Now showing items 41-60 of 230

    • Quantum electrodynamics in external fields from the spin representation 

      Gracia Bondía, José M.; Várilly Boyle, Joseph C. (1994-07)
      Systematic use of the infinite-dimensional spin representation simplifies and rigorizes several questions in quantum field theory. This representation permutes "Gaussian" elements in the fermion Fock space, and is necessarily ...
    • The metaplectic representation and boson fields 

      Gracia Bondía, José M.; Várilly Boyle, Joseph C. (1991-12)
      We construct explicitly the infinite-dimensional metaplectic representation and show how its use simplifies and rigorizes several questions in bosonic Quantum Field Theory. The representation permutes Gaussian elements in ...
    • Finite Element Methods for Large-Strain Poroelasticity/Chemotaxis Models Simulating the Formation of Myocardial Oedema 

      Barnafi Wittwer, Nicolás Alejandro; Gómez Vargas, Bryan Andrés; Lourenço, Wesley De Jesus; Reis, Ruy Freitas; Rocha, Bernardo Martins; Lobosco, Marcelo; Ruiz Baier, Ricardo; Weber dos Santos, Rodrigo (2022-07-22)
      In this paper we propose a novel coupled poroelasticity-diffusion model for the formation of extracellular oedema and infectious myocarditis valid in large deformations, manifested as an interaction between interstitial ...
    • Noncommutative geometry and quantization 

      Várilly Boyle, Joseph C. (2000-06)
      We examine some recent developments in noncommutative geometry, including spin geometries on noncommutative tori and their quantization by the Shale-Stinespring procedure, as well as the emergence of Hopf algebras as a ...
    • On the ultraviolet behaviour of quantum fields over noncommutative manifolds 

      Várilly Boyle, Joseph C.; Gracia Bondía, José M. (1999-03)
      By exploiting the relation between Fredholm modules and the Segal-Shale-Stinespring version of canonical quantization, and taking as starting point the first-quantized fields described by Connes' axioms for noncommutative ...
    • Connes' tangent groupoid and strict quantization 

      Cariñena Marzo, José F.; Clemente Gallardo, Jesús; Follana, Eduardo; Gracia Bondía, José M.; Rivero, Alejandro; Várilly Boyle, Joseph C. (1999-12)
      We address one of the open problems in quantization theory recently listed by Rieffel. By developing in detail Connes' tangent groupoid principle and using previous work by Landsman, we show how to construct a strict flabby ...
    • A nonperturbative form of the spectral action principle in noncommutative geometry 

      Figueroa González, Héctor; Gracia Bondía, José M.; Lizzi, Fedele; Várilly Boyle, Joseph C. (1998-07)
      Using the formalism of superconnections, we show the existence of a bosonic action functional for the standard K-cycle in noncommutative geometry, giving rise, through the spectral action principle, only to the Einstein ...
    • Faà di Bruno Hopf algebras 

      Figueroa González, Héctor; Gracia Bondía, José M.; Várilly Boyle, Joseph C. (2022-11)
      This is a short review on the Faà di Bruno formulas, implementing composition of real-analytic functions, and a Hopf algebra associated to such formulas. This structure allows, among several other things, a short proof of ...
    • On summability of distributions and spectral geometry 

      Estrada Navas, Ricardo; Gracia Bondía, José M.; Várilly Boyle, Joseph C. (1998-01)
      Modulo the moment asymptotic expansion, the Cesàro and parametric behaviours of distributions at infinity are equivalent. On the strength of this result, we construct the asymptotic analysis for spectral densities arising ...
    • From geometric quantization to Moyal quantization 

      Gracia Bondía, José M.; Várilly Boyle, Joseph C. (1995-06)
      We show how the Moyal product of phase-space functions, and the Weyl correspondence between symbols and operator kernels, may be obtained directly using the procedures of geometric quantization, applied to the symplectic ...
    • Modeling the university drinking culture phenomenon 

      Serracín Morales, Alisson; Herrera Garro, César; Sánchez Peña, Fabio Ariel (2022-11-03)
      We study a susceptible-drinker-recovered (SDR) model for the drinking culture phenomenon in university atmospheres. We find conditions for this model to have extinction and endemic equilibrium points. We analyze different ...
    • Analysis of a vorticity–based fully–mixed formulation for 3D Brinkman–Darcy problem. 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2016)
      We propose and analyze a fully-mixed finite element method to numerically approximate the flow patterns of a viscous fluid within a highly permeable medium (an array of low concentration fixed particles), described by ...
    • A basic model for the propagation of ideologies 

      Mata Boschini, Luis Diego; Salas Jiménez, Eduardo; Sánchez Peña, Fabio Ariel (2022-11)
      Ideas and ideologies move the world and are involved in almost every aspect of human life and society. This paper presents a mathematical model for the propagation of two different ideologies in a group of people that could ...
    • The Impact of Help-Seeking for Depression: A Mathematical Model 

      Aguilar Álvarez, Daniel; Sáenz, Josúe A.; Sánchez Peña, Fabio Ariel (2022)
      For years and with the Covid-19 pandemic, mental illnesses such as depression have emerged. According to the World Health Organization, an average of 5\% of the population in a country suffers from depression. The ...
    • A mixed-primal finite element approximation of a sedimentation–consolidation system 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2016)
      This paper is devoted to the mathematical and numerical analysis of a strongly cou- pled flow and transport system typically encountered in continuum-based models of sedimentation–consolidation processes. The model focuses ...
    • Relativistic quantum kinematics in the Moyal representation 

      Cariñena Marzo, José F.; Gracia Bondía, José M.; Várilly Boyle, Joseph C. (1990-03)
      In this paper, we obtain the phase-space quantization for relativistic spinning particles. The main tool is what we call a "Stratonovich-Weyl quantizer" which relates functions on phase space to operators on a suitable ...
    • An augmented mixed–primal finite element method for a coupled flow–transport problem 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2015)
      In this paper we analyze the coupling of a scalar nonlinear convection-diffusion problem with the Stokes equations where the viscosity depends on the distribution of the solution to the transport problem. An augmented ...
    • A posteriori error analysis of a fully-mixed formulation for the Brinkman–Darcy problem 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2017-09-05)
      We develop the a posteriori error analysis for a mixed finite element method applied to the coupling of Brinkman and Darcy equations in 3D, modelling the interaction of viscous and non-viscous flow effects across a given ...
    • Aposteriori error estimation for an augmented mixed-primal method applied to sedimentation–consolidation systems 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2018-08-15)
      In this paper we develop the aposteriorierror analysis of an augmented mixed-primal finite element method for the 2D and 3D versions of a stationary flow and transport coupled system, typically encountered in sedimentati ...
    • A mixed-primal finite element method for the coupling of Brinkman-Darcy flow and nonlinear transport. 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2021-01)
      This paper is devoted to the mathematical and numerical analysis of a model describing the interfacial flow-transport interaction in a porous-fluidic domain. The medium consists of a highly permeable material, where the ...