Results for "Didier Schwab"

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Comparison of Global Algorithms in Word Sense DisambiguationApr 07 2017This article compares four probabilistic algorithms (global algorithms) for Word Sense Disambiguation (WSD) in terms of the number of scorer calls (local algo- rithm) and the F1 score as determined by a gold-standard scorer. Two algorithms come from the ... More
Improving the Coverage and the Generalization Ability of Neural Word Sense Disambiguation through Hypernymy and Hyponymy RelationshipsNov 02 2018In Word Sense Disambiguation (WSD), the predominant approach generally involves a supervised system trained on sense annotated corpora. The limited quantity of such corpora however restricts the coverage and the performance of these systems. In this article, ... More
Sense Vocabulary Compression through the Semantic Knowledge of WordNet for Neural Word Sense DisambiguationMay 14 2019In this article, we tackle the issue of the limited quantity of manually sense annotated corpora for the task of word sense disambiguation, by exploiting the semantic relationships between senses such as synonymy, hypernymy and hyponymy, in order to compress ... More
Enhancing Translation Language Models with Word Embedding for Information RetrievalJan 11 2018In this paper, we explore the usage of Word Embedding semantic resources for Information Retrieval (IR) task. This embedding, produced by a shallow neural network, have been shown to catch semantic similarities between words (Mikolov et al., 2013). Hence, ... More
On the Category of Partial BijectionsMar 05 2009Categories of partial functions have become increasingly important principally because of their applications in theoretical computer science. In this note we prove that the category of partial bijections between sets as an inverse-Baer*-category with ... More
Persistent current in metals with a large dephasing rateMay 30 2000In a weakly disordered metal electron interactions are responsible for both decoherence of the quasi-particles as well as for quantum corrections to thermodynamic properties. We consider electrons which are interacting with two-level-systems. We show ... More
Image and Transfer FunctionsMay 12 2009We describe three transfer functors P, P', P" of an inverse exact category which arise from three transfer functions. We concentrate on some of the basic results which emerge from the theory of projections in inverse exact categories.
Évaluation et consolidation d'un réseau lexical via un outil pour retrouver le mot sur le bout de la langueJan 20 2012Since September 2007, a large scale lexical network for French is under construction through methods based on some kind of popular consensus by means of games (JeuxDeMots project). Human intervention can be considered as marginal. It is limited to corrections, ... More
Système de traduction automatique statistique Anglais-ArabeFeb 06 2018Machine translation (MT) is the process of translating text written in a source language into text in a target language. In this article, we present our English-Arabic statistical machine translation system. First, we present the general process for setting ... More
Deep Investigation of Cross-Language Plagiarism Detection MethodsMay 24 2017This paper is a deep investigation of cross-language plagiarism detection methods on a new recently introduced open dataset, which contains parallel and comparable collections of documents with multiple characteristics (different genres, languages and ... More
CompiLIG at SemEval-2017 Task 1: Cross-Language Plagiarism Detection Methods for Semantic Textual SimilarityApr 05 2017We present our submitted systems for Semantic Textual Similarity (STS) Track 4 at SemEval-2017. Given a pair of Spanish-English sentences, each system must estimate their semantic similarity by a score between 0 and 5. In our submission, we use syntax-based, ... More
Coherent transport in disordered metals out of equilibriumJun 13 2001We derive a formula for the quantum corrections to the electrical current for a metal out of equilibrium. In the limit of linear current-voltage characteristics our formula reproduces the well known Altshuler-Aronov correction to the conductivity of a ... More
Quasiclassical theory of charge transport in disordered interacting electron systemsOct 01 2003We consider the corrections to the Boltzmann theory of electrical transport arising from the Coulomb interaction in disordered conductors. In this article the theory is formulated in terms of quasiclassical Green's functions. We demonstrate that the formalism ... More
A Partial Order on Bipartite Graphs with n VerticesJun 04 2009The paper examines a partial order on bipartite graphs (X1, X2, E) with n vertices, X1UX2={1,2,...,n}. This partial order is a natural partial order of subobjects of an object in a triangular category with bipartite graphs as morphisms.
