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Science

Scientists Find Link Between Photosynthesis and 'Fifth State of Matter' (phys.org) 56

Louise Lerner writes via Phys.Org: Inside a lab, scientists marvel at a strange state that forms when they cool down atoms to nearly absolute zero. Outside their window, trees gather sunlight and turn them into new leaves. The two seem unrelated -- but a new study from the University of Chicago suggests that these processes aren't so different as they might appear on the surface. The study, published in PRX Energy on April 28, found links at the atomic level between photosynthesis and exciton condensates -- a strange state of physics that allows energy to flow frictionlessly through a material. The finding is scientifically intriguing and may suggest new ways to think about designing electronics, the authors said.

When a photon from the sun strikes a leaf, it sparks a change in a specially designed molecule. The energy knocks loose an electron. The electron, and the "hole" where it once was, can now travel around the leaf, carrying the energy of the sun to another area where it triggers a chemical reaction to make sugars for the plant. Together, that traveling electron-and-hole-pair is referred to as an "exciton." When the team took a birds-eye view and modeled how multiple excitons move around, they noticed something odd. They saw patterns in the paths of the excitons that looked remarkably familiar. In fact, it looked very much like the behavior in a material that is known as a Bose-Einstein condensate, sometimes known as "the fifth state of matter." In this material, excitons can link up into the same quantum state -- kind of like a set of bells all ringing perfectly in tune. This allows energy to move around the material with zero friction. (These sorts of strange behaviors intrigue scientists because they can be the seeds for remarkable technology -- for example, a similar state called superconductivity is the basis for MRI machines).

According to the models [...], the excitons in a leaf can sometimes link up in ways similar to exciton condensate behavior. This was a huge surprise. Exciton condensates have only been seen when the material is cooled down significantly below room temperature. It'd be kind of like seeing ice cubes forming in a cup of hot coffee. "Photosynthetic light harvesting is taking place in a system that is at room temperature and what's more, its structure is disordered -- very unlike the pristine crystallized materials and cold temperatures that you use to make exciton condensates," explained [study co-author Anna Schouten]. This effect isn't total -- it's more akin to "islands" of condensates forming, the scientists said. "But that's still enough to enhance energy transfer in the system," said Sager-Smith. In fact, their models suggest it can as much as double the efficiency.
The findings open up some new possibilities for generating synthetic materials for future technology, said study co-author Prof. David Mazziotti. "A perfect ideal exciton condensate is sensitive and requires a lot of special conditions, but for realistic applications, it's exciting to see something that boosts efficiency but can happen in ambient conditions."
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Scientists Find Link Between Photosynthesis and 'Fifth State of Matter'

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  • Seriously? (Score:5, Informative)

    by Rei ( 128717 ) on Tuesday May 09, 2023 @05:16AM (#63508331) Homepage

    "When a photon from the sun strikes a leaf, it sparks a change in a specially designed molecule. The energy knocks loose an electron. The electron, and the "hole" where it once was, can now travel around the leaf, carrying the energy of the sun to another area where it triggers a chemical reaction to make sugars for the plant."

    What an awful description of the electron transport chain [wikipedia.org].

    • by Anonymous Coward on Tuesday May 09, 2023 @06:54AM (#63508411)

      Yes, a late US Senator from Alaska described it much better:

      Plants want to deliver vast amounts of energy over the Photosynthesis. And again, the Photosynthesis is not something that you just dump electrons in. It's not a hole. It's a series of chains. And if you don't understand, those chains can be pulled and if they are pulled, when you put your electron on, it gets in line and it's going to be delayed by anyone that puts onto that chain enormous amounts of electrons, enormous amounts of electrons.

      - Ted Stevens

      • Oh... so plants are "a series of tubes", then? Sounds pretty accurate.
        • Comment removed based on user account deletion
          • And so... Al Gore invented plants.

            Also the AlGorithm and the expressway Gore point. B-)

            Seriously though: What Al Gore did was promote legislation to legalize and encourage private use of the internet, letting it grow from a military and educational institution project with tight restrictions on access and commercial use to a general access communications medium with commercial use explicitly allowed.

            In other words, he legalized spam.

        • I wonder if I can get ChatGPT to write a paper about planet-based Internet and publish it in Nature.
      • Given that my mother can't really figure out the internet, when not to click on links, or that the power supply doesn't plug into the ethernet jack, I think Sen Stevens did a reasonable job on trying to explain the new internet to those without any technical background.

        In a very old joke book was an explanation about how radio worked. Its like taking a very long dog that stretches from Los Angeles to New York. If you step on the tail in Los Angeles then it will bark in New York. So radio is just like tha

        • Watch out buddy! PETA is going to come after you for stepping on the tails of dogs.

          They have already broken into the lab of Schrodinger trying to find the box that is imprisoning a cat with a poison gas vial. What a horrible thing to do to a cat!

