sure. but there are very tangible bounds on the sorts of physical interactions that can cause any effect. for instance, lots of people love the idea of "brain

sure. but there are very tangible bounds on the sorts of physical interactions that can cause any effect. for instance, lots of people love the idea of "brain waves". in general, neurons are event-driven, not given to "waving". indeed, the mystique of brainwaves is counter-physical, in that when there is synchronized activity, it produces EM signals that are fairly hard to pick up (EEG, MEG have gains O(1e6)). a neuron simply lacks a physical mechanism to be affected by such a wave. not unlike Tegmark pointing out that the brain is dense and warm and that means short/fast decoherence.