Daniel Morris Lipkin, 80, a mathematical physicist who lived in Dresher for 46 years, died June 20 of hypertension just after returning home from the 60-year reunion of his Princeton University class.

Born in the Bronx, Mr. Lipkin graduated from Bronx High School of Science in 1946, and earned a degree in physics from Princeton in three years. He received a master's degree in math from the University of Pennsylvania in the early 1950s.

Mr. Lipkin's first job was at Sperry Univac in Philadelphia, where he helped design the world's first computer, said his daughter, Marjie Farber. He was an electrical engineer for 30 years at American Electronic Laboratories in Lansdale, where he held seven patents based on his theories.

In 1983, he left the firm to become a consultant and focus on his true calling: writing papers on quantum mechanics, gravity, and the theory of relativity.

In his spare time, Mr. Lipkin swam a mile daily and played boogie-woogie on any available piano, Farber said.

For 10 years ending in December, Mr. Lipkin nursed his wife, the former Lorraine Schneck, whom he married in New York City in 1954. She had cancer. His last written work was a love poem to her, Farber said.

Surviving in addition to his daughter are sons David A. and Seth W.; a brother; seven grandchildren; and two great-grandchildren.

Services were Thursday. Interment was in Shalom Memorial Park in Lower Moreland.