It cost $10 billion and took 16 years, but the Large Hadron Collider finally went into operation yesterday in Switzerland — and the world didn’t end after all. Scientists are hoping to figure out the nature of so-called “dark matter” as well as the Higgs boson — a hypothetical elementary particle that may explain the origin of mass. “We are on this planet and in this universe a short time,” wrote Michael Barnett, a physicist from the Lawrence Berkeley National Laboratory. “The dreams of a lifetime are waiting, and hopefully not much longer.”