Sökning: "David Rydh"
Visar resultat 1 - 5 av 8 avhandlingar innehållade orden David Rydh.
1. Families of cycles and the Chow scheme
Sammanfattning : The objects studied in this thesis are families of cycles on schemes. A space — the Chow variety — parameterizing effective equidimensional cycles was constructed by Chow and van der Waerden in the first half of the twentieth century. Even though cycles are simple objects, the Chow variety is a rather intractable object. LÄS MER
2. Building Data for Stacky Covers and the Étale Cohomology Ring of an Arithmetic Curve : Du som saknar dator/datorvana kan kontakta [email protected] för information
Sammanfattning : This thesis consists of two papers with somewhat different flavours. In Paper I we compute the étale cohomology ring H^*(X,Z/nZ) for X the ring of integers of a number field K. As an application, we give a non-vanishing formula for an invariant defined by Minhyong Kim. LÄS MER
3. Stacky Modifications and Operations in the Étale Cohomology of Number Fields
Sammanfattning : This thesis consists of 4 papers. In Paper A we define stacky building data for stacky covers in the spirit of Pardini and give an equivalence of (2,1)- categories between the category of stacky covers and the category of stacky building data. LÄS MER
4. Computations in the Grothendieck Group of Stacks
Sammanfattning : 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. LÄS MER
5. Destackification and Motivic Classes of Stacks
Sammanfattning : This thesis consists of three articles treating topics in the theory of algebraic stacks. The first two papers deal with motivic invariants. In the first, we show that the class of the classifying stack BPGLn is the inverse of the class of PGLn in the Grothendieck ring of stacks for n ≤ 3. LÄS MER
