arXiv 0810.56412008-10math.LO

Forcings constructed along morasses

Bernhard Irrgang

备注：: accepted for the Journal of Symbolic Logic, various minor changes were made to the previous version

英文摘要：

In a previous paper, we introduced a way of constructing a forcing along a simplified gap-1 morass such that the forcing satisfies a chain condition. Now, we generalize this to gap-2 morasses. As an application, we prove that GCH is consistent with the existence of a 0-dimensional Hausdorff topology on $ω_3$ which has spread $ω_1$.

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