Results for "Alexandre Bernardino"

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Cleaning tasks knowledge transfer between heterogeneous robots: a deep learning approachMar 13 2019Nowadays, autonomous service robots are becoming an important topic in robotic research. Differently from typical industrial scenarios, with highly controlled environments, service robots must show an additional robustness to task perturbations and changes ... More
Interactive Robot Learning of Gestures, Language and AffordancesNov 24 2017A growing field in robotics and Artificial Intelligence (AI) research is human-robot collaboration, whose target is to enable effective teamwork between humans and robots. However, in many situations human teams are still superior to human-robot teams, ... More
Unscented Bayesian Optimization for Safe Robot GraspingMar 07 2016We address the robot grasp optimization problem of unknown objects considering uncertainty in the input space. Grasping unknown objects can be achieved by using a trial and error exploration strategy. Bayesian optimization is a sample efficient optimization ... More
Beyond the Self: Using Grounded Affordances to Interpret and Describe Others' ActionsFeb 26 2019We propose a developmental approach that allows a robot to interpret and describe the actions of human agents by reusing previous experience. The robot first learns the association between words and object affordances by manipulating the objects in its ... More
Language Bootstrapping: Learning Word Meanings From Perception-Action AssociationNov 27 2017We address the problem of bootstrapping language acquisition for an artificial system similarly to what is observed in experiments with human infants. Our method works by associating meanings to words in manipulation tasks, as a robot interacts with objects ... More
Recurrent Instance SegmentationNov 25 2015Oct 24 2016Instance segmentation is the problem of detecting and delineating each distinct object of interest appearing in an image. Current instance segmentation approaches consist of ensembles of modules that are trained independently of each other, thus missing ... More
An Inequality with Applications to Structured Sparsity and Multitask Dictionary LearningFeb 08 2014Jun 07 2014From concentration inequalities for the suprema of Gaussian or Rademacher processes an inequality is derived. It is applied to sharpen existing and to derive novel bounds on the empirical Rademacher complexities of unit balls in various norms appearing ... More
Applying Domain Randomization to Synthetic Data for Object Category DetectionJul 16 2018Recent advances in deep learning-based object detection techniques have revolutionized their applicability in several fields. However, since these methods rely on unwieldy and large amounts of data, a common practice is to download models pre-trained ... More
Learning at the Ends: From Hand to Tool Affordances in Humanoid RobotsApr 09 2018One of the open challenges in designing robots that operate successfully in the unpredictable human environment is how to make them able to predict what actions they can perform on objects, and what their effects will be, i.e., the ability to perceive ... More
Superconducting qubitsMay 01 2008From a physicist's standpoint, the most interesting part of quantum computing research may well be the possibility to probe the boundary between the quantum and the classical worlds. The more macroscopic are the structures involved, the better. So far, ... More
Using Monoidal Categories in the Transformational Study of Musical Time-Spans and RhythmsMay 30 2013Aug 06 2013Transformational musical theory has so far mainly focused on the study of groups acting on musical chords, one of the most famous example being the action of the dihedral group D24 on the set of major and minor chords. Comparatively less work has been ... More
Spontaneous symmetry breaking and linear effective potentialsMay 05 2012The convexity of a scalar effective potential is a well known property, and, in the situation of spontaneous symmetry breaking, leads to the so-called Maxwell construction, characterised by a flat effective potential between the minima of the bare potential. ... More
Non critical superstring configuration and Minkowski space time in four dimensionsMar 15 2006Feb 21 2007We extend the non-perturbative time-dependent bosonic string action of [3] to a N=1 supersymmetric world sheet action with graviton background, and assume a superpotential, function of the time super coordinate.
Concepts of Renormalization in PhysicsAug 24 2005A non technical introduction to the concept of renormalization is given, with an emphasis on the energy scale dependence in the description of a physical system. We first describe the idea of scale dependence in the study of a ferromagnetic phase transition, ... More
Space-time percolation and detection by mobile nodesAug 31 2011Sep 09 2015Consider the model where nodes are initially distributed as a Poisson point process with intensity $\lambda$ over $\mathbb{R}^d$ and are moving in continuous time according to independent Brownian motions. We assume that nodes are capable of detecting ... More
A counterexample to the Arakelyan ConjectureJul 01 1992A ``self--similar'' example is constructed that shows that a conjecture of N. U. Arakelyan on the order of decrease of deficiencies of an entire function of finite order is not true.
