Proximal calculus on Riemannian manifolds, with applications to fixed point theory
arXiv:math/0403465
Abstract
We introduce a proximal subdifferential and develop a calculus for nonsmooth functions defined on any Riemannian manifold . We give several applications of this theory, concerning: 1) differentiability and geometrical properties of the distance function to a closed subset of ; 2) solvability and implicit function theorems for nonsmooth functions on ; 3) conditions on the existence of a circumcenter for three different points of ; and especially 4) fixed point theorems for expansive and nonexpansive mappings and certain perturbations of such mappings defined on .
27 pages