A physicist, Pais was a professor at Princeton University in New Jersey, and worked with Albert Einstein and Niels Bohr on theories of elementary particles.
But he is known more to the public as a science historian. His book Subtle Is the Lord: The Science and the Life of Albert Einstein *, considered the definitive biography of Einstein, won the 1983 American Book Award and was named by the New York Times one of the most important books of the year. Pais was born in Amsterdam, and died July 28 in Copenhagen of heart failure. He was 81.