Rolf William Landauer (February 4, 1927 – April 27, 1999) was a

German-American German Americans (german: Deutschamerikaner, ) are Americans who have full or partial German ancestry. With an estimated size of approximately 43 million in 2019, German Americans are the largest of the self-reported ancestry groups by the Unite ...

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 made important contributions in diverse areas of the

thermodynamics Thermodynamics is a branch of physics that deals with heat, work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these quantities is governed by the four laws of th ...

of information processing,

condensed matter Condensed matter physics is the field of physics that deals with the macroscopic and microscopic physical properties of matter, especially the solid and liquid phases which arise from electromagnetic forces between atoms. More generally, the su ...

physics, and the conductivity of disordered media. In 1961 he discovered Landauer's principle, that in any logically irreversible operation that manipulates

information Information is an abstract concept that refers to that which has the power to inform. At the most fundamental level information pertains to the interpretation of that which may be sensed. Any natural process that is not completely random ...

, such as erasing a bit of memory,

entropy Entropy is a scientific concept, as well as a measurable physical property, that is most commonly associated with a state of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodynam ...

increases and an associated amount of

energy In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of hea ...

is dissipated as

heat In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is ...

. This principle is relevant to

reversible computing Reversible computing is any model of computation where the computational process, to some extent, is time-reversible. In a model of computation that uses deterministic transitions from one state of the abstract machine to another, a necessary co ...

quantum information Quantum information is the information of the state of a quantum system. It is the basic entity of study in quantum information theory, and can be manipulated using quantum information processing techniques. Quantum information refers to both t ...

and quantum computing. He also is responsible for the Landauer formula relating the

electrical resistance The electrical resistance of an object is a measure of its opposition to the flow of electric current. Its reciprocal quantity is , measuring the ease with which an electric current passes. Electrical resistance shares some conceptual paralle ...

of a conductor to its scattering properties. He won the

Stuart Ballantine Medal {{notability, date=February 2018 The Stuart Ballantine Medal was a science and engineering award presented by the Franklin Institute, of Philadelphia, Pennsylvania, USA. It was named after the US inventor Stuart Ballantine. Laureates *1947 - Geo ...

of the

Franklin Institute The Franklin Institute is a science museum and the center of science education and research in Philadelphia, Pennsylvania. It is named after the American scientist and statesman Benjamin Franklin. It houses the Benjamin Franklin National Memori ...

, the

Oliver Buckley Prize The Oliver E. Buckley Condensed Matter Prize is an annual award given by the American Physical Society "to recognize and encourage outstanding theoretical or experimental contributions to condensed matter physics." It was endowed by AT&T Bell Lab ...

of the American Physical Society and the

IEEE Edison Medal The IEEE Edison Medal is presented by the Institute of Electrical and Electronics Engineers (IEEE) "for a career of meritorious achievement in electrical science, electrical engineering, or the electrical arts." It is the oldest medal in this fi ...

, among many other honors.

Biography

Landauer was born on February 4, 1927, in Stuttgart,

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

. He emigrated to the United States in 1938 to escape

Nazi Nazism ( ; german: Nazismus), the common name in English for National Socialism (german: Nationalsozialismus, ), is the far-right totalitarian political ideology and practices associated with Adolf Hitler and the Nazi Party (NSDAP) in ...

persecution of

Jew Jews ( he, יְהוּדִים, , ) or Jewish people are an ethnoreligious group and nation originating from the Israelites Israelite origins and kingdom: "The first act in the long drama of Jewish history is the age of the Israelites""T ...

s, graduated in 1943 from Stuyvesant High School, one of

New York City New York, often called New York City or NYC, is the most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the most densely populated major city in the Un ...

's mathematics and science

magnet schools In the U.S. education system, magnet schools are public schools with specialized courses or curricula. "Magnet" refers to how the schools draw students from across the normal boundaries defined by authorities (usually school boards) as school ...

, and obtained his undergraduate degree from Harvard in 1945. Following service in the

US 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 ...

as an

Electrician's Mate Electrician's Mate (abbreviated as EM) is a United States Navy and United States Coast Guard occupational rating. The Electrician's Mate's NOS is B210. History The Navy Electrician rating was established in 1883, then promptly disestablished i ...

