Henry Stapp is well known for his complex theoretical discourses on the nature of the mind and brain. A distinguished quantum physicist at Lawrence Berkeley National Laboratory, Stapp has been exploring these topics for over 50 years.
Stapp works to establish the case that a causal gap within quantum theory makes it an open system into which free choice can enter. He draws heavily on theories involving “the interplay between the psychologically and physically described components of mind-brain dynamics, as it is understood within the orthodox (von Neumann-Heisenberg) quantum framework”. Stapp draws on and extends von Neumann’s process 1 and 2 theories, adding a process 0 to represent the process which determines the free choice on the part of the experimenter, noting:
"It is the absence from orthodox quantum theory of any description on the workings of process zero that constitutes the causal gap in contemporary orthodox physical theory. It is this ‘latitude’ offered by the quantum formalism, in connection with the freedom of experimentation, that blocks the causal closure of the physical."
Stapp also adds a process 3 to represent the process that selects the probing action. Taken together, processes 0-3 represent the major components of how Stapp views the practical, empirical ontology of quantum theory.
Stapp sets out to transform the brain from a classical to a quantum system. He chooses to attack this by striking at the lowest level of physiological brain function. Drawing on a brief background discussion of cloudlike forms, harmonic oscillation, and the double-slit experiment to introduce the necessity of the brain’s nerve terminals and calcium ion channels being quantum in nature, Stapp argues that because these foundational components are best understood in quantum terms the brain itself must be treated as a quantum system.
Stapp introduces his action template theory involving microscopic brain states capable of producing particular actions if held for a sufficient length of time. He links such actions to von Neumann’s process 1:
"Whether or not the ‘Yes’ component is actualized is determined by ‘nature’ on the basis of a statistical law. So the effectiveness of the ‘free choice’ of this process 1 in achieving the desired end would generally be quite limited. The net effect of this ‘free choice’ would tend to be nullified by the randomness in nature’s choice between ‘Yes’ and its negation ‘No’."
His own theory addresses this problem by drawing on the quantum Zeno effect. One feature of the dynamical rules of quantum theory allows for a stabilization of sorts regarding actions if a string of process 1 events can occur in rapid succession. Essentially if the initial process 1 request is selected by the outcome of the quantum event this action can be held in place by a rapid number of additional similar requests. Stapp believes that this rapid series of additional requests requires mental effort. Here he reaches back to find a kindred spirit in William James.
Stapp reviews recent developments in neuropsychology that support his view. For example, he notes that empirical evidence seems to suggest that conscious effort is correlated with brain activity. According to quantum mechanics, the microscopic uncertainties must rationally be expected to produce macroscopic variations that need to be cut back by quantum reductions.
Consistent with his Jamesian view of cognition, Stapp argues for the quantum brain as a “collection of classically conceived alternative possible states of the brain” all existing as parallel parts of “a potentiality for future additions to a stream of consciousness”.
Overall, this book is a rigorous and demanding reflection drawn from a lifetime of thought by one of the leading theoretical physicists of our day.
By Allan Combs and Jeffery Martin SCR, June 24, 2007 (Allan Combs and Jeffery Martin work at the California Institute of Integral Studies)...Continua