The Wirthmüller isomorphism revisited

We show how the formal Wirthmuller isomorphism theorem proven in (2) simplifies the proof of the Wirthmuller isomorphism in equivariant stable homotopy the- ory. Other examples from equivariant stable homotopy theory show that the hypotheses of the formal Wirthmuller and formal Grothendieck isomorphism theorems in (2) cannot be weakened.