Search for dissertations about: "Torsten Ekedahl"

Showing result 1 - 5 of 6 swedish dissertations containing the words Torsten Ekedahl.

  2. 1. Computations in the Grothendieck Group of Stacks

    Author : Daniel Bergh; Torsten Ekedahl; David Rydh; Jochen Heinloth; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematics; matematik;

    Abstract : Given an algebraic group, one may consider the class of its classifying stackin the Grothendieck group of stacks. This is an invariant studied byEkedahl. For certain connected groups, called the special groups bySerre and Grothendieck, the invariant simply gives the inverse of the class ofthe group itself. READ MORE

  4. 2. Minimal models in algebra, combinatorics and topology

    Author : Alexander Berglund; Torsten Ekedahl; Alexandru Suciu; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK; matematik; Mathematics;

    Abstract : The thesis consists of seven papers.In Paper I, II, III, IV and V, we study homological invariants of monomial rings — rings of the form R = k[x1, . . . READ MORE

  5. 3. Grothendieck Rings and Motivic Integration

    Author : Karl Rökaeus; Torsten Ekedahl; Johannes Nicaise; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK; matematik; Mathematics;

    Abstract : This thesis consists of three parts: In Part I we study the Burnside ring of the finite group G. This ring has a natural structure of a lambda-ring. However, a priori the images of the G-set S under the lambda-operations can only be computed recursively. READ MORE

  6. 4. Intersections on moduli spaces of curves

    Author : Sergei Shadrin; Torsten Ekedahl; Carel Faber; Stockholms universitet; []
    Keywords : Mathematics;

    Abstract : We present a new approach to perform calculations with the certain standard classes in cohomology of the moduli spaces of curves. It is based on an important lemma of Ionel relating the intersection theoriy of the moduli space of curves and that of the space of admissible coverings. READ MORE

  7. 5. The Theory of Polynomial Functors

    Author : Qimh Xantcha; Torsten Ekedahl; Vincent Franjou; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; numerical ring; polynomial map; strict polynomial map; numerical map; polynomial functor; strict polynomial functor; numerical functor; maze; multi-set; multation; Algebra and geometry; Algebra och geometri; Mathematics; matematik;

    Abstract : Polynomial functors were introduced by Professors Eilenberg and Mac Lane in 1954, who used them to study certain homology rings. Strict polynomial functors were invented by Professors Friedlander and Suslin in 1997, in order to develop the theory of group schemes. READ MORE