"The Universe Needs Feedback: Problems with the Cosmic Fuel Supply"
Physics Seminar with Dr. Aleks Diamond-Stanic of the University of Wisconsin-Madison
We live in a universe where only 5 percent of the mass-energy is in the form of normal matter; the remainder is attributed to non-baryonic dark matter and dark energy. Furthermore, only 5 percent of the normal matter has managed to form a star or planet by the present day, which is an order of magnitude less than predicted by numerical simulations of galaxy formation. This discrepancy challenges our understanding of what galaxies do with their supply of gas, the fuel for star formation. I will discuss how my research with ground- and space-based telescopes addresses this discrepancy by studying how gas gets into galaxies, how it participates in star formation and black hole growth, and how it is returned to its galactic surroundings via feedback. In the process, we are learning about how radiation, momentum and thermal energy from stars and black holes regulate the fuel supply for star formation, and why we are only 5 percent of the 5 percent.
Tea/cookies will be served before the talk, at 4:15 p.m. in Merrill 204