Einstein’s letters illuminate a mind grappling with quantum mechanics
Back in the days before the internet — with no e-mail, no texting, no Twitter — people wrote letters. Even famous people, like Einstein. And famous people’s letters were most likely to have been saved — and in Einstein’s case, published. For more than 30 years now, the Princeton University Press has been publishing Einstein’s letters (and his papers, and talks, and whatever else he wrote). His letters reveal nuances about his genius — and some downsides to his personality — that seldom show in his formal papers and lectures. This month Princeton released the latest volume of Einstein’s papers, covering the period May 1925–June 1927, while Einstein was at the University of Berlin. It was an especially exciting time in science, as it corresponded with the infancy of quantum mechanics, midwifed by Werner Heisenberg in 1925 while at the University of Göttingen in Germany. Einstein also faced new challenges to his theory of...