If deterministic and nondeterministic space complexities are equal for log log n then they are also equal for log n

  • Andrzej Szepietowski
Contributed Papers Complexity 2
Part of the Lecture Notes in Computer Science book series (LNCS, volume 349)


It is well known that for any „well behaved“ space function L(n) ≥ log n if DSPACE(L(n)) = NSPACE(L(n)) then also DSPACE(H(n)) = NSPACE(H(n)) for all „well behaved“ functions H(n) ≥ L(n). The aim of this paper is to show that also if DSPACE(log log n) = NSPACE(log log n) then L = NL (i.e. DSPACE(log n) = NSPACE(log n)).


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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • Andrzej Szepietowski
    • 1
  1. 1.Mathematical DepartmentTechnical University of GdańskGdańskPoland

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