skip to main content
10.1145/1806689.1806703acmconferencesArticle/Chapter ViewAbstractPublication PagesstocConference Proceedingsconference-collections
research-article

Hardness amplification in proof complexity

Published:05 June 2010Publication History

ABSTRACT

We present a general method for converting any family of unsatisfiable CNF formulas that is hard for one of the simplest proof systems -- tree resolution -- into formulas that require large rank in very strong proof systems, including any proof system that manipulates polynomials of degree at most k (known as Th(k) proofs). These include high degree versions of Lovasz-Schrijver and Cutting Planes proofs.

We introduce two very general families of these proof systems, denoted Tcc(k) and Rcc(k). The proof lines of Tcc(k) are arbitrary Boolean functions, each of which can be evaluated by an efficient k-party randomized communication protocol. Tcc(k) proofs include Th(k-1) proofs as a special case. Rcc(k) proofs generalize Tcc(k) proofs and require only that each inference be checkable by a short k-party protocol.

For all k in O(loglog n), our main results are as follows: First, any unsatisfiable CNF formula of high resolution rank can be efficiently transformed into another CNF formula requiring high rank in all Rcc(k) systems, and exponential tree size in all Tcc(k) systems. Secondly, there are strict rank hierarchies for all Rcc(k) systems, and strict tree-size hierarchies for all Tcc(k) systems. Finally, we apply our general method to give optimal integrality gaps for low rank Rcc(2) proofs for MAX-2t-SAT, which imply optimal integrality gaps for low rank Cutting Planes and Th(1) proofs.