Landau levels in a topological insulatorJul 05 2011Two recent experiments successfully observed Landau levels in the tunneling spectra of the topological insulator Bi2Se3. To mimic the influence of a scanning tunneling microscope tip on the Landau levels we solve the two-dimensional Dirac equation in ... More
Compressive sensing Petrov-Galerkin approximation of high-dimensional parametric operator equationsOct 18 2014Sep 21 2015We analyze the convergence of compressive sensing based sampling techniques for the efficient evaluation of functionals of solutions for a class of high-dimensional, affine-parametric, linear operator equations which depend on possibly infinitely many ... More
Quasiclassical theory of electronic transport in mesoscopic systems: Luttinger liquids revisitedSep 21 2006Dec 13 2006The method of the quasiclassical Green's function is used to determine the equilibrium properties of one-dimensional (1D) interacting Fermi systems, in particular, the bulk and the local (near a hard wall) density of states. While this is a novel approach ... More
Andreev tunnelling in quantum dots: A slave-boson approachJun 05 1998We study a strongly interacting quantum dot connected to a normal and to a superconducting lead. By means of the slave-boson technique we investigate the low temperature regime and discuss electrical transport through the dot. We find that the zero bias ... More
Tuning the Spin Hall Effect in a Two-Dimensional Electron GasMay 08 2009We provide a theoretical framework for the electric field control of the electron spin in systems with diffusive electron motion. The approach is valid in the experimentally important case where both intrinsic and extrinsic spin-orbit interaction in a ... More
Magnetoconductance of a two-dimensional metal in the presence of spin-orbit couplingOct 22 2001We show that in the metallic phase of a two dimensional electron gas the spin-orbit coupling due to structure inversion asymmetry leads to a characteristic anisotropy in the magnetoconductance. Within the assumption that the metallic phase can be described ... More
Andreev Tunneling in Strongly Interacting Quantum DotsDec 17 1998Apr 20 1999We review recent work on resonant Andreev tunneling through a strongly interacting quantum dot connected to a normal and to a superconducting lead. We derive a general expression for the current flowing in the structure and discuss the linear and non-linear ... More
Spin-Hall effect in a disordered 2D electron-systemAug 11 2004We calculate the spin-Hall conductivity for a two-dimensional electron gas within the self-consistent Born approximation, varying the strength and type of disorder. In the weak disorder limit we find both analytically and numerically a vanishing spin-Hall ... More
Interplay of intrinsic and extrinsic mechanisms to the spin Hall effect in a two-dimensional electron gasSep 10 2009In order to describe correctly the interplay of extrinsic and intrinsic spin-orbit mechanisms to the spin Hall effect, it is necessary to consider different sources of spin relaxation. We take into account the spin relaxation time $\tau_{DP}$ due to the ... More
Persistent current induced by magnetic impuritiesFeb 05 1997We calculate the average persistent current in a normal conducting, mesoscopic ring in the diffusive regime. In the presence of magnetic impurities, a contribution to the persistent current is identified, which is related to fluctuations in the electron ... More
Characterizations of Some Class of Formal Power Series via MÖbius Categories of Full Binomial TypeJan 18 2005In some previous papers we have obtained characterizations (we called them characterizations of Lambek-Carlitz type) of some class of formal power series. Now, we discuss, investigate and compare these results from a categorial point of view.
kHz QPOs from the 2000 and 2010 X-ray transients located in the globular cluster Terzan 5: EXO1745-248 and IGR J17480-2446May 02 2012EXO1745-248 is a transient neutron star low-mass X-ray binary located in the globular cluster Terzan 5. It was in outburst in 2000 and displayed during one Rossi X-ray Timing Explorer observation a highly coherent quasi-periodic oscillation (QPO) at frequencies ... More
Properties of holons in the Quantum Dimer ModelNov 14 2007Jan 22 2008I introduce a doped two-dimensional quantum dimer model describing a doped Mott insulator and retaining the original Fermi statistics of the electrons. This model shows a rich phase diagram including a d-wave hole-pair unconventional superconductor at ... More
Out-of-equilibrium Correlated Systems : Bipartite Entanglement as a Probe of ThermalizationNov 09 2010Apr 18 2011Thermalization play a central role in out-of-equilibrium physics of ultracold atoms or electronic transport phenomena. On the other hand, entanglement concepts have proven to be extremely useful to investigate quantum phases of matter. Here, it is argued ... More
Nurturing Breakthroughs: Lessons from Complexity TheoryJun 13 2007A general theory of innovation and progress in human society is outlined, based on the combat between two opposite forces (conservatism/inertia and speculative herding "bubble" behavior). We contend that human affairs are characterized by ubiquitous ``bubbles'', ... More
Detecting rigid convexity of bivariate polynomialsJan 23 2008Given a polynomial $x \in {\mathbb R}^n \mapsto p(x)$ in $n=2$ variables, a symbolic-numerical algorithm is first described for detecting whether the connected component of the plane sublevel set ${\mathcal P} = \{x : p(x) \geq 0\}$ containing the origin ... More
Direct evidence of negative refraction at media with negative ε and μNov 15 2002We analyze wave scattering by an interface between a positive refractive index medium and a Left-Handed Material. We show that the negative refraction effect can be deduced directly from Maxwell equations, without references to causality or losses.
