(dear mod - I chose physics because the physics rather than the biology is further over my head. But if you think this belongs in Bio, I accede)

The link is a fairly general and simple description of what sounds very interesting to me.

Photosynthesis works 'by quantum computing'

http://www.rsc.org/chemistryworld/Issues/2007/May/PhotosynthesisWorksQuantumComputing.asp

Below is a rather dense - for me - 'letter' describing the process.

Letter

Nature 446, 782-786 (12 April 2007) | doi:10.1038/nature05678; Received 13 October 2006; Accepted 14 February 2007

Evidence for wavelike energy transfer through quantum coherence in photosynthetic systems

Gregory S. Engel1,2, Tessa R. Calhoun1,2, Elizabeth L. Read1,2, Tae-Kyu Ahn1,2, Tomás caron Manc caronal1,2,5, Yuan-Chung Cheng1,2, Robert E. Blankenship3,4 & Graham R. Fleming1,2

1. Department of Chemistry & QB3 Institute, University of California, Berkeley
2. Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
3. Department of Biology,
4. Department of Chemistry, Washington University, St Louis, Missouri 63130, USA
5. Present address: Institute of Physics of Charles University, 12116 Prague 2, Czech Republic.

Correspondence to: Graham R. Fleming1,2 Correspondence and requests for materials should be addressed to G.R.F. (Email: grfleming@lbl.gov).
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Photosynthetic complexes are exquisitely tuned to capture solar light efficiently, and then transmit the excitation energy to reaction centres, where long term energy storage is initiated. The energy transfer mechanism is often described by semiclassical models that invoke 'hopping' of excited-state populations along discrete energy levels1, 2. Two-dimensional Fourier transform electronic spectroscopy3, 4, 5 has mapped6 these energy levels and their coupling in the Fenna–Matthews–Olson (FMO) bacteriochlorophyll complex, which is found in green sulphur bacteria and acts as an energy 'wire' connecting a large peripheral light-harvesting antenna, the chlorosome, to the reaction centre7, 8, 9. The spectroscopic data clearly document the dependence of the dominant energy transport pathways on the spatial properties of the excited-state wavefunctions of the whole bacteriochlorophyll complex6, 10. But the intricate dynamics of quantum coherence, which has no classical analogue, was largely neglected in the analyses—even though electronic energy transfer involving oscillatory populations of donors and acceptors was first discussed more than 70 years ago11, and electronic quantum beats arising from quantum coherence in photosynthetic complexes have been predicted12, 13 and indirectly observed14. Here we extend previous two-dimensional electronic spectroscopy investigations of the FMO bacteriochlorophyll complex, and obtain direct evidence for remarkably long-lived electronic quantum coherence playing an important part in energy transfer processes within this system. The quantum coherence manifests itself in characteristic, directly observable quantum beating signals among the excitons within the Chlorobium tepidum FMO complex at 77 K. This wavelike characteristic of the energy transfer within the photosynthetic complex can explain its extreme efficiency, in that it allows the complexes to sample vast areas of phase space to find the most efficient path.

Does it seem possible that we may find more quantum computing processes in other life forms?

What do you think of this discovery?

quantum computing processes ...
What do you think of this discovery?

If depends on how the "quantum computing processes" are defined. Without definition the denomination of photosythesis as a quantum computing is just a sort of semantic calculation too, i.e. the tendency to increase the article impact by connecting it with another "popular" word. Can we derive/predict something new from such denomination?

Our brains alone may act much like quantum processors according to Dr. Penrose.

If depends on how the "quantum computing processes" are defined. Without definition the denomination of photosythesis as a quantum computing is just a sort of semantic calculation too, i.e. the tendency to increase the article impact by connecting it with another "popular" word. Can we derive/predict something new from such denomination?

Over my head. I am hoping that some of the responses will give me a better understanding of what they actually think is going on in these bacteria. I will do some research of my own so I can potentially ask intelligent questions to those with a greater understanding of physics.

Here's another take on the process.

http://www.physorg.com/news95605211.html

They do seem clear that previous explanations of what happens in photosynthesis are not adequately explained by classical physics and that quantum physical phenomena are at play.

