PreprintCC BY 4.0arXiv
A Note on Lowness for Π01-Immunity
Abstract
We show that the only degree which cannot co-enumerate a non-trivial Π01-immune real is ∅, resolving a conjecture of the author. The main ingredient is that if a real A has that all A-maximal sets are c.e., then A has c.e. degree, which can be proved via a coding mechanism and two classical results of Lachlan.
Related
BibTeX
@misc{webb2026note,
title = {{A Note on Lowness for $Π^0_1$-Immunity}},
author = {David J. Webb},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.13297},
eprint = {2609.13297},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.13297},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - A Note on Lowness for Π^0_1-Immunity
AU - David J. Webb
PY - 2026
DA - 2026/09/09
PB - arXiv
DO - 10.48550/arxiv.2609.13297
UR - https://arxiv.org/abs/2609.13297
AB - We show that the only degree which cannot co-enumerate a non-trivial Π^0_1-immune real is ∅, resolving a conjecture of the author. The main ingredient is that if a real A has that all A-maximal sets are c.e., then A has c.e. degree, which can be proved via a coding mechanism and two classical results of Lachlan.
ER -