“Just when I thought I was out, they pull me back in!” With a sly grin that I’d soon come to recognize, Paul Ginsparg quoted Michael Corleone from The Godfather. Ginsparg, a physics professor at Cornell University and a certified MacArthur genius, may have little in common with Al Pacino’s mafia don, but both are united by the feeling that they were denied a graceful exit from what they’ve built.Nearly 35 years ago, Ginsparg created arXiv, a digital repository where researchers could share their...