The no-$\beta$ McMullen game and the perfect set property
Abstract
Given a target set and a real number , McMullen introduced the notion of being an absolutely -winning set. This involves a two player game which we call the -McMullen game. We consider the version of this game in which the parameter is removed, which we call the no- McMullen game. More generally, we consider the game with respect to arbitrary norms on , and even more generally with respect to general convex sets. We show that for strictly convex sets in , polytopes in , and general convex sets in , that player wins the no- McMullen game iff contains a perfect set and player wins iff is countable. So, the no- McMullen game is equivalent to the perfect set game for in these cases. The proofs of these results use a connection between the geometry of the game and techniques from logic. Because of the geometry of this game, this result has strong implications for the geometry of uncountable sets in . We also present an example of a compact, convex set in to which our methods do not apply, and also an example due to D.\ Simmons of a closed, convex set in which illustrate the obstacles in extending the results further.
Keywords
Cite
@article{arxiv.2110.03033,
title = {The no-$\beta$ McMullen game and the perfect set property},
author = {Logan Crone and Lior Fishman and Stephen Jackson},
journal= {arXiv preprint arXiv:2110.03033},
year = {2021}
}