Dynamics of inspiraling dark energy

Journal Article · 06 April 2024 · European Physical Journal. C, Particles and Fields (Online)

DOI: https://doi.org/10.1140/epjc/s10052-024-12721-w · OSTI ID:2335433

Anguelova, Lilia; Dumancic, John; Gass, Richard; Wijewardhana, L. C. R.

Abstract We investigate the dynamics of a multifield dark energy model, which arises from certain rapid-turning and inspiraling trajectories in field space. We find the speed of sound $$$$c_s$$$$ $c_s$ of the dark energy perturbations around the background and show that $$$$c_s$$$$ $c_s$ is monotonically decreasing with time. Furthermore, it has a positive-definite lower bound that implies a certain clustering scale. We also extend the previously known background solution for dark energy to an exact solution that includes matter. This allows us to address the implications of our model for two cosmological tensions. More precisely, we argue that the $$$$\sigma _8$$$$ ${\sigma }_8$ tension can be alleviated generically, while reducing the Hubble tension requires certain constraints on the parameter space of the model. Notably, a necessary condition for alleviating the Hubble tension is that the transition from matter domination to the dark energy epoch begins earlier than in $$$$\Lambda $$$$ $\Lambda$ CDM.

• Sponsoring Organization: USDOE
• OSTI ID: 2335433
• Journal Information: European Physical Journal. C, Particles and Fields (Online), Journal Name: European Physical Journal. C, Particles and Fields (Online) Journal Issue: 4 Vol. 84; ISSN 1434-6052
• Publisher: Springer Science + Business MediaCopyright Statement
• Country of Publication: Germany
• Language: English