WFU Physics Colloquium

TITLE: Particle Production and Vacuum Polarization Effects in Cosmological and Black Hole Spacetimes

SPEAKER: Professor Paul R. Anderson ,

TIME: Thursday Oct. 4, 2007 at 4:00 PM

PLACE: George P. Williams, Jr. Lecture Hall, (Olin 101)

If a quantum field is coupled to a classical field such as the electromagnetic field or the gravitational field then both particle production and vacuum polarization effects can occur. Particle production can occur if the classical field varies in time. Important examples include the reheating which occurs in many inflationary models after the universe stops expanding exponentially, and black hole evaporation. It is possible to have an energy density and pressure of the quantum field which is not associated with particles and occurs even if the field is in the vacuum state. This is called vacuum polarization. Some effects of vacuum polarization near the event horizons of black holes will be discussed.