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arXiv · 1710.10650

Hypergraphs and proper forcing

Jindrich Zapletal
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Abstract

Given a Polish space X and a countable family of analytic hypergraphs on X, I consider the sigma-ideal generated by Borel sets which are anticliques in at least one hypergraph in the family. It turns out that many of the quotient posets are proper. I investigate the forcing properties of these posets, certain natural operations on them, and prove some related dichotomies. For this broad class of posets, most fusion arguments and iteration preservation arguments can be replaced with simple combinatorial considerations concerning the hypergraphs.

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Jindrich Zapletal. 2017-11-24. Hypergraphs and proper forcing. https://arxiv.org/abs/1710.10650

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