Download PDF - Retracts and Q-independence
ArticleOriginal scientific text
Title
Retracts and Q-independence
Authors 1
Affiliations
- Opole University of Technology, Waryńskiego 4, 45-047 Opole, Poland
Abstract
A non-empty set X of a carrier A of an algebra A is called Q-independent if the equality of two term functions f and g of the algebra A on any finite system of elements a₁,a₂,...,aₙ of X implies f(p(a₁),p(a₂),...,p(aₙ)) = g(p(a₁),p(a₂),...,p(aₙ)) for any mapping p ∈ Q. An algebra B is a retract of A if B is the image of a retraction (i.e. of an idempotent endomorphism of B). We investigate Q-independent subsets of algebras which have a retraction in their set of term functions.
Keywords
general algebra, term function, Q-independence, M, I, S, S₀, A₁, G-independence, t-independence, retraction, retract, Stone algebra, skeleton and set of dense element of Stone algebra, Glivenko congruence
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