Professor Alessandro Portaluri
Montag, 28. Mai 2018
Raum 2004 (L1)
über das Thema:
|A celebrated result due to Poincaré asserts that a closed minimizing geodesic on an oriented surface is linearly unstable when considered an orbit of the co-geodesic flow. In this talk, starting from this classical theorem, we discuss some recently new results on the instability and hyperbolicity of closed (maybe not minimizing) geodesics of any causal character on higher dimensional (even not oriented) semi-Riemannian manifolds. Dropping the non-positivity assumption of the metric tensor is a quite challenging task since the Morse index is truly infinite. This is a joint work with Xijun Hu and Ran Yang.|
|Hierzu ergeht herzliche Einladung.|
Kaffee, Tee und Gebäck eine halbe Stunde vor Vortragsbeginn im Raum 2006 (L1).