., r\}$. Our main result describes their approximate structure for large $n$. As a consequence, we show that the number of these ... More

Spacetime structure of the global vortexAug 05 2002Aug 25 2002We analyse the spacetime structure of the global vortex and its maximal analytic extension in an arbitrary number of spacetime dimensions. We find that the vortex compactifies space on the scale of the Hubble expansion of its worldvolume, in a manner ... More

Cosmology in Brans-Dicke theory with a scalar potentialNov 27 1996We consider the general behaviour of cosmologies in Brans-Dicke theory where the dilaton is self-interacting via a potential $V(\Phi)$. We show that the general radiation universe is a two-dimensional dynamical system whereas the dust or false vacuum ... More

Endotrivial modules for the sporadic simple groups and their coversFeb 20 2015Mar 25 2015In a step towards the classification of endotrivial modules for quasi-simple groups, we investigate endotrivial modules for the sporadic simple groups and their covers. A main outcome of our study is the existence of torsion endotrivial modules with dimension ... More

Corrections to Wigner type phase space methodsMar 12 2014Oct 10 2014Over decades, the time evolution of Wigner functions along classical Hamiltonian flows has been used for approximating key signatures of molecular quantum systems. Such approximations are for example the Wigner phase space method, the linearized semiclassical ... More

The Stokes phenomenon in the confluence of the hypergeometric equation using Riccati equationJun 12 2007Nov 01 2007In this paper we study the confluence of two regular singular points of the hypergeometric equation into an irregular one. We study the consequence of the divergence of solutions at the irregular singular point for the unfolded system. Our study covers ... More

Hagedorn wavepackets in time-frequency and phase spaceMar 21 2013Mar 12 2014The Hermite functions are an orthonormalbasis of the space of square integrable functions with favourable approximation properties. Allowing for a flexible localization in position and momentum, the Hagedorn wavepackets generalize the Hermite functions ... More

Multivariate Gaussians, Semidefinite Matrix Completion, and Convex Algebraic GeometryJun 18 2009We study multivariate normal models that are described by linear constraints on the inverse of the covariance matrix. Maximum likelihood estimation for such models leads to the problem of maximizing the determinant function over a spectrahedron, and to ... More

Delta-33 medium mass modification and pion spectraJul 13 2005May 21 2007We study the pi+- spectra obtained in 2,4,6,8 A GeV Au-Au collisions within the thermal model. We find that the main features of the data can be well described after we include the pions from the decay of the Delta-resonance with medium mass modification. ... More

Direct reconstruction of dark energyFeb 26 2010May 04 2010An important issue in cosmology is reconstructing the effective dark energy equation of state directly from observations. With so few physically motivated models, future dark energy studies cannot only be based on constraining a dark energy parameter ... More

3D Ising Nonuniversality: a Monte Carlo studyJan 29 2005We investigate as a member of the Ising universality class the Next-Nearest Neighbour Ising model without external field on a simple cubic lattice by using the Monte Carlo Metropolis Algorithm. The Binder cumulant and the susceptibility ratio, which should ... More

A database of high and medium-resolution stellar spectraJan 22 2001We present a database of 908 spectra of 709 stars obtained with the ELODIE spectrograph at Observatoire de Haute-Provence. 52 orders of the echelle spectra have been carefully fitted together to provide continuous, high-resolution spectra in the wavelength ... More

A fast partial parse of natural language sentences using a connectionist methodMar 22 1995The pattern matching capabilities of neural networks can be used to locate syntactic constituents of natural language. This paper describes a fully automated hybrid system, using neural nets operating within a grammatic framework. It addresses the representation ... More

Elemental abundances as a function of kinematics in the Milky Way's diskJan 20 2006We present the results of our investigation of three samples kinematically representative of the thin and thick disks and the Hercules stream using the catalogue of Soubiran & Girard (2005). We have observed abundance trends and age distribution of each ... More

The Second Quantized Quantum Turing Machine and Kolmogorov ComplexityJun 30 2005Apr 05 2008The Kolmogorov complexity of a physical state is the minimal physical resources required to reproduce that state. We define a second quantized quantum Turing machine and use it to define second quantized Kolmogorov complexity. There are two advantages ... More

Modernity of Halphen's variations on a theme of MongeFeb 14 2016We construct a Z_3-slice to the natural action of PGL(V) on the variety of smooth arcs in the projective space P(V).