Multifidelity variance reduction for pick-freeze Sobol index estimationMar 25 2013Many mathematical models involve input parameters, which are not precisely known. Global sensitivity analysis aims to identify the parameters whose uncertainty has the largest impact on the variability of a quantity of interest (output of the model). ... More
A berndtsson-Andersson operator solving \bar\partial-equation with W^α-estimates on convex domains of finite typeFeb 22 2010In this article, we use a Berndtsson-Andersson operator and the Bergman metric in order to solve the $\bar\partial$ equation on convex domains of finite type for forms satisifying a Carleson condition and get norm estimates of the solution in term of ... More
Groupes Quantiques d'Interpolation de Langlands de Rang 1Jul 11 2011Interpolating Langlands Quantum Groups of Rank 1 -- We study a certain family, parameterized by an positive integer g, of double deformations of the envelopping algebra U(sl2), in the spirit of arXiv:0809.4453. We prove that each of these double deformations ... More
Dynamical mechanism for ultra-light scalar Dark MatterFeb 11 2015Nov 30 2015Assuming a double-well bare potential for a self-interacting scalar field, with the Higgs vacuum expectation value, it is shown that non-perturbative quantum corrections naturally lead to ultra-light particles of mass $\simeq10^{-23}$eV, if these non-perturbative ... More
A correlation between the amount of dark matter in elliptical galaxies and their shapeJul 28 2014We discuss the correlation between the dark matter content of elliptical galaxies and their ellipticities. We then explore a mechanism for which the correlation would emerge naturally. Such mechanism leads to identifying the dark matter particles to gravitons. ... More
The Physicist's Companion to Current Fluctuations: One-Dimensional Bulk-Driven Lattice GasesJul 15 2015Jul 19 2015One of the main features of statistical systems out of equilibrium is the currents they exhibit in their stationary state: microscopic currents of probability between configurations, which translate into macroscopic currents of mass, charge, etc. Understanding ... More
Generalized Inversions and the Construction of Musical Group and Groupoid ActionsFeb 06 2014Transformational music theory is a recent field in music theory which studies the possible transformations between musical objects, such as chords. In the framework of the theory initiated by David Lewin, the set of all transformations forms a group which ... More
Non-Hermitian Lagrangian for quasi-relativistic fermionsMay 13 2014Dec 09 2014We present a Lorentz-symmetry violating Lagrangian for free fermions, which is local but not Hermitian, whereas the corresponding Hamiltonian is Hermitian but not local. A specific feature of the model is that the dispersion relation is relativistic in ... More
On inverse scattering at high energies for the multidimensional relativistic Newton equation in a long range electromagnetic fieldDec 31 2013We define scattering data for the relativistic Newton equation in an electric field $-\nabla V\in C^1(\R^n,\R^n)$, $n\ge 2$, and in a magnetic field $B\in C^1(\R^n,A_n(\R))$ that decay at infinity like $r^{-\alpha-1}$ for some $\alpha\in (0,1]$, where ... More
The Lawrence-Krammer representation is a quantization of the symmetric square of the Burau representationSep 21 2016We show that the Lawrence--Krammer representation can be obtained as the quantization of the symmetric square of the Burau representation. This construction allows us to find new representations of the braid groups.
