Summary
IfT is a complete theory of Boolean algebra, then we writeA ⊲T B to denote that for every cardinal κ and every κ-regular filter over a setI such that the Boolean algebra 2 F I of all subsets ofI reduced byF is a model ofT, the reduced powerA F I isK +-saturated wheneverB F I isK +-saturated. The relation ⊲T generalizes the relation ◃ introduced by Keisler. As in the case of Keisler's ◃ it happens that ⊲T’s are relations between complete theories, i.e. ifA≡B thenA ⊲T B andB ⊲T A. In this paper some examples of theories which are maximal (minimal) with respect to ⊲T’s are provided and the relations ⊲T are compared with each other.
Similar content being viewed by others
References
M. Benda,On saturated reduced products, Pacific Journal of Mathematics39 (1971), 447–571.
M. Benda,On reduced products and filters, Annals of mathematical logic4 (1972), 1–29.
C. C. Chang andH. J. Keisler,Model theory, North-Holland., Amsterdam 1973.
Yu. L. Ershov,Decidability of the elementary theory of distributive lattices with relative complements and of the theory of filters, (in Russian), Algebra i Logika (Seminar) 3.3 (1964), 17–38.
H. J. Keisler,Ultraproducts which are not saturated, The Journal of Symbolic Logic32 (1967), 23–46.
H. J. Keisler,Formulas with linearly ordered quantifiers in: J. Barwise (Ed)The syntax and semantics of infinitary languages (Springer Lecuture Notes, Berlin 1969), 96–130.
A. I. Omarov,Saturated Boolean algebras, (in Russian), Siberian Mathematical Journal15 (1974), 1414–1415.
L. Pacholski,On products of first order theories, Bull. Acad. Polon. Sci., ser. sci. math. astr. et phys.17 (1969), 793–796.
S. Shelah,For what filters is every reduced product saturated!, Israel Journal of Mathematics12 (1972), 22–31.
S. Shelah,Saturation of ultrapowers and Keisler's order, AML4 (1972), 75–114.
A. Tarski,Arithmetical classes and types of Boolean algebras, Bulletin of the American Mathematical Society55 (1949), pp. 64 and 1192.
J. Waszkiewicz andB. Weglorz, On ω0-categoricity of powers, Bull. Acad. Polon. Sci., ser. sci. math., astr. et phys.17 (1969), 195–199.
J. Wierzejewski,On stability and products, Fundamenta Mathematicae,93 (1976), 81–95.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Pacholski, L., Tomasik, J. Reduced products which are not saturated. Algebra Universalis 14, 210–227 (1982). https://doi.org/10.1007/BF02483921
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02483921