Dark energy after pre-recombination early dark energy in light of DESI DR2 and the latest ACT and SPT data

TL;DR

This study investigates how pre-recombination early dark energy (EDE) affects the preference for evolving dark energy models using recent datasets, showing that EDE can reconcile evolving DE with current observations and Hubble tension resolutions.

Contribution

It clarifies and confirms that EDE allows for a quintessence-like dark energy component to be consistent with recent datasets, impacting the understanding of dark energy's nature.

Findings

EDE makes evolving dark energy models compatible with datasets.

A quintessence-like component can be 1σ consistent with combined datasets.

EDE significantly improves fit compared to models without EDE.

Abstract

It has been noted that with the pre-recombination early dark energy (EDE) resolution of Hubble tension, the preference of recent datasets for the evolving dark energy (DE) can be suppressed significantly. In this work, we clarify and reconfirm this result with DESI DR2 and the latest ACT DR6 and SPT-3G D1, the tightest small-scale CMB constraints up to date. In the $w_0w_a$CDM model with EDE, a quintessence-like component ($w_0+w_a\geq-1$) can be 1$\sigma$ consistent with Planck+ACT+SPT+DESI+Pantheon+SH0ES datasets, and $\Delta\chi^2\lesssim -14$ compared with $w_0w_a$CDM model without EDE. This reveals the possibility that when the potential resolutions of Hubble tension are considered, current accelerated expansion can attribute to a canonical evolving scalar field or cosmological constant, and again highlights the importance of re-examining the nature of DE within the broader context of cosmological tensions.