Abstract
In this paper, we define the prox-regularity for functions on Banach spaces by adapting the original definition in R n. In this context, we establish a subdifferential characterization and show that qualified convexly C 1,+-composite functions and primal lower nice functions belong to this class, as already known in the setting of Hilbert spaces. We also study, in a geometrical point of view, the epigraphs of prox-regular functions. The subdifferential characterization allows us to show that some Moreau-envelope-like regularizations of such functions are of class C 1 in the context of certain uniformly convex spaces.
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Bernard, F., Thibault, L. Prox-Regularity of Functions and Sets in Banach Spaces. Set-Valued Analysis 12, 25–47 (2004). https://doi.org/10.1023/B:SVAN.0000023403.87092.a2
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DOI: https://doi.org/10.1023/B:SVAN.0000023403.87092.a2