Roy Patrick Kerr

(May 16, 1934– )

Roy PatrickKerr was born in 1934 in Kurow, New Zealand, to Patrick and Edna May Martin Kerr. His parents were divorced before WWII. When his father went to war, he was sent to a farm. After his father's returned from war, they moved to Christchurch. He managed to get into St. Andrew’s College, an independent boarding school, as his father had served under a former headmaster.

Kerr's mathematical talent was first recognized while he was still a high school 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 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, which he did with a MS Mathematics degree, and so it was not until September 1955, that he moved to the University of Cambridge, matriculating at Trinity College, where he earned his PhD in 1959. His dissertation concerned the difficult problem of the equations of motion in general relativity. He submitted his doctoral thesis *Equations of Motion in General Relativity* in 1958 and published the results of the thesis in three papers entitled, *The Lorentz-covariant approximation method in general relativity*, in *Nuovo Cimento i*n 1959.

In 1958, Kerr became a post-doctoral student at Syracuse University, where Einstein's collaborator, Peter Bergmann, was a professor. He spent some time working for the United States Air Force at Wright-Patterson Air Force Base. He writes, “While there, I was invited to join Joshua Goldberg at the Aeronautical Research Laboratory in Dayton Ohio. There was another relativist at the lab, Dr Joseph Schell, who had studied Einstein’s unified field theory under Vaclav Hlavatý. Josh was about to go on study leave to Europe for a few months and did not want to leave Joe by himself. Before he left, Josh and I became interested in the new methods that were entering general relativity from differential geometry at that time. ... In 1962, Goldberg and myself attended a month-long meeting in Santa Barbara. It was designed to get mathematicians and relativists talking to each other. Perhaps the physicists learned a lot about more modern mathematical techniques, but I doubt that the geometers learned much from the relativists. All that aside, I met Alfred Schild at this conference. He had just persuaded the Texas state legislators to finance a Center for Relativity at the University of Texas, and had arranged for an outstanding group of relativists to join. These included Roger Penrose and Ray Sachs, but neither could come immediately, and so I was invited to visit for the 1962–1963 academic year.”

In 1962, Kerr moved to the University of Texas at Austin as a visiting lecturer in the Center for Relativity, where, in 1963, he discovered the Kerr vacuum solution, a set of solutions of the equations of general relativity that described rotating black holes. These "Kerr" black holes rotate at a constant rate, their size and shape depending only on their mass and rate of rotation. If the rotation is zero, the black hole is perfectly round and the solution is identical to the Schwarzschild solution. Kerr commented on his solution, “Everybody who tried to solve the problem was going at it from the front, but I was trying to solve the equation from a different point of view—there were a number of new mathematical methods coming into relativity at the time and Josh [Goldberg] and I had had some success with these. I was trying to look at the whole structure—the Bianchi identities, the Einstein equations and these Tetrads — to see how they fitted together and it all seemed to be pretty nice, and it looked like lots of solutions were going to come out. Then I hit a brick wall. Teddy Newman and Roger Penrose were working on a similar set of methods, but Teddy had come out with this as-yet-unpublished theorem that basically 'proved' that my solution couldn't exist! Luckily, my neighbor, who was playing around with relativity, too, got hold of a preprint and I just scanned through it (I'm a lazy reader) and hit the crucial part which proved to me that my solution could exist! After that, I kept working like mad and found the solution in a few weeks.”

Following the discovery of the Kerr vacuum solution, Kerr was appointed to the University of Texas Mathematics Faculty.

In 1965, in collaboration with Alfred Schild, who was a colleague at the University of Texas, Kerr published “Some algebraically degenerate solutions of Einstein's gravitational field equations” which introduced what are today known as Kerr-Schild spacetimes and the Kerr-Schild metric. During his time in Texas, Kerr supervised four PhD students. They were George Debney. Jr. (1967), David Farnsworth (1967), Michael Mezzino, Jr., and Richard Wilson (1970). Kerr remained at the University of Texas until 1971 when he returned to New Zealand to a chair at the University of Canterbury.

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 *Cracking the Einstein Code* by Fulvio Melia, published in 2009.

In 2012, it was announced that Kerr would be honored by the Albert Einstein Society in Switzerland with the 2013 Albert Einstein Medal. He was the first New Zealander to receive the prestigious award.

In December 2015, the University of Canterbury awarded Kerr an honorary Doctor of Science.

In January 2016, Kerr was awarded the Crafoord Prize in Astronomy by The Royal Swedish Academy of Sciences.

Kerr was a notable bridge player representing New Zealand internationally in the mid 1970s. He won twenty national titles and represented New Zealand at the World Championships. He was co-author (with Paul Marston) of the *Symmetric Relay System*, a bidding system. In the 1990s, he and his wife, Margaret, sold their house and bought a Cavelier 45 sailboat with plans to sail around the world. While the great journey failed to occur, they greatly enjoyed the sailing.

Kerr was married to Joyce Marie Anning (?) and Margaret Anne Silcock (?). Children from the marriages include Susan, Robin Anne, Patrick Seamus Gordon and Sarah Jane Margaret.

**Hector Medal** (1982) "for his work in theoretical physics. ... an exact solution of Einstein's equations of general relativity, ....” Awarded by the Royal Society of New Zealand.

**Hughes Medal** (1984) "The Hughes Medal is awarded to Professor R P Kerr in recognition of his distinguished work on relativity, especially for his discovery of the so-called Kerr black hole. In the early 1960s, Professor Kerr discovered a specific solution to Einstein’s field equations which describes a structure now termed a Kerr black hole. Not only was the solution especially complex, lacking symmetry of previous solutions, but it became apparent that any stationary black hole can be described by Kerr's solution. His work is, therefore, of particular importance to general relativistic astrophysics, and all subsequent detailed work on black holes has depended fundamentally on it. Professor Kerr has made other significant contributions to general relativity theory, but the discovery of the Kerr black hole was so remarkable as to compare with the discovery in physics of a new elementary particle." Awarded by the Royal Society of London.

**Rutherford Medal** (1993) "For his outstanding discoveries in the extra-terrestrial world of black holes." awarded by the Royal Society of New Zealand.

**Marcel Grossmann Award** (2006) "For his fundamental contribution to Einstein's theory of general relativity: ..."

**Companion of The New Zealand Order of Merit** (2011) "For services to astrophysics."

**Albert Einstein Medal **(2013) "for his 1963 discovery of a solution to Einstein's gravitational field equations."

Acknowledgement: Quotes by Roy Kerr and other scientists are from an article by J. J. O'Connor and E. F. Robertson.

Front Row: Remke Gustav Lubben, Hubert Stanley Wall, Gail H. Chamberlia, Pamela G. Hodedon, Dorothy W. Baker, Goldie Horton Porter, Anne Breese Barnes,

Second Row: Hyman Joseph Ettlinger, Robert Lee Moore, Homer Vincent Craig, Evelyn Pressley Jones, Dale Edward Walston, Harry S. Vandiver.

Third Row: Mile Wesley Weaver, Clark Milton Cleveland, **Alfred Schild,** Robert Todd Gregory, **Roy Patrick Kerr**, Robert Ewing Greenwood

Fourth Row: James Mann Hurt, **Ervin J. Prouse**, James E. Scroggs, William T. Guy. Jr., David M. Young, Jr., Roger Cook Osborn, Allen Abbey Goldstela.

Roy Patrick Kerr is young man in middle of the fourth row.