Results for "Ulisses Braga-Neto"

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Control of Gene Regulatory Networks with Noisy Measurements and Uncertain InputsFeb 24 2017This paper is concerned with the problem of stochastic control of gene regulatory networks (GRNs) observed indirectly through noisy measurements and with uncertainty in the intervention inputs. The partial observability of the gene states and uncertainty ... More
Particle Filters for Partially-Observed Boolean Dynamical SystemsFeb 23 2017Partially-observed Boolean dynamical systems (POBDS) are a general class of nonlinear models with application in estimation and control of Boolean processes based on noisy and incomplete measurements. The optimal minimum mean square error (MMSE) algorithms ... More
Rank discriminants for predicting phenotypes from RNA expressionJan 07 2014Nov 21 2014Statistical methods for analyzing large-scale biomolecular data are commonplace in computational biology. A notable example is phenotype prediction from gene expression data, for instance, detecting human cancers, differentiating subtypes and predicting ... More
The De Giorgi conjecture on elliptic regularizationOct 18 2010Nov 02 2010We prove a conjecture by De Giorgi on the elliptic regularization of semilinear wave equations in the finite-time case.
A variational principle for hardening elastoplasticityOct 12 2007We present a variational principle governing the quasistatic evolution of a linearized elastoplastic material. In case of linear hardening, the novel characterization allows to recover and partly extend some known results and proves itself to be especially ... More
Learning Maximum Entropy Models from finite size datasets: a fast Data-Driven algorithm allows sampling from the posterior distributionJul 15 2015Sep 08 2016Maximum entropy models provide the least constrained probability distributions that reproduce statistical properties of experimental datasets. In this work we characterize the learning dynamics that maximizes the log-likelihood in the case of large but ... More
Scalable optimal Bayesian classification of single-cell trajectories under regulatory model uncertaintyFeb 08 2019Single-cell gene expression measurements offer opportunities in deriving mechanistic understanding of complex diseases, including cancer. However, due to the complex regulatory machinery of the cell, gene regulatory network (GRN) model inference based ... More
Sequential Experimental Design for Optimal Structural Intervention in Gene Regulatory Networks Based on the Mean Objective Cost of UncertaintyMay 30 2018Scientists are attempting to use models of ever increasing complexity, especially in medicine, where gene-based diseases such as cancer require better modeling of cell regulation. Complex models suffer from uncertainty and experiments are needed to reduce ... More
Finite thermoelastoplasticity and creep under small elastic strainsApr 16 2018A mathematical model for an elastoplastic continuum subject to large strains is presented. The inelastic response is modeled within the frame of rate-dependent gradient plasticity for nonsimple materials. Heat diffuses through the continuum by the Fourier ... More
Graphene ground statesFeb 14 2018Feb 15 2018Graphene is locally two-dimensional but not flat. Nanoscale ripples appear in suspended samples and rolling-up often occurs when boundaries are not fixed. We address this variety of graphene geometries by classifying all ground-state deformations of the ... More
Spectroscopy, Photometry and Micro-arcsec Astrometry of Binaries with the GAIA Space Mission and with the RAVE ExperimentJun 01 2003GAIA astrometric mission of ESA will be very efficient in discovering binary and multiple stars with any orbital period, from minutes to millions of years. Main parameters of the revised mission design are presented. Next we estimate the fraction of binary ... More
Photometry of the progenitor of Nova Del 2013 (V339 Del) and calibration of a deep BVRI photometricDec 20 2013The Asiago plate archive has been searched for old plates covering the region of the sky containing Nova Del 2013 (V339 Del). The brightness of the progenitor was measured against a deep BVRI photometric sequence that we calibrated on purpose. The mean ... More
UBVRI photometric sequences for symbiotic starsAug 16 2002Deep, wide-range and accurate UBVRI photometric sequences have been established around more than 80 symbiotic stars, to assist current photometry as well as measurement of old photographic plates. Sequences for 40 symbiotic stars have already been published; ... More
Kinematics and binaries in young stellar aggregatesDec 11 1998Internal kinematics, spectroscopic binaries and galactic motion are investigated for the trapezium system BD+00.1617 (which lies at the heart of the young open cluster Bochum 2) by means on 73 high resolution Echelle+CCD spectra secured over the period ... More
