Coding in the automorphism group of a computably categorical structure
Logic
2020-01-29 v2
Abstract
Using new techniques for controlling the categoricity spectrum of a structure, we construct a structure with degree of categoricity but infinite spectral dimension, answering a question of Bazhenov, Kalimulin and Yamaleev. Using the same techniques, we construct a computably categorical structure of non-computable Scott rank, and a structure of computable dimension 2 such that there is no hyperarithmetic isomorphism between the two copies.
Keywords
Cite
@article{arxiv.1905.07850,
title = {Coding in the automorphism group of a computably categorical structure},
author = {Dan Turetsky},
journal= {arXiv preprint arXiv:1905.07850},
year = {2020}
}