References

  1. R. Beals, H. Buhrman, R. Cleve, M. Mosca, and R. de Wolf. Quantum lower bounds by polynomials. JACM, 48(4):778--797, 2001. Google ScholarGoogle ScholarDigital LibraryDigital Library
  2. P. Beame, T. Pitassi, and N. Segerlind. Lower bounds for Lovasz-Schrijver systems and beyond follow from multiparty communication complexity. SIAM J. Comput., 37(3):845--869, 2007. Google ScholarGoogle ScholarDigital LibraryDigital Library
  3. P. Beame and D.--T. Huynh--Ngoc. Multiparty communication complexity and threshold circuit size of AC0. In 50th IEEE FOCS, 53--62, 2009. Google ScholarGoogle ScholarDigital LibraryDigital Library
  4. E. Ben-Sasson and A. Wigderson. Short proofs are narrow -- resolution made simple. JACM, 48(2):149--169, 2001. Google ScholarGoogle ScholarDigital LibraryDigital Library
  5. J. Buresh-Oppenheim, N. Galesi, S. Hoory, A. Magen, and T. Pitassi. Rank bounds and integrality gaps for cutting planes procedures. In 44th IEEE FOCS, 318--327, 2003. Google ScholarGoogle ScholarDigital LibraryDigital Library
  6. J. Buresh-Oppenheim and R. Santhanam. Making hard problems harder. TR06-03, ECCC, 2006.Google ScholarGoogle Scholar
  7. M. Charikar, K. Makarychev, and Y. Makarychev. Integrality gaps for Sherali-Adams relaxations. In 41st ACM STOC, 283--292, 2009. Google ScholarGoogle ScholarDigital LibraryDigital Library
  8. A. Chattopadhyay and A. Ada. Multiparty communication complexity of disjointness. TR08-002, ECCC, 2008.Google ScholarGoogle Scholar
  9. V. Chvatal. Edmonds polytopes and a hierarchy of combinatorial problems. Discrete Mathematics, 4:305--337, 1973.Google ScholarGoogle ScholarDigital LibraryDigital Library
  10. V. Chvatal and Endre Szemeredi. Many hard examples for resolution. JACM, 35(4):759--768, 1988. Google ScholarGoogle ScholarDigital LibraryDigital Library
  11. M. Davis, G. Logemann, and D. Loveland. A machine program for theorem proving. CACM, 5:394--397, 1962. Google ScholarGoogle ScholarDigital LibraryDigital Library
  12. J. Edmonds, R. Impagliazzo, S. Rudich, and J. Sgall. Communication complexity towards lower bounds on circuit depth. Computational Complexity, 10:210--246, 2001.Google ScholarGoogle ScholarCross RefCross Ref
  13. K. Georgiou, A. Magen, T. Pitassi, and I. Tourlakis. Integrality gaps of 2-o(1) for vertex cover SDPs in the Lovasz-Schrijver hierarchy. In 48th IEEE FOCS, 702--712, 2007. Google ScholarGoogle ScholarDigital LibraryDigital Library
  14. R.E. Gomory. Outline of an algorithm for integer solutions to linear programs. Bull. of the AMS, 64:275--278, 1958.Google ScholarGoogle ScholarCross RefCross Ref
  15. D. Grigoriev. Linear lower bound on degrees of Positivstellensatz calculus proofs for the parity. TCS, 259:613--622, 2001.Google ScholarGoogle ScholarCross RefCross Ref
  16. D. Grigoriev, E. A. Hirsch, and D. V. Pasechnik. Complexity of semi-algebraic proofs. In STACS LNCS v. 2285, 419--430, 2002. Google ScholarGoogle ScholarDigital LibraryDigital Library
  17. R. Impagliazzo and R. Paturi. On the complexity of k-SAT. JCSS, 67:367--375, 2001. Google ScholarGoogle ScholarDigital LibraryDigital Library
  18. R. Impagliazzo, T. Pitassi, and A. Urquhart. Upper and lower bounds on tree-like cutting planes proofs. In 9th IEEE LICS, 220--228, 1994.Google ScholarGoogle Scholar
  19. M. Karchmer, R. Raz, and A. Wigderson. Super-logarithmic depth lower bounds via direct sum in communication complexity. Computational Complexity, 5:191--204, 1995.Google ScholarGoogle ScholarCross RefCross Ref
  20. A. Kojevnikov and A. Itsykson. Lower bounds of static Lovasz-Schrijver calculus proofs for Tseitin tautologies. In 33rd ICALP, 323--334, 2006. Google ScholarGoogle ScholarDigital LibraryDigital Library
  21. J. Krajicek. Discretely ordered modules as a first-order extension of the cutting planes proof system. JSL, 63(4):1582--1596, 1998.Google ScholarGoogle ScholarCross RefCross Ref
  22. E. Kushilevitz and N. Nisan. Communication Complexity. Cambridge University Press, 1997. Google ScholarGoogle ScholarDigital LibraryDigital Library
  23. J.B. Lasserre. An explicit SDP relaxation for nonlinear 0-1 programs. In IPCO, LNCS v. 2081, 293--303, 2001. Google ScholarGoogle ScholarDigital LibraryDigital Library
  24. T. Lee and A. Shraibman. Disjointness is hard in the multi-party number-on-the-forehead model. In 23rd IEEE CCC, 81--91, 2008. Google ScholarGoogle ScholarDigital LibraryDigital Library
  25. L. Lovasz and A. Schrijver. Cones of matrices and set-functions and 0-1 optimization. SIAM J. Optimization, 1(2):166--190, 1991.Google ScholarGoogle ScholarCross RefCross Ref
  26. A. Maciel and T. Pitassi. Lower bounds on constant-depth Frege proofs with mod connectives modulo a hardness conjecture. In 11th IEEE LICS, 189--200, 2006. Google ScholarGoogle ScholarDigital LibraryDigital Library
  27. S. Muroga. Threshold logic and its applications. John Wiley & Sons, 1971.Google ScholarGoogle Scholar
  28. N. Nisan and M. Szegedy. On the degree of boolean functions as real polynomials. Computational Complexity, 4:301--314, 1994. Google ScholarGoogle ScholarDigital LibraryDigital Library
  29. R. Raz and P. McKenzie. Separation of the monotone NC hierarchy. Combinatorica, 19(3):403--435, 1999.Google ScholarGoogle ScholarDigital LibraryDigital Library
  30. G. Schoenebeck. Linear level Lasserre lower bounds for certain k-CSPs. In 49th IEEE FOCS, 593--602, 2008. Google ScholarGoogle ScholarDigital LibraryDigital Library
  31. G. Schoenebeck, L. Trevisan, and M. Tulsiani. A linear round lower bound for Lovasz-Schrijver SDP relaxations of Vertex Cover. In 22nd IEEE CCC, 205--216, 2007. Google ScholarGoogle ScholarDigital LibraryDigital Library
  32. N. Segerlind and T. Pitassi. Exponential lower bounds and integrality gaps for tree-like Lovasz-Schrijver procedures. In ACM-SIAM SODA, 355--364, 2009. Google ScholarGoogle ScholarDigital LibraryDigital Library
  33. A. Sherali and W. Adams. A hierarchy of relaxations between the continuous and convex hull representations for zero--one programming problems. SIAM J. Disc. Math., 3:411--430, 1990. Google ScholarGoogle ScholarDigital LibraryDigital Library
  34. A. A. Sherstov. Separating AC0 from depth-2 majority circuits. In 39th ACM STOC, 294--301, 2007. Google ScholarGoogle ScholarDigital LibraryDigital Library
  35. A. A. Sherstov. The pattern matrix method for lower bounds on quantum communication. In 40th ACM STOC, 85--94, 2008. Full version: CoRR, abs/0906.4291. Google ScholarGoogle ScholarDigital LibraryDigital Library
  36. M. Tulsiani. CSP gaps and reductions in the Lasserre hierarchy. In 41st ACM STOC, 303--312, 2009. Google ScholarGoogle ScholarDigital LibraryDigital Library

Index Terms

  1. Hardness amplification in proof complexity

    Recommendations

    Comments

    Login options

    Check if you have access through your login credentials or your institution to get full access on this article.

    Sign in
    • Published in

      cover image ACM Conferences
      STOC '10: Proceedings of the forty-second ACM symposium on Theory of computing
      June 2010
      812 pages
      ISBN:9781450300506
      DOI:10.1145/1806689

      Copyright © 2010 ACM

      Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected]

      Publisher

      Association for Computing Machinery

      New York, NY, United States

      Publication History

      • Published: 5 June 2010

      Permissions

      Request permissions about this article.

      Request Permissions

      Check for updates

      Qualifiers

      • research-article

      Acceptance Rates

      Overall Acceptance Rate1,469of4,586submissions,32%

      Upcoming Conference

      STOC '24
      56th Annual ACM Symposium on Theory of Computing (STOC 2024)
      June 24 - 28, 2024
      Vancouver , BC , Canada

    PDF Format

    View or Download as a PDF file.

    PDF

    eReader

    View online with eReader.

    eReader