English

A Note on Clockability for Ordinal Turing Machines

Logic 2026-05-19 v2

Abstract

We study clockability for Ordinal Turing Machines (OTMs). In particular, we show that, in contrast to the situation for ITTMs, admissible ordinals can be OTM-clockable, that Σ2\Sigma_{2}-admissible ordinals are never OTM-clockable and that gaps in the OTM-clockable ordinals are always started by admissible limits of admissible ordinals.

Cite

@article{arxiv.1906.10087,
  title  = {A Note on Clockability for Ordinal Turing Machines},
  author = {Merlin Carl},
  journal= {arXiv preprint arXiv:1906.10087},
  year   = {2026}
}
R2 v1 2026-06-23T10:02:11.727Z