Person: Ulam, Stanislaw Marcin
Stan Ulam solved the problem of how to initiate fusion in the hydrogen bomb. He also devised the 'MonteCarlo method' widely used in solving mathematical problems using statistical sampling.
Mathematical Profile (Excerpt):
 At the age of ten, Ulam entered the gymnasium in Lwów and, about this time, he became interested first in astronomy and then in physics.
 However this required an understanding of mathematics and so, at age 14, he began to study mathematics from books, going well beyond the school level mathematics he was learning.
 Now with interests in astronomy, physics and mathematics, Ulam entered the Polytechnic Institute in Lwów.
 Ulam obtained his Ph.D. from the Polytechnic Institute in Lwów in 1933 where he studied under Banach.
 Ulam, in 1930, strengthened Banach's result by proving it without using the Generalised Continuum Hypothesis.
 In 1935 Ulam received an invitation from von Neumann to visit the Institute for Advanced Study in Princeton for a few months.
 In 1940 Ulam was appointed as an assistant professor at the University of Wisconsin.
 In 1943 Ulam became an American citizen.
 This twostage radiation implosion design, which became known as the TellerUlam configuration, led to the creation of modern thermonuclear weapons.
 Ulam, with J C Everett, also proposed the 'Orion' plan for nuclear propulsion of space vehicles.
 A crippling technical weakness coupled with an extraordinarily creative imagination is the drama of Stan Ulam.
 While Ulam was at Los Alamos, he developed the 'MonteCarlo method' which searched for solutions to mathematical problems using a statistical sampling method with random numbers.
 Ulam's writing include A collection of mathematical problems (1960), Sets numbers and universes (1974) and Adventures of a Mathematician (1976).
 Thus Ulam has always had a very hard time bringing himself to write anything for publication, either in long hand or with a typewriter.
Born 13 April 1909, Lemberg, Austrian Empire (now Lviv, Ukraine). Died 13 May 1984, Santa Fe, New Mexico, USA.
View full biography at MacTutor
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Origin Ukraine
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References
Adapted from other CC BYSA 4.0 Sources:
 O’Connor, John J; Robertson, Edmund F: MacTutor History of Mathematics Archive