Cohomology of graph hypersurfaces associated to certain Feynman graphs
Abstract
Description
To any Feynman graph (with 2n edges) we can associate a hypersurface X\subset\PP^{2n-1}. We study the middle cohomology H^{2n-2}(X) of such hypersurfaces. S. Bloch, H. Esnault, and D. Kreimer (Commun. Math. Phys. 267, 2006) have computed this cohomology for the first series of examples, the wheel with spokes graphs WS_n, n\geq 3. Using the same technique, we introduce the generalized zigzag graphs and prove that W_5(H^{2n-2}(X))=\QQ(-2) for all of them (with W_{*} the weight filtration). Next, we study primitively log divergent graphs with small number of edges and the behavior of graph hypersurfaces under the gluing of graphs.
111 pages, Ph.D. thesis at the University of Duisburg-Essen
111 pages, Ph.D. thesis at the University of Duisburg-Essen