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Quantum Mechanics Involved In Photosynthesis
Kristina at Science News writes "We all learn about photosynthesis in school: sunlight in, plant food out. Not well understood is how this process achieves its initial and uniquely high efficiency in capturing the energy of a photon. Quantum mechanics may be at work in the electron transfer process inside chloroplast, giving electrons the chance to consider many paths at once before choosing the best one."
Science has now discovered that one of the more universal concepts in physics applies to... just about everything above the subatomic scale!
News at 11.
It's covered in physics, to the extent that photosynthesis and the photoelectric effect are used to demonstrate photons must have momentum. (The law of conservation of momentum requires that the momentum going in equals the momentum coming out, so if the electron has momentum, then the photon must also.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Sure, but QM is still a framework for describing everything that exists. That doesn't mean it's a complete framework, even though it's largely complete, and more complete all the time.
Photosynthesis is fully described by QED. That doesn't mean that photosynthesis "uses QM", any more than it "used phlogistons" if it were described analytically in the early 1800s. Or rather, photosynthesis "uses" QM, or phlogistics, or whatever other framework is being used to describe photosynthesis more or less accurately.
The point is that QM is not a process, like "electron cascade", that photosynthesis "uses". It's a framework within which to describe processes like electron cascades that photosynthesis uses.
If we were describing photosynthesis solely in terms of gravitational phenomena, then it might be remarkable to say that our explanation uses QM to describe what happens, because QM doesn't accurately describe gravitation. But that's not what we've got in this case.
Besides, the QM of photosynthesis has been described for quite a while. A new wrinkle in it does not merit a headline announcing that QM is involved.
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make install -not war
Quantum computers are Turing reducible. It doesn't matter if your computer is classical or quantum, they can still only solve the same kinds of problems. This goes for the brain as well. (For the philosophers, this means that we cannot so easily escape from Searle's Chinese room.)
All of this quantum mind nonsense seems to have stared with Roger Penrose and his ridiculous "theory". (Read: Shadows of the mind and The emperors new mind) He not only claims that the brain is a quantum system (possible, but totally unfounded) but also proposes a formula by which we can calculate how conscious something is! (He bites the ol' ontological bullet really hard, and goes on to claim that even an electron can be conscious, but only a little bit and only once in a great while.)
This article:
http://www.sciencemag.org/cgi/content/summary/287/5454/791?ck=nck
Very clearly outlines the biggest problems for the theory. This is likely where the "Brain is too hot" argument originated. It's a good one, and not likely to go away anytime soon.
More importantly, even if mother nature managed to work around the problem of a hot brain, it still doesn't get us any closer to consciousness. (See my first paragraph above) In the Penrose-Hameroff model, consciousness appears magically during collapse of the wave function. How they came to such a conclusion is beyond reason. That isn't science, it's mysticism.
Required reading for internet skeptics