    • by dfghjk ( 711126 )

      But it's got the "specially designed" terminology built-in. Makes Ken Ham's and William Lane Craig's job easy.

    • When a photon from the sun strikes a leaf, it sparks a change in a specially designed molecule.

      I stopped reading at the word "designed".

      • by Anonymous Coward

        When a photon from the sun strikes a leaf, it sparks a change in a specially designed molecule.

        I stopped reading at the word "designed".

        I stopped reading my dictionary when I got to the word "metaphor."

    • Not really, all the wikipedia page has of relevance is this "Here, light energy drives electron transport through a proton pump".

      Don't take the "travel around the leaf" from the summary too literally, they are talking about a scale below even the electron transport chain.

      • Re:Seriously? (Score:4, Informative)

        by Rei ( 128717 ) on Tuesday May 09, 2023 @11:03AM (#63508849) Homepage

        Yeah, that's not even remotely "all the Wikipedia page has of relevance". And all of what was written was misleading or wrong, not just the "travels around the leaf" part. Compare:

        "When a photon from the sun strikes a leaf, it sparks a change in a specially designed molecule. The energy knocks loose an electron. The electron, and the "hole" where it once was, can now travel around the leaf, carrying the energy of the sun to another area where it triggers a chemical reaction to make sugars for the plant."

        To:

        "For a photon to be utilized by a plant for energy production, it is captured by the porphyrin ring of chlorophyll in photosystem 2 (PSII), with the excitation primarily concentrated at the P680 centre, with approximately 4 photons leading to the splitting of two water molecules to oxygen and four hydrogen ions (free protons) in the lumen (thylakoid interior), with two free electrons and two hydrogen ions from the stromen (thylakoid exterior / chloroplast interior) used to reduce plastquinone (PQ) to PQH2. This is mobile along the thylakoid membrane and functions as an electron carrier to cytochrome C, wherein the two hydrogen ions are transported to the lumen (interior). These are each transported individually by plastocyanin (by changing the oxidation state of its copper complex), which again is mobile across the thylakoid membrane to photosystem 1 (PS1), where - through ferredoxin and ferredoxin-NADP reductase - NADP+ (a proton carrier) gains a proton, to NADPH. Through the process, the energy of the photons is utilized as work through the electron transport process to increase the proton concentration inside the lumen (interior) relative to the stroma (exterior). This proton gradient is then utilized by ATP-synthase, which is effectively a several-thousand-RPM proton-powered motor, with a rotor and stator; the rotation of the rotor against the stator is used to physically bind phosphate groups onto ADP, to form ATP, a sort of energy currency of the cell. ATP and NADPH are then used to drive the light-independent Calvin cycle, which ultimately fixes carbon as 3GP, which is used to build glucose, which in turn is used to build sucrose."

        Or to simplify it and reduce it to the same length as her statement:

        "Photons captured by chlorophyll split water to O2 and free protons and, through a multi-step electron transport chain involving physical charge carriers, transport additional hydrogen ions across a membrane, as well as creating NADPH. The protons fuels a hydrogen-powered "mill" that makes ATP, and the NADPH and ATP drive sugar production"

        Things that are wrong about her statement:

          * Not all photons that "strike a leaf" are utilized (the majority are not), and photosynthesis also happens (to a lesser extent) in non-leafy tissue.
          * Chlorophyll is not "designed"
          * "sparks a change in a specially designed molecule" is a beyond vague filler.
          * Electrons are not "knocked loose", but rather harnessed (at least mostly).
          * "Where it once was" was in PSII, and that absolutely does not "travel around the leaf"
          * The electron itself is only harnessed over the short distances of the electron transport chain, and also does not "travel around the leaf" during this process (or even around the chloroplast, or even around the thylakoid - just a tiny distance on the thylakoid membrane).
          * The electron is long on its merry way and out of the story by the time the proton gradient is used to make ATP, and those protons are in turn long out of the story and on their merry way by the time that the produced ATP and NADPH are used to drive the Calvin cycle
          * So of course it is not "triggering" (let alone being harnessed) in the Calvin cycle itself.
          * The Calvin cycle itself does not even form sugars; it forms 3GP, which is in turn used to make sugars.

        Given that the point of this article is to understand that photosynthesis involves exciton condensates, given that her statement is so utterly wrong, I'm left without a clue exactly where exciton condensates are supposed to fit into the picture.

        • by Rei ( 128717 )

          ED: G3P, not 3GP!

        • Compare:

          "When a photon from the sun strikes a leaf, it sparks a change in a specially designed molecule. The energy knocks loose an electron. The electron, and the "hole" where it once was, can now travel around the leaf, carrying the energy of the sun to another area where it triggers a chemical reaction to make sugars for the plant."

