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Commutative residuated lattices
Abbreviation: CRL
Definition
A \emph{commutative residuated lattice} is a residuated lattice L=⟨L,∨,∧,⋅,e,∖,/⟩ such that
⋅ is commutative: xy=yx
Remark:
Morphisms
Let L and M be commutative residuated lattices. A morphism from L to M is a function h:L→M that is a homomorphism:
h(x∨y)=h(x)∨h(y), h(x∧y)=h(x)∧h(y), h(x⋅y)=h(x)⋅h(y), h(x∖y)=h(x)∖h(y), h(x/y)=h(x)/h(y), and h(e)=e
Examples
Example 1:
Basic results
Properties
Classtype | Variety |
---|---|
Equational theory | Decidable |
Quasiequational theory | Undecidable |
First-order theory | Undecidable |
Locally finite | No |
Residual size | Unbounded |
Congruence distributive | Yes |
Congruence modular | Yes |
Congruence n-permutable | Yes, n=2 |
Congruence regular | No |
Congruence e-regular | Yes |
Congruence uniform | No |
Congruence extension property | Yes |
Definable principal congruences | No |
Equationally def. pr. cong. | No |
Amalgamation property | |
Strong amalgamation property | |
Epimorphisms are surjective |
Finite members
f(1)=1f(2)=1f(3)=3f(4)=16f(5)=100f(6)=794f(7)=7493f(8)=84961
Subclasses
Superclasses
Commutative multiplicative lattices
Commutative residuated join-semilattices