An almost deep degree
- 1 June 2001
- journal article
- Published by Cambridge University Press (CUP) in The Journal of Symbolic Logic
- Vol. 66 (2) , 881-901
- https://doi.org/10.2307/2695051
Abstract
We show there is a non-recursive r.e. set A such that if W is any low r.e. set. then the join W ⊕ A is also low. That is. A is “almost deep”. This answers a question of Joekusch. The almost deep degrees form an definable ideal in the r.e. degrees (with jump.)Keywords
This publication has 1 reference indexed in Scilit:
- The Decidability of the Existential Theory of the Poset of Recursively Enumerable Degrees with Jump RelationsAdvances in Mathematics, 1996