Comment on ''Photonic Band Gaps: Noncommuting limit and the 'Acoustic Band'''Apr 25 2001This comment concerns the homogenization of 2D dielectric photonic crystals, and the fact that the limits $k\to 0$ ($k$ is the Bloch vector) and $\epsilon \to +\infty $ do not commute for $p$-polarized waves
Entanglement spectra of quantum Heisenberg laddersMay 12 2010Jun 29 2010Bipartite entanglement measures are fantastic tools to investigate quantum phases of correlated electrons. Here, I analyze the entanglement spectrum of **gapped** two-leg quantum Heisenberg ladders on a periodic ribbon partitioned into two identical periodic ... More
Dragon-Kings, Black Swans and the Prediction of CrisesJul 24 2009We develop the concept of ``dragon-kings'' corresponding to meaningful outliers, which are found to coexist with power laws in the distributions of event sizes under a broad range of conditions in a large variety of systems. These dragon-kings reveal ... More
On Cayley graphs of basic algebraic structuresMar 15 2019We present simple graph-theoretic characterizations of Cayley graphs for monoids, semigroups and groups. We extend these characterizations to commutative monoids, semilattices, and abelian groups.
Coherent transport in disordered metals: zero dimensional limitSep 02 2002We consider non-equilibrium transport in disordered conductors. We calculate the interaction correction to the current for a short wire connected to electron reservoirs by resistive interfaces. In the absence of charging effects we find a universal current-voltage-characteristics. ... More
Persistent Currents versus Phase Breaking in Mesoscopic Metallic SamplesJan 21 2002Persistent currents in mesoscopic normal metal rings represent, even a decade after their first experimental observation, a challenge to both, theorists and experimentalists. After giving a brief review of the existing -- experimental and theoretical ... More
Aleksandrov-Bakelman-Pucci Type Estimates For Integro-Differential EquationsDec 31 2010Apr 04 2012In this work we provide an Aleksandrov-Bakelman-Pucci type estimate for a certain class of fully nonlinear elliptic integro-differential equations, the proof of which relies on an appropriate generalization of the convex envelope to a nonlocal, fractional-order ... More
Mixing via Thermocompositional Convection in Hybrid C/O/Ne White DwarfsOct 16 2018Mar 18 2019Convective overshooting in super asymptotic giant branch stars has been suggested to lead to the formation of hybrid white dwarfs with carbon-oxygen cores and oxygen-neon mantles. As the white dwarf cools, this core-mantle configuration becomes convectively ... More
Stochastic Homogenization for Some Nonlinear Integro-Differential EquationsJan 31 2011Sep 07 2012In this note we extend to the random, stationary ergodic setting previous results of periodic homogenization for a particular family of nonlinear nonlocal "elliptic" equations with oscillatory coefficients. Such equations include, but are not limited ... More
Nonlocal adiabatic theory. II. Nonlinear frequency shift of an electron plasma wave in a multidimensional inhomogeneous plasmaJun 12 2017Sep 15 2017In this article, we provide a general derivation of the nonlinear frequency shift, $\delta \omega$, for a sinusoidal electron plasma wave (EPW) that varies slowly enough for the results derived in the companion paper, on the action distribution function, ... More
Envelope equation for the linear and nonlinear propagation of an electron plasma wave, including the effects of Landau damping, trapping, plasma inhomogeneity, and the change in the state of waveJul 20 2016Sep 13 2016This paper addresses the linear and nonlinear three-dimensional propagation of an electron wave in a collisionless plasma that may be inhomogeneous, nonstationary, anisotropic and even weakly magnetized. The wave amplitude, together with any hydrodynamic ... More
Maximal generalization of Baum-Katz theorem and optimality of sequential testsOct 03 2005Baum-Katz theorem asserts that the Cesaro means of i.i.d. increments distributed like X r-converge if and only if |X|^{r+1} is integrable. We generalize this, and we unify other results, by proving that the following equivalence holds, if and only if ... More
Some control design experiments with HIFOOSep 01 2006A new MATLAB package called HIFOO was recently proposed for H-infinity fixed-order controller design. This document illustrates how some standard controller design examples can be solved with this software.
