English

Topological dynamics and NIP fields

Logic 2020-10-29 v1

Abstract

We study definable topological dynamics of some algebraic group actions over an arbitrary NIP field KK. We show that the Ellis group of the universal definable flow of SL2(K)\mathrm{SL}_2(K) is non-trivial if the multiplicative group of KK is not type-definably connected, providing a way to find multiple counterexamples to the Ellis group conjecture, particularly in the case of dp-minimal fields. We also study some structure theory of algebraic groups over KK with definable f-generics.

Keywords

Cite

@article{arxiv.2010.14586,
  title  = {Topological dynamics and NIP fields},
  author = {Grzegorz Jagiella},
  journal= {arXiv preprint arXiv:2010.14586},
  year   = {2020}
}
R2 v1 2026-06-23T19:41:57.218Z