Lattices of Quasi-Equational Theories as Congruence Lattices of Semilattices with Operators: Part II
نویسندگان
چکیده
Part I proved that for every quasivariety K of structures (which may have both operations and relations) there is a semilattice S with operators such that the lattice of quasiequational theories of K (the dual of the lattice of sub-quasivarieties of K) is isomorphic to Con(S,+, 0,F). It is known that if S is a join semilattice with 0 (and no operators), then there is a quasivariety Q such that the lattice of theories of Q is isomorphic to Con(S,+, 0). We prove that if S is a semilattice having both 0 and 1 with a group G of operators acting on S, and each operator in G fixes both 0 and 1, then there is a quasivariety W such that the lattice of theories of W is isomorphic to Con(S,+, 0,G).
منابع مشابه
Lattices of Quasi-Equational Theories as Congruence Lattices of Semilattices with Operators: Part I
We show that for every quasivariety K of relational structures there is a semilattice S with operators such that the lattice of quasiequational theories of K (the dual of the lattice of sub-quasivarieties of K) is isomorphic to Con(S,+, 0, F). As a consequence, new restrictions on the natural quasi-interior operator on lattices of quasi-equational theories are found. 1. Motivation and terminolo...
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ورودعنوان ژورنال:
- IJAC
دوره 22 شماره
صفحات -
تاریخ انتشار 2012