Results for "Mario Morvan"

total 4310took 0.10s
Pushing the Limits of Exoplanet Discovery via Direct Imaging with Deep LearningApr 12 2019Further advances in exoplanet detection and characterisation require sampling a diverse population of extrasolar planets. One technique to detect these distant worlds is through the direct detection of their thermal emission. The so-called direct imaging ... More
Query Routing and Processing in Peer-To-Peer Data Sharing SystemsMay 29 2010Sharing musical files via the Internet was the essential motivation of early P2P systems. Despite of the great success of the P2P file sharing systems, these systems support only "simple" queries. The focus in such systems is how to carry out an efficient ... More
A non-commutative generalisation of Thurston's gluing equationsMay 22 2016In his famous Princeton Notes, Thurston introduced the so-called gluing equations defining the deformation variety. Later, Kashaev defined a non-commutative ring from H-triangulations of 3-manifolds and observed that for trefoil and figure-eight knot ... More
Multi-level agent-based modeling - A literature surveyMay 02 2012Nov 15 2013During last decade, multi-level agent-based modeling has received significant and dramatically increasing interest. In this article we present a comprehensive and structured review of literature on the subject. We present the main theoretical contributions ... More
Power Systems of the FutureApr 30 2003Electric power is a vital ingredient of modern society. This paper in conjunction with previous papers was written to provide an insight into the physics and engineering that go into electric power systems and their modernization. Topics covered here ... More
Consequences of Gravitational Tunneling RadiationFeb 22 2003Jan 25 2006Gravitational tunneling radiation (GTR) from a black hole is similar to electric field emission of electrons from a metal. There is always a second body to give the gravitational barrier of a black hole a finite rather than infinite width so that a particle ... More
Little Black Holes:Dark Matter And Ball LightningDec 11 2002Small,quiescent black holes can be considered as candidates for the missing dark matter of the universe,and as the core energy source of ball lightning.By means of gravitational tunneling,directed radiation is emitted from black holes in a process much ... More
Gravitational Tunneling RadiationDec 11 2002The isolated black hole radiation of both Hawking and Zel'dovich are idealized abstractions as there is always another body to distort the potential. This is considered with respect to both gravitational tunneling, and black hole "no-hair" theorems. The ... More
Quantum and Classical Disparity and AccordApr 21 2008Sep 23 2008Discrepancies and accords between quantum (QM) and classical mechanics (CM) related to expectation values and periods are found for both the simple harmonic oscillator (SHO) and a free particle in a box (FPB), which may apply generally. These indicate ... More
In Memory of Julian SchwingerMar 20 2003Although he was the recipient of a Nobel Prize and despite the greatness of his accomplishments, Julian Schwinger is almost an unsung hero of our age . He is relatively unknown to the general population, even though in the physics community he was a renowned ... More
On the acceleration of Ultra High Energy Cosmic Rays in Gamma Ray BurstsJun 13 1995UHECRs are roughly isotropic and attain very large energies, $E \gtrsim 3\times 10^{20} \; eV$. Conventional models fail to explain both facts. I show here that acceleration of UHECRs in GRBs satisfies both observational constraints. Using M\'esz\'aros ... More
Dual Gauged SupergravitiesJan 23 2007Apr 02 2007We shall review a novel formulation of four dimensional gauged supergravity which is manifestly covariant with respect to the non-perturbative electric-magnetic duality symmetry transformations of the ungauged theory, at the level of the equations of ... More
On Semiclassical Equivalence of Green-Schwarz and Pure Spinor Strings in AdS(5) x S(5)Feb 11 2013May 14 2013We present a method to study the equivalence at the semiclassical level of the Green-Schwarz and pure spinor formulations of String Theory in AdS(5) x S(5). This method provides a clear separation of the physical and unphysical sectors of the pure spinor ... More
Sur la persistance des courbes invariantes pour les dynamiques holomorphes fibrées lissesSep 12 2007En s'appuyant sur un th\'eor\`me de fonctions implicites de Hamilton nous montrons la persistance d'une courbe invariante indiff\'rente pour une dynamique holomorpphe fibr\'ee en classe $C^{\infty}$. Une condition diophantienne sur la paire de nombres ... More
Moduli of space sheaves with Hilbert polynomial 4m+1Jan 09 2016We investigate the moduli space of sheaves supported on space curves of degree 4 and having Euler characteristic 1. We give an elementary proof of the fact that this moduli space consists of three irreducible components. We study the local geometry at ... More
