3 papers
quant-ph2026
Average-and Last-Iterate Lower Bounds for Optimistic Matrix Mirror-Prox in Quantum Zero-Sum Games
Yiheng Su, Emmanouil-Vasileios Vlatakis-Gkaragkounis, Pucheng Xiong
Optimistic matrix mirror-prox (OMMP) computes -approximate Nash equilibria in quantum zero-sum games with an average-iterate guarantee [arXiv:2311.10859]. We…
cs.CC2026
On the Complexity of Finding Fixed Points for Set-Valued Contractions
Emmanouil-Vasileios Vlatakis-Gkaragkounis, Pucheng Xiong
In this paper, we study the computational complexity of finding fixed points for set-valued contractions. We first formulate a computational problem for Nadler's fixed-point theore…
cs.GT2025
Breaking Barrier in Quantum Zero-Sum Games: Generalizing Metric Subregularity for Spectraplexes
Yiheng Su, Emmanouil-Vasileios Vlatakis-Gkaragkounis, Pucheng Xiong
Quantum zero-sum games are bilinear saddle-point problems over density matrices. We study how their semidefinite geometry governs last-iterate convergence beyond existing $O(1/\var…