Stratifications of Reductions of Shimura Varieties
by
Torsten Wedhorn
University of Cologne

In many cases Shimura varieties can be considered as moduli spaces of abelian varieties with additional structures and this description allows the definition of integral models. One of the main techniques to study these models and related arithmetical questions is to stratify the special fibre. The goal of this talk is to describe some of these stratifications: Many of their properties (e.g. number of strata, their specialization, their dimension) are related to data which can be stated in terms of the reductive group which defines the Shimura variety and hence can be described by purely combinatorial notions.

http://www.mi.uni-koeln.de/~wedhorn

Date received: February 27, 2001