Wasn’t Einstein so irritated at the thought of randomness in the universe that he said, “God does not play dice with the universe”? Your article seemed to suggest that Einstein endorsed quantum physics, which I was under the impression he didn’t.

Andrew Alexander
Toronto, Ont

Einstein did loathe the idea that physical processes could be random. The physicist Niels Bohr, one of quantum physics’ strongest proponents, once retorted the quote you mentioned with, “Einstein, stop telling God what to do!” In 1930, Bohr forced Einstein, through a thought experiment, to accept the uncertainty principle of quantum mechanics. Einstein tried unsuccessfully for the remaining 25 years of his life to show that the world behaves predictably .—E. Klarreich