Journal of Symbolic Logic

The Theory of the Recursively Enumerable Weak Truth-Table Degrees is Undecidable

Klaus Ambos-Spies, Andre Nies, and Richard A. Shore

Full-text is available via JSTOR, for JSTOR subscribers. Go to this article in JSTOR.

Abstract

We show that the partial order of $\Sigma^0_3$-sets under inclusion is elementarily definable with parameters in the semilattice of r.e. wtt-degrees. Using a result of E. Herrmann, we can deduce that this semilattice has an undecidable theory, thereby solving an open problem of P. Odifreddi.

Article information

Source
J. Symbolic Logic, Volume 57, Issue 3 (1992), 864-874.

Dates
First available in Project Euclid: 6 July 2007

Permanent link to this document
https://projecteuclid.org/euclid.jsl/1183744045

Mathematical Reviews number (MathSciNet)
MR1187453

Zentralblatt MATH identifier
0776.03020

JSTOR
links.jstor.org

Citation

Ambos-Spies, Klaus; Nies, Andre; Shore, Richard A. The Theory of the Recursively Enumerable Weak Truth-Table Degrees is Undecidable. J. Symbolic Logic 57 (1992), no. 3, 864--874. https://projecteuclid.org/euclid.jsl/1183744045


Export citation