Parallel Repetition for Post-Quantum Arguments

Andrew Huang; Yael Tauman Kalai

Paper 2025/1027

Parallel Repetition for Post-Quantum Arguments

Andrew Huang

, Massachusetts Institute of Technology

Yael Tauman Kalai, Massachusetts Institute of Technology

Abstract

In this work, we show that parallel repetition of public-coin interactive arguments reduces the soundness error at an exponential rate even in the post-quantum setting. Moreover, we generalize this result to hold for threshold verifiers, where the parallel repeated verifier accepts if and only if at least $t$ of the executions are accepted (for some threshold $t$). Prior to this work, these results were known only when the cheating prover was assumed to be classical. We also prove a similar result for three-message private-coin arguments. Previously, Bostanci, Qian, Spooner, and Yuen (STOC 2024) proved such a parallel repetition result in the more general setting of quantum protocols, where the verifier and communication may be quantum. We consider only protocols where the verifier is classical, but obtain a simplified analysis, and for the more general setting of threshold verifiers.

Metadata

Available format(s): PDF
Category: Foundations
Publication info: Preprint.
Contact author(s): ahuang @ mit edu
tauman @ mit edu
History: 2025-06-15: revised; 2025-06-02: received; See all versions
Short URL: https://ia.cr/2025/1027
License: CC BY

BibTeX

@misc{cryptoeprint:2025/1027,
      author = {Andrew Huang and Yael Tauman Kalai},
      title = {Parallel Repetition for Post-Quantum Arguments},
      howpublished = {Cryptology {ePrint} Archive, Paper 2025/1027},
      year = {2025},
      url = {https://eprint.iacr.org/2025/1027}
}