, he earned his Ph.D. from Harvard in 1950. He first worked for two years at

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...

, then known as the National Advisory Committee for Aeronautics, at its

Glenn Research Center NASA John H. Glenn Research Center at Lewis Field is a NASA center within the cities of Brook Park and Cleveland between Cleveland Hopkins International Airport and the Rocky River Reservation of Cleveland Metroparks, with a subsidiary facilit ...

, then known as the Lewis Research Center, in Cleveland. At the age of 25, he began a career in semiconductors at

IBM Research IBM Research is the research and development division for IBM, an American multinational information technology company headquartered in Armonk, New York, with operations in over 170 countries. IBM Research is the largest industrial research or ...

. As part of the two-man team responsible for managing IBM's Research Division in the mid-1960s, he was involved in a number of programs, including the company's work on semiconductor lasers. In 1969, he was appointed an

IBM Fellow An IBM Fellow is an appointed position at IBM made by IBM's CEO. Typically only four to nine (eleven in 2014) IBM Fellows are appointed each year, in May or June. Fellow is the highest honor a scientist, engineer, or programmer at IBM can achiev ...

. Much of his research after 1969 related to the kinetics of small structures. He showed that in systems with two or more competing states of local stability, their likelihood depends on noise all along the path connecting them. In electron transport theory, he is particularly associated with the idea, taken from circuit theory, that electric flow can be considered a consequence of current sources as well as applied fields. He was also a pioneer in the area of information handling. His principles have been applied to computers and to the measurement process and are the basis for Landauer's own demonstration that communication, in principle, can be accomplished with arbitrarily little dissipation of energy. Rolf William Landauer died on 27 April 1999 at his home in

Briarcliff Manor Briarcliff Manor () is a suburban village in Westchester County, New York, north of New York City. It is on of land on the east bank of the Hudson River, geographically shared by the towns of Mount Pleasant and Ossining. Briarcliff Manor inc ...

from brain cancer.

Awards and honors

*Fellow,

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operat ...

*Member,

National Academy of Engineering The National Academy of Engineering (NAE) is an American nonprofit, non-governmental organization. The National Academy of Engineering is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of ...

*Member, National Academy of Sciences *Member, European Academy of Sciences and Arts *Fellow,

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, a ...

*Honorary doctorate, Technion in

Israel Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...

*1991 Scott Lecturer at the Cavendish Laboratory at

Cambridge University The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209 and granted a royal charter by Henry III of England, Henry III in 1231, Cambridge is the world' ...

*1992

of the

*Centennial Medal by Harvard in 1993, * Oliver E. Buckley Prize by the American Physical Society (1995) * Moet Hennessey Louis Vuitton (LVMH) Science for Art Prize (1997) *IEEE

Edison Medal The IEEE Edison Medal is presented by the Institute of Electrical and Electronics Engineers (IEEE) "for a career of meritorious achievement in electrical science, electrical engineering, or the electrical arts." It is the oldest medal in this fi ...

(1998) ''For pioneering contributions to the physics of computing and conduction.'' *The Rolf Landauer Medal of the International ETOPIM Association (2009) The range of his work has been recognized in special issues of two journals, 10 years apart: the ''IBM Journal of Research and Development'' (January 1988) and ''Superlattices and Microstructures'' (March/April 1998).

References

External links

The 'Landauer' formulaBio at IEEE Global History NetworkPhysicsWeb ObituaryNature Obituary
{{DEFAULTSORT:Landauer, Rolf Stuyvesant High School alumni Members of the United States National Academy of Sciences 1927 births 1999 deaths IBM Fellows Harvard University alumni Fellow Members of the IEEE German information theorists Members of the United States National Academy of Engineering IEEE Edison Medal recipients 20th-century German physicists Members of the European Academy of Sciences and Arts American information theorists Oliver E. Buckley Condensed Matter Prize winners People from Briarcliff Manor, New York Jewish physicists Jewish emigrants from Nazi Germany to the United States Mathematicians from New York (state) Deaths from brain tumor Fellows of the American Physical Society

Biography

Awards and honors

See also

References

Further reading

External links