The complexity of quasivariety lattices.~II

M. V. Schwidefsky

Sibirskie èlektronnye matematičeskie izvestiâ, Tome 20 (2023) no. 1, pp. 501-513.

Résumé

We prove that if a quasivariety $\mathbf{K}$ contains a finite $\mathrm{B}^\ast$-class relative to some subquasivariety and some variety possessing some additional property, then $\mathbf{K}$ contains continuum many $Q$-universal non-profinite subquasivarieties having an independent quasi-equational basis as well as continuum many $Q$-universal non-profinite subquasivarieties having no such basis.

Détail

Keywords: quasi-equational basis, quasivariety, profinite structure, profinite quasivariety.
Mots-clés : inverse limit

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