Abraham Pais

Abraham Pais bigraphy, stories - American  Physicist

Abraham Pais : biography

May 19, 1918 – July 28, 2000

Abraham Pais (May 19, 1918 – July 28, 2000) was a Dutch-born 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 Jews who migrated 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 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 an elementary schoolmaster, headmaster, and later the headmaster of the Sephardic 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 higher burgher school 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.

Career in particle physics

During World War II, Pais’s doctoral dissertation had attracted the attention of Niels Bohr, who invited him to come to Denmark as his assistant. Pais was forced into hiding before he could leave the Netherlands. In 1946, following the war, Pais was able to accept that invitation and served as a personal assistant to Bohr at his country home in Tisvilde for a year.

In 1947 he accepted a position at the Institute for Advanced Study in the United States and thus became a colleague of Albert Einstein.

For the next 25 years he worked on elementary particle theory with a primary interest in quantum field theory and symmetry. The technical contributions for which he is recognized include a precise definition of G-parity with Res Jost, and his treatment of SU(6) symmetry breaking.

He is primarily associated with two concepts that directly contributed to major breakthroughs in his field. The first was the idea of "associated production" to explain the puzzling properties of strange particles. His ideas and those of Murray Gell-Mann resulted in the idea of a quantum number called strangeness. The second concept was Pais’s and Gell-Mann’s theory regarding the composition of the neutral kaons, proposing that the observed states were admixtures of particles and antiparticles, having different lifetimes; this was experimentally confirmed in the following year by Lederman and collaborators. In 1956, Pais became a naturalized citizen of the United States.

In 1963 Pais accepted a position at Rockefeller University to head the theoretical physics group while Rockefeller was in transition from being a medical institute to a university. He finished his career there as the Detlev W. Bronk professor emeritus.

Later life

After his retirement Pais and his third wife Ida Nicolaisen spent half their time in Denmark where he worked at the Niels Bohr Institute.

His son Josh Pais is an American actor.

Pais died of heart failure in Copenhagen.


Science historian

In the late 1970s Pais became interested in documenting the history of modern physics. He felt he was in a unique position to do so, having known many of the key people and with his knowledge of the language, culture, and science.