Hans Mueller (1900–1965) was a Swiss

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

and professor at the

Massachusetts Institute of Technology The Massachusetts Institute of Technology (MIT) is a Private university, private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of moder ...

(MIT). He created Mueller calculus. Mueller was born October 27, 1900, in Amriswil, canton

Thurgau Thurgau (; ; ; ), anglicized as Thurgovia, and formally as the Canton of Thurgau, is one of the 26 cantons forming the Swiss Confederation. It is composed of five districts. Its capital is Frauenfeld. Thurgau is part of Eastern Switzerland. I ...

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

. His father was Ernst Müller and mother Mathilde Meier. Hans attended school in

Frauenfeld Frauenfeld (Alemannic German, Alemannic: ''Frauefäld'') is the capital of the Cantons of Switzerland, canton of Canton of Thurgau, Thurgau in Switzerland. The official language of Frauenfeld is (the Swiss variety of Standard) Swiss Standard Ge ...

and proceeded in 1919 to Eidgenössische Technische Hochschule. He graduated with a teacher's diploma for science and mathematics in 1923. In graduate work his advisors were

Peter Debye Peter Joseph William Debye ( ; born Petrus Josephus Wilhelmus Debije, ; March 24, 1884 – November 2, 1966) was a Dutch-American physicist and physical chemist, and Nobel laureate in Chemistry. Biography Early life Born in Maastricht, Neth ...

and Paul Scherrer. In 1925, Mueller and Debye set out for a visit to MIT. Mueller was offered a position as instructor and in time became a popular professor. In 1928 he submitted his dissertation, ''On the Theory of Electric Charge and Coagulation of Colloids'' to ETH for the doctorate in physics. In 1935, he was promoted to

associate professor Associate professor is an academic title with two principal meanings: in the North American system and that of the ''Commonwealth system''. In the ''North American system'', used in the United States and many other countries, it is a position ...

. He was elected in 1936 a Fellow of the

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. (search on year=1936 and institution=Massachusetts Institute of Technology) As a Guggenheim Fellow, he was at the

Cavendish Laboratory The Cavendish Laboratory is the Department of Physics at the University of Cambridge, and is part of the School of Physical Sciences. The laboratory was opened in 1874 on the New Museums Site as a laboratory for experimental physics and is named ...

of Cambridge University in 1937–38. In 1942, he became a full professor. In research, Mueller measured

luminous intensity In photometry, luminous intensity is a measure of the wavelength-weighted power emitted by a light source in a particular direction per unit solid angle, based on the luminosity function, a standardized model of the sensitivity of the huma ...

and studied polarization of light. He wrote several papers on Rochelle salts. The development of his matrix calculus was initially classified, but he made an exposition to the

Optical Society of America Optica, founded as the Optical Society of America (later the Optical Society), is a professional society of individuals and companies with an interest in optics and photonics. It publishes journals, organizes conferences and exhibitions, and ca ...

in 1948. His student Nathan Grier Park III wrote a thesis, ''Matrix Optics'' expounding the method. Hans Mueller died June 10, 1965, in

Belmont, Massachusetts Belmont is a town in Middlesex County, Massachusetts, United States. It is a western suburb of Boston and is part of the Greater Boston metropolitan area. As of the 2020 U.S. census, its population was 27,295, an increase of 10.4% from 2010. H ...

References

{{DEFAULTSORT:Mueller, Hans 1900 births 1965 deaths ETH Zurich alumni Massachusetts Institute of Technology School of Science alumni Massachusetts Institute of Technology School of Science faculty Optical physicists Swiss emigrants to the United States Fellows of the American Physical Society People from Thurgau