Cosmological perturbations in generalised dark Lagrangians

Edholm, James; Pearson, Jonathan

Abstract

We describe a new method to parameterise dark energy theories including massive gravity, elastic dark energy and tensor-metric theories. We first examine the existing framework which describes any second order Lagrangian which depends on the variation of the metric and find new constraints on the parameters. We extend the method to Lorentz violating theories which depend on the variation of the time and spatial parts of the metric separately. We show how this can describe massive gravity and elastic dark energy, while ruling out the whole class of theories where the Lagrangian depends only on the variation of the time part of the metric. We further generalise our method to tensor-metric theories, both with and without splitting the metric into time and spatial parts. Our method extends existing physics by providing a mechanism to easily evaluate large classes of dark energy theories.

Citation

Edholm, J., & Pearson, J. (2018). Cosmological perturbations in generalised dark Lagrangians. Journal of High Energy Physics, 2018(11), Article 180. https://doi.org/10.1007/jhep11%282018%29180

• Journal Article Type: Article
• Acceptance Date: Nov 22, 2018
• Online Publication Date: Nov 28, 2018
• Publication Date: Nov 28, 2018
• Deposit Date: Jan 4, 2019
• Publicly Available Date: Jan 4, 2019
• Journal: Journal of High Energy Physics
• Print ISSN: 1126-6708
• Electronic ISSN: 1029-8479
• Publisher: Scuola Internazionale Superiore di Studi Avanzati (SISSA)
• Peer Reviewed: Peer Reviewed
• Volume: 2018
• Issue: 11
• Article Number: 180
• DOI: https://doi.org/10.1007/jhep11%282018%29180
• Public URL: https://durham-repository.worktribe.com/output/1310719