Linearized plasticity is the evolutionary Γ-limit of finite plasticityNov 04 2011We provide a rigorous justification of the classical linearization approach in plasticity. By taking the small-deformations limit, we prove via \Gamma-convergence for rate-independent processes that energetic solutions of the quasi-static finite-strain ... More
Thermodynamics of elastoplastic porous rocks at large strains towards earthquake modelingJul 02 2018Jul 05 2018A mathematical model for an elastoplastic porous continuum subject to large strains in combination with reversible damage (aging), evolving porosity, water and heat transfer is advanced. The inelastic response is modeled within the frame of plasticity ... More
Finite plasticity in $P^T P$Sep 29 2015We discuss a finite-plasticity model based on the symmetric tensor $P^T P$ instead of the classical plastic strain $P$. Such a model structure arises from assuming that the material behavior is invariant with respect to frame transformations of the intermediate ... More
Coarse and uniform embeddingsDec 09 2015Dec 22 2016In these notes, we study the relation between uniform and coarse embeddings between Banach spaces. In order to understand this relation better, we also look at the problem of when a coarse embedding can be assumed to be topological. Among other results, ... More
On the complexity of some inevitable classes of separable Banach spacesAug 08 2015In this paper, we study the descriptive complexity of some inevitable classes of Banach spaces. Precisely, as shown in [Go], every Banach space either contains a hereditarily indecomposable subspace or an unconditional basis, and, as shown in [FR], every ... More
On asymptotically uniformly smoothness and nonlinear geometry of Banach spacesAug 09 2018These notes concern the nonlinear geometry of Banach spaces, asymptotic uniform smoothness and several Banach-Saks-like properties. We study the existence of certain concentration inequalities in asymptotically uniformly smooth Banach spaces as well as ... More
Configurational Temperature Control for Atomic and Molecular SystemsSep 11 2007A new configurational temperature thermostat suitable for molecules with holonomic constraints is derived. This thermostat has a simple set of motion equations, can generate the canonical ensemble in both position and momentum space, acts homogeneously ... More
Optimal control of a rate-independent evolution equation via viscous regularizationJul 04 2016We study the optimal control of a rate-independent system that is driven by a convex, quadratic energy. Since the associated solution mapping is non-smooth, the analysis of such control problems is challenging. In order to derive optimality conditions, ... More
The geometry of C_60: a rigorous approach via Molecular MechanicsApr 07 2016Jan 09 2017Molecular Mechanics describes molecules as particle configurations interacting via classical potentials. These {\it configurational energies} usually consist of the sum of different phenomenological terms which are tailored to the description of specific ... More
Existence results for incompressible magnetoelasticityNov 16 2013Nov 29 2013We investigate a variational theory for magnetoelastic solids under the incompressibility constraint. The state of the system is described by deformation and magnetization. While the former is classically related to the reference configuration, magnetization ... More
Dynamic perfect plasticity and damage in viscoelastic solidsApr 03 2019In this paper we analyze an isothermal and isotropic model for viscoelastic media combining linearized perfect plasticity (allowing for concentration of plastic strain and development of shear bands) and damage effects in a dynamic setting. The interplay ... More
The maximum time of 2-neighbor bootstrap percolation: complexity resultsAug 27 2015In 2-neighborhood bootstrap percolation on a graph G, an infection spreads according to the following deterministic rule: infected vertices of G remain infected forever and in consecutive rounds healthy vertices with at least 2 already infected neighbors ... More
Constructive Setting of the Density Ratio Estimation Problem and its Rigorous SolutionJun 03 2013Jun 15 2013We introduce a general constructive setting of the density ratio estimation problem as a solution of a (multidimensional) integral equation. In this equation, not only its right hand side is known approximately, but also the integral operator is defined ... More
Coarse embeddings into superstable spacesApr 14 2017Mar 21 2018Krivine and Maurey proved in 1981 that every stable Banach space contains almost isometric copies of $\ell_p$, for some $p\in[1,\infty)$. In 1983, Raynaud showed that if a Banach space uniformly embeds into a superstable Banach space, then $X$ must contain ... More
