Boolean semilattices
A Boolean semilattice is a structure A = (A,∨,0, ∧,1,¬,·) such that
A is in the variety generated by complex algebras of semilattices.
Let S = (S,·) be a semilattice. The
complex algebra of S is Cm(S) = (P(S),∪,Ø,
∩,S,−,·), where \langle P(S),\cup,\emptyset,
\cap,S,-\rangle is the Boolean algebra of subsets of S, and
Remark :
The complex algebra of any groupoid is a Boolean algebra with one binary operator.
<h3>Morphismsh3>
Let
<h3>Some resultsh3>
<h3>Examplesh3>
<h3>Propertiesh3>
<table border = 2>
Classtype
variety
[Finitely axiomatizable]?
open
Equational theory
Quasiequational theory
First-order theory
Locally finite
no
Residual size
unbounded
Congruence distributive
yes
Congruence modular
yes
Congruence n-permutable
yes, n=2
Congruence regular
yes
Congruence uniform
Congruence extension property
yes
Definable principal congruences
Equationally definable principal congruences
Amalgamation property
Strong amalgamation property
<h3>Finite membersh3>
[Size 1]? : 1Epimorphisms are surjective
[Size 2]? : 1
[Size 3]? : 0
[Size 4]? : 5
[Size 5]? : 0
[Size 6]? : 0
[Size 7]? : 0
[Size 8]? : ge 96$ out of 104
[Some members of BSlat]?