| <Reference List> | |
| Type: | Preprint |
| National /International: | International |
| Title: | A note on varieties of ordered algebras |
| Publication Date: | 2026-02-26 |
| Authors: |
- Maria Manuel Clementino
- Diana Rodelo |
| Abstract: | The aim of this work is to study the notions of lax protomodular and Ord-Mal'tsev category at the level of (coherent) varieties of (pre)ordered algebras and to further compare them, as has been done in the non-ordered context. We characterise varieties of ordered algebras which are (co)lax protomodular and those which are Ord-Mal'tsev, in terms of operations of arities given by ordered sets and inequalities involving them. We exhibit examples of (co)lax protomodular non-degenerate Ord-categories, which were unknown. We prove that, for varieties of ordered algebras which are Ord-Mal'tsev categories, the order of their algebras is degenerate (i.e. is symmetric). As a consequence, the implication "protomodular \( \Rightarrow \) Mal'tsev" cannot be carried out to our context. The case of non-coherent ordered varieties which are Ord-Mal'tsev categories is also addressed, where we show the existence of algebras with non-degenerate order. |
| Institution: | DMUC 26-06 |
| Online version: | http://www.mat.uc.pt...prints/eng_2026.html |
| Download: | Not available |
