 |
Universität Augsburg
|
|
|
Universität Augsburg
|
|
M. Sc. Giulia Morelli
Ludwig-Maximilians-Universität München
spricht am
Montag, 20. Oktober 2025
um
16 Uhr s.t.
im
Raum 2004 (L1)
über das Thema:
| Abstract: |
| Consider a smooth closed oriented four-manifold, its period map assigns to a Riemannian metric the space of self-dual harmonic 2-forms. This map is from the space of metrics to the Grassmannian of maximal positive subspaces in the second cohomology, where positivity is defined by the cup product. In this thesis, following "Metric stretching and the period map for smooth 4-manifolds" by Scaduto, we show that the period map has a dense image for every four-manifold, and that it is surjective if b^+=1. We also show surjectivity for manifolds which admit Ricci-flat metrics (four-torus and K3 surfaces). The proofs here involve, on one hand, the construction of families of metrics constructed by stretching along various hypersurfaces and, on the other, the properties of a specific subset of metrics on the manifolds considered. |
| Hierzu ergeht herzliche Einladung. |
| Prof. Dr. Bernhard Hanke |
Kaffee, Tee und Gebäck eine halbe Stunde vor Vortragsbeginn im Raum 2006 (L1).