Roger Penrose, Mathematical Institute, Oxford University
It is a widespread view that not only can all the actions of a human brain be simulated by appropriate computation, but that it will not be too far into the future before computers become so powerful that they will be able to exceed the mental capabilities of any human being. I argue, however, by using examples from chess and mathematics, that the quality of conscious understanding is something distinct from computation. I maintain, nevertheless, that the action of a conscious brain is the product of physical laws, whence consciousness itself must result from physical processes of some kind. Yet physical actions, over a huge range, can be simulated very precisely by computational techniques. This is exemplified by the LIGO gravitational wave detectors confirming precise calculations within Einstein’s general relativity theory, of signals from black-hole encounters in distant galaxies.
Despite this, I argue that there is a profound gap in our understanding of how Einstein’s theory affects quantum systems, and that there is reason to believe that the process termed “collapse of the wave-function” takes place objectively (gravitational OR), in a way that defies computational simulation. It is argued that each such event is accompanied by a moment of “proto-consciousness”, and that actual consciousness is the result of vast numbers of such events, orchestrated in an appropriate way so as to provide an actual conscious experience (Orch-OR).
Experiments to test the OR hypothesis, involving Bose-Einstein condensates, as put forward by Ivette Fuentes and her group in Nottingham UK, will be briefly described.