Now showing items 1-15 of 15

  • An ellipsoidal billiard with a quadratic potential 

    Fedorov, Yuri (2003)
    Article
    Open Access
    There exists an in infite hierarchy of integrable generalizations of the geodesic flow on an n -di- mensional ellipsoid.hese generalizations describe the motion of a point in the force fields of certain polynomial potentials.In ...
  • Closed Geodesics and Billiards on Quadrics related to elliptic KdV solutions 

    Abenda, Simonetta; Fedorov, Yuri (2004)
    Article
    Open Access
    We consider algebraic geometrical properties of the integrable billiard on a quadric Q with elastic impacts along another quadric confocal to Q. These properties are in sharp contrast with those of the ellipsoidal Birkho® ...
  • Extension of maps defined on many fibres 

    Barja Yáñez, Miguel Ángel; Naranjo, J. C. (1997)
    Article
    Open Access
    Let S be a fibred surface. We prove that the existence of morphisms from non countably many fibres to curves implies, up to base change, the existence of a rational map from S to another surface fibred over the same base ...
  • Moduli spaces and formal operads 

    Guillén Santos, Francisco; Navarro, Vicenç (Navarro Aznar); Pascual Gainza, Pere; Roig Martí, Agustín (2003)
    Article
    Open Access
    Let Mg,l be the moduli space of stable algebraic curves of genus g with l marked points. With the operations which relate the different moduli spaces identifying marked points, the family (Mg,l)g,l is a modular operad ...
  • Multiplier ideals of plane curves 

    Dachs Cadefau, Ferran (Universitat Politècnica de Catalunya, 2012-10)
    Master thesis
    Restricted access - author's decision
    Multiplier ideals and their corresponding jumping numbers have been revealed as a fundamental tool to measure the singularity of plane curves. There are approaches to these objects from both Commutative Algebra and Algebraic ...
  • On the slope of bielliptic fibrations 

    Barja Yáñez, Miguel Ángel (1997)
    Article
    Open Access
    Let $\pi :S\longrightarrow B$ be a bielliptic fibration. We prove $S$ is, up to base change, a rational double cover of an elliptic fibration and that $\pi $ is isotrivial provided it is smooth. Finally, we prove that the ...
  • On the slope of fibred surfaces 

    Barja Yáñez, Miguel Ángel; Zucconi, Franco (1998)
    Article
    Open Access
  • On the Torelli problem and Jacobian Nullwerte in genus three 

    Guàrdia Rubies, Jordi (2008)
    Article
    Open Access
    We give a closed formula for recovering a non-hyperelliptic genus three curve from its period matrix, and derive some identities between Jacobian Nullwerte in dimension three.
  • Optimizations in the computation of pairings and cryptographic applications 

    Sánchez Charles, David (Universitat Politècnica de Catalunya, 2013-07)
    Master thesis
    Open Access
    En la criptografía de clave pública actual el uso de curvas elípticas es cada vez más habitual debido a que ofrecen una seguridad similar a los ya utilizados cuerpos finitos, pero con unas claves más cortas. Por otra parte, ...
  • Rational parametrization of Q-curves: Sage implementatio 

    Geffner Fuenmayor, Ivan Eduardo (Universitat Politècnica de Catalunya, 2013-09)
    Bachelor thesis
    Open Access
    En aquest treball donarem una parametrització d'un tipus especial de corbes algebràiques anomenades "Q-corbes". Primer farem una introducció per familiartizar al lector amb conceptes bàsics i resultats previs, i després ...
  • Sato-Tate distributions and Galois endomorphism modules in genus 2 

    Fité, Francesc; Kedlaya, Kiran; Rotger Cerdà, Víctor; Sutherland, Andrew (2012)
    Article
    Restricted access - publisher's policy
    For an abelian surface A over a number eld k, we study the limit- ing distribution of the normalized Euler factors of the L-function of A. This distribution is expected to correspond to taking characteristic poly- nomials ...
  • Synthesis of displacement functions by Bézier curves in constant-breadth cams with parallel flat-faced translating and oscillating followers 

    Cardona Foix, Salvador; Zayas Figueras, Enrique Ernesto; Jordi Nebot, Lluïsa; Català Calderon, Pau (2013-04)
    Article
    Restricted access - publisher's policy
    The constant-breadth cam mechanisms, which drive a parallel flat-faced double follower, are desmodromic, and guarantee global bilaterality. In the said mechanisms, the law of displacement of the follower can only be freely ...
  • The structure and slope of bielliptic fibrations 

    Barja Yáñez, Miguel Ángel (1997)
    Article
    Open Access
  • Tipus de reduccions de corbes 

    Guitart Morales, Xavier (Publicacions i Edicions de la Universitat de Barcelona (UB), 2008-01-31)
    Part of book or chapter of book
    Open Access
  • Torcimiento de cuárticas planas lisas 

    Lorenzo García, Elisa (Universitat Politècnica de Catalunya, 2010-10)
    Master thesis
    Open Access
    En este trabajo se determinan los twists de las cuárticas planas lisas, es decir, de las curvas lisas no hiperelípticas de género 3. Se parte de una clasificación de Henn de las cuárticas planas y sus grupos de automorfismos ...