Well-Tempered Cosmology
Abstract
We examine an approach to cosmology, known as Well-Tempering, that allows for a de Sitter phase whose expansion is independent of the cosmological constant. Starting from a generic scalar-tensor theory compatible with the recent gravitational wave observation, we impose the Well-Tempering conditions and derive a system that is capable of tuning away the cosmological constant within a sub-class of Horndeski theory, where the scalar has a canonical kinetic term and a general potential. This scenario improves upon the Fab-Four approach by allowing a standard fluid-cosmology before entering the de Sitter phase, and we present an explicit example of our general solution.
Cite
@article{arxiv.1812.05480,
title = {Well-Tempered Cosmology},
author = {William T. Emond and Chunhao Li and Paul M. Saffin and Shuang-Yong Zhou},
journal= {arXiv preprint arXiv:1812.05480},
year = {2019}
}
Comments
21 pages, 6 figures. Updated to include appendix, and match published version