A First-Order Isomorphism Theorem

نویسندگان

  • Eric Allender
  • José L. Balcázar
  • Neil Immerman
چکیده

We show that for most complexity classes of interest, all sets complete under rstorder projections (fops) are isomorphic under rst-order isomorphisms. That is, a very restricted version of the Berman-Hartmanis Conjecture holds. Since \natural" complete problems seem to stay complete via fops, this indicates that up to rst-order isomorphism there is only one \natural" complete problem for each \nice" complexity class.

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عنوان ژورنال:
  • SIAM J. Comput.

دوره 26  شماره 

صفحات  -

تاریخ انتشار 1993