Pseudofinite groups as fixed points in simple groups of finite Morley rank

We prove that if the group of fixed points of a generic automorphism of a simple group of finite Morley rank is pseudofinite, then this group is an extension of a (twisted) Chevalley group over a pseudofinite field. On the way to obtain this result, we classify non-abelian definably simple pseudofinite groups of finite centralizer dimension (using the ideas of Wilson (1993) [29]). (c) 2012 Elsevier B.V. All rights reserved.