Avoiding the string swampland in single-field inflation: Excited initial states
Abstract
One class of single-field inflationary models compatible with the recently-conjectured Swampland criteria would be those in which a Hubble slow-roll parameter is not the same as . However, a roadblock for these models (with a convex potential) lie in the unacceptably high tensor-to-scalar ratio, , generically predicted by them. In this work, illustrating through an explicit example, we point out that having a non-Bunch-Davies component to the initial state of cosmological perturbations makes the value of compatible with observations. In this way, we lay down a new path even for standard models of slow-roll inflation to be consistent with the Swampland criteria by invoking deviations from the Bunch-Davies initial state.
Keywords
Cite
@article{arxiv.1809.01277,
title = {Avoiding the string swampland in single-field inflation: Excited initial states},
author = {Suddhasattwa Brahma and Md. Wali Hossain},
journal= {arXiv preprint arXiv:1809.01277},
year = {2019}
}
Comments
9 pages; comments welcome; v2: version accepted in JHEP