Now showing items 1-12 of 123

    • Of limit key polynomials 

      Alberich Carramiñana, Maria; Fernández Boix, Albert.; Fernández González, Julio; Guàrdia Rubies, Jordi; Nart Vinyals, Enric; Roé Vellvé, Joaquim (2021-04-01)
      Article
      Open Access
      Let ν be a valuation of arbitrary rank on the polynomial ring K[x] with coefficients in a field K. We prove comparison theorems between MacLane-Vaquié key polynomials for valuations μ ≤ν and abstract key polynomials for ...
    • The singular Weinstein conjecture 

      Miranda Galcerán, Eva; Oms, Cedric (2021-07-23)
      Article
      Open Access
      In this article, we investigate Reeb dynamics on bm-contact manifolds, previously introduced in [37], which are contact away from a hypersurface Zbut satisfy certain transversality conditions on Z. The study of these contact ...
    • On the singular Weinstein conjecture and the existence of escape orbits for b-Beltrami fields 

      Miranda Galcerán, Eva; Oms, Cedric; Peralta-Salas, Daniel (2021-07-01)
      Article
      Open Access
      Motivated by Poincaré’s orbits going to infinity in the (restricted) three-body problem, we investigate the generic existence of heteroclinic-like orbits in a neighbourhood of the critical set of a b-contact form. This is ...
    • Geometric quantization via cotangent models 

      Mir Garcia, Pau; Miranda Galcerán, Eva (2021-09)
      Article
      Open Access
      In this article we give a universal model for geometric quantization associated to a real polarization given by an integrable system with non-degenerate singularities. This universal model goes one step further than the ...
    • Discrepancies between observational data and theoretical forecast in single field slow roll inflation 

      Amorós Torrent, Jaume; Haro Cases, Jaume (2016-09-09)
      Article
      Open Access
      The PLANCK collaboration has determined, or greatly constrained, values for the spectral parameters of the CMB radiation, namely the spectral index ns, its running as, the running of the running ßs, using a growing body ...
    • Geometric quantization of almost toric manifolds 

      Miranda Galcerán, Eva; Presas, Francisco; Barbieri Solha, Romero (2020)
      Article
      Open Access
      Kostant gave a model for the geometric quantization via the cohomology associated to the sheaf of flat sections of a pre-quantum line bundle. This model is well-adapted for real polarizations given by integrable systems ...
    • Algebraic statistics in practice: applications to networks 

      Casanellas Rius, Marta; Petrovic, Sonja; Uhler, Caroline (2020-01-01)
      Article
      Open Access
      Algebraic statistics uses tools from algebra (especially from multilinear algebra, commutative algebra, and computational algebra), geometry, and combinatorics to provide insight into knotty problems in mathematical ...
    • A contact geometry framework for field theories with dissipation 

      Gaset Rifà, Jordi; Gràcia Sabaté, Francesc Xavier; Muñoz Lecanda, Miguel Carlos; Rivas Guijarro, Xavier; Román Roy, Narciso (2020-03-01)
      Article
      Open Access
      We develop a new geometric framework suitable for dealing with Hamiltonian field theories with dissipation. To this end we define the notions of k-contact structure and k-contact Hamiltonian system. This is a generalization ...
    • Unified Lagrangian-Hamiltonian formalism for contact systems 

      De León, Manuel; Gaset Rifà, Jordi; Lainz Valcázar, Manuel; Rivas Guijarro, Xavier; Román Roy, Narciso (2020-06-23)
      Article
      Open Access
      We present a unified geometric framework for describing both the Lagrangian and Hamiltonian formalisms of contact autonomous mechanical systems, which is based on the approach of the pioneering work of R. Skinner and R. ...
    • La compacitat, una noció seminal en l'evolució de la topologia general (1895-1930) 

      Moreno Montes, Júlia; Blanco Abellán, Mónica; Pascual Gainza, Pere (2020)
      Article
      Open Access
      En aquest article es revisa l'evolució de la definició d'espai topològic compacte des de la primera definició de Fréchet el 1904, que va generalitzar la propietat de Bolzano-Weierstrass, passant per la relació amb el teorema ...
    • Matter Bounce Scenario in F(T) gravity 

      Haro Cases, Jaume; Amorós Torrent, Jaume (2016)
      Article
      Open Access
      It is shown that teleparallel F(T) theories of gravity combined with holonomy corrected Loop Quantum Cosmology (LQC) support a Matter Bounce Scenario (MBS) which is a potential alternative to the inflationary paradigm. The ...
    • Viability of the Matter Bounce Scenario 

      Haro Cases, Jaume; Amorós Torrent, Jaume (Institute of Physics (IOP), 2015)
      Article
      Open Access
      It is shown that teleparallel F(T) theories of gravity combined with Loop Quantum Cosmology support a Matter Bounce Scenario which is an alternative to the inflation scenario in the Big Bang paradigm. It is checked that ...