Problems on ${\hat{I}}^2\mathbb{N}$

Abstract

This is an update on, and expansion of, our paper Open problems on ${\hat{I}}^2\ddot{I}‰$ in the book Open Problems in Topology.

New version, much reworked. 2024-02-01: version after comments from the referee. 2024-08-24: added classification, keywords, some recent results. 2024-10-21: post-proofreading version, identical in content to the published version