Reflection principles for $\omega_2$ and the semi-stationary reflection principle
نویسندگان
چکیده
منابع مشابه
Semistationary and stationary reflection
We study the relationship between the semistationary reflection principle and stationary reflection principles. We show that for all regular cardinals λ ≥ ω2 the semistationary reflection principle in the space [λ] implies that every stationary subset of E ω := {α ∈ λ | cf(α) = ω} reflects. We also show that for all cardinals λ ≥ ω3 the semistationary reflection principle in [λ] does not imply ...
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Let HC ′ denote the set of sets of hereditary cardinality less than 2ω. We consider reflection principles for HC ′ in analogy with the Levy reflection principle for HC. Let B be a class of complete Boolean algebras. The principle Max(B) says: If R(x1, . . . , xn) is a property which is provably persistent in extensions by elements of B, then R(a1, . . . , an) holds whenever a1, . . . , an ∈ HC ...
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ژورنال
عنوان ژورنال: Journal of the Mathematical Society of Japan
سال: 2016
ISSN: 0025-5645
DOI: 10.2969/jmsj/06831081