English

A rank based on Shelah trees

Logic 2022-02-16 v5

Abstract

We define a global rank for partial types based in a generalization of Shelah trees. We prove an equivalence with the depth of a localized version of the constructions known as dividing sequence and dividing chain. This rank characterizes simple and supersimple types. Moreover, this rank does not change for non-forking extensions under certain hypothesys. We also prove this rank satisfies Lascar-style inequalities.

Keywords

Cite

@article{arxiv.1912.12279,
  title  = {A rank based on Shelah trees},
  author = {Santiago Cárdenas-Martín and Rafel Farré},
  journal= {arXiv preprint arXiv:1912.12279},
  year   = {2022}
}
R2 v1 2026-06-23T12:57:39.559Z