English

Reducts of structures and maximal-closed permutation groups

Logic 2015-02-27 v2

Abstract

Answering a question of Junker and Ziegler, we construct a countable first order structure which is not omega-categorical, but does not have any proper non-trivial reducts, in either of two senses (model-theoretic, and group-theoretic). We also construct a strongly minimal set which is not omega-categorical but has no proper non-trivial reducts in the model-theoretic sense.

Keywords

Cite

@article{arxiv.1310.6393,
  title  = {Reducts of structures and maximal-closed permutation groups},
  author = {Manuel Bodirsky and Dugald Macpherson},
  journal= {arXiv preprint arXiv:1310.6393},
  year   = {2015}
}

Comments

3 figures

R2 v1 2026-06-22T01:52:52.818Z