12:00–1:00 pm Zoom
Julian Muñoz (Harvard & Smithsonian) "Cosmic Dawn: The next frontier in cosmology"
In this talk, I will describe how the cosmic-dawn era, which saw the formation of the first galaxies, holds a wealth of information about cosmology. The light from the first galaxies kickstarted the last major phase transition of our cosmos, as it went from cold and neutral to hot and ionized. This transition will soon be mapped by 21-cm and space telescopes, providing us with a new window to test dark matter and measure the expansion rate. I will provide a brief pedagogical introduction to 21-cm cosmology, and present the first results from the HERA experiment, focusing on their implications. I will also show how to use data from 21-cm as well as from the Hubble and James Webb Space Telescopes to measure the small-scale structure of dark matter beyond the reach of other observables. Finally, I will explain how velocity-induced acoustic oscillations (VAOs) provide us with a new standard ruler, which allows us to measure the expansion rate of our cosmos at z=10-20.
