A billionaire hedge fund manager and his wife are donating $60 million to the State University of New York at Stony Brook to fund a center for the study of theoretical physics.

James and Marilyn Simons announced the gift, the largest ever to a school within the SUNY system, at a press conference yesterday with Governor Spitzer in Manhattan. The donation will go toward the creation of the Simons Center for Geometry and Physics, where scholars will study subjects at the cutting edge of physics, including string theory, which scientists believe could yield valuable insights into the properties of the universe.

“We believe there is a chance that work accomplished at the center will significantly change and deepen our understanding of the physical universe and of its basic mathematical structure,” Mr. Simons said.

Mr. Simons has served as the chairman of the math department at Stony Brook and made several multimillion-dollar donations to the Long Island school, including a $25 million gift in 2006. That same year he and private donors from his company, Renaissance Technologies, gave Stony Brook $13 million to continue physics research at the university after the federal government cut its budget. Overall, he and his foundation have donated more than $85 million to Stony Brook. Mrs. Simons also received a Ph.D. in economics from the university.

Mr. Simons amassed his fortune, estimated by Forbes at $5.5 billion, through Renaissance Technologies, which he founded in 1982.

“Jim Simons is a man who knows a good investment when he sees one,” Mr. Spitzer said. “Through his generosity, Jim acknowledges the great potential of SUNY Stony Brook.”

Mr. Spitzer said the state should invest more in its state universities, as well as in the City University of New York. In January, the governor asked that 2,000 full-time faculty be added in a five-year period to state universities and said Stony Brook, along with SUNY-Buffalo, should become a “flagship” institution dedicated to advanced scientific and medical research.