A Co-analytic Cohen-Indestructible Maximal cofinitary Group
نویسندگان
چکیده
Assuming that every set is constructible, we find a Π1 maximal cofinitary group of permutations of N 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 Π1 maximal cofinitary group in L.
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ورودعنوان ژورنال:
- J. Symb. Log.
دوره 82 شماره
صفحات -
تاریخ انتشار 2017