Non-linear dynamics and primordial black hole formation during kination
Abstract
Abstract We investigate the effects of large scalar inhomogeneities during the kination epoch, a period in which the universe's dynamics are dominated by the kinetic energy of a scalar field, by fully evolving the Einstein equations using numerical relativity. By tracking the non-linear growth of scalar perturbations with both sub-horizon and super-horizon initial wavelengths, we are able to compare their evolution to perturbative results. Our key findings show that in the deep sub-horizon limit, the perturbative behaviour remains valid, whereas in the super-horizon regime, non-linear dynamics exhibit a much richer phenomenology. Finally, we discuss the possibility of primordial black hole formation from the collapse of such perturbations and assess whether this process could serve as a viable mechanism to reheat the universe in the post-inflationary era.
Fields of Study & Subjects
Cosmology and Gravitation Theories
Galaxies: Formation
Evolution
Phenomena
Astrophysical Phenomena and Observations
Publication details
- Journal / source
- Journal of Cosmology and Astroparticle Physics
- Publisher
- IOP Publishing
- Volume
- 2026
- Issue
- 07
- Pages
- 048–048
- Publication date
- 1 July 2026
- Language
- EN