Reduction Semantics in Markovian Process AlgebraDec 22 2015Stochastic (Markovian) process algebra extend classical process algebra with probabilistic exponentially distributed time durations denoted by rates (the parameter of the exponential distribution). Defining a semantics for such an algebra, so to derive ... More
Financial market models in discrete time beyond the concave caseDec 06 2015In this article we propose a study of market models starting from a set of axioms, as one does in the case of risk measures. We define a market model simply as a mapping from the set of adapted strategies to the set of random variables describing the ... More
Eigenvalues of symmetric matrices over integral domainsNov 03 2015Mar 09 2016Given an integral domain A we consider the set of all integral elements over A that can occur as an eigenvalue of a symmetric matrix over A. We give a sufficient criterion for being such an element. In the case where A is the ring of integers of an algebraic ... More
Commercially available Geiger mode single-photon avalanche photodiode with a very low afterpulsing probabilityMay 17 2015Afterpulsing is one of the main technological flaws present in photon counting detectors based on solid-state semiconductor avalanche photodiodes operated in Geiger mode. Level of afterpulsing depends mainly on type of the semiconductor, doping concentrations ... More
New wavelet-based superresolution algorithm for speckle reduction in SAR imagesJul 31 2016This paper describes a novel projection algorithm, the Projection Onto Span Algorithm (POSA) for wavelet-based superresolution and removing speckle (in wavelet domain) of unknown variance from Synthetic Aperture Radar (SAR) images. Although the POSA is ... More
Union is strength in lossy image compressionJul 31 2016In this work, we present a comparison between different techniques of image compression. First, the image is divided in blocks which are organized according to a certain scan. Later, several compression techniques are applied, combined or alone. Such ... More
New version of Gram-Schmidt Process with inverse for Signal and Image ProcessingJul 16 2016The Gram-Schmidt Process (GSP) is used to convert a non-orthogonal basis (a set of linearly independent vectors, matrices, etc) into an orthonormal basis (a set of orthogonal, unit-length vectors, bi or tri dimensional matrices). The process consists ... More
Quantum Boolean Image DenoisingAug 11 2014A quantum Boolean image processing methodology is presented in this work, with special emphasis in image denoising. A new approach for internal image representation is outlined together with two new interfaces: classical-to-quantum and quantum-to-classical. ... More
Interface-driven magnetocapacitance in a broad range of materialsApr 15 2008Triggered by the revival of multiferroic materials, a lot of effort is presently undergoing as to find a coupling between a capacitance and a magnetic field. We show in this report that interfaces are the right way of increasing such a coupling provided ... More
Construction of PMDS and SD Codes extending RAID 5Apr 30 2013A construction of Partial Maximum Distance Separable (PMDS) and Sector-Disk (SD) codes extending RAID 5 with two extra parities is given, solving an open problem. Previous constructions relied on computer searches, while our constructions provide a theoretical ... More
Process POVM: A mathematical framework for the description of process tomography experimentsFeb 26 2008Jul 09 2008In this paper we shall introduce the mathematical framework for the description of measurements of quantum processes. Using this framework the process estimation problems can be treated in the similar way as the state estimation problems, only replacing ... More
Incomplete quantum process tomography and principle of maximal entropyFeb 26 2008Jan 07 2009The main goal of this paper is to extend and apply the principle of maximum entropy (MaxEnt) to incomplete quantum process estimation tasks. We will define a so-called process entropy function being the von Neumann entropy of the state associated with ... More
Observed and Physical Properties of Core-Collapse SupernovaeSep 10 2002I use photometry and spectroscopy data for 24 Type II plateau supernovae to examine their observed and physical properties. This dataset shows that these objects encompass a wide range of ~5 mag in their plateau luminosities, their expansion velocities ... More
Physical Consonance Law of Sound WavesDec 20 2004Jun 16 2005Sound consonance is the reason why it is possible to exist music in our life. However, rules of consonance between sounds had been found quite subjectively, just by hearing. To care for, the proposal is to establish a sound consonance law on the basis ... More
Uniformization of Sierpiński carpets in the planeSep 21 2010Mar 07 2011Let $S_i$, $i\in I$, be a countable collection of Jordan curves in the extended complex plane $\Sph$ that bound pairwise disjoint closed Jordan regions. If the Jordan curves are uniform quasicircles and are uniformly relatively separated, then there exists ... More
