English

The reducts of equality up to primitive positive interdefinability

Logic 2010-01-16 v3 Rings and Algebras

Abstract

We initiate the study of reducts of relational structures up to primitive positive interdefinability: After providing the tools for such a study, we apply these tools in order to obtain a classification of the reducts of the logic of equality. It turns out that there exists a continuum of such reducts. Equivalently, expressed in the language of universal algebra, we classify those locally closed clones over a countable domain which contain all permutations of the domain.

Keywords

Cite

@article{arxiv.0810.2270,
  title  = {The reducts of equality up to primitive positive interdefinability},
  author = {Manuel Bodirsky and Hubie Chen and Michael Pinsker},
  journal= {arXiv preprint arXiv:0810.2270},
  year   = {2010}
}

Comments

41 pages; version 3 has been been checked also by non-authors