New constraints on Coupled Dark Energy from Planck

TL;DR

This paper uses Planck satellite data to place new constraints on coupled dark energy models, showing compatibility with observations and potential to resolve the Hubble tension, especially when combined with other datasets.

Contribution

It provides the first comprehensive constraints on coupled dark energy from Planck data, including combined analyses with HST and BAO measurements, and suggests evidence for non-zero coupling.

Findings

Coupled dark energy models are compatible with Planck data.

The Hubble tension can be alleviated with coupled dark energy.

Combined datasets indicate significant evidence for non-zero coupling.

Abstract

We present new constraints on coupled dark energy from the recent measurements of the Cosmic Microwave Background Anisotropies from the Planck satellite mission. We found that a coupled dark energy model is fully compatible with the Planck measurements, deriving a weak bound on the dark matter-dark energy coupling parameter \xi=-0.49^{+0.19}_{-0.31} at 68% c.l.. Moreover if Planck data are fitted to a coupled dark energy scenario, the constraint on the Hubble constant is relaxed to H_0=72.1^{+3.2}_{-2.3} km/s/Mpc, solving the tension with the Hubble Space Telescope value. We show that a combined Planck+HST analysis provides significant evidence for coupled dark energy finding a non-zero value for the coupling parameter \xi, with -0.90< \xi <-0.22 at 95% c.l.. We also consider the combined constraints from the Planck data plus the BAO measurements of the 6dF Galaxy Survey, the Sloan Digital Sky Survey and the Baron Oscillation Spectroscopic Survey.