Roy Patrick Kerr (; born 16 May 1934) is a New Zealand mathematician who discovered the Kerr geometry, an exact solution to the

Einstein field equation In the general theory of relativity, the Einstein field equations (EFE; also known as Einstein's equations) relate the geometry of spacetime to the distribution of matter within it. The equations were published by Einstein in 1915 in the form ...

general relativity General relativity, also known as the general theory of relativity and 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 ...

. His solution models the gravitational field outside an uncharged rotating massive object, including a

rotating black hole A rotating black hole is a black hole that possesses angular momentum. In particular, it rotates about one of its axes of symmetry. All celestial objects – planets, stars (Sun), galaxies, black holes – spin. Types of black holes There a ...

.''Cracking the Einstein Code''
by

Fulvio Melia Fulvio Melia (born 2 August 1956) is an Italian-American astrophysicist, cosmologist and author. He is professor of physics, astronomy and the applied math program at the University of Arizona and was a scientific editor of ''The Astrophysical J ...

, 2009 His solution to Einstein's equations predicted spinning black holes before they were discovered.

Early life and education

Kerr was born in 1934 in Kurow, New Zealand. 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 Christchurch ( ; mi, Ōtautahi) is the largest city in the South Island of New Zealand and the seat of the Canterbury Region. Christchurch lies on the South Island's east coast, just north of Banks Peninsula on Pegasus Bay. The Avon River / ...

. He got into St Andrew's College, a private school, as his father had served under a former headmaster. Kerr's mathematical talent was first recognised 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 University of New Zealand was New Zealand's sole degree-granting university from 1874 to 1961. It was a collegiate university embracing several constituent institutions at various locations around New Zealand. After it was dissolved in 196 ...

, the precursor to the

University of Canterbury The University of Canterbury ( mi, Te Whare Wānanga o Waitaha; postnominal abbreviation ''Cantuar.'' or ''Cant.'' for ''Cantuariensis'', the Latin name for Canterbury) is a public research university based in Christchurch, New Zealand. It was ...

. 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 , mottoeng = Literal: From here, light and sacred draughts. Non literal: From this place, we gain enlightenment and precious knowledge. , established = , other_name = The Chancellor, Masters and Schola ...

, where he earned his

PhD PHD or PhD may refer to: * Doctor of Philosophy (PhD), an academic qualification Entertainment * '' PhD: Phantasy Degree'', a Korean comic series * ''Piled Higher and Deeper'', a web comic * Ph.D. (band), a 1980s British group ** Ph.D. (Ph.D. albu ...

in 1959. His dissertation concerned the equations of motion in general relativity.

Career and research

After a

postdoctoral fellowship A postdoctoral fellow, postdoctoral researcher, or simply postdoc, is a person professionally conducting research after the completion of their doctoral studies (typically a PhD). The ultimate goal of a postdoctoral research position is to p ...

Syracuse University Syracuse University (informally 'Cuse or SU) is a Private university, private research university in Syracuse, New York. Established in 1870 with roots in the Methodist Episcopal Church, the university has been nonsectarian since 1920. Locate ...

, where Einstein's collaborator

Peter Bergmann Peter Gabriel Bergmann (24 March 1915 – 19 October 2002) was a German-American physicist best known for his work with Albert Einstein on a unified field theory encompassing all physical interactions. He also introduced primary and secondar ...

was professor, he spent some time working for the

United States Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...

Wright-Patterson Air Force Base Wright-Patterson Air Force Base (WPAFB) is a United States Air Force base and census-designated place just east of Dayton, Ohio, in Greene County, Ohio, Greene and Montgomery County, Ohio, Montgomery counties. It includes both Wright and Patte ...

. 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 The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...

that they could also do pure research."

Work at Texas and Canterbury

In 1962, Kerr joined

Alfred Schild Alfred Schild (September 7, 1921 – May 24, 1977) was a leading Austrian American physicist, well known for his contributions to the Golden age of general relativity (1960–1975). Biography Schild was born in Istanbul on September 7, 1921. His p ...

and his Relativity Group at the

University of Texas at Austin The University of Texas at Austin (UT Austin, UT, or Texas) is a public research university in Austin, Texas. It was founded in 1883 and is the oldest institution in the University of Texas System. With 40,916 undergraduate students, 11,075 ...

. As Kerr wrote in 2009: :By the summer of 1963,

Maarten Schmidt Maarten Schmidt (28 December 1929 – 17 September 2022) was a Dutch-born American astronomer who first measured the distances of quasars. He was the first astronomer to identify a quasar, and so was pictured on the March cover of ''Time'' mag ...

at Caltech had shown that certain starlike objects (now called

quasar A quasar is an extremely Luminosity, luminous active galactic nucleus (AGN). It is pronounced , and sometimes known as a quasi-stellar object, abbreviated QSO. This emission from a galaxy nucleus is powered by a supermassive black hole with a m ...

s) were actually distant objects emitting enormous amounts of energy. Nobody understood how they could be so bright. In an effort to unravel this mystery, several hundred astronomers, astrophysicists, and general relativists gathered for a conference in Dallas, held in early December that year. This would be the First (of what since then has become the biennial)

Texas Symposium on Relativistic Astrophysics Ivor Robinson (October 7, 1923 – May 27, 2016) was a British-American mathematical physicist, born and educated in England, noted for his important contributions to the theory of relativity. He was a principal organizer of the Texas Symposium on ...

