Rudolf Ludwig Mössbauer (; 31 January 1929 – 14 September 2011) was a German

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 ...

who shared the 1961

Nobel Prize in Physics The Nobel Prize in Physics () is an annual award given by the Royal Swedish Academy of Sciences for those who have made the most outstanding contributions to mankind in the field of physics. It is one of the five Nobel Prizes established by the ...

with

Robert Hofstadter Robert Hofstadter (February 5, 1915 – November 17, 1990) was an American physicist. He was the joint winner of the 1961 Nobel Prize in Physics (together with Rudolf Mössbauer) "for his pioneering studies of electron scattering in atomic nucl ...

for his discovery of the Mössbauer effect, which is the basis for Mössbauer spectroscopy.

Career

Mössbauer was born in

Munich Munich is the capital and most populous city of Bavaria, Germany. As of 30 November 2024, its population was 1,604,384, making it the third-largest city in Germany after Berlin and Hamburg. Munich is the largest city in Germany that is no ...

, where he also studied physics at the

Technical University of Munich The Technical University of Munich (TUM or TU Munich; ) is a public research university in Munich, Bavaria, Germany. It specializes in engineering, technology, medicine, and applied and natural sciences. Established in 1868 by King Ludwig II ...

. He prepared his

Diplom A ''Diplom'' (, from ) is an academic degree in the German-speaking countries Germany, Austria, and Switzerland and a similarly named degree in some other European countries including Albania, Bulgaria, Belarus, Bosnia and Herzegovina, Croatia ...

thesis in the Laboratory of Applied Physics of

Heinz Maier-Leibnitz Heinz Maier-Leibnitz (28 March 1911, in Esslingen am Neckar – 16 December 2000, in Allensbach) was a German physicist. He made contributions to nuclear spectroscopy, coincidence measurement techniques, radioactive tracers for biochemistry and m ...

and graduated in 1955. He then went to the

Max Planck Institute for Medical Research The Max Planck Institute for Medical Research in Heidelberg, Germany, is a facility of the Max Planck Society for basic medical research. Since its foundation, six Nobel Prize laureates worked at the Institute: Otto Fritz Meyerhof (Physiology), ...

Heidelberg Heidelberg (; ; ) is the List of cities in Baden-Württemberg by population, fifth-largest city in the States of Germany, German state of Baden-Württemberg, and with a population of about 163,000, of which roughly a quarter consists of studen ...

. Since this institute, not part of a university, had no right to award a doctorate, Mössbauer remained under the auspices of Maier-Leibnitz, his official thesis advisor, when he passed his PhD exam in Munich in 1958. In his PhD, he discovered the ''recoilless nuclear fluorescence of gamma rays in 191 iridium,'' the Mössbauer effect. His fame grew immensely in 1960 when Robert Pound and Glen Rebka used this effect to prove the

red shift In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and increase in frequency and e ...

of gamma radiation in the gravitational field of the Earth; this Pound–Rebka experiment was one of the first experimental precision tests of

Albert Einstein Albert Einstein (14 March 187918 April 1955) was a German-born theoretical physicist who is best known for developing the theory of relativity. Einstein also made important contributions to quantum mechanics. His mass–energy equivalence f ...

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

. However, the long-term importance of the Mössbauer effect is its use in Mössbauer spectroscopy. Along with

, Rudolf Mössbauer was awarded the 1961 Nobel Prize in Physics. On the suggestion of

Richard Feynman Richard Phillips Feynman (; May 11, 1918 – February 15, 1988) was an American theoretical physicist. He is best known for his work in the path integral formulation of quantum mechanics, the theory of quantum electrodynamics, the physics of t ...

, Mössbauer was invited in 1960 to

Caltech The California Institute of Technology (branded as Caltech) is a private university, private research university in Pasadena, California, United States. The university is responsible for many modern scientific advancements and is among a small g ...

in the USA, where he advanced rapidly from research fellow to senior research fellow; he was appointed a full professor of physics in early 1962. In 1964, his alma mater, the

(TUM), convinced him to go back as a full professor. He retained this position until he became

professor emeritus ''Emeritus/Emerita'' () is an honorary title granted to someone who retirement, retires from a position of distinction, most commonly an academic faculty position, but is allowed to continue using the previous title, as in "professor emeritus". ...

in 1997. As a condition for his return, the faculty of physics introduced a "department" system. This system, strongly influenced by Mössbauer's American experience, was in radical contrast to the traditional, hierarchical "faculty" system of German universities, and it gave the TUM an eminent position in German physics. In 1972, Rudolf Mössbauer went to Grenoble to succeed Heinz Maier-Leibnitz as the director of the Institut Laue-Langevin just when its newly built high-flux research reactor went into operation. After serving a five-year term, Mössbauer returned to Munich, where he found his institutional reforms reversed by overarching legislation. Until the end of his career, he often expressed bitterness over this "destruction of the department." Meanwhile, his research interests shifted to

neutrino A neutrino ( ; denoted by the Greek letter ) is an elementary particle that interacts via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is so small ('' -ino'') that i ...

physics. Mössbauer was regarded as an excellent teacher. He gave highly specialized lectures on numerous courses, including ''Neutrino Physics,'' ''Neutrino Oscillations,'' ''The Unification of the Electromagnetic and Weak Interactions'' and ''The Interaction of Photons and Neutrons With Matter.'' In 1984, he gave undergraduate lectures to 350 people taking the physics course. He told his students: “Explain it! The most important thing is that you can explain it! You will have exams, there you have to explain it. Eventually, you pass them, you get your diploma and you think, that's it! – No, the whole life is an exam, you'll have to write applications, you'll have to discuss with peers... So learn to explain it! You can train this by explaining to another student, a colleague. If they are not available, explain it to your mother – or to your cat!”

Personal life

Mössbauer married Elizabeth Pritz in 1957. They had a son, Peter and two daughters Regine and Susi. They divorced in 1983, and he married his second wife Christel Braun in 1985. Mössbauer died at Grünwald, Germany on 14 September 2011 at 82.

References

External links

* * , a major source for this article * Nobelprize.org. Nobel Media AB 2014. Web. 3 Jan 2015.
Interview with Rudolf Mössbauer (18 minutes)
' {{DEFAULTSORT:Mossbauer, Rudolf 1929 births 2011 deaths Albert Einstein Medal recipients German experimental physicists German Nobel laureates German nuclear physicists Members of the Pontifical Academy of Sciences Nobel laureates in Physics Scientists from Munich Recipients of the Pour le Mérite (civil class) California Institute of Technology faculty Academic staff of the Technical University of Munich Technical University of Munich alumni Technische Universität Berlin alumni Academic staff of Technische Universität Berlin Foreign associates of the National Academy of Sciences Foreign members of the USSR Academy of Sciences Foreign members of the Russian Academy of Sciences Foreign fellows of the Indian National Science Academy German spectroscopists Grand Crosses with Star and Sash of the Order of Merit of the Federal Republic of Germany Fellows of the American Physical Society Max Planck Society alumni