Complexity of inheritance of $\mathcal{F}$-convexity for restricted games induced by minimum partitionsAug 25 2016Let $G = (N,E,w)$ be a weighted communication graph (with weight function $w$ on $E$). For every subset $A \subseteq N$, we delete in the subset $E(A)$ of edges with ends in $A$, all edges of minimum weight in $E(A)$. Then the connected components of ... More
On the acylindrical hyperbolicity of the tame automorphism group of $\mathrm{SL}_2(\mathbb{C})$Dec 23 2015Jun 30 2016We introduce the notion of \"uber-contracting element, a strengthening of the notion of strongly contracting element which yields a particularly tractable criterion to show the acylindrical hyperbolicity, and thus a strong form of non-simplicity, of groups ... More
Debugging Frame Semantic Role LabelingJan 22 2019We propose a quantitative and qualitative analysis of the performances of statistical models for frame semantic structure extraction. We report on a replication study on FrameNet 1.7 data and show that preprocessing toolkits play a major role in argument ... More
Revealing the work cost of generalized thermal bathsSep 14 2018We derive the work cost of using generalized thermal baths from the physical equivalence of quantum mechanics under unitary transformations. We demonstrate our method by considering a qubit extracting work from a single bath to amplify a cavity field. ... More
On the Limiting Absorption Principle at zero energy for a new class of possibly non self-adjoint Schr{ö}dinger operatorsAug 23 2018Dec 20 2018We recall a Moure theory adapted to non self-adjoint operators and we apply this theory to Schr{\"o}dinger operators with non real potentials, using different type of conjugate operators. We show that some conjugate operators permits to relax conditions ... More
Structure of $J$-holomorphic disks with immersed Lagrangian boundary conditionsAug 06 2018We explain how to generalize Lazzarini's structural Theorem from [Laz11] to the case of curves with boundary on a given Lagrangian immersion. As a consequence of this result, we show that we can compute Floer homology with time-independent almost complex ... More
Ideas from Developmental Robotics and Embodied AI on the Questions of Ethics in RobotsMar 20 2018Advances in Artificial Intelligence and robotics are currently questioning theethical framework of their applications to deal with potential drifts, as well as the way inwhich these algorithms learn because they will have a strong impact on the behavior ... More
Inheritance of Convexity for the $\mathcal{P}_{\min}$-Restricted GameAug 08 2017May 17 2018We consider restricted games on weighted graphs associated with minimum partitions. We replace in the classical definition of Myerson restricted game the connected components of any subgraph by the subcomponents corresponding to a minimum partition. This ... More
On links between horocyclic and geodesic orbits on geometrically infinite surfacesJul 25 2017We study the topological dynamics of the horocycle flow $h_\mathbb{R}$ on a geometrically infinite hyperbolic surface S. Let u be a non-periodic vector for $h_\mathbb{R}$ in T^1 S. Suppose that the half-geodesic $u(\mathbb{R}^+)$ is almost minimizing ... More
Stacking machine learning classifiers to identify Higgs bosons at the LHCDec 21 2016May 30 2017Machine learning (ML) algorithms have been employed in the problem of classifying signal and background events with high accuracy in particle physics. In this paper, we compare the performance of a widespread ML technique, namely, \emph{stacked generalization}, ... More
The endomorphism ring of projectives and the Bernstein centreMar 05 2018Dec 13 2018Let $F$ be a finite extension of $\mathbb {Q}_{p}$ and $\mathcal{O}_F$ its ring of integers. Let $\Omega$ be a Bernstein component and let $(J, \lambda)$ be an $\Omega$-type. In this paper we will prove that the centre of the Bernstein component $\Omega$ ... More
Trace semantics via determinization for probabilistic transition systemsFeb 25 2018A coalgebraic definition of finite and infinite trace semantics for probabilistic transition systems has recently been given using a certain Kleisli category. In this paper this semantics is developed using a coalgebraic method which is an instance of ... More
Thermal theory of aluminum particle ignition in continuum, free-molecular, and transition heat transfer regimesApr 03 2018Aug 01 2018Most studies on nano- and micro- sized aluminum particle ignition have been focused on the processes occuring inside particles. In the current paper, thermal ignition of an aluminum particle in the air is simulated with different heat transfer models: ... More
Bohr-Sommerfeld Lagrangian submanifolds as minima of convex functionsMar 19 2018We prove that every closed Bohr-Sommerfeld Lagrangian submanifold $Q$ of a symplectic/K\"ahler manifold $X$ can be realised as a Morse-Bott minimum for some 'convex' exhausting function defined in the complement of a symplectic/complex hyperplane section ... More
Implicative algebras: a new foundation for realizability and forcingFeb 02 2018Mar 15 2018We introduce the notion of implicative algebra, a simple algebraic structure intended to factorize the model constructions underlying forcing and realizability (both in intuitionistic and classical logic). The salient feature of this structure is that ... More
A simple and effective parametrisation for Earth-impacting orbitsDec 22 2017This work presents a new parametrisation suitable for parameter-space studies of heliocentric Earth-impacting orbits. Originally motivated by the issue of potentially hazardous asteroids (PHAs) and the mitigation of such a risk, we show that the simultaneous ... More
The index of G-transversally elliptic families in KK-theoryMar 29 2018We define and study the index map for families of G-transversally elliptic operators and introduce the multiplicity for a given irreducible representation as a virtual bundle over the base of the fibration. We then prove the usual axiomatic properties ... More
Brody curves omitting hyperplanesDec 14 2008Jan 21 2009A Brody curve, a.k.a. normal curve, is a holomorphic map from the complex line to the complex projective space of dimension n, such that the family of its translations is normal. We prove that Brody curves omitting n hyperplanes in general position have ... More
Normal holomorphic curves from parabolic regions to projective spacesOct 05 2007A holomorphic map from the complex line to a complex projective space is called normal (a. k. a. Brody curve) if it is uniformly continuous from the Euclidean metric to the Fubini--Study metric. The paper contains a survey of known results about such ... More
Pluripolar sets, real submanifolds and pseudoholomorphic discsJul 25 2018We study boundary properties of plurisubharmonic functions near real submanifolds of almost complex manifolds.
