Generalized Quasiorders and the Galois Connection End-gQuord
Abstract
Equivalence relations or, more general, quasiorders (i.e., reflexive and transitive binary relations) have the property that an -ary operation preserves , i.e., is a polymorphism of , if and only if each translation (i.e., unary polynomial function obtained from by substituting constants) preserves , i.e., it is an endomorphism of . We introduce a wider class of relations -- called generalized quasiorders -- of arbitrary arities with the same property. With these generalized quasiorders we can characterize all algebras whose clone of term operations is determined by its translations by the above property, what generalizes affine complete algebras. The results are based on the characterization of so-called u-closed monoids (i.e., the unary parts of clones with the above property) as Galois closures of the Galois connection End-gQuord, i.e., as endomorphism monoids of generalized quasiorders. The minimal u-closed monoids are described explicitly.
Keywords
Cite
@article{arxiv.2307.01868,
title = {Generalized Quasiorders and the Galois Connection End-gQuord},
author = {Danica Jakubíková-Studenovská and Reinhard Pöschel and Sándor Radeleczki},
journal= {arXiv preprint arXiv:2307.01868},
year = {2023}
}