Why is the expansion of our Universe accelerating? Twenty-five years after its discovery, this phenomenon remains one of the greatest scientific mysteries. Solving it involves testing the fundamental ...

A new solution to Albert Einstein's theory of general relativity suggests hypothetical gravitational stars that look like black holes could be nested within one another. When you purchase through ...

For 90 years, physicists have tried to solve the equations that constitute Albert Einstein’s theory of general relativity — the concept that matter, space and time are intertwined. But some of ...

New impressions A visualization of a curved space–time “sea” from the general-relativity simulations carried out by the authors.(Courtesy: James Mertens) From the Genesis story in the Old Testament to ...