English

Lowering tensor-to-scalar ratio by pre-inflationary dynamics

Cosmology and Nongalactic Astrophysics 2020-09-30 v3 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology

Abstract

Pre-inflationary dynamics is known to have left observable imprints via the varied dynamics of the inflaton and the graviton fields during those epochs. It is highlighted here that other particle degrees of freedom, too, are capable of leaving their imprints on primordial observables if they transfer their entropies upon annihilation after becoming non-relativistic during a pre-inflationary epoch. Such annihilations of other particles would result in lowering of the tensor-to-scalar ratio at the pivot scale (and at length scales larger to that) which would help bring those potentials back in accordance with current observations which are otherwise disfavoured for yielding large tensor-to-scalar ratios at present.

Keywords

Cite

@article{arxiv.2005.07527,
  title  = {Lowering tensor-to-scalar ratio by pre-inflationary dynamics},
  author = {Suratna Das},
  journal= {arXiv preprint arXiv:2005.07527},
  year   = {2020}
}

Comments

5 pages, no figure, v2: typos corrected, references added, v3: Title changed as per the referee's comment, discussion extended, main results unchanged. Accepted for publication in PRD Rapid Communications

R2 v1 2026-06-23T15:34:21.541Z