Discs and boundary uniqueness for psh functions on almost complex manifoldsJul 07 2018We prove that a totally real manifold (of maximal dimension) is a boundary uniqueness set for a psh function on an almost complex manifold.
Regularized maximum of strictly plurisubharmonic functions on an almost complex manifoldMar 21 2013Mar 28 2013We prove that the maximum of two smooth strictly plurisubharmonic functions on an almost complex manifold can be uniformly approximated by smooth strictly plurisubharmonic functions.
Convexity at finite temperature and non-extensive thermodynamicsMar 04 2016Aug 02 2016Assuming that tunnel effect between two degenerate bare minima occurs, in a scalar field theory at finite volume, this article studies the consequences for the effective potential, to all loop orders. Convexity is achieved only if the two bare minima ... More
Euler-Poincaré obstruction for pretzels with long tentacles à la Cantor-NyikosDec 22 2011We present an avatar of the Euler obstruction to foliated structures on certain non-metric surfaces. This adumbrates (at least for the simplest 2D-configurations) that the standard mechanism---to the effect that the devil of algebra sometimes barricades ... More
Ebullition in foliated surfaces versus gravitational clumpingNov 24 2011For surfaces, we brush a reasonably sharp picture of the influence of the fundamental group upon the complexity of foliated-dynamics. A metaphor emerges with phase-changes through the solid-liquid-gaseous states. Groups of ranks $0\le r\le 1$ are frozen ... More
Herbert Stahl's proof of the BMV conjectureDec 20 2013The paper contains a simplified version of Stahl's proof of a conjecture of Bessis, Moussa and Villani on the trace of matrices A+tB with Hermitean A and B.
The index of G-transversally elliptic families in cohomologySep 13 2018We define the Chern character of the index class of a $G$-invariant family of $G$-transversally elliptic operators, see [6]. Next we study the Berline-Vergne formula for families in the elliptic and transversally elliptic case.
Co-axial monodromyJun 14 2017For Riemannian metrics of constant positive curvature on a punctured sphere with conic singularities at the punctures and co-axial monodromy of the developing map, possible angles at the singularities are completely described. This completes the recent ... More
On inverse problems for the multidimensional relativistic Newton equation at fixed energyJul 03 2006In this paper, we consider inverse scattering and inverse boundary value problems at sufficiently large and fixed energy for the multidimensional relativistic Newton equation with an external potential $V$, $V\in C^2$. Using known results, we obtain, ... More
Wellposedness and regularity for a degenerate parabolic equation arising in a model of chemotaxis with nonlinear sensitivityDec 12 2012Feb 03 2014We study a one-dimensional parabolic PDE with degenerate diffusion and non-Lipschitz nonlinearity involving the derivative. This evolution equation arises when searching radially symmetric solutions of a chemotaxis model of Patlak-Keller-Segel type. We ... More
A probabilistic algorithm to test local algebraic observability in polynomial timeOct 04 2000The following questions are often encountered in system and control theory. Given an algebraic model of a physical process, which variables can be, in theory, deduced from the input-output behavior of an experiment? How many of the remaining variables ... More
Invariant Gaussian fields on homogeneous spaces: explicit constructions and mean nodal volumeFeb 08 2016Jan 30 2019We study the properties of smooth Gaussian random fields defined on a homogeneous space, under the assumption that the probability distribution is invariant under the isometry group of the space. We first indicate, building on early results on Yaglom, ... More
The Ismagilov conjecture over a finite field ${\mathbb F}_p$Dec 04 2016Jan 31 2017We construct the so-called quasiregular representations of the group $B_0^{\mathbb N}({\mathbb F}_p)$ of infinite upper triangular matrices with coefficients in a finite field and give the criteria of theirs irreducibility in terms of the initial measure. ... More
Cartan-Weyl Basis for Yangian Double $DY(sl_3)$Apr 13 1997We give a new realization of $Y(sl_3)$ via Cartan-Weyl elements. An algebraic description of Yangian Double $DY(sl_3)$, explicit comultiplication formulas and universal R-matrix are obtained in these terms.
