We present a general parallel-repetition theorem with an efficient reduction. As a corollary of this theorem we establish that parallel repetition reduces the soundness error at an exponential rate in any public-coin argument, and more generally, any argument where the verifier’s messages, but not necessarily its decision to accept or reject, can be efficiently simulated with noticeable probability.
['Johan Håstad', 'Rafael Pass', 'Douglas Wikström', 'Krzysztof Pietrzak']
An efficient parallel repetition theorem