# Probabilistic checking of proofs: a new characterization of NP

@article{Arora1998ProbabilisticCO, title={Probabilistic checking of proofs: a new characterization of NP}, author={Sanjeev Arora and Shmuel Safra}, journal={J. ACM}, year={1998}, volume={45}, pages={70-122} }

We give a new characterization of NP: the class NP contains exactly those languages <italic>L</italic> for which membership proofs (a proof that an input <italic>x</italic> is in <italic>L</italic>) can be verified probabilistically in polynomial time using <italic>logarithmic</italic> number of random bits and by reading <italic>sublogarithmic</italic> number of bits from the proof.
We discuss implications of this characterization; specifically, we show that approximating Clique and… Expand

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