Sitzfleisch

Freeman Dyson reviews the new biography of Oppenheimer by Ray Monk. I discussed the book already here.

NYBooks: ... The subtitle, “A Life Inside the Center,” calls attention to a rarer skill in which Oppenheimer excelled. He had a unique ability to put himself at the places and times at which important things were happening. Four times in his life, he was at the center of important events. In 1926 he was at Göttingen, where his teacher Max Born was one of the leaders of the quantum revolution that transformed our view of the subatomic world. In 1929 he was at Berkeley, where his friend Ernest Lawrence was building the first cyclotron, and with Lawrence he created in Berkeley an American school of sub-atomic physics that took the leadership away from Europe. In 1943 he was at Los Alamos building the first nuclear weapons. In 1947 he was in Washington as chairman of the General Advisory Committee of the United States Atomic Energy Commission, giving advice to political and military leaders at the highest levels of government. He was driven by an irresistible ambition to play a leading part in historic events. In each case, when he was present at the center of action, he rose to the occasion and took charge of the situation with unexpected competence.

... In 1939 Oppenheimer published with his student Hartland Snyder a paper, “On Continued Gravitational Contraction,” only four pages long, which is in my opinion Oppenheimer’s one and only revolutionary contribution to science. In that paper, Oppenheimer and Snyder invented the concept of black holes; they proved that every star significantly more massive than the sun must end its life as a black hole, and deduced that black holes must exist as real objects in the sky around us. They showed that Einstein’s theory of general relativity compels any massive star that has exhausted its supply of nuclear fuel to enter a state of permanent free fall. Permanent free fall was a new idea, counterintuitive and profoundly important. It allows a massive star to keep falling permanently into a black hole without ever reaching the bottom.

Einstein never imagined and never accepted this consequence of his theory. Oppenheimer imagined it and accepted it. As a direct result of Oppenheimer’s work, we now know that black holes have played and are playing a decisive part in the evolution of the universe. That is the historical fact. The mystery is Oppenheimer’s failure to grasp the importance of his own discovery. He lived for twenty-seven years after the discovery, never spoke about it, and never came back to work on it. Several times, I asked him why he did not come back to it. He never answered my question, but always changed the conversation to some other subject.

It is true, as Monk demonstrates, that Oppenheimer’s ruling passion was to be a leader in pure science. He considered his excursions into bomb-making and nuclear politics to be temporary interruptions. My interactions with Oppenheimer confirm Monk’s picture of him. I worked at the Institute for Advanced Study for almost twenty years while Oppenheimer was director. He rarely talked about politics and almost never about bombs, but talked incessantly about the latest discoveries and puzzles in pure science.

... Oppenheimer continued for the rest of his life to be proud of his achievement at Los Alamos. ... Monk expresses his opinion, with which I agree, that Oppenheimer’s anger arose from his deep loyalty to America. For him, expressing regret for what he had done for his country would have meant joining his country’s enemies.

... Oppenheimer was above all a good soldier. That is why he worked so well with General Groves, and that is why Groves trusted him. I have a vivid memory of the ice-cold February day in 1967 when we held a memorial service for Oppenheimer at Princeton. Because of the extreme cold, attendance at the service was sparse. But General Groves, old and frail, came all the way from his home to pay his respects to his friend. ...

The real tragedy of Oppenheimer’s life was not the loss of his security clearance but his failure to be a great scientist. For forty years he put his heart and soul into thinking about deep scientific problems. With the single exception of the collapse of massive stars at the end of their lives, he did not solve any of these problems. Why did he not succeed in scientific research as brilliantly as he succeeded in soldiering and administration? I believe the main reason why he failed was a lack of Sitzfleisch. Sitzfleisch is a German word with no equivalent in English. The literal translation is “Sitflesh.” It means the ability to sit still and work quietly. He could never sit still long enough to do a difficult calculation. His calculations were always done hastily and often full of mistakes. In a letter to my parents quoted by Monk, I described Oppenheimer as I saw him in seminars:

He is moving around nervously all the time, never stops smoking, and I believe that his impatience is largely beyond his control.

In addition to his restlessness, Oppenheimer had another quality, emphasized by Monk in the subtitle of his book. He always wanted to be at the center. This quality is good for soldiers and politicians but bad for original thinkers. ...

I have to admit that my own Sitzfleisch, while well above average for a normal person, is probably less than required for true excellence in theoretical physics.