Virtual Localization in equivariant Witt cohomology

Abstract

We prove an analog of the virtual localization theorem of Graber-Pandharipande, in the setting of an action by the normalizer of the torus in ${\text{SL}}_2$, and with the Chow groups replaced by the cohomology of a suitably twisted sheaf of Witt groups.

More ackground on six-functors was added. New sections on independence of choice of models and on changing the group for equivariant Borel-Moore homology was added. Additional details added to some proofs. To appear Indagationes Math. volume for Jacob Murre