Non-parametric reconstruction of interaction in the cosmic dark sector

TL;DR

This paper employs a non-parametric, data-driven approach using Gaussian Processes to investigate potential interactions between dark matter and dark energy, finding no significant interaction at present and confirming energy flow from dark energy to dark matter.

Contribution

It introduces a non-parametric reconstruction method for dark sector interactions directly from observational data, avoiding predefined interaction models.

Findings

No significant interaction detected at present epoch

Energy flows from dark energy to dark matter

Results consistent with thermodynamic expectations

Abstract

The possibility of a non-gravitational interaction between the dark matter and the dark energy has been reconstructed using some recent datasets. The crucial aspect is that the interaction is not parametrized at the outset, but rather reconstructed directly from the data in a non-parametric way. The Cosmic Chronometer Hubble data, the Pantheon Supernova compilation of CANDELS and CLASH Multy-Cycle Treasury programs obtained by the HST, and the Baryon Acoustic Oscillation Hubble data have been considered in this work. The widely accepted Gaussian Process is used for the reconstruction. The results clearly indicate that a no interaction scenario is quite a possibility. Also, the interaction, if any, is not really significant at the present epoch. The direction of the flow of energy is clearly from the dark energy to the dark matter which is consistent with the thermodynamic requirement.