Optimal driving protocols for nano-sized devices and their dependence on couplings to reservoirsSep 25 2013Mar 16 2014The development of efficient artificial nanodevices poses challenges which are of fundamental and technological nature. Recent progress has been made in the context of finite-time thermodynamics. A central question in finite-time thermodynamics is to ... More
The world according to the Hubble Space TelescopeMar 21 2003The Hubble Space Telescope (HST), in its thirteen years of operation, has allowed us to observe properties of the universe humans have been able, until very recently, to probe only with their thoughts. This review presents a brief summary of a few of ... More
Basis functions for strongly correlated Fermi systemsApr 05 1995A general method to construct basis functions for fermionic systems which account for the $SU(2)$ symmetry and for the translational invariance of the Hamiltonian is presented. The method does not depend on the dimensionality of the system and it appears ... More
Macroscopic quantum bound states of Bose Einstein condensates in optical latticesNov 27 2003We discuss localized ground states of the periodic Gross-Pitaevskii equation in the framework of a quantum linear Schr\"odinger equation with effective potential determined in self-consistent manner. We show that depending on the interaction among the ... More
Starless CoresApr 23 2005Dense low mass cores in nearby clouds like Taurus and Auriga are some of the simplest sites currently forming stars like our Sun. Because of their simplicity and proximity, dense cores offer the clearest view of the different phases of star formation, ... More
Time evolutions in Quantum mechanics and (Lorentzian) geometryJan 29 2003As R.Feynman has shown to F. Dyson -- who published it then in 1990 under the name of "Feynman's proof of Maxwell's equations" -- the only interactions compatible with the canonical uncertainty relation (for scalar particles on flat $\R^3$) are the Lorentz ... More
Decoherence in non integrable systemsMar 23 2005Self-induced decoherence formalism and the corresponding classical limit are extended from quantum integrable systems to non-integrable ones.
The Mathematical Structure of Superspace as a Consequence of Time AsymmetryApr 17 1996It is demonstrated how a convenient choice of the mathematical structure of the quantum cosmology superspace, precisely the definition of a convenient regular state superspace and the restriction of the dynamics to this space, yields directly to an irreversible ... More
A Monte Carlo method for integration of multivariate smooth functions I: Sobolev spacesApr 20 2016We study a Monte Carlo algorithm that is based on a specific (randomly shifted and dilated) lattice point set. The main result of this paper is that the mean squared error for a given compactly supported, square-integrable function is bounded by $n^{-1/2}$ ... More
A description of the assembly map for the Baum-Connes conjecture with coefficientsNov 11 2016In this note we set a configuration space description of the equivariant connective K-homology groups with coefficients in a unital C*-algebra for proper actions. Over this model we define a connective assembly map and prove that in this setting is possible ... More
The dynamic electron-correlation energy in the NOF-MP2 method from the orbital-invariant perturbation theoryAug 18 2018Aug 21 2018The original formulation (Phys. Rev. Lett. 119, 063002, 2017) of the natural orbital functional - second-order M{\o}ller-Plesset (NOF-MP2) method is based on the MP2 that uses the canonical Hartree-Fock molecular orbitals. The current work presents a ... More
Measurement of the evolution of technology: A new perspectiveMar 23 2018A fundamental problem in technological studies is how to measure the evolution of technology. The literature has suggested several approaches to measuring the level of technology (or state-of-the-art) and changes in technology. However, the measurement ... More
Probing primordial features with the primary CMBJul 15 2018CMB photons travel from the last scattering surface, when the primary CMB has been generated, along the surface of the light cone to us. During their travel, they are affected by many secondary effects such as the integrated Sachs-Wolfe effect and CMB ... More
Disruptive firmsOct 17 2017This study proposes the concept of disruptive firms: they are firms with market leadership that deliberate introduce new and improved generations of durable goods that destroy, directly or indirectly, similar products present in markets in order to support ... More
Adaptive Fixed Point Iterations for Semilinear Elliptic Partial Differential EquationsJun 27 2017In this paper we study the behavior of finite dimensional fixed point iterations, induced by discretization of a continuous fixed point iteration defined within a Banach space setting. We show that the difference between the discrete sequence and its ... More
On the connectivity of the hyperbolicity region of irreducible polynomialsApr 14 2017We give an elementary proof for the fact that an irreducible hyperbolic polynomial has only one pair of hyperbolicity cones.
