I asked this question to OpenAI:
I received this as a forward:
Quote:
Modern research in quantum biology suggests that plants may use some of the universe’s most mysterious physical principles; quantum entanglement and quantum superposition; to move energy with astonishing efficiency. Although these effects were once thought to exist only in ultra‑cold laboratories, studies on photosynthetic complexes show that nature has been running quantum experiments for billions of years.
Inside a leaf, sunlight is absorbed by pigment molecules and converted into excitons; tiny packets of energy that must travel through a dense forest of molecular pathways to reach the reaction center. Classically, this journey should be slow and wasteful. Yet plants routinely achieve near‑perfect energy transfer, often above 95%. The question is how.
Experiments using ultrafast spectroscopy reveal that excitons do not choose a single path at first. Instead, they enter a state of quantum superposition, exploring many possible routes simultaneously. This allows the system to “test” all pathways at once and select the most efficient one in real time. Some models also suggest that entanglement between pigment molecules helps maintain coherence long enough for this quantum search to succeed, even in the warm, noisy environment of a living cell.
This phenomenon; sometimes called environment‑assisted quantum transport; shows that biological systems do not fight against molecular noise; they use it. Vibrations in the protein scaffold may help stabilize quantum coherence just long enough for energy to flow like water finding the smoothest channel.
In this way, plants demonstrate a quiet, elegant mastery of quantum physics, turning sunlight into life with a precision that still challenges our understanding of nature.
From the wall of Neil DeGrasse Tyson.
Unquote
I know that Mr Tyson is a respected commentator on science. But I'm having problem with the following: 'Experiments using ultrafast spectroscopy reveal that excitons do not choose a single path at first. Instead, they enter a state of quantum superposition, exploring many possible routes simultaneously. This allows the system to “test” all pathways at once and select the most efficient one in real time. ' We have gone together many times that in quantum 'anything', there is no way we can 'test' an in-between state. And 'all at once' will afford no interference to allow maximising probability amplitudes. Am I missing something, or is Mr Tyson is dumbing down for lesser mortals like me, or is he confused?
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OpenAI answered thus:
Your discomfort is well-placed. You’re not missing something basic—and you’re definitely not being “lesser mortal” here. What you’re reacting to is a metaphor that has slipped over a conceptual line.
Let’s separate what is solid physics from what is poetic overreach.
What experiments actually show (the solid part)
Ultrafast spectroscopy does show something remarkable in photosynthetic complexes:
After a photon is absorbed, the excitation (the exciton) is delocalized over several pigment molecules for a very short time (tens to hundreds of femtoseconds).
During that window, the system exhibits quantum coherence: oscillatory signals consistent with phase relationships between pathways.
Energy transfer efficiency is indeed very high (often quoted ~95%, though that number depends on definitions).
So far, no controversy.
Where the language goes wrong
This sentence is the culprit:
“They enter a state of quantum superposition, exploring many possible routes simultaneously. This allows the system to test all pathways at once and select the most efficient one in real time.”
This is not literally correct quantum mechanics. Your instincts are right.
1. There is no “testing” in quantum mechanics
Quantum systems do not:
evaluate options,
compare efficiencies,
or “select” a best path.
That language smuggles in classical optimization thinking (and a hint of teleology).
What actually happens is this:
The exciton evolves under a Hamiltonian determined by molecular couplings and the environment.
Some pathways have constructive interference, others destructive.
Paths that couple more strongly to the reaction center simply accumulate higher probability amplitude.
No testing. No decision. Just dynamics.
You and I have agreed on this point many times—and nothing here overturns that.
2. “All at once” does not mean “no interference”
This part is subtle, and it may be where the forward muddies things.
You wrote:
“‘All at once’ will afford no interference to allow maximising probability amplitudes.”
Here’s the correction:
Interference requires superposition, not sequential exploration.
What would kill interference is measurement or rapid decoherence.
In photosynthesis:
The exciton is not measured mid-flight.
The environment causes partial, not total, decoherence.
This allows interference briefly, before localization occurs.
So the system doesn’t “test paths one by one”; it interferes paths until the dynamics naturally funnel energy downhill.
3. Environment-assisted quantum transport (ENAQT) is real—but modest
This part of the forward is mostly accurate, though often overstated:
“Biological systems do not fight noise; they use it.”
What that really means:
Too much coherence → excitation gets stuck oscillating.
Too much noise → classical random walk (inefficient).
Intermediate noise helps break symmetry and prevent trapping.
Noise doesn’t guide the system intelligently—it just nudges it out of dead ends.
Think less “quantum search algorithm”, more “well-damped wave on a rough surface”.
About Neil deGrasse Tyson specifically
Two careful points:
This exact wording is very likely a paraphrase or misattribution.
Passages like this circulate widely and often get credited to Tyson, even when they’re stitched together from pop-science articles and talks. (Notice the Facebook-style cadence.)Even when Tyson discusses this topic, he usually leans metaphorical.
He’s a communicator first, and metaphors are his tools. But metaphors can become misleading when they’re read as mechanisms.
So no—you’re not catching him in a conceptual blunder so much as catching a metaphor pretending to be physics.
The clean, non-misleading way to say it
If I were to rewrite that paragraph in a way you’d probably accept:
After excitation, energy is briefly delocalized across several molecular sites. Quantum coherence allows interference between transfer pathways, enhancing transport toward the reaction center. Environmental interactions limit this coherence but also prevent trapping, resulting in highly efficient energy flow—without any measurement, testing, or selection by the system itself.
No magic. No intent. No violation of what we’ve already agreed quantum mechanics allows.
Bottom line
✅ Your objection about “testing” intermediate states is absolutely correct.
❌ The “selecting the best path” language is misleading metaphor, not physics.
⚖️ The real story is coherence + interference + controlled decoherence, nothing more mystical than that.
🧠You’re not resisting new science—you’re resisting sloppy storytelling.
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