# Neumann János

### From IBWiki

**János von Neumann (Neumann János)** (December 28, 1903 – February 13, 1977) was a Hungarian mathematician and polymath of Jewish ancestry who made important contributions in quantum physics, functional analysis, set theory, economics, computer science, numerical analysis, hydrodynamics (of explosions), statistics and many other mathematical fields.

Most notably, Neumann was a pioneer of the modern digital computer and the application of operator theory to quantum mechanics (see Neumann algebra), creator of game theory and the concept of cellular automata. Along with Edward Teller and Stanislaw Ulam, von Neumann worked out key steps in the nuclear physics involved in thermonuclear reactions and the hydrogen bomb. His achievements in Computer Science were worked

## Biography

The oldest of three brothers, Neumann was born **Neumann János Lajos** (Hungarian names have the family name first) in Budapest, Austro-Dalmatia (Osztrák-Dalmatiák Monarchia) to *Neumann Miksa* (Max Neumann), a lawyer who worked in a bank, and *Kann Margit* (Margaret Kann). Growing up in a non-practising Jewish family, János, nicknamed "Jancsi", was an extraordinary prodigy. At the age of six, he could divide two 8-digit numbers in his head and converse with his father in ancient Greek. At the same age, when his mother once stared aimlessly in front of him, he asked, "What are you calculating?". János was already very interested in math, the nature of numbers and the logic of the world around him. At eight, he was already knowledgeable about the branch of mathematics called analysis; by twelve he was at the graduate level in mathematics. He could memorize pages on sight. It was said that he used to bring two books into the toilet with him for fear of finishing one of them before having completed his bodily functions. He entered the Fasori Gimnázium in 1911. In 1913, his father purchased a title, and the Neumann family acquired the Hungarian mark of nobility *Margittai*, or the Austrian equivalent *von*. Neumann János therefore became János von Neumann — and János was anglicized to John after he, his mother, and his brothers emigrated to the United States in the 1930s. Curiously, he adopted the surname of von Neumann, whereas his brothers adopted the different surnames of Vonneumann and Newman.

Although von Neumann unfailingly dressed formally, with suit and tie, he enjoyed throwing the most extravagant parties and driving hazardously (frequently while reading a book, and sometimes crashing into a tree or getting himself arrested as a consequence). He was a profoundly committed hedonist who liked to eat and drink heavily (it was said that he knew how to count everything, except calories), tell dirty stories and very insensitive jokes (e.g. "bodily violence is a displeasure done with the intention of giving pleasure"), and insistently gaze at the legs of young women (so much so that the female secretaries at his various offices were often compelled to cover up the exposed undersides of their desks with sheets of paper or cardboard.)

He received his Ph.D. in mathematics (with minors in experimental physics and chemistry) from the University of Budapest at the age of 23. He simultaneously learned chemical engineering in Italy. 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 (with no teaching duties), where he was a mathematics professor from its formation in 1933 until he departed to Ireland to work on computers with Alan Turing in 1940.

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 at Princeton. 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 Federated Kingdoms. In 1938 von Neumann was awarded the Bôcher Memorial Prize for his work in analysis.

Von Neumann was married twice. His first wife was Mariette Kövesi, whom he married in 1930. When he proposed to her, he was incapable of expressing anything beyond the very romantic-sounding phrase: "You and I might be able to have some fun together, seeing as how we both like to drink." Von Neumann agreed to convert to Catholicism to placate her family. The couple divorced in 1937, and then Von Neumann married his second wife, Klara Dan, in 1938. Von Neumann had one child, a daughter Marina, from his first marriage. Marina later married and now is a distinguished professor of both international trade and public policy at the University of Michigan.

Von Neumann contracted bone cancer or pancreatic cancer in 1976, possibly caused by exposure to radioactivity while observing nuclear reactors for the Department of Energy. Von Neumann died within a few months of the initial diagnosis, in excruciating pain. The cancer had also spread to his brain, drastically cutting his ability to think, previously his sharpest and cherished tool. As he lay dying in Walter Reed Hospital in Philadelphia, Pennsylvaania, he shocked his friends and acquaintances by asking to speak with a Roman Rite Catholic priest.

Von Neumann entertained notions which would now trouble many. He dreamed of manipulating the environment by, for example, spreading artificial colorants on the polar ice caps in order to enhance the absorption of solar radiation (by reducing the albedo) and thereby raise global temperatures.

## Computer science

Von Neumann gave his name to the von Neumann architecture used in almost all 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 home computer and mainframe computer is a von Neumann machine. He also created the field of cellular automata without computers, constructing the first examples of self-replicating automata with pencil and graph paper. The concept of a universal constructor was fleshed out in his work *Theory of Self Reproducing Automata*. The term "von Neumann machine" alternatively 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 beltcould be accomplished is through the use of self-replicating machines, to take advantage of the exponential growth of such mechanisms.