Published online by Cambridge University Press: 29 March 2021
We determine the reflexivity index of some closed set lattices by constructing maps relative to irrational rotations. For example, various nests of closed balls and some topological spaces, such as even-dimensional spheres and a wedge of two circles, have reflexivity index 2. We also show that a connected double of spheres has reflexivity index at most 2.
This research was partly supported by the National Natural Science Foundation of China (Grant No. 11871021).