Thermal width of heavy quarkonia from an AdS/QCD modelJun 30 2016We estimate the thermal width of a heavy quark anti-quark pair inside a strongly coupled plasma using a holographic AdS/QCD model. The imaginary part of the quark potential that produces the thermal width appears in the gravity dual from quantum fluctuations ... More
COUPLING CHIRAL BOSONS TO GRAVITYJan 18 1995The chiral boson actions of Floreanini and Jackiw (FJ), and of McClain,Wu and Yu (MWY) have been recently shown to be different representations of the same chiral boson theory. MWY displays manifest covariance and also a (gauge) symmetry that is hidden ... More
Chiral Bosons as solutions of the BV master equation 2D chiral gauge theoriesFeb 25 1994We construct the chiral Wess-Zumino term as a solution for the Batalin-Vilkovisky master equation for anomalous two-dimensional gauge theories, working in an extended field-antifield space, where the gauge group elements are introduced as additional degrees ... More
Positronium Portal into Hidden Sector: A new Experiment to Search for Mirror Dark MatterMay 26 2010Jul 19 2010The understanding of the origin of dark matter has great importance for cosmology and particle physics. Several interesting extensions of the standard model dealing with solution of this problem motivate the concept of hidden sectors consisting of SU(3)xSU(2)_LxU(1)_Y ... More
INTEGRAL observations of Sco X-1: evidence for Comptonization up to 200 keVJan 29 2013We have analyzed a long-term database for Sco X-1 obtained with the telescope IBIS onboard the INTEGRAL satellite in order to study the hard X-ray behavior of Sco X-1 from 20 up to 200 keV. Besides the data used for producing of the INTEGRAL catalog of ... More
Resilience Analysis for Competing PopulationsMar 14 2019Ecological resilience refers to the ability of a system to retain its state when subject to state variables perturbations or parameter changes. While understanding and quantifying resilience is crucial to anticipate the possible regime shifts, characterizing ... More
Towards the Modular Specification and Validation of Cyber-Physical SystemsMar 08 2018Cyber-Physical Systems (CPS) are systems controlled by one or more computer-based components tightly integrated with a set of physical components, typically described as sensors and actuators, that can either be directly attached to the computer components, ... More
Resilience Analysis for Competing PopulationsMar 14 2019Mar 28 2019Ecological resilience refers to the ability of a system to retain its state when subject to state variables perturbations or parameter changes. While understanding and quantifying resilience is crucial to anticipate the possible regime shifts, characterizing ... More
Accurate orbital solution for the new and metal poor eclipsing binary Tycho~5227-1023-1May 16 2017The orbit and physical parameters of the previously unsolved double-lined eclipsing binary Tyc 5227-1023-1, discovered during the search for RR Lyr variables candidate members of the Aquarius stream, are derived using high resolution \'echelle spectroscopy ... More
Microlocal Versal Deformations of Plane CurvesDec 04 2009We introduce the notion of microlocal versal deformation of a plane curve. We construct equisingular versal deformations of Legendrian curves that are the conormal of a semi-quasi-homogeneous branch.
Fundamental Constants, Entropic Gravity and Nonextensive Equipartition TheoremJan 14 2011Apr 23 2012By using the Verlinde's formalism[1], we propose that the positive numerical factor, in which Klinkhamer[2] states that it is necessary to define the fundamental length, can be associated to the parameter q of the Tsallis' nonextensive statistical mechanics[3]. ... More
Nonhomogeneous Cooling, Entropic Gravity and MOND TheorySep 24 2010Jun 20 2011In this paper, by using the holographic principle, a modified equipartition theorem where we assume that below a critical temperature the energy is not equally divided on all bits, and the Unruh temperature, we derive MOND theory and a modified Friedmann ... More
Gauging by Stückelberg field-shifting symmetryMay 14 2003Aug 13 2003We embed second class constrained systems by a formalism that combines concepts of the BFFT method and the unfixing gauge formalism. As a result, we obtain a gauge-invariant system where the introduction of the Wess-Zumino (WZ) field is essential. The ... More
The Gauge Unfixing Formalism and the Solutions of the Dirac Bracket CommutatorsApr 29 2009Sep 04 2009We propose a systematic procedure that solves the Dirac bracket commutators. The method is based on the Gauge Unfixing formalism, a procedure that converts second class systems into first class ones without the enlargement of the original phase space ... More
Moduli of Legendrian CurvesOct 29 2009We construct the generic component of the moduli space of the germs of Legendrian curves with generic plane projection topologicaly equivalent to a curve y^n = x^m, (n,m)=1.
