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 ...

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 ...

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 ...

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 ...

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 ...

Einstein proposed and published his theories of special and general relativity in 1905 and 1915. The concepts are monumental ...

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 ...

For more than a century, physics has been built on two great theories. Einstein's general relativity explains gravity as the ...