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arXiv · 2610.25524

Breaking the 1/3 Barrier for Approximate Nash Equilibria in Symmetric Bimatrix Games

Ashkan Soleymani·Patrick Jaillet·Gabriele Farina
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Abstract

We give the first unconditional family of polynomial-time algorithms that breaks the $1/3$ approximation barrier for symmetric bimatrix games. For every fixed $δ>0$, an algorithm in this family computes a symmetric $(1-1/\sqrt{2}+δ)$-approximate Nash equilibrium, improving on the previous best guarantee of $(1/3+δ)$ due to Kontogiannis and Spirakis [2011].

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Ashkan Soleymani, Patrick Jaillet, Gabriele Farina. 2026-10-18. Breaking the 1/3 Barrier for Approximate Nash Equilibria in Symmetric Bimatrix Games. https://arxiv.org/abs/2610.25524

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