"Quantum Enigma: Physics Encounters Consciousness"

The main fodder for my recent post on consciousness was a book I just finished (see post title) by Bruce Rosenblum and Fred Kuttner. It is a very easy introduction to some quantum physics ideas including the "enigma" of superposition and the role of consciousness in the collapse of the wavefunction. It deals mostly with the Copenhagen Interpretation but mentions Everett's Many Worlds and several others. It's all non-technical and a pretty easy read.

Something perhaps interesting to Karl (in the unlikely event that he isn't already aware of them) are two quantum theories of consciousness. A very bare-bones outline is given and I don't quite get them but

1) Roger Penrose and Stuart Hameroff: This theory is based on quantum gravity and "proposes a physical proess beyond present quantum theory that rapidly collapses macroscopic superpositions to actualities. ... This process collapses, or 'reduces,' the wavefunction objectively, for everybody, even without an observer. Penrose calls this process 'objective reduction,' abbreviated OR. Penrose and Hammeroff clain that superposition states and long-range coherence might exist within a brain even though it is in physical contact with the environment, and that spontaneous ORs could regulate synaptic/neural functions. Penrose speculates that OR occurs spontaneously whenever two space-time geometries, and therefore gravitational effects, differ significantly. ... Such ORs would constitute 'occaisons of experience.' If entangled with an object external to the observer, the OR would collapse the wavefunction of the observed object, and everything entangled with it."

2) Henry Stapp: This theory "takes off from von Neumann's formulation of the Copenhagen interpretation. Von Neumannm ... showed that in viewing a microscopic object in a superposition state, the entire measurement system---from, say, the Geiger counter, to the human eye looking at it, to the thus entangled synapses inthe observer's brain---must, strictly speaking, be considered part of a grand superposition state. Only a consciousmess, something beyond Schrodinger equation evolution, can collapse a wavefunction. Stapp postulates two realities, a physical and a mental. The physical includes the brain, perhaps in a particular superposition state. The mental reality includes consciousness, thoughts, and, in particular, intentions. The mental can intentionally act on the physical brain to choose a particular superposition state, which then collapses to a particular situation. Consciousness does not itself 'reach out' to the external world in this theory, but this mental choice itself nevertheless determines, in part, the character of the physcial world external to the body. The final random aspect of the choise is then made by Nature."