Theory of tangential idealizers and tangentially free idealsAug 06 2009Jun 20 2017We generalize the theory of logarithmic derivations through a self-contained study of modules here dubbed tangential idealizers. We establish reflexiveness criteria for such modules, provided the ring is a factorial domain. As a main consequence, necessary ... More
Magnon squeezing in an antiferromagnet: reducing the spin noise below the standard quantum limitNov 13 2003At absolute zero temperature, thermal noise vanishes when a physical system is in its ground state, but quantum noise remains as a fundamental limit to the accuracy of experimental measurements. Such a limitation, however, can be mitigated by the formation ... More
Charge stripe order from antiphase spin spirals in the spin-Fermion modelSep 21 2006We revisit the ground state of the spin-Fermion model within a semiclassical approximation. We demonstrate that antiphase spin spirals, or pi-spirals, whose chirality alternates between consecutive rows (or columns) of local moments, have, for sufficiently ... More
The Carbon New AgeMar 23 2010Graphene has been considered by many as a revolutionary material with electronic and structural properties that surpass conventional semiconductors and metals. Due to its superlative qualities, graphene is being considered as the reference material for ... More
Superconducting phase coherence in striped cupratesFeb 19 1997May 01 1997We study the problem of phase coherence in doped striped cuprates. We assume the stripes to form a network of one-dimensional Luttinger liquids which are dominated by superconducting fluctuations and pinned by impurities. The problem of phase coherence ... More
Luttinger Stripes in AntiferromagnetsNov 19 1996We propose a model for the physics of stripes in antiferromagnets in which the stripes are described by Luttinger liquids hybridized with antiferromagnetic domains. Using bosonization techniques we study the model in the limit where the magnetic correlation ... More
Landau theory of phase separation in cupratesOct 03 1994I discuss the problem of phase separation in cuprates from the point of view of the Landau theory of Fermi liquids. I calculate the rate of growth of unstable regions for the hydrodymanics and collisionless limit and, in presence of long range Coulomb ... More
Theory of tangential idealizers and tangentially free idealsAug 06 2009Oct 07 2009We generalize the theory of logarithmic derivations through a self-contained study of modules here dubbed tangential idealizers. We establish reflexiveness criteria for such modules, provided the ring is a factorial domain. As a main consequence, necessary ... More
f(R) gravity with torsion and Lorentz violationMar 10 2017The Lounesto spinor classification is an important tool in fundamental physics, because it makes explicit the pleiade of spinors types, beyond the used in quantum field theory (QFT). In this work, we show how the classification emerges in two topics: ... More
Nonlinear Pendulum: A Simple GeneralizationJul 22 2010In this work we solve the nonlinear second order differential equation of the simple pendulum with a general initial angular displacement ($\theta(0)=\theta_0$) and velocity ($\dot{\theta}(0)=\phi_0$), obtaining a closed-form solution in terms of the ... More
Removing the Wess Zumino fields in the BFFT formalismNov 29 2004Jun 09 2005In this paper we give some prescriptions in order to remove the Wess Zumino fields of the BFFT formalism and, consequently, we derive a gauge invariant system written only in terms of the original second class phase space variables. Here, the Wess Zumino ... More
A Note in the Skyrme Model with Higher Derivative TermsFeb 09 1994Another stabilizer term is used in the classical Hamiltonian of the Skyrme Model that permits in a much simple way the generalization of the higher-order terms in the pion derivative field. Improved numerical results are obtained.
