The History of the Decline and Fall of Little h

For over four decades, the dimensionless Hubble constant (or little h) has been a constant presence in distances, times, masses, and luminosities for cosmologists and extragalactic astrophysicists, baffling the uninitiated to no end about the interpretation of these values. But one theorist dared to submit a paper to Publications of the Astronomical Society of Australia and say ’This far, and no farther!’ In this talk, we review Darren Croton's 2013 paper (arXiv:1308.4150), which helps newcomers survive (and hopefully outlive) the tyranny of little h. First, we review the history of measurements of the Hubble constant and the creation of little h. We then consider how simulated and observed quantities scale with little h, how to maintain your sanity in reviewing literature that uses - and sometimes misuses - little h, and how you should (or shouldn’t) use little h in your own papers.

Speaker: Dongwoo Chung

Room 232