Sigve Tjøtta (1 March 1930 – 28 August 2023) was a Norwegian

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

Early life

He was born in

Klepp Klepp is a List of municipalities of Norway, municipality in Rogaland county, Norway. It is located in the Traditional districts of Norway, traditional district of Jæren. The administrative centre of the municipality is the village of Kleppe. O ...

. He took the

cand.real. Candidate ( or ) is the name of various academic degrees, which are today mainly awarded in Scandinavia. The degree title was phased out in much of Europe through the 1999 Bologna Process, which has re-formatted academic degrees in Europe. The de ...

degree in 1954 and the

dr.philos. A Doctor of Philosophy (PhD, DPhil; or ) is a terminal degree that usually denotes the highest level of academic achievement in a given discipline and is awarded following a course of graduate study and original research. The name of the deg ...

degree in 1960, both at the

University of Oslo The University of Oslo (; ) is a public university, public research university located in Oslo, Norway. It is the List of oldest universities in continuous operation#Europe, oldest university in Norway. Originally named the Royal Frederick Univ ...

. His doctoral thesis was ''On Some Non-linear Effects in Sound Fields, with Special Emphasis on the Generation of Vorticity and the Formation of Streaming Patterns''. He worked as a

research assistant A research assistant (RA) is a researcher employed, often on a temporary contract, by a university, research institute, or privately held organization to provide assistance in academic or private research endeavors. Research assistants work under ...

in Oslo from 1954 to 1956, 1957 to 1958 and 1959 to 1960. In between he studied at

Brown University Brown University is a Private university, private Ivy League research university in Providence, Rhode Island, United States. It is the List of colonial colleges, seventh-oldest institution of higher education in the US, founded in 1764 as the ' ...

from 1956 to 1957 and at the

Max Planck Institute The Max Planck Society for the Advancement of Science (; abbreviated MPG) is a formally independent non-governmental and non-profit association of German research institutes. Founded in 1911 as the Kaiser Wilhelm Society, it was renamed to the M ...

. Among his advisors were

Johan Peter Holtsmark Johan Peter Holtsmark (13 February 1894 – 10 December 1975) was a Norwegian physicist, who studied spectral line broadening and electron scattering. In 1929, while at the Norwegian Institute of Technology, Holtsmark established acoustics resea ...

Career

He was appointed

docent The term "docent" is derived from the Latin word , which is the third-person plural present active indicative of ('to teach, to lecture'). Becoming a docent is often referred to as habilitation or doctor of science and is an academic qualifi ...

at the

University of Bergen The University of Bergen () is a public university, public research university in Bergen, Norway. As of 2021, the university had over 4,000 employees and 19,000 students. It was established by an act of parliament in 1946 consolidating several sci ...

in 1960, and was promoted to professor in 1963. He succeeded

Oddvar Bjørgum Oddvar is a given name. Notable people with the given name include: *Oddvar Barlie (1929–2017), Norwegian sport wrestler *Oddvar Berrefjord (1918-1999), Norwegian jurist and politician *Oddvar Brå (born 1951), Norwegian former cross-country skie ...

, and had responsibility for the university's education in

applied mathematics Applied mathematics is the application of mathematics, mathematical methods by different fields such as physics, engineering, medicine, biology, finance, business, computer science, and Industrial sector, industry. Thus, applied mathematics is a ...

. His fields of research include plasma,

nonlinear acoustics Nonlinear acoustics (NLA) is a branch of physics and acoustics dealing with sound waves of sufficiently large amplitudes. Large amplitudes require using full systems of governing equations of fluid dynamics (for sound waves in liquids and gases) ...

, hydroacoustics and acoustic streaming. He was also the dean of the Faculty of Mathematics and Natural Sciences from 1975 to 1977, and has held positions in

NAVF The Norwegian Research Council for Science and the Humanities (Norges almenvitenskapelige forskningsråd, NAVF) was one of Norway's five research councils. It was established in 1949. NAVF was responsible for funding basic research in all discipline ...

, NTVF, and in the national committee of the International Union of Theoretical and Applied Mechanics. He has also been a visiting scholar at the

University of Texas The University of Texas at Austin (UT Austin, UT, or Texas) is a public research university in Austin, Texas, United States. Founded in 1883, it is the flagship institution of the University of Texas System. With 53,082 students as of fall 2 ...

Personal life

Tjøtta married Jacqueline Naze, a colleague, in 1964—they barely survived a car crash sustained on their

honeymoon A honeymoon is a vacation taken by newlyweds after their wedding to celebrate their marriage. Today, honeymoons are often celebrated in destinations considered exotic or romantic. In a similar context, it may also refer to the phase in a couple ...

. They have since done extensive research together. After retirement from the professor chair, the couple moved to

Oslo Oslo ( or ; ) is the capital and most populous city of Norway. It constitutes both a county and a municipality. The municipality of Oslo had a population of in 2022, while the city's greater urban area had a population of 1,064,235 in 2022 ...

. Tjøtta's most prominent hobby is

long-distance running Long-distance running, or endurance running, is a form of continuous running over distances of at least . Physiologically, it is largely aerobic in nature and requires stamina as well as mental strength. Within endurance running come two di ...

. He discovered his talent during a stay in the United States, where

jogging Jogging is a form of trotting or running at a slow or leisurely pace. The main intention is to increase physical fitness with less stress on the body than from faster running but more than walking, or to maintain a steady speed for longer periods ...

was popular. He ran the

marathon The marathon is a long-distance foot race with a distance of kilometres ( 26 mi 385 yd), usually run as a road race, but the distance can be covered on trail routes. The marathon can be completed by running or with a run/walk strategy. There ...

in 3:17.02 hours at the age of 66, and the

half marathon A half marathon is a road running event of —half the distance of a marathon. It is common for a half marathon event to be held concurrently with a marathon or a 5K race, using almost the same course with a late start, an early finish, or shortcu ...

in 1:43.09 hours at the age of 75. He died in August 2023, aged 93.

Honors

Together with his wife, Tjøtta won a prize in

underwater acoustics Underwater acoustics (also known as hydroacoustics) is the study of the propagation of sound in water and the interaction of the mechanical waves that constitute sound with the water, its contents and its boundaries. The water may be in the oce ...

from the

French Academy of Sciences The French Academy of Sciences (, ) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific method, scientific research. It was at the forefron ...

. He is a fellow of the

Acoustical Society of America The Acoustical Society of America (ASA) is an international scientific society founded in 1929 dedicated to generating, disseminating and promoting the knowledge of acoustics and its practical applications. The Society is primarily a voluntary org ...

, and a member of the

Norwegian Academy of Science and Letters The Norwegian Academy of Science and Letters (, DNVA) is a learned society based in Oslo, Norway. Its purpose is to support the advancement of science and scholarship in Norway. History The Royal Frederick University in Christiania was establis ...

. In 2002 he was decorated as a Knight, First Class of the

Royal Norwegian Order of St. Olav The Royal Norwegian Order of Saint Olav (; or ''Sanct Olafs Orden'', the old Norwegian name) is a Norwegian order of chivalry instituted by King Oscar I on 21 August 1847. It is named after King Olav II, known to posterity as St. Olav. Just be ...

References

{{DEFAULTSORT:Tjotta, Sigve 1930 births 2023 deaths People from Klepp Norwegian mathematicians University of Oslo alumni Norwegian expatriates in the United States Norwegian expatriates in Germany Academic staff of the University of Oslo Academic staff of the University of Bergen Members of the Norwegian Academy of Science and Letters Brown University alumni