Abstract:
This paper its content associated with the study of model-theoretic properties of Jonsson theories and their semantic models. In particular, considering Jonsson sets concerning of their definable circuit described frag-ments and their relationship to their centers. In the article considered Jonsson analogue of the question A.D.Taymanov of the existence of a sequence of Boolean algebras isomorphic to the corresponding algebras Lindenbaum-Tarski considered a complete theory. When Jonsson theory instead of Boolean algebras are con-sidered lattices of existential formulas. Is studied the connection of companions of fragment of Jonsson set with respect to the conservation of properties of stability.