t'Hooft video talk: Conformal Gravity -- BH complementarity http://pirsa.org/12050061 Conformal Gravity and Black Hole Complementarity Speaker(s): Gerard t'Hooft Date: 11/05/2012 - 4:40 pm Collection: Conformal Nature of the Universe Definitely worth watching at least some if not all of this talk. I'll try to find some published papers that relate to it. If you know of some already please post the links. The slides and presentation are excellent though the audio level is a bit low, so it demands careful listening. Imagine that nature is fundamentally conformal. Things have definite size for us only because that symmetry is broken by our adopting a flat world perspective. But suppose that reality has that basic symmetry. Then he models a black hole and compares two coordinatizations, from two different points of view. A. from the standpoint of Alice outside who never sees anything fall in and only sees Hawk. rad. come out. MH. and as witnessed by the Mad Hatter who falls in and only sees other infalling stuff and never sees anything get out. Then he says in his conformal setup these two views of reality SHARE THE SAME LIGHTCONE structure, the same view of causality. And he calculates that these two very different views of the same reality differ only by a GAUGE TRANSFORMATION. 't Hooft's scheme of a BH seems radical to me in part because there is no singularity, as far as I can tell. I had to stop watching halfway thru the first time. Will look for some relevant papers and get back to it later today. Does anyone who has already watched the talk have comment?