We investigate the arrival time and the Faraday rotation of extragalactic electromagnetic signals from fast radio bursts (FRBs) propagating through chiral cosmic media within the framework of Maxwell-Carroll-Field-Jackiw (MCFJ) electrodynamics. By treating the interstellar medium as a cold, ionized chiral plasma, we derive the time delay between two traveling signals, expressing it in terms of modified dispersion measures (DMs) containing chiral contributions. The Faraday rotation angle is then written in terms of modified rotation measures (RMs). By combining the DMs and redshift data from a set of FRBs, we obtain constraints on the chiral parameter magnitude at the order of 10−26--10−24 GeV. Using the Faraday rotation formulae and RM measurements, upper bounds as stringent as 10−43 GeV on the MCFJ parameters are also obtained.
@article{arxiv.2602.22996,
title = {Tight bounds on the Maxwell-Carroll-Field-Jackiw parameters using Fast Radio Bursts},
author = {Filipe S. Ribeiro and Pedro D. S. Silva and Rodolfo Casana and Manoel M. Ferreira},
journal= {arXiv preprint arXiv:2602.22996},
year = {2026}
}