Symmetry groups of non-simply-connected four-manifolds
Abstract
Let be a closed, connected, orientable topological four-manifold with nontrivial and free abelian, , and . We show that if is a finite group of 2-rank which admits a homologically trivial, locally linear, effective action on , then must be cyclic. With additional assumptions to ensure orientability of some components of the singular set (e.g. if acts by symplectic symmetries, or preserving a spin structure), we also rule out actions. The proofs use equivariant cohomology, localization, and a careful study of the first cohomology groups of the (potential) singular set.
Cite
@article{arxiv.0707.3835,
title = {Symmetry groups of non-simply-connected four-manifolds},
author = {Michael McCooey},
journal= {arXiv preprint arXiv:0707.3835},
year = {2013}
}
Comments
16 pages. An earlier version erroneously asserted that surfaces fixed by certain involutions were orientable, and that error invalidated a later proof. This version discusses the problem and corrects the error