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  But quantum coherence would allow the energy to test every 
  possible pathway simultaneously before traveling via the 
  quickest route.
Energy does not possess agency. A photon does not behave as Goldilocks anymore than rain drops do.

If there's anything engaging in "decision making" if we must call it that, it's the protein.

  In the weird world of quantum physics, a system that is 
  coherent can exist in many different states 
  simultaneously, an effect known as superposition.
Also silly.

The system does not exist in multiple states simultaneously. We just simply lack the ability to know or measure the true state, so we invent a hypothetical state to explain this on paper, and then proclaim victory for ourselves.

I suggest you educate yourself about Bell's Inequality.
i feel your comment is unnecessarily dismissive toward a healthy skepticism

if you can be the arbiter of said education then i'd suggest you educate wellyWellyWell, wWW, about Bell's Inequality and its innate response to wWW's comment

if i were to guess why you brought up Bell i'd guess it was because you read wWW's comment as suggesting classical mechanics can explain superposition with a robust enough measurement, but that Bell shows that classical mechanics are are too 'silly' to explain quantum mechanics?

i find that science as a verb often is the act of discovering previous understandings were inadequate to describe phenomena, yet pedantry is more often used to squelch skepticism stead stoke the flame of investigation

Yes, yes, it's very cute to couch a belief in imaginary worm holes through dimension X behind bland jargon like variable scoping.

And yes, just last month, incontrovertible evidence that with the knowledge of a particle's spin at site A, I can instantaneously infer another particle's spin at site B and always be correct. So magical.

http://www.nature.com/nature/journal/v526/n7575/full/nature1...

But not because the particle landing at site B had already possessed a spin we could not measure at the time of emission. No!

The spin was all things to all people when emitted, and would remain as such until after we so courteously ask site A's particle to reveal its spin!

Bell says that the spin instantaneously traveled through a worm hole, across space and time, whispering in the ear of the site B particle, so that it could poof! Change it's mind!

Bell says no unknowable secrets allowed.

Bell says everyone can have everything.

Bell says it's not because of something we can't determine.

Bell says it's because of a special message transmitted in a way no one can intercept. Not even him!

Bell says we must have our love notes dictated to us after they are sent, and only then may true love be known! Until then, the notes are written in all languages, as both hate and love, war and peace!

Bell says Bob won't love Alice until Alice loves Bob! That Bob's note re-writes itself before his love can be unrequited because Bob refuses to get dumped!

To sum up, with less snark, because I'm not directing the snark at you... It's directed at Bell, as posthumous snark, since I'm sure he won't feel it.

Anyway, I don't ascribe to the school of thought that tells us that simply because superposition works on paper, that such a predictive tool accurately reflects events occurring in reality.

It may help us, to understand and deal with curious events, but Bell hasn't accomplished anything profound in making his pronouncements.

All he did was insist that people shift conceptual placeholders about, to help reorganize a mental model for imagining representations of an idea. To regard his hand-wavy declarations as a crystallized description of reality is nonsense.

Ask this: If something cannot be touched, known or inferred, then how can he assert that reality reshapes itself in reverse upon reaching an event, or that an untouchable relationship persists behind the facade or our reality?

Furthermore, his arguments are pure semantics. One is not allowed to presume independent unrelated inaccessible slots, one must assume related inaccessible slots. Even though the relationship of the slots is not actually revealed until after it no longer matters whether there was a relationship or not. Oh, and by the way, that relationship transcends reality as we know it, possibly implying a parallel channel of communication, external to our world.

Sure, so much better than just stating that there is information missing from our representational model at certain moments in the sequence of events.

i am always confused when bell comes up and people use it as an argument for 'the probabilistic nature of quantum mechanics'

as i stated in my comment defending your original skepticism: 'i find that science as a verb often is the act of discovering previous understandings were inadequate to describe phenomena'

bell's inequality was a direct response to the Einstein-Podolsky-Rosen paradox which wanted to assert philosophically the inadequacy of quantum mechanics

conversely bell shows empirically the inadequacy of classical mechanics

which seems uncontroversial.. how many times historically have we shown contemporary classical mechanics to be wanting?

bell, to me, simply says if you wish to find relation between bodies associated with classical mechanics and bodies associated with quantum mechanics you are going to have to do better, and i'd argue.. on both fronts

why do you think its 'silly'?

can you show that, or explain how, a system 'does not exist in multiple states simultaneously'?

this video of lightning(o) can act as an example of a 'system' searching a tree structure in multiple states simultaneously

(o) https://www.youtube.com/watch?v=7kI1d7DMbco

Can you show or explain how it does? Welcome to the world of belief systems and preferences.

