[Cosmology seminar] Recent advances in 21cm cosmology

In principle, the redshifted 21cm line from neutral hydrogen allows us to map the 3D structure of the Universe from the present day all the way back to the Dark Ages. The brightness of Galactic foreground emission, coupled with the difficulty of accurately characterising the spectral response of radio instruments, makes this rather tricky however. I will review some recent results from 21cm experiments at a range of redshifts, including recent detections of the cosmological 21cm signal with the MeerKAT array. I will then discuss some methodological advances involving ultra high dimensional Bayesian models (~millions of parameters), and how these can help us make precision 21cm cosmology a reality.