English

The Baillon-Haddad Theorem Revisited

Optimization and Control 2009-12-22 v2 Functional Analysis

Abstract

In 1977, Baillon and Haddad proved that if the gradient of a convex and continuously differentiable function is nonexpansive, then it is actually firmly nonexpansive. This result, which has become known as the Baillon-Haddad theorem, has found many applications in optimization and numerical functional analysis. In this note, we propose short alternative proofs of this result and strengthen its conclusion.

Cite

@article{arxiv.0906.0807,
  title  = {The Baillon-Haddad Theorem Revisited},
  author = {Heinz H. Bauschke and Patrick L. Combettes},
  journal= {arXiv preprint arXiv:0906.0807},
  year   = {2009}
}
R2 v1 2026-06-21T13:09:26.576Z