Philosophy of cosmology

Traditionally, observers play no special role in physics. Like bird watchers in a perfect hide, we observe the outcome of experiments, or gaze at the stars through our telescopes, taking no part in the action. Modern physics, however, tells a different story ... find out more with these articles and videos.

Can the very act of observing something change what's being observed? This series of articles and videos explores some basic questions about the role of the observers in physics.

If there's a multiverse, then how many of its component universes are like our own?

If there's a multiverse, then how many of its component universes are like our own?

What do we know about our Universe? And could there be more than one?

To celebrate the release of more English translations of Einstein's papers, we revisit one of his previously unknown models of the Universe.

If you like to have your mind blown cosmology is a great field to go into. But is it science?

George Ellis explains why the study of the cosmos poses some very deep questions.

Data from BICEP2 gathered in the South Pole reveals swirls in the CMB, the first image of gravitational waves and evidence for inflation.

David Sloan calculates how likely it is that our Universe exists. He explains to us how, and why the answer can help shape our theories of physics.

There's no doubt that maths is very good at describing the world around us. Could this be because the Universe we live in is itself a mathematical structure? We talk to Max Tegmark.