Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Structure in Complexity Theory Annual Conference

On bounded round multiprover interactive proof systems

J. Cai, Anne Condon, R.J. Lipton

Published Dec 4, 2002• 16 citations
Publisher

Abstract

Bounded round multiprover interactive proof systems (MIPs) are compared with unbounded round interactive proof systems (IPSs). It is shown that for any constant epsilon , any language accepted by an unbounded round IPS has a bounded round, two-prover MIP that has error probability epsilon , resolving an open problem of L. Fortnow et al. (1988). To obtain this result, it is shown that a certain one-round MIP that simulates the computation of an unbounded round IPS can be executed many times in parallel to significantly reduce its probability of error.>

DOI
10.1109/sct.1990.113953

Related papers

PSPACE is provable by two provers in one round

Jin‐Yi Cai, Anne Condon, R.J. Lipton

It is shown that every language in PSPACE, or equivalently every language accepted by an unbounded round interactive proof system, has a one-round, two-prover interactive proof with exponentially small error probability. To obtain this result, the correctness of a simple but powerful method for parallelizing two-prover interactive proofs to reduce their error is proved.>

Structure in Complexity Theory Annual Conference•Dec 10, 2002•18 citations

Error reduction by parallel repetition-the state of the art

Uriel Feige

We show that no fixed number of parallel repetitions suffices in order to reduce the error in two-prover one-round proof systems from one constant to another. Our results imply that the recent bounds proven by Ran Raz, showing that the number of rounds that suffice is inversely proportional to the answer length, are nearly best possible. Our proof technique builds upon an idea of Oleg Verbitsky. We use this opportunity to survey the known results on parallel repetition, and to present the proofs of some previously claimed theorems. 1 Introduction A two prover one round proof system [8], MIP(2,1), is a protocol by which two provers jointly try to convince a computationally limited probabilistic verifier that a common input belongs to a prespecified language. The verifier selects a pair of questions at random. Each prover sees only one of the two questions, and sends back an answer. The verifier evaluates a predicate on the common input and the two questions and answers, and accepts or ...

•Nov 1, 1995•22 citations

NEEXP is Contained in MIP

Anand Natarajan, John Wright

We study multiprover interactive proof systems. The power of classical multiprover interactive proof systems, in which the provers do not share entanglement, was characterized in a famous work by Babai, Fortnow, and Lund (Computational Complexity 1991), whose main result was the equality MIP = NEXP. The power of quantum multiprover interactive proof systems, in which the provers are allowed to share entanglement, has proven to be much more difficult to characterize. The best known lower-bound on MIP* is NEXP ⊆ MIP* due to Ito and Vidick (FOCS 2012). As for upper bounds, MIP* could be as large as RE, the class of recursively enumerable languages. The main result of this work is the inclusion NEEXP = NTIME[22poly(n)] ⊆ MIP*. This is an exponential improvement over the prior lower bound and shows that proof systems with entangled provers are at least exponentially more powerful than classical provers. In our protocol the verifier delegates a classical, exponentially large MIP protocol for NEEXP to two entangled provers: the provers obtain their exponentially large questions by measuring their shared state, and use a classical PCP to certify the correctness of their exponentially-long answers. For the soundness of our protocol, it is crucial that each player should not only sample its own question correctly but also avoid performing measurements that would reveal the other player's sampled question. We ensure this by commanding the players to perform a complementary measurement, relying on the Heisenberg uncertainty principle to prevent the forbidden measurements from being performed.

Annual Symposium on Foundations of Computer Science•Nov 1, 2019•19 citations

NEEXP in MIP*

Anand Natarajan, Wright, John

We study multiprover interactive proof systems. The power of classical multiprover interactive proof systems, in which the provers do not share entanglement, was characterized in a famous work by Babai, Fortnow, and Lund (Computational Complexity 1991), whose main result was the equality MIP = NEXP. The power of quantum multiprover interactive proof systems, in which the provers are allowed to share entanglement, has proven to be much more difficult to characterize. The best known lower-bound on MIP* is NEXP, due to Ito and Vidick (FOCS 2012). As for upper bounds, MIP* could be as large as RE, the class of recursively enumerable languages. The main result of this work is the inclusion of NEEXP (nondeterministic doubly exponential time) in MIP*. This is an exponential improvement over the prior lower bound and shows that proof systems with entangled provers are at least exponentially more powerful than classical provers. In our protocol the verifier delegates a classical, exponentially large MIP protocol for NEEXP to two entangled provers: the provers obtain their exponentially large questions by measuring their shared state, and use a classical PCP to certify the correctness of their exponentially-long answers. For the soundness of our protocol, it is crucial that each player should not only sample its own question correctly but also avoid performing measurements that would reveal the other player's sampled question. We ensure this by commanding the players to perform a complementary measurement, relying on the Heisenberg uncertainty principle to prevent the forbidden measurements from being performed.

arXiv:1904.05870•Apr 11, 2019•8 citations

Two-prover one-round proof systems

Uriel Feige, László Lovász

We characterize the power of two-prover one-round (MIP(2,1)) proof systems, showing that MIP(2,1)=NEXPTIME. However, the following intriguing question remains open: Does parallel repetition decrease the error probability of MIP(2,1) proof systems?.

