English

Right-cancellable protomodular algebras

Category Theory 2021-03-02 v1 General Topology Group Theory

Abstract

A new protomodular analog of the classical criterion for the existence of a group term in the algebraic theory of a variety of universal algebras is given. To this end, the notion of a right-cancellable protomodular algebra is introduced. It is proved that the algebraic theory of a variety of universal algebras contains a group term if and only if it contains protomodular terms with respect to which all algebras from the variety are right-cancellable. This, in particular, gives a partial answer to the extended version of an open problem from loop theory whether any Hausdorff topological (semi-)loop is completely regular. Moreover, the right-cancellable algebras from the simplest protomodular varieties are characterized as sets with principal group actions as well as groups with simple additional structures.

Keywords

Cite

@article{arxiv.2103.00278,
  title  = {Right-cancellable protomodular algebras},
  author = {Dali Zangurashvili},
  journal= {arXiv preprint arXiv:2103.00278},
  year   = {2021}
}
R2 v1 2026-06-23T23:34:18.257Z