The caustic mathematician Roger Casals Gutiérrez saw on his kitchen wall in 2023. Caustics are a type of singularity, a mathematical phenomenon that occurs when an surface goes through a transition.
Can we do away with the troublesome singularity at the heart of black holes? A new paper in JCAP reimagines these extreme objects in light of current knowledge. “Hic sunt leones,” remarks Stefano ...