A first-order method for nonconvex-strongly-concave constrained minimax optimization

Zhaosong Lu; Sanyou Mei

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arXiv · 2512.22909

A first-order method for nonconvex-strongly-concave constrained minimax optimization

Zhaosong Lu·Sanyou Mei

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Abstract

In this paper we study a nonconvex-strongly-concave constrained minimax problem. Specifically, we propose a first-order augmented Lagrangian method for solving it, whose subproblems are nonconvex-strongly-concave unconstrained minimax problems and suitably solved by a first-order method developed in this paper that leverages the strong concavity structure. Under suitable assumptions, the proposed method achieves an operation complexity of $O(\varepsilon^{-3.5}\log\varepsilon^{-1})$, measured in terms of its fundamental operations, for finding an $\varepsilon$-KKT solution of the constrained minimax problem, which improves the previous best-known operation complexity by a factor of $\varepsilon^{-0.5}$.

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BibTeX RIS

Zhaosong Lu, Sanyou Mei. 2025-12-28. A first-order method for nonconvex-strongly-concave constrained minimax optimization. https://arxiv.org/abs/2512.22909

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