Sökning: "Algebra and geometry"
Visar resultat 11 - 15 av 88 avhandlingar innehållade orden Algebra and geometry.
11. Rees algebras of modules and Quot schemes of points
Sammanfattning : This thesis consists of three articles. The first two concern a generalization of Rees algebras of ideals to modules. Paper A shows that the definition of the Rees algebra due to Eisenbud, Huneke and Ulrich has an equivalent, intrinsic, definition in terms of divided powers. LÄS MER
12. Vector-valued Eisenstein series of congruence types and their products
Sammanfattning : Historically, Kohnen and Zagier connected modular forms with period polynomials, and as a consequence of this association concluded that the products of at most two Eisenstein series span all spaces of classical modular forms of level 1. Later Borisov and Gunnells among other authors extended the result to higher levels. LÄS MER
13. Isomorphism classes of abelian varieties over finite fields
Sammanfattning : Deligne and Howe described polarized abelian varieties over finite fields in terms of finitely generated free Z-modules satisfying a list of easy to state axioms. In this thesis we address the problem of developing an effective algorithm to compute isomorphism classes of (principally) polarized abelian varieties over a finite field, together with their automorphism groups. LÄS MER
14. Cohomology of the moduli space of curves of genus three with level two structure
Sammanfattning : In this thesis we investigate the moduli space M3[2] of curves of genus 3 equipped with a symplectic level 2 structure. In particular, we are interested in the cohomology of this space. We obtain cohomological information by decomposing M3[2] into a disjoint union of two natural subspaces, Q[2] and H3[2], and then making S7- resp. LÄS MER
15. Multipoint Okounkov bodies
Sammanfattning : During the nineties, the field medallist Okounkov found a way to associate to an ample line bundle L over an n−complex dimensional projective manifold X a convex body in Rn, now called Okounkov body ∆(L). The construction depends on the choice of a valuation centered at one point p∈X and it works even if L is a big line bundle. LÄS MER
