Post-quantum Zero Knowledge in Constant Rounds

TL;DR

This paper presents a constant-round zero-knowledge protocol for NP that remains secure against quantum attacks, utilizing quantum encryption primitives and introducing a novel simulation technique.

Contribution

It introduces the first constant-round zero-knowledge protocol for NP secure against quantum adversaries, based on quantum fully-homomorphic encryption and a new no-cloning simulation method.

Findings

Secure against quantum attacks under standard assumptions

Achieves constant-round zero-knowledge for NP and QMA

Introduces a novel no-cloning non-black-box simulation technique

Abstract

We construct a constant-round zero-knowledge classical argument for NP secure against quantum attacks. We assume the existence of Quantum Fully-Homomorphic Encryption and other standard primitives, known based on the Learning with Errors Assumption for quantum algorithms. As a corollary, we also obtain a constant-round zero-knowledge quantum argument for QMA. At the heart of our protocol is a new no-cloning non-black-box simulation technique.