Niels Bohr’s Times

Abstract

Abstract The life of Niels Bohr spans times of revolutionary change in science itself as well as in its impact on society. As the curtain rises, the reality of atoms is still under debate, the structure of atoms still a matter of conjecture, the atomic nucleus is not yet discovered, practical applications of atomic energy, for good or evil, are not even visible on the far horizon. All that changed during Bohr’s life, much of it under his own influence. He was the first to understand how atoms are put together, he played a leading role in the development of the theory of the atomic nucleus, and he was the godfather of nuclear medicine. He was also th first to bring to the attention of leading statesmen the need for openness betwe1:m West and East, a need resulting from the advent of formidable new weapdms developed during and after World War II. Time and again he would stress that openness was essential for political world stability.Even more profound than new discoveries and perceptions regarding the structure of matter are new physical laws discovered in that same period. Here the key concepts are relativity theory and quantum theory. Bohr was the principal figure in elucidating the revisions of the philosophical foundations of physics needed for a comprehension of quantum phenomena. I have been told that Vladimir Horowitz once commented on Mozart’s music that it is too easy for beginners and too hard for experts. The same can be said of quantum physics. In this book I attempt to outline for beginners how most experts think about quantum theory.