. Kerr presented to the Symposium his solution to the Einstein field equations. S. Chandrasekhar (Nobel laureate, 1983) is quoted as having said : : "In my entire scientific life, extending over forty-five years, the most shattering experience has been the realization that an exact solution of Einstein's equations of general relativity, discovered by the New Zealand mathematician, Roy Kerr, provides the absolutely exact representation of untold numbers of massive black holes that populate the universe" In 1965, with Alfred Schild, he introduced the concept of

Kerr–Schild perturbations 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. Form A genera ...

and developed the

Kerr–Newman metric The Kerr–Newman metric is the most general asymptotically flat, stationary solution of the Einstein–Maxwell equations in general relativity that describes the spacetime geometry in the region surrounding an electrically charged, rotating mas ...

. During his time in Texas, Kerr supervised four PhD students. In 1971, Kerr returned to the

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.

Awards and honours

Hector Medal The Hector Medal, formerly known as the Hector Memorial Medal, is a science award given by the Royal Society Te Apārangi in memory of Sir James Hector to researchers working in New Zealand. It is awarded annually in rotation for different science ...

(1982) "for his work in theoretical physics. ... an exact solution of Einstein's equations of general relativity, ..." *

Hughes Medal The Hughes Medal is awarded by the Royal Society of London "in recognition of an original discovery in the physical sciences, particularly electricity and magnetism or their applications". Named after David E. Hughes, the medal is awarded with ...

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

Companion of the New Zealand Order of Merit The New Zealand Order of Merit is an order of merit in the New Zealand royal honours system. It was established by royal warrant (document), royal warrant on 30 May 1996 by Elizabeth II, Monarchy of New Zealand, Queen of New Zealand, "for those ...

for services to astrophysics (

2011 File:2011 Events Collage.png, From top left, clockwise: a protester partaking in Occupy Wall Street heralds the beginning of the Occupy movement; protests against Libyan dictator Muammar Gaddafi, who was killed that October; a young man celebrate ...

) *

Albert Einstein Medal The Albert Einstein Medal is an award presented by the Albert Einstein Society in Bern. First given in 1979, the award is presented to people for "scientific findings, works, or publications related to Albert Einstein" each year. Recipients ...

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

Crafoord Prize The Crafoord Prize is an annual science prize established in 1980 by Holger Crafoord, a Swedish industrialist, and his wife Anna-Greta Crafoord. The Prize is awarded in partnership between the Royal Swedish Academy of Sciences and the Crafoord Foun ...

(2016
"for fundamental work on rotating black holes and their astrophysical consequences."

Canterbury Distinguished Professor
(2016) *

Oskar Klein Medal The Oskar Klein Memorial Lecture at Stockholm University, dedicated to the memory of the Swedish physicist Oskar Klein (1894-1977), is held annually since 1988 by a prominent physicist, who also receives the Oskar Klein Medal. The lecture is spo ...

(2020) In 2008 Kerr was appointed to the Yevgeny Lifshitz

ICRANet ICRANet, the International Center for Relativistic Astrophysics Network, is an international organization which promotes research activities in relativistic astrophysics and related areas. Its members are four countries and three Universities and ...

Chair in

Pescara Pescara (; nap, label= Abruzzese, Pescàrë; nap, label= Pescarese, Piscàrë) is the capital city of the Province of Pescara, in the Abruzzo region of Italy. It is the most populated city in Abruzzo, with 119,217 (2018) residents (and approxim ...

, Italy.

interviewed Kerr about his work on the solution for the book ''Cracking the Einstein Code: Relativity and the Birth of Black Hole Physics'' published in 2009. Kerr contributed an "Afterword" of two and a half pages. In 2012, it was announced that Kerr would be honoured by the

Albert Einstein Society The Albert Einstein Society was founded by Dr. Max Flückiger on 28 June 1977. Based in Bern, Switzerland, the society awards the Einstein Medal Albert Einstein Medal The Albert Einstein Medal is an award presented by the Albert Einstein Society in Bern. First given in 1979, the award is presented to people for "scientific findings, works, or publications related to Albert Einstein" each year. Recipients ...

. He is the first New Zealander to receive the prestigious award. In December 2015, the

awarded Kerr an honorary

Doctor of Science Doctor of Science ( la, links=no, Scientiae Doctor), usually abbreviated Sc.D., D.Sc., S.D., or D.S., is an academic research degree awarded in a number of countries throughout the world. In some countries, "Doctor of Science" is the degree used f ...

. In May 2016, Kerr was awarded the

in Astronomy by The Royal Swedish Academy of Sciences.

Personal life

Kerr is married to Margaret. In 2022, after 9 years in

Tauranga Tauranga () is a coastal city in the Bay of Plenty region and the fifth most populous city of New Zealand, with an urban population of , or roughly 3% of the national population. It was settled by Māori late in the 13th century, colonised by ...

they returned to

, where they now reside. Kerr was a notable bridge player representing New Zealand internationally in the mid-1970s. He was co-author of the Symmetric Relay System, a

bidding system A bidding system in contract bridge is the set of agreements and understandings assigned to calls and sequences of calls used by a partnership, and includes a full description of the meaning of each treatment and convention. The purpose of bid ...

contract bridge Contract bridge, or simply bridge, is a trick-taking card game using a standard 52-card deck. In its basic format, it is played by four players in two competing partnerships, with partners sitting opposite each other around a table. Millions o ...

."Symmetric" by Andrei Sharko
/ref>

Early life and education

Career and research

Work at Texas and Canterbury

Awards and honours

Personal life

References

External links