NUCLEAR PHYSICS The nuclear age dawned in the wrong
place, at the wrong time. In 1938, outside Berlin's Kaiser Wilhelm
Institute for Chemistry, Nazis paraded in the streets. Inside, German
Chemist Otto Hahn patiently probed the secrets of the atom. He repeated
an experiment that had been tried by half a dozen researchers,
including Enrico Fermi in Rome and Irene Joliot-Curie in Paris. With his primitive equipment, he repeatedly bombarded the element
uranium with neutrons in an effort to create new man-made radioactive
isotopes. According to the theories of the time, the neutrons should
have combined with the nucleus of the uranium atoms to produce heavier,
unstable isotopes. Yet he kept finding lighter atoms of barium.
Gradually, the inexplicable presence of the barium, which is only about
half the weight of uranium, persuaded Hahn that he had done what had always
been considered impossible: he had split the atom. Hahn's innate caution stopped him from making so bold a claim in public.
“As nuclear chemists,” Hahn and his young collaborator, Fritz
Strassmann, wrote later, “we cannot bring ourselves to take this step,
so contradictory to all the experience of nuclear physics.” But Hahn's
former coworker, Physicist Lise Meitner, had no such hesitation.
Hearing of the experiment in exile in Sweden, she not only proclaimed
that Hahn and Strassmann had achieved nuclear fission, but also
calculated that each atom of uranium had released 20 million times as
much energy as a comparable amount of TNT. Fission's frightening potential quickly became apparent to scientists
everywhere. But Hitler considered the new theoretical physics too
contaminated by Jews like Lise to be worthy of much support. Although
not a Jew himself, Hahn was no friend of the regime. Throughout World
War II, he was left undisturbed at his work, exploring radioactive
isotopes. In the U.S., where scientists assumed that the Germans were
following up his atom-splitting success, the race was on to achieve
fission on a more Promethean scale. In 1945, after Germany's defeat,
the results were displayed at Hiroshima. Shattered Remains. One of many German scientists interned by the Allies,
Hahn heard the news of the atomic bomb in England. Normally a man of
dry, underplayed wit, he became so depressed by the appalling
application of fission that his colleagues feared that he might commit
suicide. Once back in Germany, Hahn struggled to rebuild the shattered
remains of his old institute as president of its successor, the Max
Planck Society. He also became an outspoken foe of atomic weapons. In
1957, joining the 17 other prominent West German scientists in the
Gttingen Manifesto, he vowed never to take part in nuclear research
for military purposes.
