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John von Neumann

A separate article covers Saint John Neumann, the American priest.

John von Neumann (Neumann JŠnos) (December 28, 1903February 8, 1957) was a Hungarian-American-German mathematician who made important contributions in quantum physics, set theory, computer science, economics and many other mathematical fields.



The oldest of three children, von Neumann was born Neumann JŠnos Lajos Margittai in Budapest to Neumann Miksa (Max Neumann), a lawyer who worked in a bank, and Kann Margit (Margaret Kann). Growing up in a non-practicing Jewish family, JŠnos, nicknamed "Jancsi", showed incredible memory at an early age, being able to divide eight-digit numbers in his head at the age of six. At the same age, when his mother once stared aimlessly in front of him, he asked, "What are you calculating?". JŠnos was already very interested in math, the nature of numbers and the logic of the world around him. He entered the Lutheran Gymnasium in 1911. In 1913, his father purchased a title, and Neumann JŠnos acquired the German mark of nobility von, becoming JŠnos von Neumann—JŠnos was anglicised to John after he took up residence in the United States in the 1930s.

He received his Ph.D. in mathematics from the University of Budapest at the age of 23. He simultaneously learnt chemistry in Switzerland. Between 1926 and 1930 he was a private lecturer in Berlin, Germany.

Von Neumann was invited to Princeton University in 1930, and was one of four people selected for the first faculty of the Institute for Advanced Study, where he was a mathematics professor from its formation in 1933 until his death.

From 1936 to 1938 Alan Turing was a visitor at the Institute, where he completed a Ph.D. dissertation under the supervision of Alonzo Church. This visit occurred shortly after Turing's publication of his 1936 paper "On Computable Numbers with an Application to the Entscheidungsproblem" which involved the concepts of logical design and the universal machine. Von Neumann must have known of Turing's ideas but it is not clear whether he applied them to the design of the IAS machine ten years later.

In 1937, he became a naturalized citizen of the United States.In 1938 von Neumann was awarded the BŰcher Memorial Prize for his work in analysis.

Von Neumann was the father of game theory and published the classic book Theory of Games and Economic Behavior with Oskar Morgenstern in 1944. He conceived the concept of "MAD" (mutually assured destruction), which dominated American nuclear strategy in the Cold War. He worked in the Theory division at Los Alamos along with Hans Bethe and Victor Weisskopf during World War II as part of the Manhattan Project to develop the first atomic weapons.

One of von Neumann's signature achievements was his rigorous mathematical formulation of quantum mechanics in terms of linear operators on Hilbert spaces. He provided a rigorous foundation for quantum statistical mechanics. He also proposed a proof of the impossibility of hidden variables, showing that quantum mechanics was profoundly different from all previously known theories in physics. His proof contained a conceptual flaw, although subsequently correct proofs were provided by John Bell and others. He apparently held a belief in the role of the observer in creating the collapse of the quantum wave function.

Von Neumann gave his name to the von Neumann architecture used in most non-parallel-processing computers, because of his publication of the concept, though many feel that this naming ignores the contribution of J. Presper Eckert and John William Mauchly who worked on the concept during their work on ENIAC. Virtually every commercially available home computer, microcomputer and supercomputer is a von Neumann machine. He created the field of cellular automata without computers, constructing the first examples of self-replicating automata with pencil and graph paper. The concept was fleshed out in his posthumous work Theory of Self Reproducing Automata. The term von Neumann machine also refers to self-replicating machines. Von Neumann proved that the most effective way large-scale mining operations such as mining an entire moon or asteroid belt can be accomplished is through the use of self-replicating machines, to take advantage of the exponential growth of such mechanisms.

In addition to his work on architecture, he is credited with at least one contribution to the study of algorithms. Donald Knuth cites von Neumann as the inventor, in 1945, of the well known merge sort algorithm, in which the first and second halves of an array are each sorted recursively and then merged together.

He also engaged in exploration of problems in the field of numerical hydrodynamics. With R. D. Richtmyer he developed an algorithm defining artificial viscosity, that proved essential to understanding many kinds of shock waves. It can fairly be said that we would not understand much of astrophysics, and might not even have highly developed jet and rocket engines, without that work. The problem to be solved was that when computers solve hydrodynamic or aerodynamic problems, they try to put too many computational gridpoints at regions of sharp discontinuity (shock waves). The artificial viscosity was a mathematical trick to slightly smooth the shock transition without sacrificing basic physics.

Von Neumann had a mind of great ingenuity and near total recall. He was an extrovert who loved drinking, dancing and having a good time. He had a fun-loving nature with a great love of jokes and humor. He died of cancer in Washington D.C..

The John von Neumann Theory Prize of the Institute for Operations Research and Management Science (INFORMS, previously TIMS-ORSA) is awarded annually to an individual (or sometimes group) who have made fundamental and sustained contributions to theory in operations research and the management sciences.

The IEEE John von Neumann Medal is awarded annually by the IEEE "for outstanding achievements in computer-related science and technology."

The Von Neumann (crater) on Earth's Moon is named after John von Neumann.

Quotations from John von Neumann

"The sciences do not try to explain, they hardly even try to interpret, they mainly make models. By a model is meant a mathematical construct which, with the addition of certain verbal interpretations, describes observed phenomena. The justification of such a mathematical construct is solely and precisely that it is expected to work."

"The most vitally characteristic fact about mathematics is, in my opinion, its quite peculiar relationship to the natural sciences, or more generally, to any science which interprets experience on a higher than purely descriptive level. "


Further Reading

  • von Neumann, John and Arthur W. Burks. 1966. Theory of Self-Reproducing Automata, Univ. of Illinois Press, Urbana IL.
  • von Neumann, John. 1932. "Mathematical Foundations of Quantum Mechanics", Princeton U. Press, Princeton NJ. Transl. by R.T. Beyer from the original German.

Academic Offspring

  • Donald B. Gillies, PhD student of John Von Neumann.
  • John P. Mayberry , PhD student of John Von Neumann.

External links

Last updated: 10-11-2005 13:26:11
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