A note on derivatives, expansions and $\Pi^1_1$-ranks
Logic
2021-07-22 v1 Dynamical Systems
Abstract
-ranks are a natural tool for studying coanalytic sets in descriptive set theory. In the book "Classical descriptive set theory", Kechris provided a technique to build -ranks using derivatives. In this note we will prove a variant of this result that is applicable to the -rank. Some dynamical ranks, like the entropy rank can be stated in terms of the -rank.
Cite
@article{arxiv.2107.09866,
title = {A note on derivatives, expansions and $\Pi^1_1$-ranks},
author = {Udayan B. Darji and Felipe García-Ramos},
journal= {arXiv preprint arXiv:2107.09866},
year = {2021}
}
Comments
arXiv admin note: text overlap with arXiv:2107.09263