Understanding the suppression of structure formation from dark matter-dark energy momentum coupling

Chamings, Finlay Noble; Avgoustidis, Anastasios; Copeland, Edmund J; Green, Anne M.; Pourtsidou, Alkistis

Abstract

Models in which scalar field dark energy interacts with dark matter via a pure momentum coupling have previously been found to potentially ease the structure formation tension between early-and late-universe observations. In this article we explore the physical mechanism underlying this feature. We argue analytically that the perturbation growth equations imply the suppression of structure growth, illustrating our discussion with numerical calculations. Then we generalise the previously studied quadratic coupling between the dark energy and dark matter to a more general power law case, also allowing for the slope of the dark energy exponential potential to vary. We find that the structure growth suppression is a generic feature of power law couplings and it can, for a range of parameter values, be larger than previously found.

Citation

Chamings, F. N., Avgoustidis, A., Copeland, E. J., Green, A. M., & Pourtsidou, A. (2020). Understanding the suppression of structure formation from dark matter-dark energy momentum coupling. Physical Review D, 101(4), https://doi.org/10.1103/physrevd.101.043531

• Journal Article Type: Article
• Acceptance Date: Feb 7, 2020
• Online Publication Date: Feb 24, 2020
• Publication Date: Feb 24, 2020
• Deposit Date: Feb 12, 2020
• Publicly Available Date: Feb 24, 2020
• Journal: Physical Review D
• Print ISSN: 2470-0010
• Electronic ISSN: 2470-0029
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 101
• Issue: 4
• DOI: https://doi.org/10.1103/physrevd.101.043531
• Keywords: Physics and Astronomy (miscellaneous)
• Public URL: https://nottingham-repository.worktribe.com/output/3949761
• Publisher URL: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.101.043531