• DocumentCode
    3359038
  • Title

    On reductions of NP sets to sparse sets

  • Author

    Homer, Steven ; Longpré, Luc

  • Author_Institution
    Dept. of Comput. Sci., Boston Univ., MA, USA
  • fYear
    1991
  • fDate
    30 Jun-3 Jul 1991
  • Firstpage
    79
  • Lastpage
    88
  • Abstract
    M. Ogiwara and O. Watanabe (1990) showed that if SAT is bounded truth-table reducible to a sparse set, then P=NP. In the present work, the authors simplify their proof, strengthen the result, and use it to obtain several new results. Among the new results are the following: applications of the main theorem to log-truth-table and log-Turing reductions of NP sets to sparse sets; generalizations of the main theorem which yield results similar to the main result at arbitrary levels of the polynomial hierarchy; and the construction of an oracle relative to which PNP but there are NP-complete sets which are f(n)-tt-reducible to a tally set, for any f(n)∈Ω(log n)
  • Keywords
    Turing machines; computational complexity; set theory; NP-complete sets; P≠NP; P=NP; SAT; bounded truth-table reducible; log-Turing reductions; log-truth-table; oracle; polynomial hierarchy; sparse sets; tally set; Complexity theory; Computer science; Educational institutions; Encoding; History; Internet; Polynomials;
  • fLanguage
    English
  • Publisher
    ieee
  • Conference_Titel
    Structure in Complexity Theory Conference, 1991., Proceedings of the Sixth Annual
  • Conference_Location
    Chicago, IL
  • Print_ISBN
    0-8186-2255-5
  • Type

    conf

  • DOI
    10.1109/SCT.1991.160246
  • Filename
    160246