Who: Gerardus 't Hooft, Institute for Theoretical Physics, Utrecht, The Netherlands
Place: Donostia International Physics Center
Date: Wednesday, 3 October 2018, 12:00
Since Hawking's discovery that quantum field theoretical features force black holes to emit articles at a calculable rate, some researchers realised that some modifications in the laws of General Relativity in its relation to Quantum Mechanics may be called for. This is of crucial importance for a better understanding of Quantum Gravity. It is often claimed that (super)string theory, adorned with AdS/CFT conjectures, should provide for all the answers, but we claim that this is not so. These theories are not sufficiently precise to notice violations of unitarity and causality, caused by subtle quantum singularities such as "firewalls" along the event horizon, if one is not sufficiently careful in choosing boundary conditions at this horizon. But one can do the calculations without string theory or AdS/CFT, and then some remarkable results arise, leading to predictions that might become experimentally observable when horizons can be inspected with telescopes.