CCA Colloquium: Daniel Price

Title: Growing pains: the dining habits of stars, planets and black holes

Abstract: To make planets, stars and supermassive black holes, one must rapidly accrete material onto central objects. But the tiniest tangential motion combined with angular momentum conservation sends material into orbit, rather than accreting. Since the 1970s we have understood that Nature solves the angular momentum problem by forming accretion discs, but the angular momentum transport mechanism remains unclear. The past 10 years have given us spectacular resolved observations of discs around both young and old stars, bringing fresh clues. In this talk I’ll explain how pairing 3D simulations with observations helps us solve the “hard” problem of accretion, revealing how stars and planets form, how binary stars interact, black holes grow and how accretion powers luminous transients. I will highlight how particle methods lift the ‘curse of geometry’ when simulating the Universe. Simulations solve old mysteries by showing us things that should have been obvious in hindsight.

March 28, 2025