Our brains alone may act much like quantum processors according to Dr. Penrose.

By latest observations, even the single neuron appears a much "smarter", then just a passive component of neural network.

http://www.nature.com/nature/journal/v450/n7173/full/nature06416.html

and another ones:

http://sci-con.org/2007/04/consciousness-in-the-single-neuron/
http://cogprints.org/3891/1/snt-9html.htm
http://www.sciencemag.org/cgi/content/full/319/5859/104

.. quantum physical phenomena are at play...

Indeed, but it still doesn't mean, we are inthe realm of quantum computation, until we declare all quantum physics phenomena as a sort of "quantum computing" phenomena. For example, every interaction of waves/branes can be interpreted as a sort of computation in certain extent, which renders the Universe as a multiplication machine.

http://superstruny.aspweb.cz/images/fyzika/aether/projective2.gif

Indeed, but it still doesn't mean, we are inthe realm of quantum computation, until we declare all quantum physics phenomena as a sort of "quantum computing" phenomena. For example, every interaction of waves/branes can be interpreted as a sort of computation in certain extent, which renders the Universe as a multiplication machine.

http://superstruny.aspweb.cz/images/fyzika/aether/projective2.gif

Thank you for the links, especially in the other post. I have copied them down to files and fill read them later.

If you look at the first link I provided in the OP...

My lay interpretation of this description of what they discovered is this.

Previously scientists thought that photosynthetic cells were passive in response to light. The light 'hit' the cells and sort of like random pachinko balls excitons set off reactions in the cell that gave energy to photosynthesis. Now it seems like the process is too efficient and also that the incoming energy is spread out evenly (for a moment?) in a coherent set of states. From these 'options' the best route is 'chosen'. another way of putting this is that quantum interactions allow something [computer, plant...] to evaluate potentials as if they were actual. It seems to me that quantum phenomena include things where a variety of potential states/qualities are 'present' equally. A blurring of the difference between potential and actual. Here, out of these, the cells are choosing - for want of a better word that potential that is best. Somehow with the lasers the scientists were able to see this 'variety of potentials' being present and this contradicted classical interpretations of what was happening.

I am trying to guess my way into this as a layperson. Not to propose a theory but to give you an idea of my specific ignorance and misinterpretations so it is easier for you to explain what I am messing up on. Or if I hit the mark, for me to get a sense of those parts also.

By latest observations, even the single neuron appears a much "smarter", then just a passive component of neural network.

http://www.nature.com/nature/journal/v450/n7173/full/nature06416.html

and another ones:

http://sci-con.org/2007/04/consciousness-in-the-single-neuron/
http://cogprints.org/3891/1/snt-9html.htm
http://www.sciencemag.org/cgi/content/full/319/5859/104

The note really says, that the mind is of quantum componants... therego, it must be right that superpositioning is inherent within the life of the human brain.

...really says, that the mind is of quantum componants... therego, it must be right ...
Such ultimate stance doesn't correspond the quantum uncertainty of human mind, does it?

MOD NOTE:

Please answer the question posed by the OP, or start another thread.

If you want to use SciForums as a chat room, it's probably easier to download Skype.

sowhat---
I read the Nature article over my lunch break. Another synopsis is here:
http://www.nature.com/nature/journal/v446/n7137/full/446740a.html;jsessionid=E835B211FCCD168BCB95683116 B7ACC1

It seems what is happening is that the experimenters shot some light at a protein which lives in plants. The photosynthesis process works (I'm just guessing here, but I think it's right) by turning the light pulse into an electric pulse. This electric pulse has to travel down a system of ``wires'', which transports the pulse to some region of the plant where the electrical energy is turned into chemical energy, which the plant can use to grow.

If I were just guessing, I wouldn't imagine that the electrical pulse was correlated with the properties of the light pulse---it seems that biologists generally thought that the transfer of the electric pulse was done in a more or less random manner. I think what these researchers found was that the two pulses WERE correlated, which means that the ``wires'' inside the plant must be very efficient at transferring electrical impulses, and the information transfer must happen in a quantum way.