Hyperbolic Sets and Entropy at the Homological LevelJul 18 2014The aim of this work is to study a kind of refinement of the entropy conjecture, in the context of partially hyperbolic diffeomorphisms with one dimensional central direction, of d-dimensional torus. We start by establishing a connection between the unstable ... More
Scalar Curvature on Compact Symmetric SpacesJul 12 2010A classic result by Gromov and Lawson states that a Riemannian metric of non--negative scalar curvature on the Torus must be flat. The analogous rigidity result for the standard sphere was shown by Llarull. Later Goette and Semmelmann generalized it to ... More
A note on self improvement of Poincaré-Sobolev inequalities via Garsia-Rodemich spacesSep 30 2015May 16 2016We use the characterization of weak type inequalities via Garsia-Rodemich conditions to show self improving properties of Poincar\'e-Sobolev inequalities in a very general context.
The Centroid Method for Imaging through TurbulenceJun 15 2012Jun 19 2012A simple and effective method for imaging through ground-level atmospheric turbulence.
Moduli of space sheaves with Hilbert polynomial 4m+1Jan 09 2016May 04 2017We investigate the moduli space of sheaves supported on space curves of degree 4 and having Euler characteristic 1. We give an elementary proof of the fact that this moduli space consists of three irreducible components.
ABP inequalities for singular submanifolds of bounded mean curvatureSep 06 2018Employing a notion of curvature for arbitrary closed sets we prove an ABP-type estimate for a class of singular submanifolds of arbitrary codimension and bounded mean curvature recently introduced by B. White. A weak-Harnack-type estimate is then derived ... More
On two Notions of SemistabilityMar 28 2007Dec 15 2007We show that certain semistable sheaves on the projective plane with linear Hilbert polynomial are cokernels of semistable morphisms of decomposable sheaves.We exhibit certain locally closed subvarieties of moduli spaces of semistable sheaves as quotients ... More
Formalizing computability theory via partial recursive functionsOct 19 2018Apr 01 2019We present an extension to the $\mathtt{mathlib}$ library of the Lean theorem prover formalizing the foundations of computability theory. We use primitive recursive functions and partial recursive functions as the main objects of study, and we use a constructive ... More
Surprising Pfaffian factorizations in Random Matrix Theory with Dyson index $β=2$Sep 23 2011Jul 26 2013In the past decades, determinants and Pfaffians were found for eigenvalue correlations of various random matrix ensembles. These structures simplify the average over a large number of ratios of characteristic polynomials to integrations over one and two ... More
The spherical image of singular varieties of bounded mean curvatureMar 25 2019In this paper we study singular varieties of arbitrary codimension and bounded mean curvature in a viscosity sense. These varieties, introduced by White, naturally arise in the study of the area-blow up of sequences of smooth submanifolds with uniformly ... More
File Managing and Program Execution in Web Operating SystemsMay 27 2010Web Operating Systems can be seen as an extension of traditional Operating Systems where the addresses used to manage files and execute programs (via the basic load/execution mechanism) are extended from local filesystem path-names to URLs. A first consequence ... More
Technological integration and hyper-connectivity: Tools for promoting extreme human lifespansFeb 27 2014Artificial, neurobiological, and social networks are three distinct complex adaptive systems (CAS), each containing discrete processing units (nodes, neurons, and humans respectively). Despite the apparent differences, these three networks are bound by ... More
Notes on optimality of direct characterisation of quantum dynamicsMar 17 2006We argue that the claimed optimality of a new process tomography method suggested in [quant-ph/0601033] and [quant-ph/0601034] is based on not completely fair comparison that does not take into account the available information in an equal way. We also ... More
The acceleration of the Universe in the light of supernovae -- The key role of the Cerro Tololo Inter-American ObservatoryNov 20 2013Dec 09 2013The discovery of acceleration and dark energy arguably constitutes the most revolutionary discovery in astrophysics in recent years. Cerro Tololo Inter-American Observatory (CTIO) played a key role in this amazing discovery through three systematic supernova ... More
