Frans Pretorius

The South African-Canadian physicist successfully ran the first complete numerical relativity simulation of a binary black hole inspiral and merger. This breakthrough simulation solved a problem that had stumped physicists for decades.

Pretorius is a highly respected professor of physics at Princeton University in New Jersey. At Princeton, he leads research focused on Einstein's theory of general relativity, numerical relativity, and the study of gravitational waves.

Before his 2005 breakthrough, the complex math of Einstein's field equations made modeling the final orbits and collision of two black holes incredibly unstable. His simulation provided the crucial theoretical foundation needed to predict the gravitational wave signals that LIGO later detected in 2015.

To keep the computer simulation from crashing due to mathematical singularities at the event horizons, Pretorius utilized a generalized harmonic formulation of Einstein's equations. He combined this with advanced constraint-damping methods to keep the code mathematically stable through the violent merger phase.