But his work in this period made very little impact on contemporaries and he never found his grand theory – something physicists are still grappling with.
The archive was collected by Einstein’s colleague Ernst Gabor Straus, a young mathematician whom the great physicist selected to help him during his Princeton years. “A lot of people think of Einstein as a mathematical genius – he wasn’t,” said David McMullan, a physicist at Plymouth University. He said Einstein used Straus as he had used other mathematically gifted colleagues in his early career. “Straus’s mathematical virtuosity gave a framework to Einstein’s intuitive vision of the universe.”
He said it was fascinating to see breakthroughs not coming easily to Einstein. “I do think it is interesting, the way you see him groping around. He’s just trying anything. Here we see the greatest scientist who ever lived struggling and being honest about it.”
In one sequence of 16 letters Straus criticises a line of inquiry that Einstein is pursuing and eventually persuades him to abandon it. “It would take somebody with real balls to say to Einstein, ‘look, this is wrong’,” said Peter Coles, a physicist at Nottingham University.
The papers have never been studied because they have been held by Straus and his family since they were written. Einstein scholars were not even aware they existed until Straus’s wife and son decided to put them on the market. They tell the story of the two men’s evolving thought process in the vain search for the unified field theory, as the grand theory was called.