What if there are other universes, just like ours? With an infinite number of Earths? With uncountable versions of you? And ...

Physicists are quietly entertaining one of the strangest ideas in modern cosmology: that the cosmos we see might be only half ...

We have not been able to detect dark matter yet, even though there are many aspects of the universe that suggest the existence of invisible matter. In one new theory, it is possible that dark matter ...

Scientists estimate that 95 percent of the matter in the universe is dark. Not strictly the domain of “billions and billions of galaxies,” as Carl Sagan was fond of saying, the universe is composed of ...

A new theory claims dark matter and dark energy don’t exist — they’re just side effects of the universe’s changing forces. By rethinking gravity and cosmic timelines, it could rewrite our ...

Dark energy, a mysterious force that scientists believe is behind the accelerated expansion of the universe, is weakening — which could result in the universe over the course of billions of years ...

Searches for dark matter particles have come up empty so far, driving theorists to get more creative with their ideas. Smooth filaments stretching for many light-years, seen by the powerful space ...