Abstract | ||
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Abstract The main result of this paper is a,generic composition theorem for low error two-query probabilistically checkable proofs (PCPs). Prior to this work, composition of PCPs was well- understood only in the constant error regime. Existing composition methods in the low error regime were non-modular (i.e., very much tailored to the specic PCPs that were being com- posed), resulting in complicated constructions of PCPs. Furthermore, until recently, composition in the low error regime suered,from incurring an extra ‘consistency’ query, resulting in PCPs that are not ‘two-query’ and hence, much less useful for hardness-of-approximation reductions. In a recent breakthrough, Moshkovitz and Raz [In Proc. 49th IEEE Symp. on Foundations of Comp. Science (FOCS), 2008] constructed almost linear-sized low-error 2-query PCPs for every language in NP. Indeed, the main technical component of their construction is a novel composition of certain specic,PCPs. We give a modular and simpler proof of their result by repeatedly applying the new composition theorem to known PCP components. To facilitate the new modular composition, we introduce a new variant of PCP, which we call a decodable PCP (dPCP). A dPCP is an encoding of an NP witness that is both locally checkable and locally decodable. The dPCP verier,in addition to verifying the validity of the given proof like a standard PCP verier, also locally decodes the original NP witness. Our composition is generic in the sense that it works regardless of the way the component PCPs are constructed. A preliminary version of this paper appeared in the Proc. 50th IEEE Symp. on Foundations of Comp. Science |
Year | DOI | Venue |
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2013 | 10.1109/FOCS.2009.8 | Electronic Colloquium on Computational Complexity |
Keywords | Field | DocType |
specific pcps,component pcps,new composition theorem,certain specific pcps,existing composition method,novel composition,low-error 2-query pcps,decodable pcps,2-query pcps,low error regime,generic composition theorem,new modular composition,composition,probability,probabilistic logic,decoding,computational complexity,polynomials,encoding,robustness,hardness of approximation,indexes,construction industry | Discrete mathematics,Combinatorics,Polynomial,Computer science,Robustness (computer science),Mathematical proof,Probabilistic logic,Decoding methods,Modular design,Encoding (memory),Computational complexity theory | Journal |
Volume | Issue | ISSN |
42 | 6 | 0272-5428 |
ISBN | Citations | PageRank |
3-642-16366-1 | 16 | 0.60 |
References | Authors | |
27 | 2 |
Name | Order | Citations | PageRank |
---|---|---|---|
Irit Dinur | 1 | 1187 | 85.67 |
Prahladh Harsha | 2 | 371 | 32.06 |