Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10118918 | Annals of Pure and Applied Logic | 2005 | 17 Pages |
Abstract
We study the minimal enumeration degree (e-degree) problem in models of fragments of Peano arithmetic (PA) and prove the following results: in any model M of Σ2 induction, there is a minimal enumeration degree if and only if M is a nonstandard model. Furthermore, any cut in such a model has minimal e-degree. By contrast, this phenomenon fails in the absence of Σ2 induction. In fact, whether every Σ2 cut has minimal e-degree is independent of the Σ2 bounding principle.
Related Topics
Physical Sciences and Engineering
Mathematics
Logic
Authors
M.M. Arslanov, C.T. Chong, S.B. Cooper, Y. Yang,