Well-tempered cosmology

Emond, William T.; Li, Chunhao; Saffin, Paul M.; Zhou, Shuang-Yong

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.

Citation

Emond, W. T., Li, C., Saffin, P. M., & Zhou, S.-Y. (2019). Well-tempered cosmology. Journal of Cosmology and Astroparticle Physics, 2019(05), Article 038. https://doi.org/10.1088/1475-7516/2019/05/038

• Journal Article Type: Article
• Acceptance Date: May 7, 2019
• Online Publication Date: May 22, 2019
• Publication Date: May 22, 2019
• Deposit Date: May 24, 2019
• Publicly Available Date: May 23, 2020
• Journal: Journal of Cosmology and Astroparticle Physics
• Electronic ISSN: 1475-7516
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 2019
• Issue: 05
• Article Number: 038
• DOI: https://doi.org/10.1088/1475-7516/2019/05/038
• Keywords: Astronomy and Astrophysics
• Public URL: https://nottingham-repository.worktribe.com/output/2088982
• Publisher URL: https://iopscience.iop.org/article/10.1088/1475-7516/2019/05/038
• Contract Date: May 24, 2019