Abraham Pais (; May 19, 1918 – July 28, 2000) was a Dutch-American physicist and science historian. Pais earned his Ph.D. from University of Utrecht just prior to a Nazi ban on Jewish participation in Dutch universities during World War II. When the Nazis began the forced relocation of Dutch Jews, he went into hiding, but was later arrested and saved only by the end of the war. He then served as an assistant to Niels Bohr in Denmark and was later a colleague of Albert Einstein at the Institute for Advanced Study in Princeton, New Jersey. Pais wrote books documenting the lives of these two great physicists and the contributions they and others made to modern physics. He was a physics professor at Rockefeller University until his retirement.
Early life
Pais was born in Amsterdam, the first child of middle-class Dutch-Jewish parents. His father, Isaiah "Jacques" Pais, was the descendant of Sephardic Jewish immigrants from Portugal to the Low Countries around the beginning of the 17th century. His mother, Kaatje "Cato" van Kleeff, was the daughter of an Ashkenazi Jewish diamond cutter. His parents met while studying to become elementary-school teachers. They both taught school until his mother quit when they married on December 2, 1916. His only sibling, Annie, was born on November 1, 1920. During Pais's childhood his father was a principal of both a secular school and a Hebrew school.
Pais was a bright student and a voracious reader during his early education and said he had a happy childhood and felt integrated in Dutch society. At age twelve he passed examinations to enter a Hogere Burgerschool and attended a school in Amsterdam with a five-year curriculum of basic subjects. He passed his final examinations as number one in his class. He graduated with a working knowledge of English, French, and German.
Higher education
In the fall of 1935 Pais began his studies at the University of Amsterdam without a clear idea regarding his desired career. With an interest in the exact sciences, he gradually gravitated to chemistry and physics as major subjects, and mathematics and astronomy as minor subjects. In the winter of 1936/1937 his career goals were defined by two guest lectures by George Uhlenbeck, professor of theoretical physics at University of Utrecht. Pais was fascinated by Uhlenbeck's discussion of Enrico Fermi's incorporation of the neutrino into the theory of beta radiation.
On February 16, 1938, Pais was awarded two Bachelor of Science degrees in physics and mathematics, with minors in chemistry and astronomy. He began attending graduate courses in Amsterdam, including those in physics. He soon became disappointed by the only professor there in theoretical physics, (the son of the 1910 Nobel laureate Johannes Diderik van der Waals), whom he found dull and averse to the new developments in physics. Pais soon wrote to Uhlenbeck at Utrecht and was granted an interview. During the remainder of the spring term he discontinued attending classes in Amsterdam and made several trips to visit Uhlenbeck in his laboratory.
In the fall of 1938 Pais enrolled for graduate classes at University of Utrecht. Uhlenbeck, however, spent that term as a visiting professor at Columbia University in New York City. He left Pais with the use of his laboratory and a list of topics to study and work on. Pais was soon exposed to other prominent Dutch physicists and areas of research in experimental physics. He became well-acquainted with Hendrik Anthony Kramers, a physics professor at Leiden University who lectured at Utrecht twice a week on quantum physics. When Uhlenbeck returned from America, he brought news of a meeting he had attended in Washington, D.C., in which Niels Bohr and Enrico Fermi had first made public their news about nuclear fission. Uhlenbeck also announced that he would be leaving in the summer of 1939 for a professorship at University of Michigan, Ann Arbor.
In the fall of 1939 Pais dedicated himself to preparing for his master's degree. Utrecht experimental physicist Leonard Salomon Ornstein provided him guidance in his independent physics studies. He was also influenced then by discussions with Léon Rosenfeld of the University of Liège, who was invited to Utrecht to give a colloquium in an effort to find a successor for Uhlenbeck and reported on the work he was then doing with Christian Møller on the meson theory of nuclear forces.