Observed and physical properties of type II plateau supernovaeOct 01 2003I use photometry and spectroscopy data for 24 Type II plateau supernovae to examine their observed and physical properties. This dataset shows that these objects encompass a wide range in their observed properties (plateau luminosities, tail luminosities, ... More
Percolation and Cluster Formalism in Continuous Spin SystemsOct 21 1997The generalization of Kasteleyn and Fortuin clusters formalism is introduced in XY (or more generally O(n)) models. Clusters geometrical structure may be linked to spin physical properties as correlation functions. To investigate percolative characteristics, ... More
Mapping Between Nonlinear Schödinger Equations with Real and Complex PotentialsJun 16 2013A mapping between stationary solutions of nonlinear Sch\"odinger equations with real and complex potentials is constructed and a set of exact solutions with real energies are obtained for a large class of complex potentials. As specific examples we consider ... More
SO(4) invariant basis functions for strongly correlated Fermi systemsMar 27 1996Mar 29 1996We show how to construct SO(4) invariant functions for strongly correlated Fermi systems on lattices of finite sizes. We illustrate the method on the case of the 1D Hubbard chain with four and with six sites.
How Rare Are Extraterrestrial Civilizations and When Did They Emerge?Aug 21 1998It is shown that, contrary to an existing claim, the near equality between the lifetime of the sun and the timescale of biological evolution on earth does not necessarily imply that extraterrestrial civilizations are exceedingly rare. Furthermore, on ... More
The experimental future of Neutrino OscillationsOct 03 2000After the recent experimental results on neutrino oscillations, some shape starts to emerge from the puzzle. However, the situation is still far from being clarified. First of all, accommodating all experimental results in a single and simple framework ... More
Review on new Neutrino Oscillation ExperimentsMay 19 1999Driven by new experimental results, in the latest period several new neutrino oscillation experiments have been proposed. I will outline the main ideas behind the different proposals, in particular concerning atmospheric neutrinos and neutrinos from accelerated ... More
The classical-statistical limit of quantum mechanicsMar 23 2005The classical-statistical limit of quantum mechanics is studied. It is proved that the limit $\hbar \to 0$ is the good limit for the operators algebra but it si not so for the state compact set. In the last case decoherence must be invoked to obtain the ... More
An adjusted payoff-based procedure for normal form gamesJun 28 2011We study a simple adaptive model in the framework of an $N$-player normal form game. The model consists of a repeated game where the players only know their own strategy space and their own payoff scored at each stage. The information about the other ... More
Managing Object-Oriented Integration and Regression TestingFeb 05 1999Systematic testing of object-oriented software turned out to be much more complex than testing conventional software. Especially the highly incremental and iterative development cycle demands both many more changes and partially implemented resp. re-implemented ... More
Mass Determination of New Particle StatesMay 09 2009We study theoretical and experimental facets of mass determination of new particle states. Assuming supersymmetry, we update the quark and lepton mass matrices at the grand unification scale accounting for threshold corrections enhanced by large tan beta. ... More
Coronal Gamma Ray Bursts as the sources of Ultra High Energy Cosmic Rays?Oct 30 1995I consider the possibility that Ultra High Energy Cosmic Rays are accelerated in Gamma Ray Bursts located in the Galactic corona, thus circumventing the problem raised by Greisen--Zatsepin--Kuz'min cutoff. The acceleration of UHECRs could occur in the ... More
GeV Photons from Ultra High Energy Cosmic Rays accelerated in Gamma Ray BurstsMay 09 1997Gamma-ray bursts are produced by the dissipation of the kinetic energy of a highly relativistic fireball, via the formation of a collisionless shock. When this happens, Ultra High Energy Cosmic Rays up to 10^20 eV are produced. I show in this paper that ... More
