RSAA Colloquia / Seminars / Feast-of-Facts: Thursday, 20 December 2018, 11:00-12:00; CSO Common Room

Philip Hopkins

"Cosmic "Dust" (Galaxies, Stars, & Actual Dust!)"

In this talk, I’ll begin by giving a broad overview of the recent work by our group on star and galaxy formation. The most fundamental unsolved problems in these fields all revolve around "feedback" from massive stars (and black holes), which new generations of theoretical models and simulations are now able to incorporate with increasing predictive power. I’ll describe how we (and the community in general) has been able to "build up" models of feedback from protostars through the inter-galactic medium, and how the competition between gravity and these processes naturally gives rise to a variety of "universal" scalings and properties of stars and galaxies. In the second half of the talk, I’ll describe the properties of a remarkable newly-discovered class of instabilities which exist in any system containing dust and gas. These instabilities come in an infinite variety of "flavors" and can have remarkably diverse outcomes. I’ll discuss how this can qualitatively change our predictions for dust growth and evolution; ISM chemistry; stellar abundance patterns; wind-launching in cool stars and AGN torii; dust obscuration; and planet formation.