Bertil Gustafsson (born 1939) is a Swedish applied mathematician and

numerical analyst Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of numerical methods th ...

. He is currently a Professor emeritus in the Department of Information Technology at

Uppsala University Uppsala University ( sv, Uppsala universitet) is a public research university in Uppsala, Sweden. Founded in 1477, it is the oldest university in Sweden and the Nordic countries still in operation. The university rose to significance durin ...

, Sweden. Gustafsson is known for his work in

numerical methods Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of numerical methods th ...

for time-dependent

partial differential equation In mathematics, a partial differential equation (PDE) is an equation which imposes relations between the various partial derivatives of a multivariable function. The function is often thought of as an "unknown" to be solved for, similarly to ...

s and its applications in

fluid dynamics In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases. It has several subdisciplines, including '' aerodynamics'' (the study of air and other gases in motion) ...

. He is the G in GKS (Gustafsson–

Kreiss Kreiss is an American luxury furniture manufacturer, retailer and interior design firm based in Los Angeles. Kreiss is known for pioneering ''The California look''. History Kreiss was founded in 1939 by Murray Kreiss and his two sons Norman and ...

–Sundstrom) theory for initial-boundary value problems which discusses the stability criterion for numerical approximations of initial–boundary value problems. Gustafsson has also authored a couple of books on the topic numerical methods applied to PDE.

Education and career

Gustafsson attended senior high school in

Norrköping Norrköping (; ) is a city in the province of Östergötland in eastern Sweden and the seat of Norrköping Municipality, Östergötland County, about 160 km southwest of the national capital Stockholm, 40 km east of county seat Link� ...

, a city in Sweden. In 1962, he joined Uppsala University, where there was a tradition of prominent mathematicians, including

Arne Beurling Arne Carl-August Beurling (3 February 1905 – 20 November 1986) was a Swedish mathematician and professor of mathematics at Uppsala University (1937–1954) and later at the Institute for Advanced Study in Princeton, New Jersey. Beurling worked ...

and

Lennart Carleson Lennart Axel Edvard Carleson (born 18 March 1928) is a Swedish mathematician, known as a leader in the field of harmonic analysis. One of his most noted accomplishments is his proof of Lusin's conjecture. He was awarded the Abel Prize in 2006 ...

. At Uppsala, Gustafsson developed a strong preference for applied mathematics and when he was in his second year, Heinz-Otto Kreiss joined Uppsala University. It was Kreiss who introduced young Gustafsson to

numerical analysis Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of numerical methods th ...

, and the then new field of

computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes, and development of both hardware and software. Computing has scientific, ...

. In 1971, Gustafsson received his Ph.D. degree under the supervision of Kreiss. His dissertation was on difference methods for hyperbolic equations. Gustafsson has continued to pursue numerical methods in differential equations for most of his career, and much of his early work consisted of applying his theoretical developments to practical problems. These included

weather prediction Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy. On Earth, most weather phenomena occur in the lowest layer of the planet's atmosphere, the t ...

, both in Sweden and at the

National Center for Atmospheric Research The US National Center for Atmospheric Research (NCAR ) is a US federally funded research and development center (FFRDC) managed by the nonprofit University Corporation for Atmospheric Research (UCAR) and funded by the National Science Founda ...

based in Boulder, Colorado. In 2002, he was elected a member of the Royal Swedish Academy of Sciences.

Books

*High Order Difference Methods for Time Dependent PDE, Springer-Verlag (2008). *Time Dependent Problems and Difference Methods, with Heinz-Otto Kreiss and Joseph Oliger, John Wiley (1995).

References

External links

* {{DEFAULTSORT:Gustafsson, Bertil Living people 1939 births Uppsala University faculty Uppsala University alumni Members of the Royal Swedish Academy of Sciences 20th-century Swedish mathematicians