# "Compact Cauchy horizons in vacuum spacetimes"

## Location

Zoom

Tuesday, April 28, 2020 4:00 PM

Oliver Petersen (Stanford)

Abstract: Moncrief and Isenberg conjectured in 1983 that any compact Cauchy horizon in a smooth vacuum spacetime is a smooth Killing horizon. We present a proof of this conjecture, under the assumption that the surface gravity of the horizon is a non-zero constant. One main ingredient in the proof is a new unique continuation theorem for wave equations through compact horizons.