Mathematician Paul Olum, who worked on the Manhattan Project in World War II, became chair of the mathematics department at Cornell University and then provost and president of the University of Oregon, died Jan. 19 in Sharon, Mass. He was 82.

In the early 1940s, while working as a physicist at Princeton University, Olum joined Hans Bethe, the eminent Cornell physicist, at Los Alamos on the project to develop the first nuclear weapon. He earned his M.A. in physics from Princeton in 1942 but switched his Þeld to mathematics, earning his Ph.D. in mathematics from Harvard in 1947. After a two-year stay at the Institute for Advanced Study at Princeton, he arrived at Cornell as an assistant professor in 1949.

At the time, Olum was the only representative of the burgeoning Þeld of algebraic topology in the Cornell mathematics department. In the following years, he built the Þeld at Cornell into one of the strongest in the nation.

In 1962 Olum initiated the Topology Festival, an annual regional professional gathering at which the major developments in the subject were presented. This became the most prestigious topology conference in the country and is still an annual event at Cornell.

From 1963 to 1966, Olum served as department chair. He was an active participant in faculty governance and in 1971 was elected to the Cornell Board of Trustees. In 1974, he moved to the University of Texas as dean of the arts college. Later, he was named provost, then president, of the University of Oregon, retiring at the age of 70.

Olum's contributions to mathematics were all in the area of algebraic topology, more speciÞcally the subÞeld of obstruction theory. He was a pioneer in developing a comprehensive theory of algebraic measures known as obstructions. His 1950 paper on obstructions, which appeared in the Annals of Mathematics , is still one of the standard references on the subject. His work has had inßuence far beyond his technical specialty.

Olum was born Aug. 16, 1918, in Binghamton, N.Y., and he liked to tell a story about how he became involved in mathematics. He began his graduate career as a very bright physics student but was entirely intimidated by his ofÞce mate, who seemed so much more able. Olum felt that if that was the standard for a good physics graduate student, then the Þeld was clearly too difÞcult for him, and he opted to go into mathematics. The office mate was Richard Feynman, who became a Nobel laureate and remained a close friend until his death in 1988.

Following his retirement from the University of Oregon in 1990, Olum moved to Athens, Greece, to be with his friend Margarita Papandreou, former wife of the Greek prime minister. In 1996, he returned to the United States to live with his son, Ken, in Sharon, Mass.

Olum's wife, Vivian, who was associate professor of counseling psychology at the University of Oregon, died in 1986. Besides his son, he is survived by his daughter, Joyce Galaski, her husband, Philippe, and their children, Rebecca, Deborah and Aviva, of Amherst, Mass.

Funeral services were held at Bell Hall at the University of Oregon, Jan. 24, and memorial services were at the university's Paul Olum Atrium in Willamette Hall, Jan. 25.