Morasses and finite support iterations

Bernhard Irrgang

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arXiv · 0810.5217

Morasses and finite support iterations

Bernhard Irrgang

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Abstract

We introduce a method of constructing a forcing along a simplified $(κ,1)$-morass such that the forcing satisfies the $κ$-chain condition. Alternatively, this may be seen as a method to thin out a larger forcing to get a chain condition. As an application, we construct a ccc forcing that adds an $ω_2$-Suslin tree. Related methods are Shelah's historic forcing and Todorcevic's $ρ$-functions.

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BibTeX RIS

Bernhard Irrgang. 2008-10-29. Morasses and finite support iterations. https://arxiv.org/abs/0810.5217

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