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: 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 Journal of Formal Logic 38 (1997), no. 3, 406--418. doi:10.1305/ndjfl/1039700747. http://projecteuclid.org/euclid.ndjfl/1039700747.


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