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arXiv · 2611.03945

The Complexity of KKT Points of Quadratic Programs with Polynomially-Bounded Coefficients

Argyrios Deligkas·Michail Fasoulakis·Stavros D. Ioannidis
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Abstract

Computing a Karush-Kuhn-Tucker (KKT) point of a quadratic polynomial over the unit hypercube is known to be $CLS$-complete, when the coefficients of the polynomial are encoded in binary. We prove that the problem remains $CLS$-complete even when the coefficients are encoded in unary. This is the first problem proven to remain $CLS$-hard when the input is given in unary.

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Argyrios Deligkas, Michail Fasoulakis, Stavros D. Ioannidis. 2026-11-02. The Complexity of KKT Points of Quadratic Programs with Polynomially-Bounded Coefficients. https://arxiv.org/abs/2611.03945

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