Equivariant Yamabe problem and Hebey-Vaugon conjecture

In their study of the Yamabe problem in the presence of isometry group, Hebey and Vaugon announced a conjecture. This conjecture generalizes Aubin’s conjecture, which has already been proven and is sufficient to solve the Yamabe problem. In this paper, we generalize Aubin’s theorem and we prove the Hebey–Vaugon conjecture in some new cases.