Skip to main content

Composition of Low-Error 2-Query PCPs Using Decodable PCPs

  • Chapter
Property Testing

Part of the book series: Lecture Notes in Computer Science ((LNTCS,volume 6390))

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 specific PCPs that were being composed), resulting in complicated constructions of PCPs. Furthermore, until recently, composition in the low error regime suffered 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 specific 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 verifier in addition to verifying the validity of the given proof like a standard PCP verifier, 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 full version of this paper appears in the Electronic Colloquium on Computational Complexity [DH09]. The current extended abstract is a modification of the introduction of the full version for the purposes of the ICS mini-workshop on propert testing.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 39.99
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 54.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Arora, S., Lund, C., Motwani, R., Sudan, M., Szegedy, M.: Proof verification and the hardness of approximation problems. J. ACM 45(3), 501–555 (1998); Preliminary Version in 33rd FOCS (1992), eccc: TR98-008, doi:10.1145/278298.278306

    Article  MathSciNet  MATH  Google Scholar 

  2. Arora, S., Safra, S.: Probabilistic checking of proofs: A new characterization of NP. J. ACM 45(1), 70–122 (1998), doi:10.1145/273865.273901

    Article  MathSciNet  MATH  Google Scholar 

  3. Arora, S., Sudan, M.: Improved low-degree testing and its applications. Combinatorica 23(3), 365–426 (2003); Preliminary Version in 29th STOC (1997), eccc: TR97-003, doi:10.1007/s00493-003-0025-0

    Article  MathSciNet  MATH  Google Scholar 

  4. Ben-Sasson, E., Goldreich, O., Harsha, P., Sudan, M., Vadhan, S.: Robust PCPs of proximity, shorter PCPs and applications to coding. SIAM J. Computing 36(4), 889–974 (2006); Preliminary Version in 36th STOC (2004), eccc: TR04-021, doi:10.1137/S0097539705446810

    Article  MathSciNet  MATH  Google Scholar 

  5. Bellare, M., Goldwasser, S., Lund, C., Russell, A.: Efficient probabilistically checkable proofs and applications to approximation. In: Proc. 25th ACM Symp. on Theory of Computing (STOC), pp. 294–304. ACM, New York (1993), doi:10.1145/167088.167174

    Google Scholar 

  6. Bogdanov, A.: Gap amplification fails below 1/2 (2005) (Comment on ”Dinur, The PCP theorem by gap amplification), eccc:TR05-046

    Google Scholar 

  7. Ben-Sasson, E., Sudan, M.: Short PCPs with polylog query complexity. SIAM J. Computing 38(2), 551–607 (2008); Preliminary Version in 37th STOC (2005), eccc:TR04-060, doi:10.1137/050646445

    Article  MathSciNet  MATH  Google Scholar 

  8. Dinur, I., Fischer, E., Kindler, G., Raz, R., Safra, S.: PCP characterizations of NP: Towards a polynomially-small error-probability. In: Proc. 31st ACM Symp. on Theory of Computing (STOC), pp. 29–40. ACM, New York (1999), eccc:TR98-066, doi:10.1145/301250.301265

    Google Scholar 

  9. Dinur, I., Harsha, P.: Composition of low-error 2-query PCPs using decodable PCPs. Technical Report TR09-042, Electronic Colloquium on Computational Complexity (2009), eccc:TR09-042

    Google Scholar 

  10. Dinur, I.: The PCP theorem by gap amplification. J. ACM 54(3), 12 (2007); Preliminary Version in 38th STOC (2006), eccc: TR05-046, doi:10.1145/1236457.1236459

    Article  MathSciNet  MATH  Google Scholar 

  11. Dinur, I.: PCPs with small soundness error. SIGACT News 39(3), 41–57 (2008), doi:10.1145/1412700.1412713

    Article  Google Scholar 

  12. Dinur, I., Reingold, O.: Assignment testers: Towards a combinatorial proof of the PCP Theorem. SIAM J. Computing 36, 975–1024 (2006), doi:10.1137/S0097539705446962

    Article  MathSciNet  MATH  Google Scholar 

  13. Feige, U., Goldwasser, S., Lovász, L., Safra, S., Szegedy, M.: Interactive proofs and the hardness of approximating cliques. J. ACM 43(2), 268–292 (1996); Preliminary version in 32nd FOCS (1991), doi:10.1145/226643.226652

    Article  MathSciNet  MATH  Google Scholar 

  14. Feige, U., Kilian, J.: Impossibility results for recycling random bits in two-prover proof systems. In: Proc. 27th ACM Symp. on Theory of Computing (STOC), pp. 457–468. ACM, New York (1995), doi:10.1145/225058.225183

    Google Scholar 

  15. David Forney, G.: Concatenated Codes. MIT Press, Cambridge (1966)

    MATH  Google Scholar 

  16. Håstad, J.: Some optimal inapproximability results. J. ACM 48(4), 798–859 (2001); Preliminary Version in 29th STOC (1997), doi:10.1145/502090.502098

    Article  MathSciNet  MATH  Google Scholar 

  17. Impagliazzo, R., Kabanets, V., Wigderson, A.: Direct product testing: Improved and derandomized. In: Proc. 41st ACM Symp. on Theory of Computing (STOC), pp. 131–140. ACM, New York (2009), eccc:TR09-090, doi:10.1145/1536414.1536435

    Google Scholar 

  18. Moshkovitz, D., Raz, R.: Sub-constant error probabilistically checkable proof of almost linear size (2007), eccc:TR07-026

    Google Scholar 

  19. Moshkovitz, D., Raz, R.: Sub-constant error low degree test of almost-linear size. SIAM J. Computing 38(1), 140–180 (2008); Preliminary Version in 38th STOC (2006), eccc:TR05-086, doi:10.1137/060656838

    Article  MathSciNet  MATH  Google Scholar 

  20. Moshkovitz, D., Raz, R.: Two query PCP with sub-constant error. In: Proc. 49th IEEE Symp. on Foundations of Comp. Science (FOCS), pp. 314–323. IEEE, Los Alamitos (2008), eccc:TR08-071, doi:10.1109/FOCS.2008.60

    Google Scholar 

  21. Raz, R.: A parallel repetition theorem. SIAM J. Computing 27(3), 763–803 (1998); Preliminary Version in 27th STOC (1995), doi:10.1137/S0097539795280895

    Article  MathSciNet  MATH  Google Scholar 

  22. Raz, R., Safra, S.: A sub-constant error-probability low-degree test, and a sub-constant error-probability PCP characterization of NP. In: Proc. 29th ACM Symp. on Theory of Computing (STOC), pp. 475–484. ACM, New York (1997), doi:10.1145/258533.258641

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2010 Springer-Verlag Berlin Heidelberg

About this chapter

Cite this chapter

Dinur, I., Harsha, P. (2010). Composition of Low-Error 2-Query PCPs Using Decodable PCPs. In: Goldreich, O. (eds) Property Testing. Lecture Notes in Computer Science, vol 6390. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-16367-8_21

Download citation

  • DOI: https://doi.org/10.1007/978-3-642-16367-8_21

  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-642-16366-1

  • Online ISBN: 978-3-642-16367-8

  • eBook Packages: Computer ScienceComputer Science (R0)

Publish with us

Policies and ethics