Subject: A question for the mailing list From: "Boccellari" Date: Thu, 15 Jun 2006 21:46:32 +0200 my question is not strictly for algebraic topologists, nevertheless I try to submit it to your mailing list. Let N be a smooth manifold, g and h two Riemannian structures on it, and f : N ----> N a smooth. If f is homotopic to the identity and harmonic with respect to g on the domain and h on the codomain is it a diffeomorphism? In dimension two and for N compact with non positive sectional curvature it is true, but for higher dimension? I will be grateful for both a direct answer and a reference. Thank you for your kind attention. Tommaso Boccellari