A Nobel Prize winner and Cornell University professor has died. Robert Richardson shared the prize with two others in 1996 for their work in 1971 on low-temperature physics involving the isotope helium-3. That discovery helped a wide range of scientific research, from microscopic matters to astrophysics. Richardson joined Cornell in 1968, later becoming a Floyd R. Newman Professor of Physics in 1987. Cornell says Robertson died on Tuesday in Ithaca from complications of a recent heart attack. Robert Richardson was 75.