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arXiv · 1409.4596

Why Y-c.c

David Chodounský·Jindřich Zapletal
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Abstract

We outline a portfolio of novel iterable properties of c.c.c. and proper forcing notions and study its most important instantiations, Y-c.c. and Y-properness. These properties have interesting consequences for partition-type forcings and anticliques in open graphs. Using Neeman's side condition method it is possible to obtain PFA variations and prove consistency results for them.

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BibTeXRIS

David Chodounský, Jindřich Zapletal. 2014-09-16. Why Y-c.c. https://doi.org/10.1016/j.apal.2015.07.001

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