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Preserving Preservation

Jakob Kellner·Saharon Shelah
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Abstract

We present preservation theorems for countable support iteration of nep forcing notions satisfying ``old reals are not Lebesgue null'' and ``old reals are not meager''. (Nep is a generalization of Suslin proper.) We also give some results for general Suslin ccc ideals.

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Jakob Kellner, Saharon Shelah. 2004-05-05. Preserving Preservation. https://doi.org/10.2178/jsl%2F1122038920

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