We investigate the security of succinct arguments against quantum adversaries. Our main result is a proof of knowledge-soundness in the post-quantum setting for a class of multi-round interactive protocols, including those based on the recursive folding technique of Bulletproofs.
To prove this result, we devise a new quantum rewinding strategy, the first that allows for rewinding across many rounds. This technique applies to any protocol satisfying natural multi-round generalizations of special soundness and collapsing. For our main result, we show that recent Bulletproofs-like protocols based on lattices satisfy these properties, and are hence sound against quantum adversaries.
Nick Spooner is an Assistant Professor of Computer Science at the University of Warwick. His work focuses on post-quantum proof systems. His interests include interactive proof systems and zero knowledge in general, post-quantum cryptography, quantum information, coding theory and computational complexity. Previously he was a postdoc at Boston University, and he received his PhD from UC Berkeley in 2020.