Building Function Approximators on top of Haar Scattering NetworksApr 09 2018In this article we propose building general-purpose function approximators on top of Haar Scattering Networks. We advocate that this architecture enables a better comprehension of feature extraction, in addition to its implementation simplicity and low ... More
Generative Models for Stochastic Processes Using Convolutional Neural NetworksJan 09 2018The present paper aims to demonstrate the usage of Convolutional Neural Networks as a generative model for stochastic processes, enabling researchers from a wide range of fields (such as quantitative finance and physics) to develop a general tool for ... More
On the topology of families of isolated singularitiesNov 27 2014Dec 03 2014We study the topology of analytic families of $n$-dimensional complex hypersurfaces having an isolated singularity at the origin. We prove that such a family is $\mu$-constant if and only if it admits an uniform Milnor radius, which happens if and only ... More
Lê's polyhedron for line singularitiesFeb 05 2012Nov 27 2014We study the topology of a line singularity, which is a complex hypersurface with non-isolated singularity given by a complex line. We describe the degeneration of its Milnor fibre to the singular hypersurface by means of a pair of polyhedra, one in the ... More
Non-Fermi liquid behavior in U and Ce intermetallicsNov 06 1999Dec 06 1999In this paper we review the current experimental and theoretical situation of the description of non-Fermi liquid behavior (NFL) in U and Ce intermetallics. We focus on the magnetic and thermodynamic properties. We also discuss a recent theoretical interpretation ... More
Stripes, Vibrations and SuperconductivityFeb 15 2001Mar 20 2001We propose a model of a spatially modulated collective charge state of superconducting cuprates. The regions of higher carrier density (stripes) are described in terms of Luttinger liquids and the regions of lower density as a two-dimensional interacting ... More
A Many-Core Overlay for High-Performance Embedded Computing on FPGAsAug 21 2014In this work, we propose a configurable many-core overlay for high-performance embedded computing. The size of internal memory, supported operations and number of ports can be configured independently for each core of the overlay. The overlay was evaluated ... More
NON-POLYNOMIAL LAGRANGIANS IN THE SKYRME MODELApr 03 1995We choose three different coupling constants for a particular higher-derivative term in the Skyrme model that allows the total Lagrangian to converge in a binomial, geometric and a logarithmic form. Improved numerical results are obtained.
Remarks on the Collective Quantization of the SU(2) Skyrme ModelJan 03 1994We point out the question of ordering momentum operator in the canonical \break quantization of the SU(2) Skyrme Model. Thus, we suggest a new definition for the momentum operator that may solve the infrared problem that appears when we try to minimize ... More
On Stable Hypersurfaces with Vanishing Scalar CurvatureMay 24 2013Jan 07 2015We will prove that \emph{there are no stable complete hypersurfaces of $\mathbb{R}^4$ with zero scalar curvature, polynomial volume growth and such that $\dfrac{(-K)}{H^3}\geq c>0$ everywhere, for some constant $c>0$}, where $K$ denotes the Gauss-Kronecker ... More
Inhomogeneous Hopf-Oleĭnik Lemma and Applications. Part IV: Sharp Krylov Boundary Gradient Type Estimates for Solutions to Fully Nonlinear Differential Inequalities with unbounded coefficients and $C^{1,Dini}$ boundary dataAug 08 2016In this paper we provide another application of the Inhomogeneous Hopf-Ole\u{i}nik Lemma (IHOL) proved in \cite{BM-IHOL-PartI}. As a matter of fact, we also provide a new and simpler proof of IHOL with unbounded coefficients but only for the the fully ... More
Numerical renormalization group algorithms for self-similar solutions of partial differential equationsJul 18 2017Jul 10 2018We systematically study a numerical procedure that reveals the asymptotically self-similar dynamics of solutions of partial differential equations (PDEs). This procedure, based on the renormalization group (RG) theory for PDEs, appeared initially in a ... More
Glueball Regge trajectories from gauge/string duality and the PomeronJul 06 2005Dec 29 2005The spectrum of light baryons and mesons has been reproduced recently by Brodsky and Teramond from a holographic dual to QCD inspired in the AdS/CFT correspondence. They associate fluctuations about the AdS geometry with four dimensional angular momenta ... More
A Summary Description of the A2RD ProjectAug 26 2018Sep 06 2018This paper describes the Autonomous Architecture Over Restricted Domains project. It begins with the description of the context upon which the project is focused, and in the sequence describes the project and implementation models. It finish by presenting ... More
Selected Topics in Graphene physicsApr 19 2010Graphene research is currently one of the largest fields in condensed matter. Due to its unusual electronic spectrum with Dirac-like quasiparticles, and the fact that it is a unique example of a metallic membrane, graphene has properties that have no ... More
CDW, Superconductivity and Anomalous Metallic Behavior in 2D Transition Metal DichalcogenidesDec 08 2000We propose a theory for quasi-two-dimensional transition metal dichalcogenides that provides a unified microscopic picture of the charge density wave (CDW) and superconducting phases. We show, based on the electron-phonon coupling and Fermi surface topology, ... More
Non-Linear Waves in Fermi LiquidsDec 09 1994I show that when non-linearities are taken into account the Landau theory of Fermi liquids predicts the existence of hyperbolic waves in fermionic systems. The zero sound is described by a infinite set of coupled non-linear partial differential equations, ... More
