Niels Bohr was born in 1885. The late nineteenth
century was an exciting time for physicists. Bohr entered just
late enough that some of the foundations were beginning to be laid,
but early enough that he could take on a pivotal role in the revolution.
On the one hand, his work built largely on the quantum theories
of Albert Einstein and Max Planck. His own atomic model was a basic
extension of that of his mentor, Ernest Rutherford. On the other
hand, the questions were far from answered, and Bohr's work merely
led to more difficulties to be resolved.
Following his atomic model came rapid developments from other
young scientists. For this new generation of physicists, Bohr would
serve as a mentor. He was the founder and head of the Copenhagen
institute, which would soon become the international center for
modern physics. Young minds came to Copenhagen for cultivation;
established geniuses came to lecture and to take part in colloquia
that often provided the backdrop for conversations that changed
the course of history. Those who visited Copenhagen included Pauli,
Heisenberg, and Schrödinger, all of whom made discoveries that
shattered conventional physics and shocked even those who had tried
to keep up with its rapidly developing pace. Many of these young
scientists came to Bohr for guidance, evaluation, and criticism.
Bohr served not only as an individual mentor, but a symbolic leader
of the physics community at large.
Bohr lived in Denmark, and it was not long before Nazi
Germany influenced his life. Denmark was officially neutral, but
Bohr recognized the necessity of offering refuge to people fleeing
Nazi terror. Copenhagen became a haven for scientists who could
not work in their home countries. Bohr also spoke out more against
the Nazis (though cautiously, since Denmark was officially a neutral
country), proposing a scientific argument for cultural acceptance. Despite
the urging of American colleagues, Bohr refused to leave Denmark
until the last possible moment. After Denmark had been captured
by the Nazis, Bohr stayed because he knew that his departure could
damage the spirit of his country. It was only when he had been
informed that the Nazis were coming for his arrest that Bohr made
a last-minute escape to Sweden by fishing boat. Even then, he continued
to support the Danish resistance and aided in the rescue of thousands
of Jews when it was announced that the Nazis would begin to round
them up in Denmark.
At this time also came the dilemma of atomic energy, which
had become possible largely through the work of Bohr and his close
colleagues. On the one hand, there was enormous potential for beneficial
use, but Bohr from the beginning recognized that its destructive potential
could also lead to diplomatic problems. Even while the war was
still going on, Bohr tried to persuade leaders to consider ways
to avoid an arms race. He urged international cooperation, knowing
that the edge held by Britain and the United States could not last
long. But his warnings were ignored, and the arms race unfolded
exactly as he had feared.
After the war, Bohr returned to Denmark. He continued
for the rest of his life to encourage the appropriate use of atomic
energy and attempted to lead the scientific community in taking
the first steps where political action failed.