Cupping and noncupping in the enumeration degrees of ∑20 sets

Annals of Pure and Applied Logic 82 (3):317-342 (1996)
  Copy   BIBTEX

Abstract

We prove the following three theorems on the enumeration degrees of ∑20 sets. Theorem A: There exists a nonzero noncuppable ∑20 enumeration degree. Theorem B: Every nonzero Δ20enumeration degree is cuppable to 0′e by an incomplete total enumeration degree. Theorem C: There exists a nonzero low Δ20 enumeration degree with the anticupping property

Links

PhilArchive



    Upload a copy of this work     Papers currently archived: 89,703

External links

Setup an account with your affiliations in order to access resources via your University's proxy server

Through your library

Similar books and articles

A hierarchy for the plus cupping Turing degrees.Yong Wang & Angsheng Li - 2003 - Journal of Symbolic Logic 68 (3):972-988.
Noncappable enumeration degrees below 0'e. [REVIEW]S. Barry Cooper & Andrea Sorbi - 1996 - Journal of Symbolic Logic 61 (4):1347 - 1363.
Limit lemmas and jump inversion in the enumeration degrees.Evan J. Griffiths - 2003 - Archive for Mathematical Logic 42 (6):553-562.
Bounded enumeration reducibility and its degree structure.Daniele Marsibilio & Andrea Sorbi - 2012 - Archive for Mathematical Logic 51 (1-2):163-186.
On the definable ideal generated by the plus cupping c.e. degrees.Wei Wang & Decheng Ding - 2007 - Archive for Mathematical Logic 46 (3-4):321-346.
Goodness in the enumeration and singleton degrees.Charles M. Harris - 2010 - Archive for Mathematical Logic 49 (6):673-691.
Badness and jump inversion in the enumeration degrees.Charles M. Harris - 2012 - Archive for Mathematical Logic 51 (3-4):373-406.
On the Symmetric Enumeration Degrees.Charles M. Harris - 2007 - Notre Dame Journal of Formal Logic 48 (2):175-204.
Sets of generators and automorphism bases for the enumeration degrees.Andrea Sorbi - 1998 - Annals of Pure and Applied Logic 94 (1-3):263-272.

Analytics

Added to PP
2014-01-16

Downloads
20 (#649,013)

6 months
3 (#434,103)

Historical graph of downloads
How can I increase my downloads?

References found in this work

Theory of Recursive Functions and Effective Computability.Hartley Rogers - 1971 - Journal of Symbolic Logic 36 (1):141-146.
Reducibility and Completeness for Sets of Integers.Richard M. Friedberg & Hartley Rogers - 1959 - Zeitschrift fur mathematische Logik und Grundlagen der Mathematik 5 (7-13):117-125.
Reducibility and Completeness for Sets of Integers.Richard M. Friedberg & Hartley Rogers - 1959 - Mathematical Logic Quarterly 5 (7‐13):117-125.

View all 19 references / Add more references