Some Progress in Conformal Geometry

Sun-Yung A. Chang ; Jie Qing ; Paul Yang

Symmetry, integrability and geometry: methods and applications, Tome 3 (2007)

Résumé

This is a survey paper of our current research on the theory of partial differential equations in conformal geometry. Our intention is to describe some of our current works in a rather brief and expository fashion. We are not giving a comprehensive survey on the subject and references cited here are not intended to be complete. We introduce a bubble tree structure to study the degeneration of a class of Yamabe metrics on Bach flat manifolds satisfying some global conformal bounds on compact manifolds of dimension 4. As applications, we establish a gap theorem, a finiteness theorem for diffeomorphism type for this class, and diameter bound of the $\sigma _2$-metrics in a class of conformal 4-manifolds. For conformally compact Einstein metrics we introduce an eigenfunction compactification. As a consequence we obtain some topological constraints in terms of renormalized volumes.

Détail

Keywords: Bach flat metrics; bubble tree structure; degeneration of metrics; conformally compact; Einstein; renormalized volume.

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