Hans Bethe

Nobel -Prize-winning physicist Hans Bethe died last Saturday in Ithaca, New York. He was 98 years old.

I remember Bethe from his time as a visiting scholar at Caltech when I was a physics graduate in the mid-1980s. My impression of him was that of a kind-hearted and gentle man. When he smiled, which was often, he looked like the demented subject of a Brughels painting or Doré engraving; but both his sharp mind and warm heart showed through.

Bethe received his doctorate in 1928, in the heyday of the quantum revolution, when giants walked the laboratories and classrooms of Europe. He was one of the pioneers of nuclear physics, and his work in the '30s on the C-N-O cycle of nuclear reactions that fuels the sun eventually won him his Nobel Prize in 1967. When the Nazis took power in Germany he fled to the United States. He was one of J. Robert Oppenheimer's early recruits to the Manhattan Project, and he headed the Theory Division at Los Alamos.

After the war and the Manhattan Project, Bethe returned to his post at Cornell University, attracting such lights of the next generation as Richard Feynman and Freeman Dyson to work with him. In the nuclear politics of the time, he positioned himself as the Anti-Teller, lobbying against the development of the H-bomb (although he in fact did some work for that project), and for nuclear disarmament and for banning of nuclear testing.

And in the 1980s, when Edward Teller was spinning fantasies that the gullible Ronald Reagan turned into policy in the form of the Strategic Defense Initiative, Bethe spoke out against Star Wars. It was at this time that Bethe revealed to the public that behind Teller's betrayal of Oppenheimer was Teller's desperate search for a fall-guy when the H-bomb project at that point was fruitless and the government wanted to know why.

I remember a talk at Caltech by Teller's protege Lowell Wood – the most evil human being it has yet been my misfortune to encounter in the flesh – in which Wood was pitching the Livermore Lab's nuclear-explosion-pumped X-ray laser program to an uncharacteristically stone-faced Hans Bethe. I walked out of that lecture hall feeling like Peter Venkman after his first encounter with a ghost. Seing the grim countenance on the face of the usually smiling and happy Bethe made me imagine that he felt something similar. (The X-ray laser never worked, and, true to form, Teller and Wood wrecked another career of another fall-guy.) According to the Times obituary for Bethe, "In his memoirs in 2001, Dr. Teller accused Dr. Bethe of letting his political views color his technical judgment." Perhaps a wee bit of projection was going on here.

Hans Bethe has always been in my mind a shining example of a person who brought his conscience and moral judgment to his work as a scientist, and as a person who named the truth in the face of evil. His long and fruitful life is now over, and he lives on in the hearts of those whom he has inspired.