A formula for the subdifferential of the sum of a series of convex functions defined on a Banach space was provided by X. Y. Zheng in 1998. In this paper, besides a slight extension to locally convex spaces of Zheng's results, we provide a formula for the conjugate of a countable sum of convex functions. Then we use these results for calculating the subdifferentials and the conjugates in two situations related to entropy minimization, and we study a concrete example met in Statistical Physics.

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

Constantin Zălinescu

University Alexandru Ioan Cuza, Faculty of Mathematics, 700506 Iaşi, Romania
and: Institute of Mathematics O. Mayer, Romanian Academy of Sciences, Iaşi, Romania

zalinesc@uaic.ro
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C. Vallée, C. Zălinescu. “Series of Convex Functions: Subdifferential, Conjugate and Applications to Entropy Minimization.” Journal of Convex Analysis 23 (2016), No. 4, 1137–1160. https://doi.org/10.68381/jca23042