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On the complement of one complexity class in another

  • Diana Schmidt
Section I: Complexity
Part of the Lecture Notes in Computer Science book series (LNCS, volume 171)

Abstract

We investigate the diagonalization theorems in [7] (Theorem 23), [3] (Theorem 6) and [10] (main Theorem) and show that they can be strengthened so as to be applicable to most complexity classes, not just to those closed under polynomial-time reducibility. Thus the applications in [7], [3] and [10] (e.g. PPNP\P is not recursively presentable) are not peculiar to P, NP, PSPACE etc.; rather, they are examples of properties common to almost all "reasonable" complexity classes.

Keywords

Turing Machine Complexity Class Regular Language Finite Variation Polynomial Hierarchy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1984

Authors and Affiliations

  • Diana Schmidt
    • 1
  1. 1.Institut für Informatik I, Zirkel 275 Karlsruhe 1Federal Republic of Germany

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