Status of early dark energy after DESI: the role of $\Omega_m$ and $r_s H_0$

Abstract

The EDE model is one of the promising solutions to the long-standing Hubble tension. This paper investigates the status of several EDE models in light of recent BAO observations from the Dark Energy Spectroscopic Instrument (DESI) and their implications for resolving the Hubble tension. The DESI Y1 BAO results deviate from the CMB and Type Ia supernova (SNeIa) observations in their constraints on the matter density $\Omega_m$ and the product of the sound horizon and the Hubble constant $r_s H_0$. Meanwhile, these EDE models happen to tend towards this deviation. Therefore, in this work, it is found that DESI Y1 BAO results strengthen the preference for EDE models and help to obtain a higher $H_0$. Even considering the Pantheon+ observations for SNeIa, which have an opposite tendency, DESI still dominates the preference for EDE. This was unforeseen in past SDSS BAO measurements and therefore emphasizes the role of BAO and SNeIa measurements in Hubble tension.