Rotational Invariance, Phase Relationships and the Quantum Entanglement IllusionDec 16 1999Another Bell test "loophole" - imperfect rotational invariance - is explored, and novel realist ideas on parametric down-conversion as used in recent "quantum entanglement" experiments are presented. The usual quantum theory of entangled systems assumes ... More

Timing and Other Artifacts in EPR ExperimentsApr 29 1997Re-evaluation of the evidence (some of it unpublished) shows that experimenters conducting Einstein-Podolsky-Bohm (EPR) experiments may have been deceived by various pre-conceptions and artifacts. False or unproven assumptions were made regarding, in ... More

Subtraction of ``accidentals'' and the validity of Bell testsMar 18 1999Apr 21 1999In some key Bell experiments, including two of the well-known ones by Alain Aspect, 1981-2, it is only after the subtraction of ``accidentals'' from the coincidence counts that we get violations of Bell tests. The data adjustment, producing increases ... More

Design of Cooperative Processes in a Customer-Supplier Relationship: An Approach Based on Simulation and Decision TheoryOct 22 2008Performance improvement in supply chains, taking into account customer demand in the tactical planning process is essential. It is more and more difficult for the customers to ensure a certain level of demand over a medium term horizon as their own customers ... More

Limits of limit sets IJul 05 2011We show that for a strongly convergent sequence of geometrically finite Kleinian groups with geometrically finite limit, the Cannon-Thurston maps of limit sets converge uniformly. If however the algebraic and geometric limits differ, as in the well known ... More

Quasi-classical description of molecular dynamics based on Egorov's theoremMay 28 2014Oct 23 2014Egorov's theorem on the classical propagation of quantum observables is related to prominent quasi-classical descriptions of quantum molecuar dynamics as the linearized semiclassical initial value representation (LSC-IVR), the Wigner phase space method ... More

Model theoretic properties of the Urysohn sphereJan 09 2014Apr 08 2015We characterize model theoretic properties of the Urysohn sphere as a metric structure in continuous logic. In particular, our first main result shows that the theory of the Urysohn sphere is $\text{SOP}_n$ for all $n\geq 3$, but does not have the fully ... More

A Simple Method To Test For Energy-Dependent Dispersion In High Energy Light Curves Of Astrophysical SourcesOct 24 2012We present a method of testing for the presence of energy dependent dispersion in transient features of a light curve. It is based on minimising the Kolmogorov distance between two cumulative event distribution functions. The unbinned and non-parametric ... More

An unbinned test for Quantum Gravity effects in high-energy light-curvesJun 29 2009Some models of quantum gravity can predict observable effects on the propagation of light: most notably an energy dependent dispersion, where the speed of light is seen to vary with the energy of the photon. As quantum gravity effects should appear at ... More

Cônes nilpotents des super algèbres de Lie orthosymplectiquesOct 13 2009We look at the odd nilpotent orbits of osp(2n+1,2n), giving a combinatorial interpretation which enables us, via the square map, to explain the link with even nilpotent orbits. We then study the closure ordering of the odd nilpotent orbits. Finally, we ... More

A litmus test for LambdaJul 28 2008The critical issue in cosmology today lies in determining if the cosmological constant is the underlying ingredient of dark energy. Our profound lack of understanding of the physics of dark energy places severe constrains on our ability to say anything ... More

Bringing Science into Schools through Astronomy. Project ASTRO, TucsonAug 19 2005We report our experience in bringing science into US and French classrooms. We participated in the US scientific educational program Project ASTRO. It is based on a partnership between a school teacher and an astronomer. They together design and realize ... More

Spin equilibrium in strongly-magnetized accreting starsSep 27 2016The spin rate of a strongly-magnetized accreting star is regulated by the interaction between the star's magnetic field and the accreting gas. These systems are often hypothesized to be in `spin equilibrium' with their surrounding accretion flows such ... More

Measuring Portfolio DiversificationFeb 23 2011In the market place, diversification reduces risk and provides protection against extreme events by ensuring that one is not overly exposed to individual occurrences. We argue that diversification is best measured by characteristics of the combined portfolio ... More

International Collaboration in Science and the Formation of a Core GroupNov 07 2009International collaboration as measured by co-authorship relations on refereed papers grew linearly from 1990 to 2005 in terms of the number of papers, but exponentially in terms of the number of international addresses. This confirms Persson et al.'s ... More