Steffen tells us about how the dispersion measure of fast radio bursts (FRBs) can be used to measure the distance to FRBs. Therefore, if we can find the host galaxies of FRBs and measure their redshifts we can measure the expansion rate (Hubble parameter) with FRBs.

And, he and his collaborators have done just that. At the moment the uncertainty is relatively large, but they still get a result within 10% of the more precise measurements (and consistent with both CMB and supernovae), indicating that they’re doing the right thing.

In the near future (less than five years) we’ll have (hopefully) more than 500 FRBs and a ~% level accuracy measurement of H0. These are exciting times for FRBs!

Paper: https://arxiv.org/abs/2104.04538
Steffen: https://www.su.se/english/profiles/stha5722-1.400226
Shaun’s tweet thread about the talk: https://twitter.com/just_shaun/status/1385147665244037123