Future Cosmological Constraints From Fast Radio Bursts

Abstract

We consider the possible observation of Fast Radio Bursts (FRBs) with planned future radio telescopes, and investigate how well the dispersions and redshifts of these signals might constrain cosmological parameters. We construct mock catalogues of FRB dispersion measure (DM) data and employ Markov Chain Monte Carlo (MCMC) analysis, with which we forecast and compare with existing constraints in the flat ΛCDM model, as well as some popular extensions that include dark energy equation of state and curvature parameters. We find that the scatter in DM observations caused by inhomogeneities in the intergalactic medium (IGM) poses a big challenge to the utility of FRBs as a cosmic probe. Only in the most optimistic case, with a high number of events and low IGM variance, do FRBs aid in improving current constraints. In particular, when FRBs are combined with CMB+BAO+SNe+H 0 data, we find the biggest improvement comes in the Ω b h 2 constraint. Also, we find that the dark energy equation of state is poorly constrained, while the constraint on the curvature parameter Ω k , shows some improvement when combined with current constraints. When FRBs are combined with future BAO data from 21cm Intensity Mapping (IM), we find little improvement over the constraints from BAOs alone. However, the inclusion of FRBs introduces an additional parameter constraint, Ω b h 2 , which turns out to be comparable to existing constraints. This suggest that FRBs provide valuable information about the cosmological baryon density in the intermediate redshift Universe, independent of high redshift CMB data.

Limits on the Weak Equivalence Principle and Photon Mass with FRB 121102 Subpulses

“…The first repeating burst FRB 121102, was localized in a star-forming dwarf galaxy at z = 0.193, which has confirmed the cosmological origin of FRBs Scholz et al 2016;Chatterjee et al 2017;Marcote et al 2017;Tendulkar et al 2017). Although the progenitors and radiation mechanism are still debated, FRBs have been proposed to be promising tools for cosmological and astrophysical studies, such as locating the "missing" baryons (Mcquinn 2014), constraining the cosmological parameters (Gao et al 2014;Zhou et al 2014;Yang & Zhang 2016a;Walters et al 2018), directly measure Ω b of the universe (Deng & Zhang 2014;Keane et al 2016) and probe the reionization history of the universe (Deng & Zhang 2014;Zheng et al 2014;Caleb et al 2019;Li et al 2019), probing compact dark matter or precisely measuring the Hubble constant and the cosmic curvature through gravitationally lensed FRBs (Muñoz et al 2016;Li et al 2018), measuring cosmic proper distances (Yu & Wang 2017), testing the Einstein's weak equivalence principle (WEP, Wei et al 2015;Nusser 2016;Tingay & Kaplan 2016;Wu et al 2017;Yu et al 2018) and constraining the rest mass of the photon Bonetti et al 2016Bonetti et al , 2017Shao & Zhang 2017).…”

Use of fast radio burst dispersion measures as distance measures

“…In particular, they could provide a good map of the baryon distribution, magnetic fields and turbulence in the IGM, helium reionization, and might serve as a new tool for measuring cosmological distances to high redshifts z 1, e.g. [21][22][23][24][25][26]. A new cosmological distance measure would be exciting, and useful, if it could be made sufficiently robust and competitive in precision to existing cosmological distance probes such as Type Ia supernovae standard candles and baryon acoustic oscillations standard rulers.…”

Energy function, formation rate, and low-metallicity environment of fast radio bursts

“…The localization of the FRB 121102 (Chatterjee et al 2017;Marcote et al 2017;Tendulkar et al 2017) confirmed the cosmological origin of this source (at z = 0.19). If many redshifts of FRBs are measured by upcoming instruments, the combined redshift and DM can be used as cosmological purpose, including measuring the baryon number density (Deng & Zhang 2014;Keane et al 2016), measuring cosmic proper distance , constraining the cosmological parameters (Zhou et al 2014;Gao et al 2014;Walters et al 2018), measuring the Hubble Constant and cosmic curvature if some repeating FRBs are gravitationally lensed (Li et al 2018), probing compact dark matter through strong lensed FRBs (Muñoz et al 2016;) and testing ⋆ E-mail: fayinwang@nju.edu.cn Einstein's Weak Equivalence Principle (WEP) (Wei et al 2015;Yu et al 2018).…”