Comparing the degrees of enumerability and the closed Medvedev degrees
Logic
2018-10-09 v2
Abstract
We compare the degrees of enumerability and the closed Medvedev degrees and find that many situations occur. There are nonzero closed degrees that do not bound nonzero degrees of enumerability, there are nonzero degrees of enumerability that do not bound nonzero closed degrees, and there are degrees that are nontrivially both degrees of enumerability and closed degrees. We also show that the compact degrees of enumerability exactly correspond to the cototal enumeration degrees.
Keywords
Cite
@article{arxiv.1803.09485,
title = {Comparing the degrees of enumerability and the closed Medvedev degrees},
author = {Paul Shafer and Andrea Sorbi},
journal= {arXiv preprint arXiv:1803.09485},
year = {2018}
}