New Constraint of the Hubble Constant by Proper Motions of Radio Components Observed in AGN Twin-jets

TL;DR

This paper proposes a new method to constrain the Hubble constant using proper motions of radio components in AGN twin-jets, providing a lower limit consistent with existing measurements and addressing the tension in cosmological data.

Contribution

It introduces a geometrical approach based on AGN twin-jet proper motions to independently estimate a lower limit of the Hubble constant.

Findings

Lower limit of H0: 51.5 ± 2.3 km/s/Mpc from NGC 1052 data.

Method provides an independent constraint on H0 using radio jet observations.

Supports the ongoing effort to resolve Hubble constant discrepancies.

Abstract

As the advent of precision cosmology, the Hubble constant ($H_0$) inferred from the Lambda Cold Dark Matter fit to the Cosmic Microwave Background data is increasingly in tension with the measurements from the local distance ladder. To approach its real value, we need more independent methods to measure, or to make constraint of, the Hubble constant. In this paper, we apply a plain method, which is merely based on the Friedman-Lema\^itre-Robertson-Walker cosmology together with geometrical relations, to constrain the Hubble constant by proper motions of radio components observed in AGN twin-jets. Under the assumption that the ultimate ejection strengths in both sides of the twin-jet concerned are intrinsically the same, we obtain a lower limit of the $H_{\rm 0,min}=51.5\pm2.3\,\rm km\,s^{-1}\,Mpc^{-1}$ from the measured maximum proper motions of the radio components observed in the twin-jet of NGC 1052.