Speaker
Arkady Vainshtein
(University of Minnesota)
Description
We revisit the issue of the vacuum angle $\theta$ dependence in the weakly coupled (Higgsed) Yang-Mills theories. Anselm and Johansen noted that the vacuum angle $\theta_{\rm EW}$ associated with the electroweak SU(2) of the Standard Model is unobservable although all fermions get masses through Higgsing and there is no axion. We generalize this idea to a broad class of Higgsed Yang-Mills theories. We also consider the issue in frameworks of Grand Unification where situation turns out to be different.
Author
Arkady Vainshtein
(University of Minnesota)