Confidence intervals for nonhomogeneous branching processes and polymerase chain reactionsMar 29 2005We extend in two directions our previous results about the sampling and the empirical measures of immortal branching Markov processes. Direct applications to molecular biology are rigorous estimates of the mutation rates of polymerase chain reactions ... More
Structural characterization of Cayley graphsSep 27 2016We show that the directed labelled Cayley graphs coincide with the rooted deterministic vertex-transitive simple graphs. The Cayley graphs are also the strongly connected deterministic simple graphs of which all vertices have the same cycle language, ... More
Asymptotics of iterated branching processesOct 03 2005We study the iterated Galton-Watson process (IGW), possibly with thinning, introduced by Gawe{\l}and Kimmel to model the number of repeats of DNA triplets during some genetic disorders. If the process involves some thinning, then extinction and explosion ... More
Harmonic moments of non homogeneous branching processesOct 03 2005We study the harmonic moments of Galton-Watson processes, possibly non homogeneous, with positive values. Good estimates of these are needed to compute unbiased estimators for non canonical branching Markov processes, which occur, for instance, in the ... More
Invariance principle for the coverage rate of genomic physical mappingsOct 03 2005We study some stochastic models of physical mapping of genomic sequences. Our starting point is a global construction of the process of the clones and of the process of the anchors which are used to map the sequence. This yields explicit formulas for ... More
Asymptotics of posteriors for binary branching processesJun 06 2008We compute the posterior distributions of the initial population and parameter of binary branching processes, in the limit of a large number of generations. We compare this Bayesian procedure with a more na\"ive one, based on hitting times of some random ... More
Optimal pattern matching algorithmsApr 28 2016May 02 2016We study a class of finite state machines, called \defi{$w$-matching machines}, which yield to simulate the behavior of pattern matching algorithms while searching for a pattern $w$. They can be used to compute the asymptotic speed, i.e. the limit of ... More
Harmonic continuous-time branching momentsNov 02 2005Feb 14 2007We show that the mean inverse populations of nondecreasing, square integrable, continuous-time branching processes decrease to zero like the inverse of their mean population if and only if the initial population $k$ is greater than a first threshold $m_1\ge1$. ... More
On the Cauchy problem for higher-order nonlinear dispersive equationsAug 27 2007We study a class of higher-order KdV equations. We show that the associated initial value problem is well posed in weighted Besov and Sobolev spaces for small initial data. We also prove ill-posedness results when in H^s(\R), for any real s.
