报告人：Fernando Galaz-Garcia（Karlsruher Institut für Technologie）
时间：2018-10-18 10:00-11:00
地点：Room 1303, Sciences Building No. 1
Abstract: In Riemannian geometry, collapse imposes strong geometricand topological restrictions on the
spaces on which it occurs. In the case of Alexandrov spaces, which generalize Riemannian manifolds with
a lower sectioanl curvature bound, collapse is fairly well understood in dimension three. In this talk I will
discuss the topology of sufficiently collapsed Alexandrov 3-spaces: when the space is irreducible, it is
modeled on one of the eight three-dimensional dimensional Thurston geometries, excluding the
hyperbolic one. This extends a result of Shioya and Yamaguchi, originally formulated for Riemannian
manifolds, to the Alexandrov setting. This is joint work with Luis Guijarro and Jesús Núñez-Zimbrón.
