Thursday, December 30, 2010

Stuart Kauffman Blog Series

Stuart Kauffman has been writing some interesting posts at NPR's 13.7 Cosmos and Culture blog.  Kauffman is a biologist, author and "big thinker", and his latest thoughts are about the possible role of quantum mechanical processes in life and mind. He also has some philosophical speculations related to these ideas.

The latest series of posts takes as a launching point recent theoretical and experimental results which show that it is possible for an open quantum system which has decohered into a classical system (for-all-practical-purposes or FAPP) to re-cohere.  Also there are preliminary indications that such behaviour may occur in a biological context (see recent photosynthesis research):  therefore this is new science which might have applications to understanding mind. The philosophical side to this is that he interprets QM to show that there is an ontological status to possibilia or potentialities in addition to concrete actualities; furthermore the border between these two realms might be where the interesting action takes place (the 'Poised Realm'). He speculates that the ability of systems to repeatedly move between quantum and FAPP classical status might lead to "non-algorithmic" processes. If the human brain utilizes these, it might then constitute a "trans-turing system".

Now all this is alot to digest, and the fearless speculation coupled with invented jargon can be off-putting at first. But I like his ideas and I would recommend readers take a look.  Here are the links (Kauffman also interacts quite a bit with commentors, which is nice).

Part One: Beyond Einstein and Schrodinger?
Part Two: The Quantum Mechanics of Closed Quantum Systems
Part Three: The Quantum Mechanics of Open Quantum Systems
Part Four: The 'Poised Realm' is Real
Part Five: The Non-Algorithmic Trans-Turing System
Part Six: We Seem to be Zombies
Part Seven: How Mind can Act Acausally on Brain?

Update [5 January 2011]:   I'll add new links as they come.  In the latest post, Kauffman discusses the interpretation of QM.  He says that after 85 years, we need to bite the bullet on a less economical ontology.  We need to recognize that there are real possibilities as well as real actuals and the quantum measurement event is the actualization process which bridges these two realms.
Part Eight:  A Hypothesis: Res Potentia and Res Extensa Linked By Measurement

Update [29 January 2011]: Why consciousness might be associated with quantum measurement events.
Part Nine: What is Consciousness? A Hypothesis

Update [30 January 2011]: Looking for the neural correlates of consciousness in measurement events at (entangled) synapses.
Part Ten: Standing the Brain on its Head

Update [31 January 2011]: Last in the series for now:
Part Eleven: Can We Have a Responsible Free Will?


Anonymous said...

Perhaps someone can help explain certain statements in Kauffman's series of posts. In part 3, he writes, "Decoherence is a dissipative process, phase information is LOST from the open quantum system to the environment, thus during decohrence, the Schrodinger equation cannot propagate unitarily." In part 4, he says, "During decoherence, the Schrodinger equation does not apply as it does in closed quantum systems where it is time reversible." And in part 7 he states, "It is essential that decoherence is NOT a causal process."

These statements seem misleading, if not incorrect. Consider a closed system composed of an open system and its environment. The Schrödinger equation evolves unitarily and causally, including during decoherence. The phase information is not actually lost - it is only lost FAPP. One can of course choose to divide this system into two subsystems, the open system and its environment, but that imaginative act does not magically produce some new physics.

It seems that Kauffman is attributing new physics to open systems when all that is really happening is that one is ignoring the information loss from the open system to the environment. It's like saying that Newton's law doesn't apply to a falling object in an open system because we've chosen to ignore air resistance due to the interaction of the ball with the environment. It's not suddenly some mysterious phenomenon that doesn't obey causality or Newton's law.

Steve said...

Hi and thanks for the comment. I think you’re right that there’s nothing new in decoherence theory as sketched in those quotes, and the total system-plus-environment evolves unitarily. If there is new physics it is in the idea he also discusses of a system oscillating between entangled and classical (either docohered or post-measurement collapse) status.

boboniboni said...

Steve, your blog is amazing. I like Stuart Kauffman, gonna check this.

Nicolás Díaz said...

Whoa. I did the same thing today, I was following Kauffman posts and put links to each post in my blog. But reading this I see I missed one of them. I still have my doubts about his hypothesis (using quantum entanglement for this is way too risky) but it is a great stuff to read. I'm following you now in Google Reader. Saludos desde Mexico.

Steve said...

Thank you Nicolás. We can't be sure entanglement is involved in the brain, but I think it's a worthy speculation that should be testable some day.