2021/05/31 by Meysam Motaharfar, Rudnei O. Ramos · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Classical mechanics #Cosmology and Gravitation Theories #Dissipation #Dissipative system #Galaxies: Formation, Evolution, Phenomena #Inflation (cosmology) #Inflaton #Physics #Quantum electrodynamics #Quantum mechanics #String (physics) #String theory #Theoretical physics #astro-ph.CO #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.104.043522
published as Phys. Rev. D 104, 043522 (2021) · 13 pages, 1 figure. Replaced with version matching the published one
openalex publication_date 2021/08/16 · arxiv created 2021/08/17 · arxiv updated 2021/08/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider warm inflation with a Dirac-Born-Infeld (DBI) kinetic term in which both the nonequilibrium dissipative particle production and the sound speed parameter slow the motion of the inflaton field. We find that a low sound speed parameter removes, or at least strongly suppresses, the growing function appearing in the scalar of curvature power spectrum of warm inflation, which appears due to the temperature dependence in the dissipation coefficient. As a consequence of that, a low sound speed helps to push warm inflation into the strong dissipation regime, which is an attractive regime from a model building and phenomenological perspective. In turn, the strong dissipation regime of warm inflation softens the microscopic theoretical constraints on cold DBI inflation. The present findings, along with the recent results from swampland criteria, give a strong hint that warm inflation may consistently be embedded into string theory.