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2021 Dirac Medal awarded to Professor Saul Teukolsky


Former Witsie physicist receives prize for theoretical work essential to the detection of gravitational waves.

Wits alumnus and the Robinson Professor of Theoretical Astrophysics at the California Institute of Technology (Caltech) Professor Saul Teukolsky (BSc 1969, BSc Hons 1970), has been awarded the 2021 Dirac Medal and Prize by the International Centre for Theoretical Physics (ICTP) for his contributions in predicting the properties of gravitational waves that emerge from the collisions of black holes.

Professor Teukolsky receives the prize jointly with Alessandra Buonanno of the Max Planck Institute for Gravitational Physics in Germany; Thibault Damour of the Institute of Advanced Scientific Studies in France; and Frans Pretorius of Princeton University in New Jersey.Professor Saul Teukolsky. Image: Cornell Chronicle

An announcement issued by the ICTP on 9 August 2021 said the four physicists received the medal for establishing the predicted properties of gravitational waves in the curvature of space-time produced when stars or black holes spiral together and merge. Their work was essential for the detection of gravitational waves from these energetic astronomical events by the Laser Interferometer Gravitational-Wave Observatory (LIGO).

"The theoretical work of this year's Dirac Medallists was essential for interpreting the observations from LIGO, which is an unusually subtle experiment," said ICTP director Atish Dabholkar. "Together they provide an impressive check of the accuracy of Einstein's General Theory of Relativity. It is a marvellous tribute to the remarkable power of our theoretical understanding of nature, which seemed too outlandish for observational verification until very recently."

The Dirac Medal, which was first awarded in 1985, is given in honour of the Nobel laureate Paul Dirac, who made fundamental contributions to quantum physics. It is awarded annually on Dirac's birthday, 8 August, to scientists who have made significant contributions to theoretical physics. An international committee of distinguished scientists selects winners from a list of nominated candidates. The Dirac Medal is not awarded to Nobel Laureates, Fields Medallists, or Wolf Foundation Prize winners, although many Dirac medallists have proceeded to win these prestigious prizes.

"I'm very honored to receive this award," Teukolsky told the communications team at Caltech."But quite frankly, this project would have been impossible without the great graduate students and postdocs who have contributed so much."

Professor Teukolsky matriculated from Selborne College in East London and did his undergraduate and postgraduate bachelor of science degrees in mathematics and physics at Wits. He is also a professor at Cornell University and in the early 2000s created a group for simulating the collisions of black holes using Albert Einstein's General Theory of Relativity, and he has led it ever since. He is a co-author of the widely used textbooks Numerical Recipes: The Art of Scientific Computing and Black Holes, White Dwarfs and Neutron Stars: The Physics of Compact Objects. His list of honours also includes membership in the American Academy of Arts and Sciences and the National Academy of Sciences. In 2021, he received the American Physical Society’s Einstein Prize.