Fast Radio Bursts as probes of the late-time universe: a new insight on the Hubble tension

TL;DR

This study demonstrates that localized Fast Radio Bursts can effectively measure the Hubble constant in the late Universe, providing new insights into the persistent Hubble tension with improved precision over previous methods.

Contribution

It introduces a Bayesian analysis of 64 localized FRBs as late-time probes of the Hubble constant, highlighting their potential to clarify the Hubble tension.

Findings

FRBs can trace the Hubble constant in the late Universe.

Results have smaller error bars than previous studies.

Hubble constant measurements from FRBs do not overlap with early-Universe estimates.

Abstract

Fast Radio Bursts (FRBs) are bright radio transient events, a subset of which have been localized to their host galaxies. Their high dispersion measures offer valuable insights into the ionized plasma along their line of sight, enabling them to serve as probes of cosmological parameters. One of the major challenges in contemporary cosmology is the Hubble tension -- an unresolved discrepancy between two independent methods of determining the Universe's expansion rate, yielding differing values for the Hubble constant. In this study, we analyze a sample of 64 extragalactic, localized FRBs observed by various telescopes, employing Bayesian analysis with distinct likelihood functions. Our findings suggest that FRBs serve as tracers of the Hubble constant in the late-time Universe. Notably, our results exhibit smaller error bars compared to previous studies, and the derived Hubble constant with 1$\sigma$ error bars no longer overlap with those obtained from early-Universe measurements. These results underscore the continuing tension between early- and late-time measurements of the Hubble constant.