ACM Symposium on Theory of Computing (STOC)•Jan 1, 1992•161 citations

A Parallel Repetition Theorem

Ran Raz

We show that a parallel repetition of any two-prover one-round proof system (MIP(2,1)) decreases the probability of error at an exponential rate. No constructive bound was previously known. The constant in the exponent (in our analysis) depends only on the original probability of error and on the total number of possible answers of the two provers. The dependency on the total number of possible answers is logarithmic, which was recently proved to be almost the best possible [U. Feige and O. Verbitsky, Proc.11th Annual IEEE Conference on Computational Complexity, IEEE Computer Society Press, Los Alamitos, CA, 1996, pp. 70--76].

SIAM Journal on Computing•Jan 1, 1998•703 citations
Bounded round multiprover interactive proof systems (MIPs) are compared with unbounded round interactive proof systems (IPSs). It is shown that for any constant epsilon , any language accepted by an unbounded round IPS has a bounded round, two-prover MIP that has error probability epsilon , resolving an open problem of L. Fortnow et al. (1988). To obtain this result, it is shown that a certain one-round MIP that simulates the computation of an unbounded round IPS can be executed many times in parallel to significantly reduce its probability of error.>
We show that no fixed number of parallel repetitions suffices in order to reduce the error in two-prover one-round proof systems from one constant to another. Our results imply that the recent bounds proven by Ran Raz, showing that the number of rounds that suffice is inversely proportional to the answer length, are nearly best possible. Our proof technique builds upon an idea of Oleg Verbitsky. We use this opportunity to survey the known results on parallel repetition, and to present the proofs of some previously claimed theorems. 1 Introduction A two prover one round proof system [8], MIP(2,1), is a protocol by which two provers jointly try to convince a computationally limited probabilistic verifier that a common input belongs to a prespecified language. The verifier selects a pair of questions at random. Each prover sees only one of the two questions, and sends back an answer. The verifier evaluates a predicate on the common input and the two questions and answers, and accepts or ...
We study multiprover interactive proof systems. The power of classical multiprover interactive proof systems, in which the provers do not share entanglement, was characterized in a famous work by Babai, Fortnow, and Lund (Computational Complexity 1991), whose main result was the equality MIP = NEXP. The power of quantum multiprover interactive proof systems, in which the provers are allowed to share entanglement, has proven to be much more difficult to characterize. The best known lower-bound on MIP* is NEXP ⊆ MIP* due to Ito and Vidick (FOCS 2012). As for upper bounds, MIP* could be as large as RE, the class of recursively enumerable languages. The main result of this work is the inclusion NEEXP = NTIME[22poly(n)] ⊆ MIP*. This is an exponential improvement over the prior lower bound and shows that proof systems with entangled provers are at least exponentially more powerful than classical provers. In our protocol the verifier delegates a classical, exponentially large MIP protocol for NEEXP to two entangled provers: the provers obtain their exponentially large questions by measuring their shared state, and use a classical PCP to certify the correctness of their exponentially-long answers. For the soundness of our protocol, it is crucial that each player should not only sample its own question correctly but also avoid performing measurements that would reveal the other player's sampled question. We ensure this by commanding the players to perform a complementary measurement, relying on the Heisenberg uncertainty principle to prevent the forbidden measurements from being performed.
We study multiprover interactive proof systems. The power of classical multiprover interactive proof systems, in which the provers do not share entanglement, was characterized in a famous work by Babai, Fortnow, and Lund (Computational Complexity 1991), whose main result was the equality MIP = NEXP. The power of quantum multiprover interactive proof systems, in which the provers are allowed to share entanglement, has proven to be much more difficult to characterize. The best known lower-bound on MIP* is NEXP, due to Ito and Vidick (FOCS 2012). As for upper bounds, MIP* could be as large as RE, the class of recursively enumerable languages. The main result of this work is the inclusion of NEEXP (nondeterministic doubly exponential time) in MIP*. This is an exponential improvement over the prior lower bound and shows that proof systems with entangled provers are at least exponentially more powerful than classical provers. In our protocol the verifier delegates a classical, exponentially large MIP protocol for NEEXP to two entangled provers: the provers obtain their exponentially large questions by measuring their shared state, and use a classical PCP to certify the correctness of their exponentially-long answers. For the soundness of our protocol, it is crucial that each player should not only sample its own question correctly but also avoid performing measurements that would reveal the other player's sampled question. We ensure this by commanding the players to perform a complementary measurement, relying on the Heisenberg uncertainty principle to prevent the forbidden measurements from being performed.
We show that a parallel repetition of any two-prover one-round proof system (MIP(2,1)) decreases the probability of error at an exponential rate. No constructive bound was previously known. The constant in the exponent (in our analysis) depends only on the original probability of error and on the total number of possible answers of the two provers. The dependency on the total number of possible answers is logarithmic, which was recently proved to be almost the best possible [U. Feige and O. Verbitsky, Proc.11th Annual IEEE Conference on Computational Complexity, IEEE Computer Society Press, Los Alamitos, CA, 1996, pp. 70--76].