Roy P. Kerr | |
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![]() Kerr in 2024 | |
Born | Kurow, New Zealand | 16 May 1934
Nationality | New Zealand |
Education | St. Andrew's College, Christchurch |
Alma mater |
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Known for | Kerr metric Kerr–Newman metric Kerr–Schild perturbations |
Awards | Hector Medal (1982) Hughes Medal (1984) Rutherford Medal (1993) Albert Einstein Medal (2013) Crafoord Prize (2016) Oskar Klein Medal (2020) |
Scientific career | |
Fields | Mathematics |
Institutions | University of Canterbury Syracuse University |
Thesis | Equations of Motion in General Relativity (1960) |
Roy Patrick Kerr CNZM FRS FRSNZ ( /kɜːr/ ; born 16 May 1934) is a New Zealand mathematician who discovered the Kerr geometry, 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. [1] [2] His solution to Einstein's equations predicted spinning black holes before they were discovered. [3] [4]
Kerr was born in 1934 in Kurow, New Zealand. [5] He was born into a dysfunctional family, and 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 was accepted to St Andrew's College, a private school, as his father had served under a former headmaster. [6] Kerr's mathematical talent was first recognised while he was still a student at St Andrew's College. Although there was no mathematics teacher there at the time, he was able in 1951 to go straight into the third year of mathematics at Canterbury University College, a constituent of the University of New Zealand and 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 PhD in 1959. [7] His dissertation concerned the equations of motion in general relativity. [5]
After a postdoctoral fellowship at Syracuse University, where Einstein's collaborator Peter Bergmann was a professor, [8] [9] 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 U.S. Navy that they could also do pure research." [10]
In 1962, Kerr joined Alfred Schild and his Relativity Group at the University of Texas at Austin. As Kerr wrote in 2009:
Kerr presented to the Symposium his solution to the Einstein field equations. [12] Subrahmanyan Chandrasekhar (Nobel laureate, 1983) is quoted as having said :
In 1965, with Alfred Schild, he introduced the concept of Kerr–Schild perturbations and developed the Kerr–Newman metric. [14] [15] [16] During his time in Texas, Kerr supervised four PhD students.
In 1971, Kerr returned to the University of Canterbury in New Zealand. 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.
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 prestigious award. [22]
In December 2015, the University of Canterbury awarded Kerr an honorary Doctor of Science. [23]
Kerr is married to Margaret. [6] In 2022, after 9 years in Tauranga they returned to Christchurch, where they now reside. Kerr was a notable bridge player representing New Zealand internationally in the mid-1970s. [24] He was co-author of the Symmetric Relay System, a bidding system in contract bridge. [25]
General relativity, also known as the general theory of relativity, and as Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics. General relativity generalizes special relativity and refines Newton's law of universal gravitation, providing a unified description of gravity as a geometric property of space and time, or four-dimensional spacetime. In particular, the curvature of spacetime is directly related to the energy and momentum of whatever present matter and radiation. The relation is specified by the Einstein field equations, a system of second-order partial differential equations.
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Kerr–Schild perturbations are a special type of perturbation to a spacetime metric which only appear linearly in the Einstein field equations which describe general relativity. They were found by Roy Kerr and Alfred Schild in 1965.