### The Wirthmuller isomorphism revisited, by J.P. May

We show how the formal Wirthmuller isomorphism theorem proven in
"Isomorphisms between left and right adjoints", by Fausk, Hu, and May,
simplifies the proof of the Wirthmuller isomorphism in equivariant stable
homotopy theory. Other examples from equivariant stable homotopy theory
show that the hypotheses of the formal Wirthmuller and formal Grothendieck
isomorphism theorems in the cited paper cannot be weakened.

J.P. May <may@math.uchicago.edu>