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Coherent systems of finite support iterations
Vera Fischer, Sy D. Friedman, Diego A. Mejía +1
We introduce a forcing technique to construct three-dimensional arrays of generic extensions through FS (finite support) iterations of ccc posets, which we refer to as 3D-coherent…
Definable maximal cofinitary groups
Vera Fischer, Sy David Friedman, Asger Törnquist
Using countable support iteration of -proper posets, for some appropriate stationary set , we obtain a generic extension of the constructible universe, in which $\mathfrak{b}…
A co-analytic Cohen indestructible maximal cofinitary group
Vera Fischer, David Schrittesser, Asger Törnquist
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…