The lightening is not "searching" anything. Inequalities within the system are resolving to destinations and expending themselves. That energy is discharged into many endpoints merely indicates that the amount of energy on one side of the inequality can overflow many receptacles on the receiving end, before overflowing all the way to the ground state offered by the earth.

Is this really so hard to comprehend? In a non-vacuum filled with charged moisture, why should it surprise anyone that mid-air electrical arcing should take curious paths? Why must the lightening be anthropomorphized, such that it "thinks" and then "chooses" the "best" route to the ground?

If the static charge had been less intense, and satisfied an equilibrium before even reaching in the ground, would it still have "chosen" anything?

forgive me, i was unaware this was a semantic argument

i thought your issue was with coherence 'resolving' multiple routes simultaneously, specifically the simultaneous aspect

by using the word 'search' i was anything but suggesting that we should anthropomophise lightning, but i'd argue the article failed to do the same for light

i created an opportunity for you to lash out by using a vague term to simplify a description and i apologise to posterity for that

but you're derailing any substantial discussion on the science with a strawman

if you read the study the words: 'think','choose', and 'search'; are completely vacant from the paper.. you're projecting

    If the static charge had been less intense, and 
    satisfied an equilibrium before even reaching in the 
    ground..
fun aside, this is potentially exhibited in the video

if you watch the video one of the routes the original bolt takes loops back in on itself, right at the top of the frame

then it seems a second bolt follows that same loop, there is a momentary irradiance

if you watch the lower branches, some that had faded irradiate as well

possibly implying the original bolt may have lacked sufficient energy to reach the earth, but the second was able to piggy back on the original's expended effort

or it all could just be artifacts of the camera and its sensors

just such a cool video

Wow! Thanks for the link. I never knew such a field even existed!
"whether coherent quantum processes play a nontrivial role in biology" (from the paper) is very controversial. The idea was that coherence would make photosynthesis more efficient. If they're right about this mutation switching between coherence and not-coherence, they should now proceed and test the efficiency of the two photon harvesting modes.
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What the heck is this article talking about!

Foremost, coherence is a property of tbe light and I dont see any queezing or fock states so the quantum nature is not important. Does the absoption process happen coherently with other protiens? Would this reduce the total amount of light possible to absorb as it requires rejecting the incoherent photons?

What are these guys talking about?!

My (vague) understanding of the phenomenon being discussed is that it was discovered that, in some of the proteins involved in photosynthesis, the electrons were passed around via multiple, quantum-entangled pathways. This allows (supposedly!) better energy transmission than classical physics would.
can anyone speak to the link between coherence and tree traversal?

the article and paper both seem to assume this connection should be known to the reader while also suggesting this paper's discovered methods could answer the relation, could someone bring me up to speed?

    “
    It was assumed the energy gets to the reaction centre
    in a random fashion, like a drunk staggering home.
    But quantum coherence would allow the energy to test
    every possible pathway simultaneously before
    travelling via the quickest route.
    ”
how complex are these routes? the paper cites that the team was able to use 'Crystallographic analyses [to] reveal two very different quaternary structures' but i was unable to find any information on the complexity of these structures

Traveling salesman problems can quickly become unwieldy so even if you allow for the route traveled to be thought to be the quickest, testing this hypothesis is equally intractable with current mathematics

from the paper:

    "from the insertion of a single amino acid, 
    the two αβ monomers are rotated by ∼73° to an 
    “open” configuration in contrast to the “closed”
    configuration of other cryptophyte PBP"

    "A central biological question is whether the
    presence of long-lived electronic coherence in the 
    light-harvesting proteins results in a selective 
    advantage for the algae—for example, is coherence 
    important for efficient light harvesting? If the 
    emergence of long-lived electronic coherence gives 
    cryptophytes containing the closed-form PBP a 
    selective advantage over the ancestral cyanobacteria 
    and red algae, it would seem that the Hemiselmis 
    cryptophytes, with their open-form PBPs, have lost 
    this advantage."
to summarise the paper would one say that the discovery of a new 'open' configuration in a light harvesting algae has given us a mechanism to, in the future, test the relevance of coherence to efficient routing?