John von Neumann

Hungarian American mathematician

• Born: December 28, 1903; Budapest, Hungary
• Died: February 8, 1957; Washington, DC

A brilliant mathematician who formulated the mathematical foundations of quantum theory and computer science, John von Neumann affirmed the importance of independent scientific research during the anti-Communist McCarthy era.

Also known as: János Lajos Neumann; Jancsi Neumann; Johnny von Newman

Primary fields: Mathematics; computer science

Specialty: Quantum mechanics

Early Life

The eldest of three boys, János Lajos Neumann was born in Budapest, Hungary. In the United States, he came to be known universally as John or Johnny, perhaps because he was already known by the Hungarian nickname Jancsi. Von Neumann is one of several Hungarian mathematicians and physicists, including Eugene Wigner, Edward Teller, Leo Szilard, and Dennis Gabor, who have substantially contributed to twentieth-century science. In addition to knowing one another, some of them, including von Neumann, even attended the same Lutheran secondary school: Budapest-Fasori Evangélikus Gimnázium in Hungary.

Von Neumann’s father, Max von Neumann, was a successful banker who was later elevated to the nobility. His family was Jewish and bilingual in Hungarian and German. When von Neumann entered the gymnasium at age ten, he came into contact with Lászlo Rátz, a teacher who perceived his mathematical talents and arranged with his father for special tutoring. Von Neumann worked concurrently on a degree in chemical engineering, awarded by the Eidgenössische Technische Hochschule of Zurich in 1926, and a doctorate in mathematics, which was awarded by the University of Budapest in the same year.

Life’s Work

After completing his education, von Neumann held positions at the University of Berlin and the University of Hamburg. In addition, he also visited Göttingen, where an amazing group of physicists and mathematicians, including David Hilbert, Werner Heisenberg, Max Born, and Erwin Schrödinger, worked at the Institute for Theoretical Physics. Visitors also included notable scientists such as Albert Einstein, Wolfgang Paul, Linus Pauling, J. Robert Oppenheimer, and Norbert Wiener.

In 1930, von Neumann came to the United States as a visiting professor at Princeton University. That year, he married his first wife, Marietta Kövesi. After his marriage, he accepted a permanent position at Princeton in 1931, and in 1933 he was invited to join the university’s Institute for Advanced Study, becoming its youngest faculty member.

Von Neumann and Kövesi’s daughter and only child, Marina, was born in Princeton in 1935. The couple’s marriage ended in divorce about two years later. In 1938, von Neumann visited Hungary and married Klára Dán, who then joined him in Princeton.

In a series of important papers that culminated in a book entitled The Mathematical Foundations of Quantum Mechanics (1944), von Neumann showed that two different theories, Schrödinger’s wave mechanics and Heisenberg’s matrix mechanics, are in fact equivalent. His work on the mathematical foundations of quantum theory had brought him into the small, closely knit circle of theoretical physicists, and so he shared from the beginning an awareness of the technological possibilities of the energy that could be generated by nuclear fission.

Starting in the spring of 1943, physicists and mathematicians were summoned to Los Alamos, New Mexico, where the Manhattan Project had established a research laboratory for the development of an atomic bomb. Von Neumann, already engaged in scientific defense work, particularly in connection with the motions of compressible gases, did not arrive at Los Alamos until the fall of 1943. Once there, he assisted in the development of a method of implosion and a means of calculating the characteristics of nuclear explosions.

Prior to and during the Manhattan Project, von Neumann became interested in problems of turbulence, general dynamics of continua, and meteorological calculation. Because these problems took too long to calculate even with the assistance of desk calculators, he became convinced that the development of electronic computing machines was essential. To this end, he formulated methods of translating mathematical procedures into a language of instructions for a computing machine. He also developed the concept of a universal set of circuits that would enable the machine to solve a great variety of problems; prior to that, each problem required a special and different set of wiring to perform operations in a given sequence. When von Neumann was later awarded the Fermi Prize of the US Atomic Energy Commission (AEC) in 1956, he was especially cited for his work on electronic computing machines.

