Math Physics Seminar
“Vacuum Energy in Curved Spacetime (Cont.)” by Professor Craig Pryor, Department of Physics & Astronomy, The University of Iowa
Abstract: The small energy density of the vacuum remains one of the great puzzles of theoretical physics. On the one hand, the Casimir effect shows that vacuum energy has observable effects and cannot be simply ignored, yet the theoretically predicted vacuum energy density is many orders of magnitude larger than the value inferred from the observed cosmic acceleration. Taking known physics at face value, zero point fluctuations due to known particles will make at least some contribution to the total vacuum energy. A natural question arrises: how does the vacuum respond to gravity? After a very basic review of the vacuum energy problem, I will present a new method for calculating the vacuum energy in a spherically symmetric static spacetime, such as surrounding a non-rotating massive object. This method is more direct than previously used methods, and provides a simple physical picture of gravity’s effect on the vacuum.