Some open questions in axion theory
arXiv:2203.08026
Abstract
This white paper collects some open questions in several different aspects of axion theories. The questions are related to quantization of axion couplings, axion-magnetic monopole systems, axions in quantum gravity theory, axion string/domain wall systems, and thermal friction from axion couplings. They demonstrate many opportunities for axion theory, which call for more studies.
12 pages, contribution to Snowmass 2021