Monday, March 07, 2005

Hans Bethe

Yesterday marked the passing of Hans Bethe, the last of the great physicists from the Manhattan Project. I had the privilege of seeing Bethe speak twice when I was a graduate student at MIT in the late 1980's. Bethe was in his early eighties at the time and was still sharp as a tack. One talk was on neutrino oscillations and the other was on disarmament policy. Both talks were well thought out and exhibited the clear thinking that marked Bethe's career.

The amazing thing about Bethe was that he remained relevant for much of the twentieth century. Bethe was held in the highest regard by both his peers and the political establishment throughout his life. He was Sommerfeld's graduate student. His Nobel Prize work on energy production in stars was done in 1938. He played an important role in the development of QED and was Richard Feynman's mentor. He was instrumental in pushing for arms limitation treaties and derailing the Star Wars space-based anti-missile defense during the Reagan administration. He and John Bahcall wrote a landmark paper outlining how the solar neutrino problem was finally solved in 1990. He was a true giant among giants.


Anonymous said...

Hans Bethe, Father of Nuclear Astrophysics, Dies at 98

Hans Bethe, who discovered the violent force behind sunlight, helped devise the atom bomb and eventually cried out against the military excesses of the cold war, died late Sunday. He was 98, among the last of the giants who inaugurated the nuclear age.

His death was announced by Cornell University, where he worked and taught for 70 years. A spokesman said he died quietly at home.

Except for the war years at Los Alamos, N.M., Dr. Bethe lived in Ithaca, N.Y., an unpretentious man of uncommon gifts. His students called him Hans and admired his muddy shoes as much as his explaining how certain kinds of stars shine. For number crunching, in lieu of calculators, he relied on a slide rule, its case battered. "For the things I do," he remarked a few years ago, "it's accurate enough."

For nearly eight decades, Dr. Bethe (pronounced BAY-tah) pioneered some of the most esoteric realms of physics and astrophysics, politics and armaments, long advising the federal government and in time emerging as the science community's liberal conscience.

During the war, he led the theoreticians who devised the atom bomb and for decades afterwards fought against many new arms proposals. His wife, Rose, often discussed moral questions with him and, by all accounts, helped him decide what was right and wrong.

Dr. Bethe fled Europe for the United States in the 1930's and quickly became a star of science. As a physicist, he made discoveries in the world of tiny particles described by quantum mechanics and the whorls of time and space envisioned by relativity theory. He did so into his mid-90's, astonishing colleagues with his continuing vigor and insight.

In a 1938 paper, Dr. Bethe explained how stars like the Sun fuse hydrogen into helium, releasing energy and ultimately light. That work helped establish his reputation as the father of nuclear astrophysics, and nearly 30 years later, in 1967, earned him the Nobel Prize in physics. In all, he published more than 300 scientific and technical papers, many of them originally classified secret.

Politically, Dr. Bethe was the liberal counterpoint (and proud of it) to Edward Teller, the physicist and conservative who played a dominant role in developing the hydrogen bomb. That weapon brought to earth a more furious kind of solar fusion, and Dr. Bethe opposed its development as immoral.

For more than half a century, he championed many forms of arms control and nuclear disarmament, becoming a hero of the liberal intelligentsia. His wife called him a dove, Dr. Bethe once told an interviewer, adding his own qualifier: "A tough dove." His gentle manner hid an iron will and mind that had few hesitations about identifying what he saw as error, hypocrisy or danger. "His sense of duty toward society is so deeply ingrained that he isn't even aware of its being a sacrifice," a close colleague, Dr. Victor F. Weisskopf, once remarked....


Anonymous said...

A wonder :)