March 30, 2007	Friday	Rabi-ul-Awwal 10, 1428

PALO ALTO: Paul Joseph Cohen, a leading mathematician who won several of the world’s most prestigious math awards, has died. He was 72. Cohen died on Friday of a rare lung disease, according to Stanford University, where he taught for four decades.Cohen’s honours were remarkable, considering that two prizes represented completely different branches of mathematics.

In 1964, he won the American Mathematical Society’s Bocher Prize for analysis, and in 1966 he won the Fields Medal – the math world’s equivalent of the Nobel Prize – for logic. Cohen also won the 1967 National Medal of Science for his work in logic, and he was an honorary foreign member of the London Mathematical Society.

“Paul Cohen was one of the most brilliant mathematicians of the 20th century,” said Princeton Professor Peter Sarnak, who received his doctorate from Stanford in 1980 under Cohen. “He made mathematics look simple and unified.”

Cohen played piano and violin and sang in a Stanford chorus and Swedish folk group. The son of Polish immigrants, he spoke English, Swedish, French, Spanish, German and Yiddish.

Cohen’s passion was studying extremely difficult, long-standing mathematical problems, such as the Continuum Hypothesis, which is considered central to set theory – the idea that sets of items are the fundamental objects defining all ideas in mathematics.

Cohen shocked the math establishment by proving that the Continuum Hypothesis could not be decided. The notion that conventional mathematics could not prove or disprove concrete and well known assertions caused an uproar among academics.

Cohen was born April 2, 1934, in Long Branch, New Jersey, the fourth and youngest child of Jewish immigrants from Poland. His sister, Sylvia, checked out a library book on calculus for him when he was 9.

Cohen grew up in Brooklyn and graduated from Stuyvesant High School in New York City in 1950. He attended Brooklyn College from 1950 to 1953, but left before receiving a bachelor’s degree, going directly to graduate school at the University of Chicago, where he received a master’s degree in 1954 and a doctorate in 1958.

Cohen joined Stanford in 1961 as an assistant professor of mathematics. He became a full professor in 1964. He retired in 2004 but continued teaching until this quarter.

“He had a very special style, full of enthusiasm and very hands on,” said Angus MacIntyre, a professor of applied logic at Queen Mary, University of London. “He was dauntingly clever.”—AP