Remarks on generic stability in independent theories [article]

Gabriel Conant, Kyle Gannon
2019 arXiv   pre-print
In NIP theories, generically stable Keisler measures can be characterized in several ways. We analyze these various forms of "generic stability" in arbitrary theories. Among other things, we show that the standard definition of generic stability for types coincides with the notion of a frequency interpretation measure. We also give combinatorial examples of types in NSOP theories that are finitely approximated but not generically stable, as well as ϕ-types in simple theories that are definable
more » ... nd finitely satisfiable in a small model, but not finitely approximated. Our proofs demonstrate interesting connections to classical results from Ramsey theory for finite graphs and hypergraphs.
arXiv:1905.11915v3 fatcat:ygeii5lisrcotkl4siqcs6wyl4