An improved Gauge Unfixing formalism and the Abelian Pure Chern Simons TheorySep 29 2006Jul 05 2007We propose a variant scheme of the Gauge Unfixing formalism which modifies directly the original phase space variables of a constrained system. These new variables are gauge invariant quantities. We apply our procedure in a mixed constrained system that ... More
Using instrumental variables to disentangle treatment and placebo effects in blinded and unblinded randomized clinical trials influenced by unmeasured confoundersJun 15 2016Jun 21 2016Clinical trials traditionally employ blinding as a design mechanism to reduce the influence of placebo effects. In practice, however, it can be difficult or impossible to blind study participants and unblinded trials are common in medical research. Here ... More
Strong correlations and the anisotropy of acceptor states in insulating La(2-x)Sr(x)CuO(4)Dec 15 2010We use the Green's function formalism to discuss the role of strong correlations to the spatial structure of acceptor states doped into a two-dimensional Mott-Hubbard antiferromagnetic insulator. When the scattering between doped carriers, at the nesting ... More
From cool pions to the chiral phase transitionMar 12 2000Using the ideas of effective field theory and dimensional reduction, we relate the parameters of two low energy models of QCD: the O(N) nonlinear sigma model in D=3+1, which describes the dynamics of cool pions, and the O(N) Heisenberg magnet in D=3+0, ... More
Stability of constant mean curvature surfaces in three dimensional warped product manifoldsMar 07 2018In this paper we prove that stable, compact without boundary, oriented, constant mean curvature surfaces in the de Sitter-Schwarzschild and Reissner-Nordstrom manifolds are the slices, provided its mean curvature satisfies some lower bound. More generally, ... More
Limits of Tangents of SurfacesNov 25 2015We compute the limit of tangents of an arbitrary surface. We obtain as a byproduct an embedded version of Jung's desingularization theorem for surface singularities with finite limits of tangents.
Dynamical Casimir effect with $δ-δ^{\prime}$ mirrorsJan 22 2016Nov 01 2016We calculate the spectrum and the total rate of created particles for a real massless scalar field in $1+1$ dimensions, in the presence of a partially transparent moving mirror simulated by a Dirac $\delta-\delta^{\prime}$ point interaction. We show that, ... More
Holographic model for charmonium dissociationSep 15 2017Oct 12 2017We present a holographic bottom up model for the thermal behavior of $ c \bar c$ vector mesons in a finite temperature and density plasma. There is a clear physical interpretation for the three imput energy parameters of the model. Two of them are related ... More
Theoretical Foundations of the A2RD Project: Part IAug 27 2018Aug 30 2018This article identifies and discusses the theoretical foundations that were considered in the design of the A2RD model. In addition to the points considered, references are made to the studies available and considered in the approach.
Conditional entropy of glueball statesSep 05 2016The conditional entropy of glueball states is calculated using a holographic description. Glueball states are represented by a supergravity dual picture, consisting of a 5-dimensional graviton-dilaton action of a dynamical holographic AdS/QCD model. The ... More
Casimir force between $δ-δ^{\prime}$ mirrors transparent at high frequenciesJul 21 2016Aug 14 2016We investigate, in the context of a real massless scalar field in $1+1$ dimensions, models of partially reflecting mirrors simulated by Dirac $\delta-\delta^{\prime}$ point interactions. In the literature, these models do not exhibit full transparency ... More
Decay Properties of the Connectivity for Mixed Long Range Percolation Models on $\Z^d$May 15 2006Sep 10 2007In this short note we consider mixed short-long range independent bond percolation models on $\Z^{k+d}$. Let $p_{uv}$ be the probability that the edge $(u,v)$ will be open. Allowing a $x,y$-dependent length scale and using a multi-scale analysis due to ... More
Flux and spectral variations of 1E${\thinspace}$1740.7$-$2942 over the years 2003$-$2012Jan 14 2015The black hole system 1E${\thinspace}$1740.7$-$2942 is usually the brightest hard X-ray source (above 20 keV) near the Galactic Center, but presents some epochs of low emission (below the INTEGRAL detection limit, for example). In this work, we present ... More
Asymptotics for Nonlinear Integral Equations with Generalized Heat Kernel and Time Dependent Coefficients Using Renormalization Group TechniqueAug 11 2017In this paper we employ the Renormalization Group (RG) method to study the long-time asymptotics of a class of nonlinear integral equations with a generalized heat kernel and with time-dependent coefficients. The nonlinearities are classified and studied ... More
The Orbital Period of the Accreting Pulsar GX1+4Oct 04 1999We report strong evidence for a ~304-day periodicity in the spin history of the accretion-powered pulsar GX1+4 that is most probably associated with the orbital period of the system. We have used data from the Burst and Transient Source Experiment on ... More
Measurement of the ortho-positronium confinement energy in mesoporous thin filmsJan 12 2010May 03 2010In this paper, we present measurements of the ortho-positronium emission energy in vacuum from mesoporous films using the time of flight technique. We show evidence of quantum mechanical confinement in the mesopores that defines the minimal energy of ... More
Deformations of Legendrian CurvesJul 11 2016We construct versal and equimultiple versal deformations of the parametrization of a Legendrian curve.