On convexity of the frequency response of a stable polynomialSep 07 2007In the complex plane, the frequency response of a univariate polynomial is the set of values taken by the polynomial when evaluated along the imaginary axis. This is an algebraic curve partitioning the plane into several connected components. In this ... More
Quantum Measurement of a Coupled Nanomechanical Resonator -- Cooper-Pair Box SystemJan 15 2003Jul 31 2003We show two effects as a result of considering the second-order correction to the spectrum of a nanomechanical resonator electrostatically coupled to a Cooper-pair box. The spectrum of the Cooper-pair box is modified in a way which depends on the Fock ... More
The deterministic information bottleneckApr 01 2016Dec 19 2016Lossy compression and clustering fundamentally involve a decision about what features are relevant and which are not. The information bottleneck method (IB) by Tishby, Pereira, and Bialek formalized this notion as an information-theoretic optimization ... More
An exact mapping between the Variational Renormalization Group and Deep LearningOct 14 2014Deep learning is a broad set of techniques that uses multiple layers of representation to automatically learn relevant features directly from structured data. Recently, such techniques have yielded record-breaking results on a diverse set of difficult ... More
The deterministic information bottleneckApr 01 2016Compression fundamentally involves a decision about what is relevant and what is not. The information bottleneck method (IB) by Tishby, Pereira, and Bialek formalized this notion as an information-theoretic optimization problem and proposed an optimal ... More
Wait for it: Post-supernova winds driven by delayed radioactive decaysOct 20 2016In most astrophysical situations, the radioactive decay of 56Ni to 56Co occurs via electron capture with a fixed half-life of 6.1 days. However, this decay rate is significantly slowed when the nuclei are fully ionized because K-shell electrons are unavailable ... More
Min-max formulas for nonlocal elliptic operatorsJun 27 2016In this work, we give a characterization of Lipschitz operators on spaces of $C^2(M)$ functions (also $C^{1,1}$, $C^{1,\gamma}$, $C^1$, $C^\gamma$) that obey the global comparison property-- i.e. those that preserve the global ordering of input functions ... More
Regularity results for nonlocal parabolic equationsMay 23 2013Aug 28 2013We survey recent regularity results for parabolic equations involving nonlocal operators like the fractional Laplacian. We extend the results of Felsinger-Kassmann (2013) and obtain regularity estimates for nonlocal operators with kernels not being absolutely ... More
Residual Carbon in Oxygen-Neon White Dwarfs and its Implications for Accretion-Induced CollapseOct 30 2018Jan 16 2019We explore the effects of the residual $\mathrm{^{12}C}$ present in oxygen-neon white dwarfs (ONe WDs) on their evolution towards accretion-induced collapse (AIC). We produce a set of ONe WD models using MESA and illustrate how the amount and location ... More
Sparse Deterministic Approximation of Bayesian Inverse ProblemsMar 23 2011Feb 08 2012We present a parametric deterministic formulation of Bayesian inverse problems with input parameter from infinite dimensional, separable Banach spaces. In this formulation, the forward problems are parametric, deterministic elliptic partial differential ... More
Regularity for parabolic integro-differential equations with very irregular kernelsDec 11 2014We prove H\"older regularity for a general class of parabolic integro-differential equations, which (strictly) includes many previous results. We present a proof which avoids the use of a convex envelop as well as give a new covering argument which is ... More
The Computation of the Möbius Function of a Möbius CategoryOct 29 2012The paper presents some results for reducing the computation of the M\"obius functon of a M\"obius category that arises from a combinatorial inverse semigroup to that of locally finite partially ordered sets. We illustrate the computation of the M\"obius ... More
Practical Model-Based Diagnosis with Qualitative Possibilistic UncertaintyFeb 20 2013An approach to fault isolation that exploits vastly incomplete models is presented. It relies on separate descriptions of each component behavior, together with the links between them, which enables focusing of the reasoning to the relevant part of the ... More
Ultra-high Q Acoustic Resonance in Superfluid 4HeJul 26 2016We report the measurement of the acoustic quality factor of a gram-scale, kilo-hertz frequency superfluid resonator, detected through the parametric coupling to a superconducting niobium microwave cavity. For temperature between 400mK and 50mK, we observe ... More
Flavor Changing Neutral Current Effects and CP Violation in the Minimal 3-3-1 ModelFeb 16 2007Jun 15 2007We investigate in detail the flavor structure of the minimal 331 model and its implications for several flavor changing neutral current (FCNC) processes. In this model, where the weak SU(2)_L gauge group of the Standard Model is extended to a SU(3)_L, ... More
On localization effects in underdoped cupratesDec 22 1998We comment on transport experiments in underdoped LaSrCuO in the non-superconducting phase. The temperature dependence of the resistance strongly resembles what is expected from standard localization theory. However this theory fails, when comparing with ... More
