Some remarks on polynomial time isomorphisms
Joseph and Young [JY-85] hypothesized that the Berman-Hartmanis isomorphism conjecture fails if there exists a k-completely creative set in NP with no p-invertible p-completely productive functions. We verify this hypothesis for DEXT based on new results of p-creative sets in [Wan-89]. In particular, we prove that the isomorphism conjecture for DEXT fails iff there is a p-creative set for P in DEXT with no p-invertible p-productive functions.
KeywordsPolynomial Time Turing Machine Deterministic Turing Machine Nondeterministic Turing Machine Polynomial Time Computable Function
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