After World War II, von Neumann became a frequent adviser to the government. After the Soviet Union tested its own atomic bomb, von Neumann supported work on the hydrogen bomb to maintain US ascendancy in the arms race, although he insisted on limiting his role to that of a technical expert. He resisted pressures to join scientists who publicly supported banning nuclear tests and engaged in political lobbying in support of development of the hydrogen bomb.

In 1954, when J. Robert Oppenheimer, formerly the director of the Manhattan Project, was attacked as a security risk and hearings concerning his loyalty were conducted, von Neumann expressed complete confidence in Oppenheimer’s integrity and loyalty. Von Neumann acknowledged that their views concerning the importance of developing the hydrogen bomb differed, but he unequivocally opposed the political harassment of scientists like Oppenheimer. In October 1954, President Dwight Eisenhower offered von Neumann a position on the AEC. According to fellow mathematician and Manhattan Project veteran Stanislaw Ulam, von Neumann was flattered and proud that he, even though foreign born, would be entrusted with such responsibility, but he was concerned about the Oppenheimer affair. Convinced that work on the commission was of great national importance, he accepted the post.

In the summer of 1955, von Neumann slipped in a corridor and injured his left shoulder. Diagnosis of the injury revealed that he had bone cancer. Until the last, he continued to function as a member of the AEC and work on a number of other projects, including the texts for the honorary Silliman lectures to be given at Yale. He was forced to leave his lectures, entitled The Computer and the Brain, unfinished. They were published posthumously in 1958.

Impact

When von Neumann answered a 1954 National Academy of Science questionnaire asking him to name his three most important contributions to mathematics, he selected his work on the mathematical foundations of quantum theory, his ergodic theorems (theorems regarding statistical samples or probability of recurrence), and his theory of operators. In making these selections, von Neumann may have been motivated by a keen desire to maintain the importance of mathematics on a conceptual level in solving the problems of the physical sciences.

Von Neumann was essentially the creator of game theory, a new branch of mathematics. He coauthored a treatise with Oskar Morgenstern, Theory of Games and Economic Behavior (1944) that attempts to schematize mathematically the economic exchange of goods and to solve problems concerning monopoly, oligopoly, and free competition.

In his theory of automata, an area of study in which von Neumann was a pioneer, he effectively demonstrated that in principle it is possible to build machines that can reproduce themselves. His posthumously published lectures, The Computer and the Brain, return to these problems and draw on ideas and terminology from mathematics, electrical engineering, and neurology to outline a theory of representation of logical propositions by electrical networks or nervous systems.

Bibliography

Goldstine, Herman. The Computer from Pascal to von Neumann. Princeton: Princeton UP, 1972. Print. Offers a history of the development of computing technology, written by a very close friend of von Neumann’s.

Hargittai, István. The Martians of Science: Five Physicists Who Changed the Twentieth Century. New York: Oxford UP, 2006. Print. Presents biographies of von Neumann, Theodore von Karman, Leo Szilard, Edward Teller, and Eugene Wigner, five scientists who grew up in Hungary, studied in Germany, and immigrated to the United States to flee the Nazis. Recounts the events of their lives and describes their important scientific discoveries.

Macrae, Norman. John von Neumann: The Scientific Genius Who Pioneered the Modern Computer, Game Theory, Nuclear Deterrence, and Much More. 2nd ed. Providence: American Mathematical Soc., 2000. Print. An accessible account of von Neumann’s personality, life, and work.

Neumann, John von. The Computer and the Brain. Fwd. Ray Kurzweil. 3rd ed. New Haven: Yale UP, 2012. Print. Silliman Memorial Lecture Ser. Von Neumann’s posthumously published lecture series on automata. Includes a foreword by Kurzweil, one by Paul M. and Patricia S. Churchland, and a preface by Neumann’s second wife, Klara von Neumann.

Stern, Nancy. “John von Neumann’s Influence on Electronic Digital Computing, 1944–1946.” Annals of the History of Computers 2.4 (1980): 349–61. Print. Discusses von Neumann’s contribution to the development of the computer.