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Thank you so much for your reply! Indeed, Max Tegmark is one of my favorites to watch, but in all fairness I must submit Hameroff's rebuttal to Tegmark's debunking:

The debate on decoherence - Biological feasibility of quantum states in the brain

Quantum approaches can explain enigmatic features of consciousness. However quantum coherent states must be isolated or shielded from environmental interactions and thermal noise which cause "decoherence". Critics of quantum approaches to consciousness point out that the "warm, wet and noisy" brain milieu would be particularly unfriendly to delicate quantum coherent states.

In early 1999 physicist Max Tegmark published a widely reported "refutation" of the "Penrose microtubule" model of quantum consciousness. Tegmark calculated decoherence times for microtubule quantum states (10-13 sec) which seem too fast to affect neuronal functions. An editorial in Science by Charles Seife (Cold numbers unmake quantum mind) suggested Tegmarks calculations had dealt a body blow to quantum consciousness.

However Tegmarks paper didnt address the relevant model (i.e. the Penrose-Hameroff Orch OR model) but one of his own making; he only disproved his own theoretical concoction. Physicists Scott Hagan and Jack Tuszynski and I wrote a paper using Tegmark's own decoherence formula, but correcting for stipulations of the Orch OR proposal. Our paper (Quantum computation in brain microtubules: decoherence and biological feasibility) was published in the June 2002 issue of Physical Reviews (the same journal which published Tegmarks paper) and was also selected for inclusion in the June 2002 issue of The Virtual Journal of Quantum Information. Our calculations using the actual Orch OR proposal gave microtubule decoherence times of about 10-2 to 10-1 sec, with significantly longer times possible based on topological quantum error correction effects due to microtubule structural geometry. Thus our calculations theoretically bring microtubule quantum states into a physiological realm. Recent molecular dynamic simulations of microtubules based on crystallographic structural data by Professor Tuszynskis group further support significant quantum communication.

Tegmark has been invited to debate the microtubule decoherence issue at the forthcoming conference Quantum Mind 2003: Consciousness, quantum physics and the brain but has thus far declined to acknowledge the invitation.

Here we include the abstract of our paper responding to Tegmarks decoherence paper, a link to the complete paper in PDF format, and the Science editorial by Charles Seife.

I don't think they've addressed really Tegmark's critical point. And the 'debate' invitation is a sure sign they're off the scientific reservation. The Biophysical society meeting, the APS meeting, etc. - real scientific meetings - don't have debates.

A state with a coherence lifetime of 10^-5 seconds or longer will surely have a spectroscopic signature. In a protein containing system, which therefore will have low symmetry, transitions from that state will be electric dipole allowed, or observable as resonances using a radiofrequency spectrometer. Neutron scattring should also be observed. Experimental demonstration of a coherent, non-nuclear transition with a linewidth of 10^5 Hz or less would be comparatively simple. Have they done the experiment?

I've read the papers, and IMHO this stuff is nonsense. I will consider changing my mind at the point there is an adequate experimental demonstration of such coherence. People who know some quantum mechanics but are naive about condensed matter can come up with all sorts of wonderful and bizarre effects, all of which are actually dissipated by random molecular motion far faster than they appear, unless you cool down to cryogenic temperatures. The last generation of biophysicists had to put up with something called the Davydov soliton, which actually spawned some hundreds of papers. Same general nonsense, different application. These papers

http://www.public.coe.edu/~jcotting/ss-phy.html

put paid to the soliton quite nicely, but I'd proud to say before I ever read it I'd decided the soliton made no physical sense, based on an understanding of the sorts of dynamics proteins molecules in water undergo. Later papers have indicate the soliton might live a little longer; one in Phys. Rev. B last year suggested 100 ps rather than 1 ps; but there has been no serious experimental support that I'm aware of for the soliton. And science is above all experimental.

Let me give you another analogy; perhaps a better one. If you take two guitars which are exactly in tune, brng them close together, and pluck one, the corresponding string on the other will start to vibrate in resonance with the first, and over a time scale of a second the second string will actually sound and the first will become almost silent. That's resonance, and it's similar to what happens in a quantum system. Now, take both guitars, and put them in a room where you fire off a gun every half second; or (more reasonably) blast 100 dB white noise through a stereo speaker. Will the resonance occur? No, because both are exposed to a far more intense random excitation from the noise. They'll both vibrate stochastically in response to the noise, but they'll cease to talk to each other.

Don't take my word for it, do the experiment, and let me know what happens. Make sure the noise is really loud, though; loud enough to make a single guitar string vibrate on its own.

Unless someone posts something unforseen on the subject, this will be my last word on it. I'm happy to sit back and be vindicated by history.