Abstract
It is a characteristic of grand unified theories with an axion of the type suggested by Dine, Fischler and Srednicki that they predict a very small neutron electric dipole moment because the QCD θ vacuum parameter is suppressed. The minimal SU(5) axion model of Wise, Georgi and Glashow yields a cosmological baryon-to-photon ratio in the same order as that in the minimal SU(5) model with one 5 of Higgs, which is much smaller than required by astrophysics. More complicated grand unified axion models can avoid this problem.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 298-302 |
| Number of pages | 5 |
| Journal | Physics Letters B |
| Volume | 106 |
| Issue number | 4 |
| DOIs | |
| State | Published - Nov 12 1981 |
| Externally published | Yes |