Rosenthal compacta and NIP formulas

Pierre Simon

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arXiv · 1407.5761

Rosenthal compacta and NIP formulas

Pierre Simon

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Abstract

We apply the work of Bourgain, Fremlin and Talagrand on compact subsets of the first Baire class to show new results about phi-types for phi NIP. In particular, we show that if M is a countable model, then an M-invariant phi-type is Borel definable. Also the space of M-invariant phi-types is a Rosenthal compactum, which implies a number of topological tameness properties.

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BibTeX RIS

Pierre Simon. 2015-08-07. Rosenthal compacta and NIP formulas. https://arxiv.org/abs/1407.5761

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