# Roy Kerr : biography

**Roy Patrick Kerr** CNZM (born 16 May 1934) is a New Zealand mathematician who is best known for discovering the Kerr vacuum, an exact solution to the Einstein field equation of general relativity. His solution models the gravitational field outside an uncharged rotating massive object, including a rotating black hole. by Fulvio Melia, 2009

## Awards

- Hector Medal (1982) "for his work in theoretical physics. ... an exact solution of Einstein's equations of general relativity, ..."
- Hughes Medal (1984) "for his distinguished work on relativity, especially for his discovery of the so-called Kerr Black Hole, which has been very influential."
- Rutherford Medal (1993) "For his outstanding discoveries in the extra-terrestrial world of black holes."
- (2006) "For his fundamental contribution to Einstein's theory of general relativity: ..."
- (2011) "For services to astrophysics."
- Albert Einstein Medal (2013) "for his 1963 discovery of a solution to Einstein's gravitational field equations."

## Private life

Kerr was born in 1934 in Gore, New Zealand. Born into a dysfunctional family, his mother was forced to leave when he was three. When his father went to war, he was sent to a farm. After his father's return from war, they moved to Christchurch. He managed to get into St Andrew's College, a private school, as his father had served under a former headmaster. His solution to Einstein's equations predicted spinning black holes before they were discovered (Martin Rees, Just Six Numbers - The Deep Forces that Shape the Universe, Phoenix, 1999, ISBN 0 75381 022 0, page 41).

Kerr is married to Margaret. They live near Christchurch International Airport.

Kerr was a notable bridge player representing New Zealand internationally. He was co-author of the Symmetric Relay System, a bidding system.

## Notes

## Professional history

Kerr's mathematical talent was first recognized while he was still a high school student at St Andrew's College. Although there was no maths teacher there at the time he was able in 1951 to go straight into third year Mathematics at the Canterbury University College of the University of New Zealand, the precursor to the University of Canterbury. Their regulations did not permit him to graduate until 1954 and so it was not until September 1955 that he moved to the University of Cambridge, where he earned his Ph.D. in 1959. His dissertation concerned the difficult problem of the equations of motion in general relativity.

After a stint as a post-doctoral student at Syracuse University, where Einstein's collaborator Peter Bergmann was professor, he spent some time working for the United States Air Force at Wright-Patterson Air Force Base. Kerr speculated that the "main reason why the US Air Force had created a General Relativity section was probably to show the Navy that they could also do pure research."

In 1962 Kerr moved to the University of Texas at Austin, where in 1963, he discovered the Kerr vacuum solution. In 1965, with Alfred Schild, he introduced the concept of Kerr-Schild spacetimes. During his time in Texas, Kerr supervised four Ph.D. students. Kerr was interviewed about his work on the solution for the book *Cracking the Einstein Code: Relativity and the Birth of Black Hole Physics*, for which he also wrote an afterword.

In 1971, Kerr returned to the University of Canterbury in New Zealand, where he remained until his retirement in 1993. Kerr retired from his position as Professor of Mathematics at the University of Canterbury in 1993 after having been there for twenty-two years, including ten years as the head of the Mathematics department.

In 2008 Kerr was appointed to the Yevgeny Lifshitz ICRAnet Chair in Pescara, Italy.

His life was the subject of the semi-biographical book by Fulvio Melia, published in 2009.

In 2012 it was announced that Kerr would be honoured by the Albert Einstein Society in Switzerland with the 2013 Albert Einstein Medal. He is the first New Zealander to receive the prestiguous award. *Stuff.co.nz*, 20 December 2012