Albert Einstein's general theory of relativity is a landmark in our understanding of the universe. It gave rise to the notion of a spacetime continuum against which all physical phenomena play out.

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 ...

Asking what existed before the Big Bang is often dismissed as meaningless, since traditional physics breaks down when pushed ...

The cosmological constant has plagued physicists for more than a century. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. There is a fundamental ...

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 ...

Albert Einstein’s general theory of relativity is a landmark in our understanding of the universe. It gave rise to the notion of a spacetime continuum against which all physical phenomena play out.

At the frontiers of theoretical physics, many of the most popular ideas have one thing in common: they begin from a mathematical framework that seeks to explain more things than our currently ...

The cosmological constant has plagued physicists for more than a century. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. There is a fundamental ...