Effective Medium Response of Metallic Nanowire Arrays with a Kerr-type Dielectric HostMar 27 2013Mar 30 2013We derive an effective medium model to characterize the macroscopic electromagnetic response of metallic nanowire arrays embedded in a host dielectric with a Kerr-type nonlinear permittivity function. It is shown that the macroscopic electromagnetic fields ... More
Nonlocal Homogenization Model for a Periodic Array of Epsilon-Negative RodsFeb 20 2006Oct 26 2006We propose an effective permittivity model to homogenize an array of long thin epsilon-negative rods arranged in a periodic lattice. It is proved that the effect of spatial dispersion in this electromagnetic crystal cannot be neglected, and that the medium ... More
Quantum Side Information: Uncertainty Relations, Extractors, Channel SimulationsOct 17 2013In the first part of this thesis, we discuss the algebraic approach to classical and quantum physics and develop information theoretic concepts within this setup. In the second part, we discuss the uncertainty principle in quantum mechanics. The principle ... More
Falling Bodies: the Obvious,the Subtle, and the WrongFeb 19 2007Mar 28 2009An important scientific debate took place regarding falling bodies hundreds of years ago, and it still warrants introspection. Galileo argued that in a vacuum all bodies fall at the same rate relative to the earth, independent of their mass. Aristotle ... More
Vacuum Calorimetry in Exploding Wire StudiesJul 24 2003Jul 25 2003A method of using vacuum calorimetry as a means of determining directly the energy deposited in an electrically exploded wire is presented. This energy determination is compared with that given by the time integral of the product of voltage and current. ... More
Lilienfeld Transition Radiation Brought to LightJul 09 2003Presently, the term transition radiation tends to denote a somewhat different physical phenomenon than the original transition radiation discovered by J. E. Lilienfeld in 1919, and re-employed in different forms again in 1953 and 1971. Lilienfeld transition ... More
Microwave Residual Surface Resistance of SuperconductorsApr 06 2003Two distinct models account for the microwave residual surface resistance of superconducting cavities with equally good agreement with the measured temperature and frequency dependence. In presenting his phonon-generation model, Passow claimed that Rabinowitz' ... More
Black Hole Radiation and Volume Statistical EntropyJun 03 2005Jun 29 2005The simplest possible equation for Hawking radiation, and other black hole radiated power is derived in terms of black hole density. Black hole density also leads to the simplest possible model of a gas of elementary constituents confined inside a gravitational ... More
Rotating Superconductors and the Frame-independent London EquationJun 25 1998A frame-independent, thermodynamically exact London equation is presented, which is especially valid for rotating superconductors. A direct result is the unexpectedly high accuracy ($\sim10^{-10}$) for the usual expression of the London moment.
The Onsager Symmetry Relation and the Time Inversion Invariance of the Entropy ProductionJun 26 1998Starting from the entropy production being invariant under time reversal, one can (i) easily proof, and understand, many aspects of the linear Onsager relations and (ii) deduce the result that all quadratic Onsager coefficients for hydrodynamic fluxes ... More
An example showing that fibred quadratic polynomials admit many attracting curvesSep 11 2009We present an example of a fibred quadratic polynomial admitting an attracting invariant 2-curve. By an unfolding construction we obtain an example of a fibred quadratic polynomial admitting two attracting invariant curves. This phenomena can not occur ... More
Hyperbolization of cocycles by isometries of the euclidean spaceOct 04 2012We study hyperbolized versions of cohomological equations that appear with cocycles by isometries of the euclidean space. These (hyperbolized versions of) equations have a unique continuous solution. We concentrate in to know whether or not these solutions ... More
Polarons, free charge localisation and effective dielectric permittivity in oxidesJun 18 2010This review will deal with several types of free charge localisation in oxides and their consequences on the effective dielectric spectra of such materials. The first one is the polaronic localisation at the unit cell scale on residual impurities in ferroelectric ... More