Dynamical mass generation in Lorentz-violating QEDSep 29 2010Mar 08 2013A Lorentz violating modification of massless QED is proposed, with higher order space derivatives for the photon field. The fermion dynamical mass generation is studied with the Schwinger-Dyson approach, and it is found that the resulting mass is many ... More
A new non-perturbative time-dependent string configurationAug 10 2007A time-dependent bosonic string configuration is discussed, in graviton and dilaton backgrounds, leading to Weyl-symmetry beta-functions which are homogeneous in X^0, to any order in alpha'. As a consequence, a string reparametrization can always be implemented, ... More
QED in external fields, a functional point of viewJan 17 2001Jun 25 2001A functional partial differential equation is set for the proper graphs generating functional of QED in external electromagnetic fields. This equation leads to the evolution of the proper graphs with the external field amplitude and the external field ... More
Meromorphic functions with three singular valuesSep 01 2003Feb 27 2004The minimal possible rate of growth of a meromorphic function with three critical values is found.
Complexes of Groups and BoundariesJan 30 2012Given a complex of groups over a finite simplicial complex in the sense of Haefliger, we give conditions under which it is possible to build an EZ-structure in the sense of Farrell-Lafont for its fundamental group out of such structures for its local ... More
A Toda lattice in dimension 2 and Nevanlinna theoryNov 07 2004It is shown how to study the 2-D Toda system for SU(n+1) using Nevanlinna theory of meromorphic functions and holomorphic curves. The results generalize recent results of Jost - Wang and Chen - Li.
Criteria of irreducibility of the Koopman representations for the group ${\rm GL}_0(2\infty,{\mathbb R})$Oct 15 2016Our aim is to find the irreducibility criteria for the Koopman representation, when the group acts on some space with a measure (Conjecture 1.5). Some general necessary conditions of the irreducibilty of this representation are established. In the particular ... More
Averaging for some simple constrained Markov processesJun 24 2016Aug 30 2016In this paper, a class of piecewise deterministic Markov processes with underlying fast dynamic is studied. Using a "penalty method" , an averaging result is obtained when the underlying dynamic is infinitely accelerated. The features of the averaged ... More
A Mackey-Analogy based Proof of the Connes-Kasparov Isomorphism for Real Reductive GroupsFeb 29 2016We give a new representation-theory based proof of the Connes-Kasparov conjecture for the K-theory of reduced C*-algebras of real reductive Lie groups. Our main tool is a natural correspondence between the tempered representation theory of such a group ... More
Invariant Gaussian Fields on Homogeneous Spaces : Explicit Constructions and Geometric Measure of the Zero-setFeb 08 2016This paper is concerned with the properties of Gaussian random fields defined on a riemannian homogeneous space, under the assumption that the probability distribution be invariant under the isometry group of the space. We first indicate, building on ... More
Swiss Cheese type operads and models for relative loop spacesNov 18 2015Aug 05 2016We construct a (coloured) operad RL in the category of sets that may be thought of as a combinatorial model for the Swiss Cheese operad. By adapting Batanin-Berger's condensation process we obtain a topological (resp. chain) operad weakly equivalent to ... More
How tempered representations of a semisimple Lie group contract to its Cartan motion groupOct 09 2015George W. Mackey suggested in 1975 that there should be analogies between the irreducible unitary representations of a noncompact semisimple Lie group $G$ and those of its Cartan motion group - the semidirect product $G_0$ of a maximal compact subgroup ... More
Modeling Dense Urban Wireless Networks with 3D Stochastic GeometrySep 10 2015Feb 05 2016Over the past decade, many works on the modeling of wireless networks using stochastic geometry have been proposed. Results about probability of coverage, throughput or mean interference, have been provided for a wide variety of networks (cellular, ad-hoc, ... More
