On fixed point sets and Lefschetz modules for sporadic simple groups

Abstract

We consider 2-local geometries and other subgroup complexes for sporadic simple groups. For six groups, the fixed point set of a noncentral involution is shown to be equivariantly homotopy equivalent to a standard geometry for the component of the centralizer. For odd primes, fixed point sets are computed for sporadic groups having an extraspecial Sylow p-subgroup of order p^3, acting on the complex of those p-radical subgroups containing a p-central element in their centers. Vertices for summands of the associated reduced Lefschetz modules are described.

22 pages

References in corpus (3)

• Propagating sharp group homology decompositions
• New collections of p-subgroups and homology decompositions for classifying spaces of finite groups
• On fixed point sets of distinguished collections for groups of parabolic characteristic