Preservation of a Souslin tree and side conditions

Giorgio Venturi

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arXiv · 1407.4050

Preservation of a Souslin tree and side conditions

Giorgio Venturi

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Abstract

We show how to force, with finite conditions, the forcing axiom PFA(T), a relativization of PFA to proper forcing notions preserving a given Souslin tree T. The proof uses a Neeman style iteration with generalized side conditions consisting of models of two types, and a preservation theorem for such iterations. The consistency of this axiom was previously known by the standard countable support iteration, using a preservation theorem due to Miyamoto.

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BibTeX RIS

Giorgio Venturi. 2014-07-15. Preservation of a Souslin tree and side conditions. https://arxiv.org/abs/1407.4050

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