An artist's impression of a spinning black hole with the event horizon as a smooth sphere. The reality may be more fuzzy. Photograph: Nasa/Reuters

Until today, the understanding I had of black holes was as a spherical “event horizon” with a singularity at the centre. The event horizon is the surface of no return – anything which goes past it can never escape. The singularity is where quantum gravity kicks in, and is very handy for evading the speed-of-light limit in science fiction plots, where it functions as a gateway to a wormhole which can take the protagonists wherever they need to be.

All this changed during a talk by Samir Mathur of Ohio State University just now, here at the Lepton Photon meeting in Mumbai. It’s all to do with entropy.

via Black holes turn into fuzzballs and destroy a thousand sci-fi plots | Jon Butterworth | Science | guardian.co.uk.