Rolf Landauer

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Rolf William Landauer
Born(1927-02-04)February 4, 1927
Stuttgart, Germany
Died April 28, 1999(1999-04-28) (aged 72)
Briarcliff Manor, New York, U.S.
Residence U.S.
Nationality German American
Alma mater Stuyvesant High School
Harvard University
Known for Landauer's principle, Landauer formula (in quantum transport)
Awards Stuart Ballantine Medal (1992)
Oliver E. Buckley Prize (1995)
Edison Medal (1998)
Scientific career
Fields Physicist
Institutions NASA
Doctoral advisor Léon Brillouin and Wendell Furry
Doctoral students None

Rolf William Landauer (February 4, 1927 – April 28, 1999) was a German-American physicist who made important contributions in diverse areas of the thermodynamics of information processing, condensed matter physics, and the conductivity of disordered media. [1] In 1961 he discovered Landauer's principle, that in any logically irreversible operation that manipulates information, such as erasing a bit of memory, entropy increases and an associated amount of energy is dissipated as heat. [1] This principle is relevant to reversible computing, quantum information and quantum computing. He also is responsible for the Landauer formula relating the electrical resistance of a conductor to its scattering properties. He won the Stuart Ballantine Medal of the Franklin Institute, the Oliver Buckley Prize of the American Physical Society and the IEEE Edison Medal, among many other honors. [1]

Physicist scientist who does research in physics

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 causes of phenomena, and usually frame their understanding in mathematical terms. Physicists work across a wide range of research fields, spanning all length scales: from sub-atomic and particle physics, through biological physics, to cosmological length scales encompassing the universe as a whole. The field generally includes two types of physicists: experimental physicists who specialize in the observation of physical phenomena and the analysis of experiments, and theoretical physicists who specialize in mathematical modeling of physical systems to rationalize, explain and predict natural phenomena. Physicists can apply their knowledge towards solving practical problems or to developing new technologies.

Thermodynamics branch of physics concerned with heat, work, temperature, and thermal or internal energy

Thermodynamics is the branch of physics that has to do with heat and temperature and their relation to energy and work. The behavior of these quantities is governed by the four laws of thermodynamics, irrespective of the composition or specific properties of the material or system in question. The laws of thermodynamics are explained in terms of microscopic constituents by statistical mechanics. Thermodynamics applies to a wide variety of topics in science and engineering, especially physical chemistry, chemical engineering and mechanical engineering.

Landauer's principle is a physical principle pertaining to the lower theoretical limit of energy consumption of computation. It holds that "any logically irreversible manipulation of information, such as the erasure of a bit or the merging of two computation paths, must be accompanied by a corresponding entropy increase in non-information-bearing degrees of freedom of the information-processing apparatus or its environment".



Landauer was born on February 4, 1927, in Stuttgart, Germany. He emigrated to the United States in 1938 to escape Nazi persecution of Jews, graduated in 1943 from Stuyvesant High School, one of New York City's mathematics and science magnet schools, and obtained his undergraduate degree from Harvard in 1945. Following service in the US Navy as an Electrician's Mate, he earned his Ph.D. from Harvard in 1950. [2]

Stuttgart Place in Baden-Württemberg, Germany

Stuttgart is the capital and largest city of the German state of Baden-Württemberg. Stuttgart is located on the Neckar river in a fertile valley known locally as the "Stuttgart Cauldron." It lies an hour from the Swabian Jura and the Black Forest. Its urban area has a population of 609,219, making it the sixth largest city in Germany. 2.7 million people live in the city's administrative region and another 5.3 million people in its metropolitan area, making it the fourth largest metropolitan area in Germany. The city and metropolitan area are consistently ranked among the top 20 European metropolitan areas by GDP; Mercer listed Stuttgart as 21st on its 2015 list of cities by quality of living, innovation agency 2thinknow ranked the city 24th globally out of 442 cities and the Globalization and World Cities Research Network ranked the city as a Beta-status world city in their 2014 survey.

Germany Federal parliamentary republic in central-western Europe

Germany, officially the Federal Republic of Germany, is a country in Central and Western Europe, lying between the Baltic and North Seas to the north, and the Alps to the south. It borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, France to the southwest, and Luxembourg, Belgium and the Netherlands to the west.

Emigration is the act of leaving a resident country or place of residence with the intent to settle elsewhere. Conversely, immigration describes the movement of persons into one country from another. Both are acts of migration across national or other geographical boundaries.

He first worked for two years at NASA, then known as the National Advisory Committee for Aeronautics, and at the age of 25 began a career in semiconductors at IBM. 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.

NASA space-related agency of the United States government

The National Aeronautics and Space Administration is an independent agency of the United States Federal Government responsible for the civilian space program, as well as aeronautics and aerospace research.

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

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 [3] .

Rolf William Landauer died on 28 April 1999 at his home in Briarcliff Manor from brain cancer. [2] [4]

Awards and honors

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 Sciences (NAS), the National Academy of Medicine, and the National Research Council.

European Academy of Sciences and Arts academy of sciences

The European Academy of Sciences and Arts is a learned society of around 1,700 top scientists and artists who approach the questions facing Europe and the globe in various colloquia and publications. Among its members are 31 Nobel laureates. Not focused on financial gain, the academy is funded by the European Union, Austria, public agencies and private sponsors, while remaining ideologically and politically independent.

American Academy of Arts and Sciences United States honorary society and center for independent policy research

The American Academy of Arts and Sciences is one of the oldest learned societies in the United States. It is devoted to the advancement and study of the key societal, scientific, and intellectual issues of the day.

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).

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  1. 1 2 3 Bennett, Charles H.; Fowler, Alan B. (2009). "Rolf W. Landauer (1927 - 1999) A biographical memoir" (PDF). Biographical Memoirs v. 91 (2009). National Academy of Sciences. doi:10.17226/12776. ISBN   978-0-309-14560-2.
  2. 1 2 Johnson, George (April 30, 1999). "Rolf Landauer, Pioneer in Computer Theory, Dies at 72". The New York Times. Rolf W. Landauer, who helped solidify the slippery concept of information and bring it firmly into the mainstream of physics, died on Wednesday at his home in Briarcliff Manor, N.Y. He was 72. He died of brain cancer, his family said.
  3. R. Landauer, ‘Minimal Energy Requirements in Communication’, Science 272, 1914 (1996).
  4. Fowler, Alan; Bennett, Charles H.; Keller, Seymour P.; Imry, Yoseph (October 1999). "Obituary: Rolf William Landauer". Physics Today. 52 (10): 104–105. Bibcode:1999PhT....52j.104F. doi:10.1063/1.882874. Archived from the original on 2013-10-09.

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