A Note on Indestructibility and Strong Compactness
نویسنده
چکیده
If κ < λ are such that κ is both supercompact and indestructible under κ-directed closed forcing which is also (κ+,∞)-distributive and λ is 2λ supercompact, then by [3, Theorem 5], {δ < κ | δ is δ+ strongly compact yet δ isn’t δ+ supercompact} must be unbounded in κ. We show that the large cardinal hypothesis on λ is necessary by constructing a model containing a supercompact cardinal κ in which no cardinal δ > κ is 2δ = δ+ supercompact, κ’s supercompactness is indestructible under κ-directed closed forcing which is also (κ+,∞)-distributive, and for every measurable cardinal δ, δ is δ+ strongly compact iff δ is δ+ supercompact.
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