Author: Rossana Ruggeri, Lecturer and ARC DECRA Fellow, The University of Queensland

By looking at light from distant exploding stars called supernovas, in 1998 astronomers discovered the universe isn’t just expanding – its expansion is speeding up. But what’s behind this acceleration? Enter dark energy. It’s one of the most debated and intriguing missing puzzle pieces of modern physics – a mysterious form of energy believed to uniformly permeate all of space. In the current most accepted model of modern cosmology, dark energy is what drives the accelerated expansion of the universe. But what if there’s another explanation that doesn’t involve dark energy? A recent study using data from supernovas hints there…