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 ...

Access more than 20 years of online content Manage which e-mail newsletters you want to receive Read about the big breakthroughs and innovations across 13 scientific topics Explore the key issues and ...

The Einstein equations remain the cornerstone of general relativity, underpinning our understanding of how matter and energy influence spacetime curvature. Recent investigations have not only ...

When two massive black holes slammed into each other earlier this year, astronomers were able to observe it in the clearest ...

A newly developed solution to the equations at the heart of Albert Einstein's most revolutionary theory suggests hypothetical stars called "nestars" could be made from stacked gravitational stars, or ...

This equation of special relativity describes time dilation. Mathematical equations aren't just useful — many are quite beautiful. And many scientists admit they are often fond of particular formulas ...

Black holes are so strange that physicists have long wondered if they are quite what they seem. Now we are set to find out if ...

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. At least 3,700 years ago, Babylonian mathematicians approximated the ratio of a circle's ...