## Journal of Symbolic Logic

### An almost-universal cupping degree

#### Abstract

Say that an incomplete d.r.e. degree has almost universal cupping property, if it cups all the r.e. degrees not below it to 0'. In this paper, we construct such a degree d, with all the r.e. degrees not cupping d to 0' bounded by some r.e. degree strictly below d. The construction itself is an interesting 0''' argument and this new structural property can be used to study final segments of various degree structures in the Ershov hierarchy.

#### Article information

Source
J. Symbolic Logic, Volume 76, Issue 4 (2011), 1137-1152.

Dates
First available in Project Euclid: 11 October 2011

https://projecteuclid.org/euclid.jsl/1318338843

Digital Object Identifier
doi:10.2178/jsl/1318338843

Mathematical Reviews number (MathSciNet)
MR2895390

Zentralblatt MATH identifier
1247.03077

#### Citation

Liu, Jiang; Wu, Guohua. An almost-universal cupping degree. J. Symbolic Logic 76 (2011), no. 4, 1137--1152. doi:10.2178/jsl/1318338843. https://projecteuclid.org/euclid.jsl/1318338843

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