A co-analytic Cohen indestructible maximal cofinitary group
arXiv:1603.02024 · doi:10.1017/jsl.2017.5
Abstract
Assuming that every set is constructible, we find a maximal cofinitary group of permutations of which is indestructible by Cohen forcing. Thus we show that the existence of such groups is consistent with arbitrarily large continuum. Our method also gives a new proof, inspired by the forcing method, of Kastermans' result that there exists a maximal cofinitary group in .
Minor corrections