``Quantum way'' means that it preserves the information stored in the initial light pulses. To take an extreme example, it is more or less like a cell phone. You talk into the cell phone, and the cell phone creates high energy photons which encode your voice. These photons are beamed to a tower and then to another cellphone, which takes the photons and recreates your voice.

MOD NOTE:
Please answer the question posed by the OP, or start another thread.
The pyschoceramics that infest SciForums are wont to pull threads off-topic because, if they actually did follow your advice, you would move their pseudoscientific claptrap to the pseudoscience forum or even to the cesspool.

Now, back to the OP:
I think that this article begs the question of the meaning of quantum computing. To me, this is just a quantum mechanical process of which life has "learned" to take advantage. The real computing (if you want to call it that) was done by the evolutionary processes that led to the extremely efficient harvesting of light energy done by photosynthesis. I suspect that the earliest forms of plant life were much less efficient than the current forms. As the ability to harvest light more efficiently yields an obvious competitive advantage, any mutation that conferred such an ability would have aided these primitive algae in the evolutionary struggle.

This article also hints at why the concept of quantum computing is having such a hard time taking root. In the 1940s there was a strong debate over which computing technique - analog or digital - was better. Unless you are an old fart, you probably don't even know what analog computers are. The basic idea was to build an electronic circuit rife with amplifiers, resistors, inductors, and capacitors whose differential equations were identical in form to those of some problem to be solved. This made the circuit an electrical analog of the problem, and hence running the device was tantamount to solving the problem. The biggest drawback with analog computers is that they aren't easily programmable. To solve a different problem one must build an entirely new circuit. Quantum computers are modern-day analog computers, and they are even harder to build than the clunkers that we used in the 1940s to do ballistic computations.

sowhat---
I read the Nature article over my lunch break. Another synopsis is here:
http://www.nature.com/nature/journal/v446/n7137/full/446740a.html;jsessionid=E835B211FCCD168BCB95683116 B7ACC1

It seems what is happening is that the experimenters shot some light at a protein which lives in plants. The photosynthesis process works (I'm just guessing here, but I think it's right) by turning the light pulse into an electric pulse. This electric pulse has to travel down a system of ``wires'', which transports the pulse to some region of the plant where the electrical energy is turned into chemical energy, which the plant can use to grow.

If I were just guessing, I wouldn't imagine that the electrical pulse was correlated with the properties of the light pulse---it seems that biologists generally thought that the transfer of the electric pulse was done in a more or less random manner. I think what these researchers found was that the two pulses WERE correlated, which means that the ``wires'' inside the plant must be very efficient at transferring electrical impulses, and the information transfer must happen in a quantum way.

``Quantum way'' means that it preserves the information stored in the initial light pulses. To take an extreme example, it is more or less like a cell phone. You talk into the cell phone, and the cell phone creates high energy photons which encode your voice. These photons are beamed to a tower and then to another cellphone, which takes the photons and recreates your voice.

Thank you for responding and for trying to focus attention on my OP.

In your cellphone analogy I assume we are not dealing with a Quantum phenomena. What makes it a quantum phenomena in the photosynthesis? I can see where the efficiency led them to notice that something other than 'classical' processes were at work. I am still not quite sure what these quantum processes are however. I took a stab above in post 7, I believe, at translating the article into lay terms. My lay terms that is and not with a lot of confidence. How far off do I seem to be?

[QUOTE]
Now, back to the OP:
I think that this article begs the question of the meaning of quantum computing. To me, this is just a quantum mechanical process of which life has "learned" to take advantage. The real computing (if you want to call it that) was done by the evolutionary processes that led to the extremely efficient harvesting of light energy done by photosynthesis.

I deeply regret having followed the article's lead by referring to quantum computing. You explanation above seems fine to me. I still find the idea that very simple life forms - compared to us - include in their make up processes that incorporate quantum phenomena in a technological way. But if we could leave aside the implications of that, if there are any.

My main interests right at this point are to understand what is happening, what the quantum phenomena are in these life forms.

I have been fussing around with a QM dictionary, looking up words like superposition, quatum coherence and phase. Any bridging to a layperson is appreciated.