1991/09/23 by Tom Banks, Michael Dine, Nathan Seiberg · 8 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Particle physics theoretical and experimental studies #hep-th
paper · pdf · doi:10.1016/0370-2693(91)90561-4
published as Phys.Lett.B273:105-110,1991 · 12 pages
arxiv created 1991/09/23 · openalex publication_date 1991/12/01 · arxiv updated 2009/11/30 · openalex created_date 2020/11/23 · openalex updated_date 2026/07/29
We exhibit a novel solution of the strong CP problem, which does not involve any massless particles. The low energy effective Lagrangian of our model involves a discrete spacetime independent axion field which can be thought of as a parameter labeling a dense set of θ vacua. In the full theory this parameter is seen to be dynamical, and the model seeks the state of lowest energy, which has θeff = 0. The processes which mediate transitions between θ vacua involve heavy degrees of freedom and are very slow. Consequently, we do not know whether our model can solve the strong CP problem in a universe which has been cool for only a finite time. We present several speculations about the cosmological evolution of our model.