Physicists are quietly testing wild new theories that treat a hidden fifth dimension as more than science fiction, suggesting ...

Physicists are increasingly entertaining a radical possibility: our familiar universe of three dimensions of space and one of time might be only part of a larger structure, with a hidden fifth ...

The Standard Model of our universe doesn’t match the evidence, in part because of dark energy, a ghostly force pushing the universe apart. Now some researchers think our universe might be moving into ...