Boolean matrices, subalgebras and automorphisms of complete Boolean algebras
نویسندگان
چکیده
منابع مشابه
Regular Subalgebras of Complete Boolean Algebras
It is proved that the following conditions are equivalent: (a) there exists a complete, atomless, σ–centered Boolean algebra, which does not contain any regular, atomless, countable subalgebra, (b) there exists a nowhere dense ultrafilter on ω. Therefore the existence of such algebras is undecidable in ZFC. In ”forcing language” condition (a) says that there exists a non– trivial σ–centered for...
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 1977
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm-96-3-211-223