Whether or not they succeed in remaking space and time, twistorians and string theorists have already endeared themselves to particle physicists. Even fairly simple particle collisions demand equations containing tens of thousands of terms, which are written using a strategy devised by the famous physicist Richard Feynman in the 1940s. Almost all of those terms end up canceling out, but you don’t know in advance which will cancel, so you have to slog through all of them. An alternative strategy inspired by twistors and strings captures symmetries that Feynman’s approach does not, so it sheds the excess mathematical baggage from the outset. Calculations that math whizzes once gave up on now take just a couple of weeks. “I’m pretty sure Feynman would be quite pleased if he saw what we can do,” says Zvi Bern of the University of California, Los Angeles.
The emerging theory of spacetime is still very tentative and so mathematically dense that even those physicists directly involved admit they can barely follow what is going on. Theorists have yet to explain why, if spacetime is merely a construct, it nonetheless seems so real to us. It must somehow take shape much as life springs from inanimate matter. Whatever the process is, it cannot occur only on subatomic scales, because the concept of size must itself emerge. It should be evident on all scales, everywhere around us, if only we know how to look.