Mathematical systems theory

, Volume 10, Issue 1, pp 19–32

Relativization of questions about log space computability

  • Richard E. Ladner
  • Nancy A. Lynch


A notion of log space Turing reducibility is introduced. It is used to define relative notions of log space,A, and nondeterministic log space,. These classes are compared with the classes and which were originally defined by Baker, Gill, and Solovay [BGS]. It is shown that there exists a computable setA such that. Furthermore, there exists a computable setA such that and. Also a notion of log space truth table reducibility is defined and shown to be equivalent to the notion of log space Turing reducibility.


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Copyright information

© Springer-Verlag New York Inc. 1976

Authors and Affiliations

  • Richard E. Ladner
    • 1
  • Nancy A. Lynch
    • 2
  1. 1.Department of Computer ScienceUniversity of WashingtonSeattleUSA
  2. 2.Department of MathematicsUniversity of Southern CaliforniaLos AngelesUSA

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