Scientists have done it again—this time, they’ve taken something as intangible as light and turned it into a state of matter that both stands its ground and flows like a ghost. That’s right, light is now a supersolid, which sounds like something a sci-fi villain would try to harness for world domination. But instead of doomsday lasers, this breakthrough could lead to revolutionary quantum tech. Next up: scientists figuring out how to make a couch that’s comfortable but doesn’t trap your remote.