The builders of the world’s biggest particle collider are being sued in federal court over fears that the experiment might destroy the planet. The Large Hadron Collider, or LHC, is due for startup later this year at CERN’s headquarters on the French-Swiss border. It’s expected to tackle some of the deepest questions in science. Some folks outside the scientific mainstream have asked darker questions as well: Could the collider create mini-black holes that last long enough and get big enough to turn into a matter-sucking maelstrom? Could exotic particles known as magnetic monopoles throw atomic nuclei out of whack? Could quarks recombine into “strangelets” that would turn the whole Earth into one big lump of exotic matter?