Stellar masses and globular clusters: an origin story

Abstract: Stars span a couple orders of magnitude on either side of the maximum mass for a white dwarf, from below the H-burning limit to the mass at which radiation pressure becomes significant. One could say that the changing character of stellar evolution across this range makes our universe an interesting place. But is this situation an accident of fate, or a consequence of underlying physical laws? I will review some old arguments that the limits of the mass range are not accidental. Then, focusing on the formation phases of massive globular clusters, I’ll argue that the peak of the mass function is also tied to the same combination of fundamental constants. If time permits, I’ll speculate on how the extreme conditions of globular cluster formation might cause a flattening of the mass function for massive stars, and comment on how this relates to the properties of extreme high-redshift nebulae.