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arXiv · 2609.20636

Complexity Of Output Feedback Stabilization

Amir Ali Ahmadi·Abraar Chaudhry·Ijay Narang·Yukai Tang
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Abstract

We show that unless P = NP, there cannot be a polynomial-time (or even pseudo-polynomial-time) algorithm for output feedback stabilization of a linear dynamical system with a linear controller. This settles one of the best-known open problems in control theory. The result holds in both continuous and discrete time. We also present a family of stabilizable linear dynamical systems for which no polynomial-time algorithm can write down a stabilizing controller in its standard representation.

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Amir Ali Ahmadi, Abraar Chaudhry, Ijay Narang, Yukai Tang. 2026-09-17. Complexity Of Output Feedback Stabilization. https://arxiv.org/abs/2609.20636

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