English

Rosenthal compacta and NIP formulas

Logic 2015-08-10 v2

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.

Cite

@article{arxiv.1407.5761,
  title  = {Rosenthal compacta and NIP formulas},
  author = {Pierre Simon},
  journal= {arXiv preprint arXiv:1407.5761},
  year   = {2015}
}

Comments

14 pages, small corrections made

R2 v1 2026-06-22T05:09:36.056Z