Simeon Adlow Friedberg, longtime Carnegie Mellon University professor and researcher who chaired the school's physics department during the 1970s, died Sunday in his Squirrel Hill home of Parkinson's disease. He was 80.

A frequent lecturer and author of scores of academic works, Dr. Friedberg was remembered by colleagues yesterday as a pioneer in his research specialty of low-temperature magnetism. They said he also influenced scores of doctoral students he supervised through several decades.

Dr. Friedberg grew up in Squirrel Hill, graduating from Allderdice High School in 1942. He entered Harvard College at age 16, but his studies were interrupted by World War II and his entry into the Army. He completed officer candidate school in Fort Benning as a second lieutenant and served in the Army occupation of Japan for a year starting in 1945.

Back at Harvard, he graduated with a chemistry degree in 1947. He did his graduate studies at what was then Carnegie Institute of Technology, receiving a master's degree in chemistry and physics in 1948 and a doctorate in physics in 1951.

Dr. Friedberg was a Fulbright scholar, studying in Leiden, Netherlands, in 1951 and 1952.

He joined the Carnegie Tech physics department as an instructor in 1952, the start of a 42-year career at what later became Carnegie Mellon. He was a professor of physics and department chair from 1972 to 1980, his family said.

"He was one of the pioneers of bringing these materials to extremely low temperatures near absolute zero and then studying their magnetic properties at those temperatures," said Carnegie Mellon physics professor Stephen Garoff. "The fundamental research he did fed into the development of new and more powerful magnets as well as understanding superconducting materials."

With a precise but unassuming manner, he also found ways to connect with students in hard science. Near the end of his career, the class in one doctoral course in statistical mechanics "spontaneously got up and applauded," colleague Robert Suter recalled.

"What that said about him was he was a consummate gentleman," he said.

Others recalled Dr. Friedberg's love of reading and the great number of science volumes that lined the walls of his office and home.

"He had an enormous library of physics books and was always able to use them to give out a good answer to just about any question you might ask about his area of physics," said Robert Schumacher, a professor emeritus at Carnegie Mellon. "Assuming he didn't know the answer off the top of his head."

His family recalled Dr. Friedberg's wide range of outside interests, from photography to classical music to Woody Allen movies.

Surviving are his wife of 55 years, Joan Brest Friedberg of Squirrel Hill; two daughters, Betsy Friedberg of Melrose, Mass., and Susan Friedberg Kalson of Squirrel Hill; a son, Aaron Friedberg of Princeton, N.J.; and seven grandchildren.

The funeral will be at 2 p.m. today in Rodef Shalom Temple, 4905 Fifth Ave., Shadyside. Visitation will be from 1 to 2 p.m. Interment will be in West View Cemetery of Rodef Shalom Congregation.

Contributions may be made to Carnegie Mellon University, directed to the Science Library, 5000 Forbes Ave., Pittsburgh 15213. Arrangements are by Ralph Schugar Chapel.