H is for "h-bar"...
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Orchestrated objective reduction (OOR) is about a wavefunction controlling its own state of quantum superposition vs. reduction.This implementation has to do with Penrose physics, that is with the idea that wavefunction reduction takes place automatically, or "objectively", when a quantum superposition reaches a stage where a crital amount of energy /spacetime difference separates the elements of the superposition.
Taking this idea as given, Hameroff and Penrose assume that a network of microtubules can tune itself appropriately to achieve control of its own state of superposition and reduction. This is known as Orchestrated Objective Reduction. Only a system with sufficient mass can govern the reduction of its own state (otherwise the system remains superposed or else gets entangled with its environment and is reduced that way).
Based on this mass requirement, Penrose and Hameroff calculate the number of microtubules whose entanglement would generate OOR and, significantly, they find orders of magnitude which are consistent with terrestrial biology. There is a paper about this available at Stuart Hameroff's web site. Here is an excerpt from a letter SH posted in March 1995 about OOR:
Penrose Physics, Microtubules & Consciousnesspsyche-d / March 15, 1995
According to the arguments for OR put forth in Penrose (1994),
superposed states each have their own space-time geometries (see
Shadows of the Mind, p. 338). When the degree of coherent mass-energy
difference leads to sufficient separation of space-time geometry, the
system must choose and decay (reduce, collapse) to a single universe
state [avoiding the need for multiple universes as discussed by, for
example, Everett (1957) and Wheeler (1957)]. In this way, a transient
superposition of slightly differing space-time geometries persists
until an abrupt quantum to classical reduction occurs. If as various
philosophers claim (cf. Chalmers, 1994; 1996) the nature of conscious
experience is somehow embedded in the nature of reality,
self-selections in fundamental space-time geometry may address the
"hard problem" of consciousness.
Unlike the random, "subjective reduction" (SR, or R) of standard
quantum theory caused by observation or environmental entanglement, the
OR we propose in microtubules is a self-collapse and it results in
particular patterns of microtubule-tubulin conformational ("eigen-")
states that regulate neuronal activities including synaptic functions.
Possibilities and probabilities for post-reduction tubulin states are
influenced by factors including attachments of microtubule-associated
proteins (MAPs) acting as "nodes" which tune and "orchestrate" the
quantum oscillations. We thus term the particular self-tuning OR
process in microtubules "orchestrated objective reduction" ("Orch OR"),
and calculate an estimate for the number of tubulins (and neurons)
whose coherence for relevant time periods (e.g. 500 milliseconds) will
elicit Orch OR.
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Microtubules
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