Quantum Computers Can Find Quadratic Nonresidues in Deterministic Polynomial Time

Thomas G. Draper

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arXiv · 2106.03991

Quantum Computers Can Find Quadratic Nonresidues in Deterministic Polynomial Time

Thomas G. Draper

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Abstract

An integer $a$ is a quadratic nonresidue for a prime $p$ if $x^2 \equiv a \bmod p$ has no solution. Quadratic nonresidues may be found by probabilistic methods in polynomial time. However, without assuming the Generalized Riemann Hypothesis, no deterministic polynomial-time algorithm is known. We present a quantum algorithm which generates a random quadratic nonresidue in deterministic polynomial time.

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Thomas G. Draper. 2021-06-07. Quantum Computers Can Find Quadratic Nonresidues in Deterministic Polynomial Time. https://arxiv.org/abs/2106.03991

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