On the classification of noncompact steady quasi-Einstein manifold with vanishing condition on the Weyl tensorSep 21 2017Oct 03 2017The aim of this paper is to study complete (noncompact) steady $m$-quasi-Einstein manifolds satisfying a fourth-order vanishing condition on the Weyl tensor. In this case, we are able to prove that a steady $m$-quasi-Einstein manifold ($m>1$) on a simply ... More
Finite Field-Energy and Interparticle Potential in Logarithmic ElectrodynamicsDec 18 2013We pursue an investigation of Logarithmic Electrodynamics, for which the field-energy of a point-like charge is finite, as it happens in the case of the usual Born-Infeld electrodynamics. We also show that, contrary to the latter, Logarithmic Electrodynamics ... More
Hamiltonian embedding of the massive Yang-Mills theory and the generalized Stückelberg formalismJan 16 1997May 06 1997Using the general notions of Batalin, Fradkin, Fradkina and Tyutin to convert second class systems into first class ones, we present a gauge invariant formulation of the massive Yang-Mills theory by embedding it in an extended phase space. The infinite ... More
Rigid Local Systems and Weighted Homogeneous CurvesSep 13 2014We introduce a notion of rigid local system on the comple- ment of a plane curve $Y$, which relies on a canonical Waldhausen de- composition of the Milnor sphere associated to $Y$. We show that when $Y$ is weigthed homogeneous this notion is deeply related ... More
ON THE EQUIVALENCE AMONG SOME CHIRAL-BOSON THEORIESMay 16 1995We make a comparative study of chiral-boson theories in the Florenani-Jackiw (FJ) and linear constraint formulations. A special attention is given to the case with an improved way of implementing the linear constraint. We show that it has the same spectrum ... More
BV QUANTIZATION OF A VECTOR-TENSOR GAUGE THEORY WITH TOPOLOGICAL COUPLINGMay 16 1995We use the BV quantization method for a theory with coupled tensor and vector gauge fields through a topological term. We consider in details the reducibility of the tensorial sector as well as the appearance of a mass term in the effective vectorial ... More
BFT Quantization of Chiral-Boson TheoriesAug 05 1994We use the method due to Batalin, Fradkin and Tyutin (BFT) for the quantization of chiral boson theories. We consider the Floreanini-Jackiw (FJ) formulation as well as others with linear constraints.
Isoperimetric inequalities and monotonicity formulas for submanifolds in warped product manifoldsJul 26 2016In this paper we first prove some linear isoperimetric inequalities for submanifolds in the de Sitter-Schwarzchild and Reissner-Nordstrom manifolds. Moreover, the equality is attained. Next, we prove some monotonicity formulas for submanifolds with bounded ... More
Tidal fields on braneworldsJun 09 2006We write out the geodesic deviations that take place in a $d\geq 4$ dimensional brane world subspace of a higher dimensional spacetime by splitting out the brane and the extra space dynamical quantities from a global metric spacetime of dimension $D\geq ... More
Maximum-size antichains in random set-systemsApr 21 2014Nov 12 2015We show that, for $pn \to \infty$, the largest set in a $p$-random sub-family of the power set of $\{1, \ldots, n\}$ containing no $k$-chain has size $( k - 1 + o(1) ) p \binom{n}{n/2}$ with high probability. This confirms a conjecture of Osthus, and ... More
Forest-Fire Model with Resistant TreesFeb 09 2011Aug 02 2011The role of forest heterogeneity in the long-term, large-scale dynamics of forest fires is investigated by means of a cellular automata model and mean field approximation. Heterogeneity was conceived as trees (or acres of forest) with distinct strengths ... More