4 papers
A generic construction of free algebras in varieties of Hilbert algebras and Brouwerian semilattices
Tomasz Kowalski, Katarzyna SÅomczyÅska
We give a generic construction of the n-generated free Hilbert algebras and Brouwerian semilattices by a uniform method applicable to any variety of Hilbert algebras or Brouwerian…
Decidable varieties of p-algebras
Tomasz Kowalski, Katarzyna SÅomczyÅska
We show that for quasivarieties of p-algebras the properties of (i) having decidable first-order theory and (ii) having decidable first-order theory of the finite members, coincide…
Quasivarieties of p-algebras: some new results
Tomasz Kowalski, Katarzyna SÅomczyÅska
We investigate quasivarieties of (distributive) p-algebras. We sharpen some previous results, give a better picture of the subquasivariety lattice, and prove that quasivarieties ge…
Free p-algebras revisited: an algebraic investigation of implication-free intuitionism
Tomasz Kowalski, Katarzyna SÅomczyÅska
We give a new construction of free distributive p-algebras. Our construction relies on a detailed description of completely meet-irreducible congruences, so it is purely universal…