On the C.E. degrees realizable in II⁰₁ classes

• Main Authors: Csima, Barbara F., Downey, Rod, Ng, Keng Meng
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2023
• Subjects: Science::Mathematics; Effectively Closed Sets; Computably Enumerable Degrees
• Online Access: https://hdl.handle.net/10356/171806
• Institution: Nanyang Technological University

We study for each computably bounded Π01 class P the set of degrees of c.e. paths in P. We show, amongst other results, that for every c.e. degree a there is a perfect Π01 class where all c.e. members have degree a. We also show that every Σ03 set of c.e. indices is realized in some perfect Π01 clas...