Study of Charmonium Production in Asymmetric Nuclear Collisions by the PHENIX Experiment at RHICSep 11 2015The measurement of quarkonia production in relativistic heavy ion collisions provides a powerful tool for studying the properties of the hot and dense matter created in these collisions. To be really useful, however, such measurements must cover a wide ... More
On the cubical geometry of Higman's groupJun 09 2015Jun 27 2016We investigate the cocompact action of Higman's group on a CAT(0) square complex associated to its standard presentation. We show that this action is in a sense intrinsic, which allows for the use of geometric techniques to study the endomorphisms of ... More
Lorentz-symmetry violation and dynamical flavour oscillationsDec 15 2013We show how a mass mixing matrix can be generated dynamically, for two massless fermion flavours coupled to a Lorentz invariance violating (LIV) gauge field. The LIV features play the role of a regulator for the gap equations, and the non-analytic dependence ... More
Population viewpoint on Hawkes processesApr 24 2015This paper focuses on a class of linear Hawkes processes with general immigrants. These are counting processes with shot noise intensity, including self-excited and externally excited patterns. For such processes, we introduce the concept of age pyramid ... More
The Ismagilov conjecture over a finite field ${\mathbb F}_p$Dec 04 2016We construct the so-called quasiregular representations of the group of infinite upper triangular matrices with coefficients in a finite field and give the criteria of theirs irreducibility in terms of the initial measure. These representations are particular ... More
Generic smooth representationsMar 06 2018Let $F$ be a finite extension of $\mathbb{Q}_p$. Here we give a necessary and sufficient condition for an irreducible smooth representation of $GL_n(F)$ to be generic.
Quasi-cyclic self-dual codes of length 70Apr 05 2017In this paper we obtain a number of [70,35,12] singly even self-dual codes as a quasi-cyclic codes with m=2 (tailbitting convolutional codes). One of them is the first known code with parameters Beta=140 Gamma=0. All codes are not pure double circulant ... More
A non-commutative algorithm for multiplying 5x5 matrices using 99 multiplicationsJul 18 2017Dec 20 2017We present a non-commutative algorithm for multiplying 5x5 matrices using 99 multiplications. This algorithm is a minor modification of Makarov's algorithm which exhibit the previous best known bound with 100 multiplications.
Rich subcontextsJan 12 2017For a finite binary relation, we show a local operation which does not decrease its number of (Galois-)closed sets and eventually increases its (Vapnik-Chervonenkis)-dimension. Specifically, we show that there always exist a pair of elements, one belonging ... More
Invariants of maximal tori and unipotent constituents of some quasi-projective characters for finite classical groupsMay 19 2017We study the decomposition of certain reducible characters of classical groups as the sum of irreducible ones. Let ${\mathbf G}$ be an algebraic group of classical type with defining characteristic $p>0$, $\mu$ a dominant weight and $W$ the Weyl group ... More
Reducing the complexity for class group computations using small defining polynomialsOct 29 2018In this paper, we describe an algorithm that efficiently collect relations in class groups of number fields defined by a small defining polynomial. This conditional improvement consists in testing directly the smoothness of principal ideals generated ... More
On the complexity of class group computations for large degree number fieldsOct 26 2018In this paper, we examine the general algorithm for class group computations, when we do not have a small defining polynomial for the number field. Based on a result of Biasse and Fieker, we simplify their algorithm, improve the complexity analysis and ... More
Nucleon spin structure measurements at Jefferson LabOct 18 2018We summarize the measurements investigating the nucleon spin structure done at Jefferson Lab, a multi-GeV continuous electron beam facility located in Newport News, Virgina, USA. After motivating spin structure studies, we explain how Jefferson Lab uniquely ... More
European Court of Human Right Open Data projectOct 07 2018Feb 04 2019This paper presents thirteen datasets for binary, multiclass and multilabel classification based on the European Court of Human Rights judgments since its creation. The interest of such datasets is explained through the prism of the researcher, the data ... More
