Some basic thoughts on the cofiality of Chang structures with an application to forcing [article]

Dominik Adolf
2020 arXiv   pre-print
Consider (κ^+++,κ^++) (κ^+,κ) where κ is an uncountable regular cardinal. By a result of Shelah's we have cof(X ∩κ^++) = κ for almost all X ⊂κ^+++ witnessing this. Here we consider the question if there could be a similar result for X ∩κ^+. We use this discussion to give an interesting example of a pseudo Prikry forcing answering a question of Sinapova.
arXiv:2003.11215v1 fatcat:wj63t2atcfbwffkynxmuztggla