Notre Dame Journal of Formal Logic

Infima in the Recursively Enumerable Weak Truth Table Degrees

Rich Blaylock, Rod Downey, and Steffen Lempp

Abstract

We show that for every nontrivial r.e. wtt-degree a, there are r.e. wtt-degrees b and c incomparable to a such that the infimum of a and b exists but the infimum of a and c fails to exist. This shows in particular that there are no strongly noncappable r.e. wtt-degrees, in contrast to the situation in the r.e. Turing degrees.

Article information

Source
Notre Dame J. Formal Logic Volume 38, Number 3 (1997), 406-418.

Dates
First available in Project Euclid: 12 December 2002

Permanent link to this document
http://projecteuclid.org/euclid.ndjfl/1039700747

Mathematical Reviews number (MathSciNet)
MR1624962

Digital Object Identifier
doi:10.1305/ndjfl/1039700747

Zentralblatt MATH identifier
0909.03038

Subjects
Primary: 03D30: Other degrees and reducibilities

Citation

Blaylock, Rich; Downey, Rod; Lempp, Steffen. Infima in the Recursively Enumerable Weak Truth Table Degrees. Notre Dame J. Formal Logic 38 (1997), no. 3, 406--418. doi:10.1305/ndjfl/1039700747. http://projecteuclid.org/euclid.ndjfl/1039700747.


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