Residual Local Supersymmetry and the Soft GravitinoDec 08 2015We show that there exists an infinite tower of fermionic symmetries in pure $d=4$, $\mathcal{N}=1$ supergravity on an asymptotically flat background. The Ward identities associated with these symmetries are equivalent to the soft limit of the gravitino ... More
BMS, String Theory, and Soft TheoremsJun 18 2015We study the action of the BMS group in critical, bosonic string theory living on a target space of the form $\mathbb{M}^{d}\times C$. Here $M^{d}$ is $d$-dimensional (asymptotically) flat spacetime and $C$ is an arbitrary compactification. We provide ... More
Evolution of Helium Star - White Dwarf Binaries Leading up to Thermonuclear SupernovaeJan 14 2019May 07 2019We perform binary evolution calculations on helium star - carbon-oxygen white dwarf (CO WD) binaries using the stellar evolution code MESA. This single degenerate channel may contribute significantly to thermonuclear supernovae at short delay times. We ... More
Deep Null Space Learning for Inverse Problems: Convergence Analysis and RatesJun 15 2018Aug 15 2018Recently, deep learning based methods appeared as a new paradigm for solving inverse problems. These methods empirically show excellent performance but lack of theoretical justification; in particular, no results on the regularization properties are available. ... More
Confinement and critical regime in doped frustrated quasi-one dimensional magnetsFeb 15 2005Ground state and finite temperature properties of a system of coupled frustrated and/or dimerized spin-1/2 chains modeling e.g. the CuGeO$_3$ compound are reviewed. Special emphasis is put on the investigation of the role of impurity doping. A c hain-mean ... More
Spurious trend switching phenomena in financial marketsDec 16 2011The observation of power laws in the time to extrema of volatility, volume and intertrade times, from milliseconds to years, are shown to result straightforwardly from the selection of biased statistical subsets of realizations in otherwise featureless ... More
Semiclassical results in the linear response theoryNov 21 2002We consider a quantum system of non-interacting fermions at temperature T, in the framework of linear response theory. We show that semiclassical theory is an appropriate framework to describe some of their thermodynamic properties, in particular through ... More
Quadratic Quantum Hamiltonians revisitedSep 13 2005Time dependent quadratic Hamiltonians are well known as well in classical mechanics and in quantum mechanics. In particular for them the correspondance between classical and quantum mechanics is exact. But explicit formulas are non trivial (like the Mehler ... More
Modified Shallow Water Equations for significantly varying seabedsFeb 29 2012Apr 27 2016In the present study, we propose a modified version of the Nonlinear Shallow Water Equations (Saint-Venant or NSWE) for irrotational surface waves in the case when the bottom undergoes some significant variations in space and time. The model is derived ... More
Dynamical Diagnosis and Solutions for Resilient Natural and Social SystemsNov 08 2012The concept of resilience embodies the quest towards the ability to sustain shocks, to suffer from these shocks as little as possible, for the shortest time possible, and to recover with the full functionalities that existed before the perturbation. We ... More
Bilinear Strichartz estimates for the Zakharov-Kuznetsov equation and applicationsFeb 12 2013Mar 01 2013This article is concerned with the Zakharov-Kuznetsov equation {equation} \label{ZK0} \partial_tu+\partial_x\Delta u+u\partial_xu=0 . {equation} We prove that the associated initial value problem is locally well-posed in $H^s(\mathbb R^2)$ for $s>\frac12$ ... More
GADT meet SubtypingOct 22 2012While generalized abstract datatypes (GADT) are now considered well-understood, adding them to a language with a notion of subtyping comes with a few surprises. What does it mean for a GADT parameter to be covariant? The answer turns out to be quite subtle. ... More
Convex inner approximations of nonconvex semialgebraic sets applied to fixed-order controller designApr 14 2011Jan 10 2012We describe an elementary algorithm to build convex inner approximations of nonconvex sets. Both input and output sets are basic semialgebraic sets given as lists of defining multivariate polynomials. Even though no optimality guarantees can be given ... More
The Fundamental Plane of Early-Type Galaxies as a Confounding CorrelationJun 16 2011Early-type galaxies are characterized by many scaling relations. One of them, the so-called fundamental plane is a relatively tight correlation between three variables, and has resisted a clear physical understanding despite many years of intensive research. ... More
The Back and Forth Nudging algorithm for data assimilation problems: theoretical results on transport equationsSep 28 2008In this paper, we consider the back and forth nudging algorithm that has been introduced for data assimilation purposes. It consists of iteratively and alternately solving forward and backward in time the model equation, with a feedback term to the observations. ... More
