We show that an axionlike field coupled to a new confining gauge group can generate the primordial density perturbation in the postinflation Universe. The axion decay constant and strong coupling scale are uniquely determined by observations of the density perturbation, which further suggest a temporal deconfinement of the gauge group after inflation. The resulting temperature-dependent axion potential, together with its periodic nature, gives rise to the red-tilted density perturbation, with a positive local-type non-Gaussianity of order unity.
Physical Review Letters
- Pub Date:
- July 2020
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- High Energy Physics - Phenomenology;
- High Energy Physics - Theory
- 7 pages, 1 figure, v2: published in PRL