Born Hans Albrecht Bethe, July 2, 1906, in Strasbourg, Alsace-Lorraine; died of congestive heart failure, March 6, 2005, in Ithaca, New York. Physicist. Over the course of his more than 60-year career, Nobel laureate Hans Bethe published more than 300 scientific papers, averaging one significant breakthrough a decade. One of the leading theoretical physicists of the 20th century, Bethe is best known for figuring out how stars produce light and in 1967 won the Nobel Prize in Physics for this work. In addition, Bethe played a key role in the development of the atomic bomb that ended World War II, though after its use, he spent the remainder of his life calling for a halt to nuclear proliferation.
An only child, Bethe (pronounced BAY-tuh) was born into a family of academicians on July 2, 1906, in Strasbourg, Alsace-Lorraine, an area France and Germany spent decades fighting over. At the time of Bethe's birth, the city was part of Germany. Bethe's father, a Protestant, was a physiologist at the University of Strasbourg and later taught in Frankfurt. His Jewish mother was also the child of a professor. Because the family was not religious, Bethe never considered himself Jewish.
Early on, Bethe demonstrated great ability in mathematics, though his father tried to squelch his interest because he wanted Bethe to fit in with his peers and not get too far ahead. Bethe, however, swiped his father's trigonometry and calculus books and read them in secret. He studied at the University of Frankfurt, then earned a doctorate from the University of Munich in 1928, graduating summa cum laude.
Bethe first taught physics close to home in Frankfurt and Stuttgart, then ventured out to Cambridge, England, and Rome. In the early 1930s he returned to Germany to teach at Tubingen University only to find his classes filled with swastika-clad students. Within a year he was let go as Adolf Hitler invoked a policy of anti-Semitism throughout the land.
Bethe fled to Britain and later to the United States, where in 1935 he landed at Cornell University in Ithaca, New York, where he spent the remainder of his academic career. Bethe drew attention to himself shortly thereafter by publishing, with the help of various collaborators, three articles on thermo-nuclear reactions in the American Physical Society's Reviews of Modern Physics. At the time, nuclear physics was a new field of study and these papers, which became known as "Bethe's Bible," served as the primary text on the subject for decades.
One of Bethe's most amazing discoveries came after a 1938 astrophysicists conference at the Carnegie Institution in Washington, D.C. There, the question was posed: What makes stars shine? Philosophers and astronomers had sought the answer for centuries. It took Bethe six weeks to end the mystery. Relying on his knowledge of nuclear reactions and fusion, Bethe churned out a stack of pencil and paper calculations and published them in a paper called "Energy Production in Stars." In the paper, Bethe described the process by which the sun, and similar stars, merge hydrogen into helium, thus discharging energy that bursts forth as heat and light.
In 1939 Bethe married Rose Ewald, daughter of German physicist Paul Ewald of Stuttgart, whom Bethe had worked under. Two years later, he became a U.S. citizen and as World War II unfolded, he joined the war effort by working on radar technology at the Massachusetts Institute of Technology. Later, he was appointed chief theoretical physicist of the secret Manhattan Project lab in Los Alamos, New Mexico, which developed the atomic bomb.
At Los Alamos, Bethe directed teams of leading physicists in carrying out the complex calculations necessary to build the bomb. His team figured out how much plutonium would be needed and worked to figure out if such a detonation would ignite the earth's atmosphere and destroy the planet. Team members began calling him "The Battleship" because of the way he destroyed potential problems by steaming right through to an answer.
Though Bethe helped develop the A-bomb, he believed building it was morally wrong; however, he was eager to help defeat Nazism and figured if he did not help the United States develop the A-bomb, Germany would soon enough, making Hitler unstoppable. After the war Bethe returned to academia and became a vocal critic of the nuclear arms race. He helped negotiate the first nuclear test ban treaty, which essentially banned all atmospheric tests. By the 1990s Bethe was calling for a total ban on nuclear tests.
Bethe retired from teaching in 1975 but continued writing professional papers and near the end of his life was studying and writing about the collapse of stars. To the end, he never turned to computers for calculations, relying instead on a slide rule, pencil, and paper. In his free time he enjoyed skiing, mountain climbing, and traveling, especially by train. He continued advising presidents, a service he began in the Harry Truman administration and carried on through President Bill Clinton.
Most of all, Bethe was known for inspiring generations of Cornell physicists. Speaking to the Los Angeles Times, the late MIT physicist Philip Morrison, who worked at Los Alamos with Bethe, once said, "Of all the people who are so bright and accomplished, few are so sweet of temperament. He finds errors in such a way as you're pleased to have the help."
Bethe died of congestive heart failure on March 6, 2005, at his home in Ithaca, New York. He was 98. He is survived by his wife, Rose; his son, Henry; his daughter, Monica; and three grandchildren. Sources: Independent (London), March 9, 2005, p. 34; Los Angeles Times, March 8, 2005, p. A1, p. A22; New York Times, March 8, 2005, p. A1; Washington Post, March 8, 2005, p. B6.
— Lisa Frick