We provide upper and lower bounds in consistency strength for the theories "ZF + ¬ACω + All successor cardinals except successors of uncountable limit cardinals are regular + Every uncountable limit cardinal is singular + The successor of every uncountable limit cardinal is singular of cofinality ω" and "ZF + ¬ACω + All successor cardinals except successors of uncountable limit cardinals are regular + Every uncountable limit cardinal is singular + The successor of every uncountable limit cardinal is singular of cofinality ω 1". In particular, our models for both of these theories satisfy "ZF + ¬ACω + κ is singular iff κ is either an uncountable limit cardinal or the successor of an uncountable limit cardinal".
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We construct a model containing a proper class of strongly compact cardinals in which no strongly compact cardinal ĸ is $ĸ^+$ supercompact and in which every strongly compact cardinal has its strong compactness resurrectible.
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We force and construct a model in which GCH and level by level equivalence between strong compactness and supercompactness hold, along with certain additional "L-like" combinatorial principles. In particular, this model satisfies the following properties: (1) ◊ δ holds for every successor and Mahlo cardinal δ. (2) There is a stationary subset S of the least supercompact cardinal κ 0 such that for every δ ∈ S, [...]δ holds and δ carries a gap 1 morass. (3) A weak version of [...]δ holds for every infinite cardinal δ. (4) There is a locally defined well-ordering of the universe W, i.e., for all κ ≥ ℵ 2 a regular cardinal, W↑H(κ+) is definable over the structure (H(κ+), ∈} by a parameter free formula. The model constructed amalgamates and synthesizes results due to the author, the author and Cummings, and Aspero and Sy Friedman. It has no restrictions on the structure of its class of supercompact cardinals and may be considered as part of Friedman's "outer model programme".
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