How to grow a bubble: A model of myopic adapting agentsJun 18 2008Nov 11 2010We present a simple agent-based model to study the development of a bubble and the consequential crash and investigate how their proximate triggering factor might relate to their fundamental mechanism, and vice versa. Our agents invest according to their ... More
Extragalactic Objects and Next Generation InterferometersDec 20 2007The most obvious extragalactic targets for optical/infrared interferometers are Active Galactic Nuclei. In this document, I try to overview other topics that could be of interest to studies of galaxies and whether they could be adequate for a next generation ... More
Financial Bubbles, Real Estate bubbles, Derivative Bubbles, and the Financial and Economic CrisisMay 02 2009The financial crisis of 2008, which started with an initially well-defined epicenter focused on mortgage backed securities (MBS), has been cascading into a global economic recession, whose increasing severity and uncertain duration has led and is continuing ... More
BLINK: a language to view, recognize, classify and manipulate 3D-spacesFeb 02 2007A {\it blink} is a plane graph with its edges being red or green. A {\it 3D-space} or, simply, a {\it space} is a connected, closed and oriented 3-manifold. In this work we explore in details, for the first time, the fact that every blink induces a space ... More
Finite-time singularity in the dynamics of the world population, economic and financial indicesFeb 05 2000Dec 19 2001Contrary to common belief, both the Earth's human population and its economic output have grown faster than exponential, i.e., in a super-Malthusian mode, for most of the known history. These growth rates are compatible with a spontaneous singularity ... More
Large financial crashesApr 15 1997Jun 16 1997We propose that large stock market crashes are analogous to critical points studied in statistical physics with log-periodic correction to scaling. We extend our previous renormalization group model of stock market prices prior to and after crashes [D. ... More
Linear polarization and composition of VLBI jetsJan 11 2002It is shown that linear polarization data can be used to constrain the composition (normal or pair plasma) of pc-scale extragalactic jets. A simple criterion, based on synchrotron and Faraday depolarization properties, is established. It does not depend ... More
A new formalism for the computation of RKKY interaction in aperiodic systemsFeb 03 1999A new formalism to investigate RKKY interaction in aperiodic materials is presented. Particularly useful in the tight-binding scheme, it is used in this paper to probe the role of local environment and long range quasiperiodic potential on this mesoscopic ... More
Modeling the Stock Market prior to large crashesNov 05 1998We propose that the minimal requirements for a model of stock market price fluctuations should comprise time asymmetry, robustness with respect to connectivity between agents, ``bounded rationality'' and a probabilistic description. We also compare extensively ... More
Convergent multiplicative processes repelled from zero: power laws and truncated power lawsSep 07 1996Random multiplicative processes $w_t =\lambda_1 \lambda_2 ... \lambda_t$ (with < \lambda_j > 0 ) lead, in the presence of a boundary constraint, to a distribution $P(w_t)$ in the form of a power law $w_t^{-(1+\mu)}$. We provide a simple and physically ... More
Other-regarding preferences and altruistic punishment: A Darwinian perspectiveAug 21 2009Sep 14 2009This article examines the effect of different other-regarding preference types on the emergence of altruistic punishment behavior from an evolutionary perspective. Our findings corroborate, complement, and interlink the experimental and theoretical literature ... More
Intercluster Correlation in SeismicityJul 29 2003Mega et al.(cond-mat/0212529) proposed to use the ``diffusion entropy'' (DE) method to demonstrate that the distribution of time intervals between a large earthquake (the mainshock of a given seismic sequence) and the next one does not obey Poisson statistics. ... More
Statistical witchhunts: Science, justice & the p-value crisisApr 11 2019We provide accessible insight into the current 'replication crisis' in 'statistical science', by revisiting the old metaphor of 'court trial as hypothesis test'. Inter alia, we define and diagnose harmful statistical witch-hunting both in justice and ... More
Optimal parameters identification and sensitivity study for Abrasive Waterjet Milling modelMay 27 2016In this paper we present the work related to the parameters identification for Abrasive Waterjet Milling (AWJM) model that appears as an ill-posed inverse problem. The necessity of studying this problem comes from the industrial milling applications where ... More
Explicit formulas for a continuous stochastic maturation model. Application to anticancer drug pharmacokinetics/pharmacodynamicsDec 09 2004Apr 02 2008We present a continuous time model of maturation and survival, obtained as the limit of a compartmental evolution model when the number of compartments tends to infinity. We establish in particular an explicit formula for the law of the system output ... More
Persistent Currents in Multichannel Interacting SystemsDec 20 1994Feb 20 1995Persistent currents of disordered multichannel mesoscopic rings of spinless interacting fermions threaded by a magnetic flux are calculated using exact diagonalizations and self-consistent Hartree-Fock methods. The validity of the Hartree-Fock approximation ... More