Two noted mathematicians who helped found the Mathematical Sciences Research Institute on the UC Berkeley campus were named by a Norwegian academy Thursday to receive a new international award considered the equivalent of a Nobel prize for math.

Isadore M. Singer of the Massachusetts Institute of Technology and Sir Michael F. Atiyah of the University of Edinburgh, whose work forged new and powerful links between mathematics and physics, are receiving the Abel Prize and will share the $875,000 award, the Norwegian Academy of Science and Letters announced.

The two were cited for discovering and proving a crucial mathematical concept called the "index theorem," which the academy called "one of the great landmarks of 20th century mathematics."

Both men were deeply involved in creating the independent Berkeley math institute, according to David Eisenbud, its director, and both have served on its board of trustees since the institute's founding in 1979.

Their work, in fact, has resulted in a weeklong international workshop, now under way at the institute, on geometry and mathematical physics with 100 scientists and mathematicians in attendance, Eisenbud said.

"One of the most remarkable developments in my scientific lifetime has been the new fields of interaction between physics and mathematics, and these two men have been responsible for a major part of that development," Eisenbud said.

The Norwegian government awards the Nobel Peace Prize each year, and the Abel Prize is also an annual award. It was created last year by a government- appointed committee of the nation's science academy to commemorate the 100th anniversary of the birth of Niels Henrik Abel, a promising and prolific Norwegian mathematician who died of tuberculosis when he was 26.

Singer, who is 80, is an institute professor at MIT and a member of the National Academy of Sciences. He won the National Medal of Science in 1983 when he was a professor at UC Berkeley, and he has served on the White House Science Council.

Atiyah, 75, has been president of Britain's Royal Society and president of the international Pugwash Conferences on Science and World Affairs. He has been a professor at both the University of Oxford and the University of Cambridge.