Gustavo Silveira Axion Dark Matter, Proton Decay and Unification Pavel Fileviez Perez, Clara Murgui, Alexis D. Plascencia JHEP(2020) 2020: 91 Hide abstract | Show figures | Show BibTeX | Show discussion | View PDF | 1911.05738v2 We discuss the possibility to predict the QCD axion mass in the context of grand unified theories. We investigate the implementation of the DFSZ mechanism in the context of renormalizable SU(5) theories. In the simplest theory, the axion mass can be predicted with good precision in the range ma=(2−16) neV, and there is a strong correlation between the predictions for the axion mass and proton decay rates. In this context, we predict an upper bound for the proton decay channels with antineutrinos, τ(p→K+ν¯)≲4×1037 yr and τ(p→π+ν¯)≲2×1036 yr. This theory can be considered as the minimal realistic grand unified theory with the DFSZ mechanism and it can be fully tested by proton decay and axion experiments. Authors' comments: 17 pages, 4 figures. v2: minor comments and references added, matches version published in JHEP