This video explains what scientists mean by the observable universe, how far it extends, and why there are limits to what we ...

Since conventional explanations have failed to pony up dark matter, one physicist is looking towards the unconventional. In a series of two papers, physicist Stefano Profumo of the University of ...

Physicists have started to treat a once-fringe idea with surprising seriousness: that our entire observable universe might be the interior of a black hole that formed in some larger cosmos. The notion ...