SpaceWhy the big bang may not have been the beginning of the universeWe once thought the big bang was a single moment, but physicists are now settling on a different version of events, writes Chanda Prescod-WeinsteinComment
SpaceEverything we know about the universe – and a few things we don'tHow big is the universe? What shape is it? How fast is it expanding? And when will it end? We answer these questions and more in our essential guide to the current state of cosmological knowledgeFeatures