---
title: "J. Robert Oppenheimer"
chunk: 9/17
source: "https://en.wikipedia.org/wiki/J._Robert_Oppenheimer"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:07:13.473219+00:00"
instance: "kb-cron"
---

== Postwar activities ==
Once the public learned of the Manhattan Project after the bombings of Hiroshima and Nagasaki, Oppenheimer—suddenly a household name as the "father of the atomic bomb"—became a national spokesman for science, emblematic of a new type of technocratic power; he appeared on the covers of Life and Time. Nuclear physics became a powerful force as nations realized the strategic and political power that atomic weapons conferred. Like many scientists of his generation, Oppenheimer felt that security from atomic bombs could come only from a transnational organization such as the newly formed United Nations, which could institute a program to stifle a nuclear arms race.

=== Institute for Advanced Study ===

In November 1945, Oppenheimer left Los Alamos to return to Caltech, but soon found that his heart was no longer in teaching. In 1947, he accepted an offer from Lewis Strauss to take up the directorship of the Institute for Advanced Study in Princeton, New Jersey. This meant moving back east and leaving Ruth Tolman, the wife of his friend Richard Tolman, with whom he had begun an affair after leaving Los Alamos. The job came with a salary of $20,000 per annum, plus rent-free accommodation in the director's house, a 17th-century manor with a cook and groundskeeper, surrounded by 265 acres (107 ha) of woodlands. He collected European furniture, and French Post-Impressionist and Fauvist artworks. His art collection included works by Cézanne, Derain, Despiau, de Vlaminck, Picasso, Rembrandt, Renoir, Van Gogh and Vuillard.
Oppenheimer brought together intellectuals at the height of their powers and from a variety of disciplines to answer the most pertinent questions of the age. He directed and encouraged the research of many well-known scientists, including Freeman Dyson, and the duo of Chen Ning Yang and Tsung-Dao Lee, who won a Nobel Prize for their discovery of parity non-conservation. He also instituted temporary memberships for scholars from the humanities, such as T. S. Eliot and George F. Kennan. Some of these activities were resented by a few members of the mathematics faculty, who wanted the institute to stay a bastion of pure scientific research. Abraham Pais said that Oppenheimer himself thought that one of his failures at the institute was being unable to bring together scholars from the natural sciences and the humanities.
During a series of conferences in New York—the Shelter Island Conference in 1947, the Pocono Conference in 1948, and the Oldstone Conference in 1949—physicists transitioned from war work back to theoretical issues. Under Oppenheimer's direction, physicists tackled the greatest outstanding problem of the pre-war years: infinite, divergent, and seemingly nonsensical expressions in the quantum electrodynamics of elementary particles. Julian Schwinger, Richard Feynman and Shin'ichiro Tomonaga tackled the problem of regularization, and developed techniques that became known as renormalization. Freeman Dyson was able to prove that their procedures gave similar results. The problem of meson absorption and Hideki Yukawa's theory of mesons as the carrier particles of the strong nuclear force were also tackled. Probing questions from Oppenheimer prompted Robert Marshak's innovative two-meson hypothesis: that there are actually two types of mesons, pions and muons. This led to Cecil Frank Powell's breakthrough and subsequent Nobel Prize for the discovery of the pion.
Oppenheimer served as director of the institute until 1966, when he gave up the position due to his failing health. As of 2023, he is the longest-serving director of the institute.

=== Atomic Energy Commission ===