Einstein's equations might need a rewrite — that is, if we want to explain how the insides of black holes work. Einstein's theory of general relativity describes the relationship between space-time and matter. It successfully explains the structure of neutron stars, the formation of black holes and the evolution of our universe. But there is one problem — general relativity predicts a singularity, or a point of infinite density at the heart of a black hole where space-time and matter are crushed and stretched into non-existence. A space where nothing exists but that everything falls toward: a paradox. However, by...