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arXiv · 2608.24832

Certified Randomness without Structure Against Shallow-Query Adversaries

Dakshita Khurana·Bhaskar Roberts·Avishay Tal
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Abstract

In a recent breakthrough, Yamakawa and Zhandry (J. ACM 2024) constructed a proof of quantumness in the quantum random oracle model (QROM) in which the quantum prover samples a codeword preimage of a publicly computable function H. They conjectured that given any H, a successful prover must sample their preimage from a high-entropy distribution over possible answers. If true, this would give a certifiable randomness protocol in the quantum random oracle model. As partial evidence for their conjecture, Yamakawa and Zhandry proved the security of their certifiable randomness protocol assuming the Aaronson-Ambainis conjecture. We prove the security of the certifiable randomness protocol of Yamakawa-Zhandry unconditionally, without relying on the unproven Aaronson-Ambainis conjecture, against low query-depth quantum adversaries: specifically, adversaries that make up to o(\log \lambda) adaptive quantum queries to the random oracle.

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Dakshita Khurana, Bhaskar Roberts, Avishay Tal. 2026-08-25. Certified Randomness without Structure Against Shallow-Query Adversaries. https://arxiv.org/abs/2608.24832

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