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arXiv · 2605.00728

Sion's minimax theorem and the proximal point algorithm in Hadamard spaces

Fumiaki Kohsaka
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Abstract

We obtain Sion's minimax theorem in Hadamard spaces and discuss its applications. Among other things, we study several fundamental properties of resolvents of saddle functions in Hadamard spaces. An application to the proximal point algorithm for minimax problems in Hadamard spaces are also included.

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Fumiaki Kohsaka. 2026-05-01. Sion's minimax theorem and the proximal point algorithm in Hadamard spaces. https://arxiv.org/abs/2605.00728

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