Our universe might be really, really big — but finite. Or it might be infinitely big. Both cases, says physicist Brian Greene, are possibilities, but if the latter is true, so is another posit: There ...

Hints of a mirror cosmos have a way of gripping the imagination, and recent chatter about “first proof” of a parallel universe has pushed that fascination back into the spotlight. Behind the viral ...

Over the last few years, the box office has been dominated by films like "Spider-Man: Across the Spider-Verse" that explore ideas of parallel universes, quantum worlds and alternate lives. There's ...

Chinese researchers are poring over a puzzling gravitational wave signal that appears to defy the standard script of black hole collisions, reviving one of physics’ most audacious possibilities: that ...