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Eva Silverstein - The cosmological horizon, macrostates, and microstates

 Eva Silverstein

Talk details

Talk abstract

From the speaker:
“The cosmological horizon plays a key role in cosmology. In the early universe, it creates perturbations, seeding structure starting during inflation from super-horizon modes with wavelengths longer than our observable universe. Current and future observational data contain a wealth of information about this nearly Gaussian state of the macroscopic field modes. The horizon also plays a key role in thought experiments going back to work of Gibbons and Hawking, which suggest an emergent picture of spacetime in which its area in units of Newton’s constant corresponds to an entropy and a count of microstates. Combining several developments in theoretical physics, to be introduced in the talk, we will present recent results reproducing this predicted microstate count in a tractable model.”

Presenter

Eva Silverstein

Eva Silverstein is professor of physics at Stanford University and director of the Modern Inflationary Cosmology collaboration with the Simons Foundation Origins of the Universe initiative. She received her PhD from Princeton University in 1996. She is a Fellow of the American Physical Society, MacArthur Foundation, and American Academy of Arts & Sciences. Her research interests include cosmic inflation, string theory, black-hole physics, and the development of physics-based methods for machine learning. The early universe expanded at a rapidly-accelerating rate, and some imprints of this period are detected in telescopes measuring tiny fluctuations in the light produced at the time when atoms formed. Silverstein’s leading work connects this early period of "cosmic inflation” with the fundamentals of quantum physics and gravity, showing how this is amenable to tests with astronomical observations. Silverstein’s work also addresses the problem of developing more comprehensive laws of quantum physics and gravity, taking into account the accelerated expansion.