Automorphisms of Drinfeld's half-spaces over a finite field

School of Mathematics Colloquium
Thursday, March 6, 2014 - 11:00am for 1 hour (actually 50 minutes)
Skiles 006
Annette Werner – Johann Wolfgang Goethe-Universit├Ąt (Frankfurt)
Joseph Rabinoff
Drinfeld's upper half-spaces over non-archimedean local fields are the founding examples of the theory of period domains. In this talk we consider analogs of Drinfeld's upper half-spaces over finite fields. They are open subvarieties of a projective space. We show that their automorphism group is the group of automorphisms of the ambient projective space. This is a problem in birational geometry, which we solve using tools in non-archimedean analytic geometry.