We prove that every proper convex and lower semicontinuous functional Φ defined on a real reflexive Banach space X is semicoercive if and only if every small uniform perturbation of Φ attains its minimum value on X.

Contact details are reproduced from the original publication and may be historical.

Samir Adly

LACO, Université de Limoges, 123 Avenue A. Thomas, 87060 Limoges, France

Emil Ernst

Institute of Mathematics, Romanian Academy of Sciences, 70700 Bucharest, Romania

Michel Théra

Université de Limoges, 123 Avenue A. Thomas, 87060 Limoges, France

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S. Adly, E. Ernst, M. Théra. “A Characterization of Convex and Semicoercive Functionals.” Journal of Convex Analysis 8 (2001), No. 1, 127–148. https://doi.org/10.68381/jca08006