Entire functions, PT-symmetry and Voros's quantization schemeOct 08 2015In this paper, A. Avila's theorem on convergence of the exact quantization scheme of A. Voros is related to the reality proofs of eigenvalues of certain PT-symmetric boundary value problems. As a result, a special case of a conjecture of C. Bender, S. ... More
Special Symplectic Subgroup over Integers Arising as a Factor of The Braid GroupFeb 13 2004Oct 20 2004There is a natural action of the braid group on the symmetric matrices with units on the diagonal, appearing in various fields as Singularity Theory, Frobenius Manifolds or Isomonodromic deformations of certain classes of linear differential systems. ... More
Asymptotic matricial models and QWEP property for q-Araki-Woods von Neumann algebrasMay 31 2006Using Speicher central limit Theorem we provide Hiai's q-Araki-Woods von Neumann algebras with nice asymptotic matricial models. Then, we use this model and an elaborated ultraproduct procedure, to show that all q-Araki-Woods von Neumann algebras are ... More
Ahlfors circle maps and total reality: from Riemann to RohlinNov 15 2012Apr 16 2013This is a prejudiced survey on the Ahlfors (extremal) function and the weaker {\it circle maps} (Garabedian-Schiffer's translation of "Kreisabbildung"), i.e. those (branched) maps effecting the conformal representation upon the disc of a {\it compact ... More
Mean Curvature Motion of Graphs with Constant Contact Angle at a Free BoundaryDec 08 2008We consider the motion by mean curvature of an $n$-dimensional graph over a time-dependent domain in $\mathbb{R}^n$, intersecting $\mathbb{R}^n$ at a constant angle. In the general case, we prove local existence for the corresponding quasilinear parabolic ... More
On the analogy between real reductive groups and Cartan motion groups. I: The Mackey-Higson bijectionOct 09 2015Aug 28 2018George Mackey suggested in 1975 that there should be analogies between the irreducible unitary representations of a noncompact reductive Lie group $G$ and those of its Cartan motion group $G_0$ $-$ the semidirect product of a maximal compact subgroup ... More
Geometric Median ShapesOct 29 2018Nov 07 2018We present an algorithm to compute the geometric median of shapes which is based on the extension of median to high dimensions. The median finding problem is formulated as an optimization over distances and it is solved directly using the watershed method ... More
Dynamic Code Coverage with Progressive Detail LevelsJun 19 2013Nowadays, locating software components responsible for observed failures is one of the most expensive and error-prone tasks in the software development process. To improve the debugging process efficiency, some effort was already made to automatically ... More
Simultaneous stabilization, avoidance and Goldberg's constantsAug 03 2012Aug 09 2012This is an exposition for mathematicians of some unsolved problems arising in control theory of linear time-independent systems.
Segre varieties, CR geometry and Lie symmetries of second order PDE systemsFeb 21 2000We show that biholomorphic automorphisms of a real analytic CR manifold can be considered as (pointwise) Lie symmetries of a holomorphic second order PDE system defining its Segre family. This allows to use general methods of the geometric PDE theory ... More
A separable manifold failing to have the homotopy type of a CW-complexSep 23 2006We show that the Pr\"ufer surface, which is a separable non-metrizable 2-manifold, has not the homotopy type of a CW-complex. This will follow easily from J. H. C. Whitehead's result: if one has a good approximation of an arbitrary space by a CW-complex, ... More
Mathematics discovered, invented, and inheritedSep 12 2013Sep 22 2013The classical platonist/formalist dilemma in philosophy of mathematics can be expressed in lay terms as a deceptively naive question: is new mathematics discovered or invented? Using an example from my own mathematical life, I argue that there is also ... More
Acylindrical actions on CAT(0) square complexesSep 10 2015For group actions on hyperbolic CAT(0) square complexes, we show that the acylindricity of the action is equivalent to a weaker form of acylindricity phrased purely in terms of stabilisers of points, which has the advantage of being much more tractable ... More