Pure Spinor Approach to Type IIA Superstring Sigma Models and Free Differential AlgebrasFeb 18 2010Jun 21 2010This paper considers the Free Differential Algebra and rheonomic parametrization of type IIA Supergravity, extended to include the BRS differential and the ghosts. We consider not only the ghosts lambda's of supersymmetry but also the ghosts corresponding ... More
A note on the dispersion of admissible latticesOct 24 2017In this note we show that the volume of axis-parallel boxes in $\mathbb{R}^d$ which do not intersect an admissible lattice $\mathbb{L}\subset\mathbb{R}^d$ is uniformly bounded. In particular, this implies that the dispersion of the dilated lattices $N^{-1/d}\mathbb{L}$ ... More
Exact Sampling for the Ising Model at all TemperaturesDec 17 2010May 11 2011We give a survey of the known results on mixing time of Glauber dynamics for the Ising model on the square lattice and present a technique that makes exact sampling of the Ising model at all temperatures possible in polynomial time. At high temperatures ... More
Adaptive Newton-Type Schemes Based on ProjectionsSep 12 2018Oct 23 2018In this work we present and discuss a possible globalization concept for Newton-type methods. We consider nonlinear problems $f(x)=0$ in $\mathbb{R}^{n}$ using the concepts from ordinary differential equations as a basis for the proposed numerical solution ... More
A Lean formalization of Matiyasevič's TheoremFeb 06 2018In this paper, we present a formalization of Matiyasevi\v{c}'s theorem, which states that the power function is Diophantine, forming the last and hardest piece of the MRDP theorem of the unsolvability of Hilbert's 10th problem. The formalization is performed ... More
A finite difference method for Piecewise Deterministic Processes with memoryOct 24 2006Nov 10 2006In this paper the numerical approximation of solutions of Liouville-Master Equations for time-dependent distribution functions of Piecewise Deterministic Processes with memory is considered. These equations are linear hyperbolic PDEs with non-constant ... More
WdW-patches in AdS$_{3}$ and complexity change under conformal transformations IIFeb 18 2019We study the null-boundaries of Wheeler-de Witt (WdW) patches in three dimensional Poincare-AdS, when the selected boundary timeslice is an arbitrary (non-constant) function, presenting some useful analytic statements about them. Special attention will ... More
Black Hole ParadoxesDec 03 2004Feb 24 2005The Black Hole enigma has produced many paradoxes. A consensus regarding the resolution of some conundrums such as the Naked Singularity Paradox and the Black Hole Lost Information Paradox (LIP) has still not been achieved. Black hole complementarity ... More
On the geometry of the moduli space of sheaves supported on curves of genus four contained in a quadric surfaceApr 24 2017We study the moduli space of stable sheaves of Euler characteristic 1 supported on curves of bidegree (3, 3) contained in a smooth quadric surface. We show that this moduli space is rational. We compute its Betti numbers by studying the variation of the ... More
The classification of semi-stable plane sheaves supported on sextic curvesMay 01 2012Sep 16 2012We classify all Gieseker semi-stable sheaves on the complex projective plane that have dimension 1 and multiplicity 6. We decompose their moduli spaces into strata which occur naturally as quotients modulo actions of certain algebraic groups. In most ... More
On the homology of the moduli space of plane sheaves with Hilbert polynomial 5m+3May 23 2013We compute the Hodge numbers of the moduli space of semi-stable sheaves on the complex projective plane supported on quintic curves and having Euler characteristic 3. For this purpose we study the fixed-point set for a certain torus action on the moduli ... More
Sequences related to convergents to square root of rationalsMay 19 2003Jun 30 2003In this note we study some sequences whose ratio converges to the square root of rationals. Further we analyze some related sequences obtained when the above mentioned ratio simplifies.
On the roots of the cubic defining the Tribonacci sequencesSep 20 2002We consider a sequence of sums of powers of the the roots of the cubic equation characterizing the Tribonacci sequences and derive its relationship with a particular Tribonacci sequence. Then we make a conjecture on the possible generalization.
Identities for Tribonacci-related sequencesSep 15 2002We establish some identities relating two sequences that are, as explained, related to the Tribonacci sequence. One of these sequences bears the same resemblance to the Tribonacci sequence as the Lucas sequence does to the Fibonacci sequence. Defining ... More