          Or to simplify it and reduce it to the same length as her statement:

          "Photons captured by chlorophyll split water to O2 and free protons and, through a multi-step electron transport chain involving physical charge carriers, transport additional hydrogen ions across a membrane, as well as creating NADPH. The protons fuels a hydrogen-powered "mill" that makes ATP, and the NADPH and ATP drive sugar production"

          Lets compare. But keep in mind the intended audience. The phys.org version is understandable without knowing any science. Molecule and electron are the most challenging concept and most people would have at least a vague idea of what those are -- not an accurate idea, but at least something to work with. Version 1 delivers an understandable impression of what happens. Pretty much all the details are of course wrong, but the the general idea is clear.

          The 2nd version may be more accurate, but that is not hel

          • by ceoyoyo ( 59147 )

            The phrase "physical charge carrier" caught my attention.

            • by Rei ( 128717 )

              Perhaps "mobile charge carrier" would be better. Rather than, say electrons moving along wires, they're in effect transported by mobile molecules that move (short distances) across the thylakoid membrane

        • "Photons captured by chlorophyll split water to O2 and free protons and, through a multi-step electron transport chain"

          No, that's not what "electron transport chain" means. PSI/PSII are part of the electron transport chain, but to say the exciton transport from the light harvesting complex to the reaction centre is a multi-step electron transport chain is using the word incorrectly.

          The electron transport chain is what is powered by protons generated in the PSI/PSII reaction centres, the paper is about the t

          • by Rei ( 128717 )

            PSI/PSII are part of the electron transport chain,

            And apparently you think that somewhere in that sentence you think I said that they're not?

            Would you prefer "through the rest of the electron transport chain"? I was really heavily trying to cut down word count to match the original in length.

            to say the exciton transport from the light harvesting complex to the reaction centre is a multi-step electron transport chain

            Great attack against something I never even remotely said.

            • by Rei ( 128717 )

              Also:

              The electron transport chain is what is powered by protons generated in the PSI/PSII reaction centres, the paper is about the transport of excitons inside PSI/PSII to the reaction centres. The electron transport chain is tangential.

              I was working with the author's summary, where one had no bloody clue what part of the process she was trying to describe. I assumed she was describing the whole electron transport chain, as she talked about the electron "traveling around the leaf", which I assumed to be a

        • For a photon to be utilized by a plant for energy production, it is captured by the porphyrin ring of chlorophyll in photosystem 2 (PSII), with the excitation primarily concentrated at the P680 centre, ...

          As I recall, the chlorophyll molecules are arranged in long stacks, with only the end molecule of each stack coupled to the next stages of the reaction chain. The excitation is able to transfer between the molecules of the stack (without loss, of course), by a quantum mechanical coupling mechanism that (w

          • by Rei ( 128717 )

            Thylakoids are long stacks. The electron transport chain occurs at countless photosystems across the thylakoid surface. Thylakoids are macroscopic - no quantum effects relate to them as a whole.

      • Don't take the "travel around the leaf" from the summary too literally

        Should we also not take the "5th state of matter" seriously either because there are at least two known other states - quark-gluon plasma and bose-einstein condensate - which have the advantage of actually being real states of matter so, even if you think that this does qualify as a new state (which I would disagree with) it is at best a 7th state of matter.

        • As the anon said, they are claiming it's a condensate.

          A somewhat contentious claim though, the Wikipedia page on the Fenna–Matthews–Olson complex says it's a long running controversy since a 2007 paper by Engel. That's far more relevant Wikipedia page than the one on the Electron transport chain BTW.

    • Yeah, chlorophyll is an an amazing molecule, but... "designed"???

      Who exactly was the designer?

  • by e**(i pi)-1 ( 462311 ) on Tuesday May 09, 2023 @06:00AM (#63508367) Homepage Journal
    Sounds a bit what an AI could do: 1) Pick two random scientific topics or terms. 2) Feed into midjourney for illustrations. 3) Seed into GPT4 to get an article 4) Do a publicity stunt 5) Goto 1). Examples: Chaos + Fractals, Fuzzy + Logic, Many world + time travel, Holographs + Universe, Strings + particles, relativity + quantum mechanics, Quantum + Black hole, Black holes + quantum computing, Wormhole + Monte Carlo, machine learning + quantum entanglement, quantum computers + lattice QCD, quantum + encryption, photosynthesis + 5th state of matter.
  • MRI (Score:5, Informative)

    by John Smith 2309 ( 10378058 ) on Tuesday May 09, 2023 @06:04AM (#63508369)
    "for example, a similar state called superconductivity is the basis for MRI machines" - No. No, it is not. MRI machines use superconducting magnets to create the necessary magnetic field gradients, but the basis for MRI is not superconductivity. It is magnetic resonance of isotopes of certain atomic nuclei excited by a radio frequency pulse of electromagnetic radiation. MRI could be performed without superconducting magnets.
    • by Rei ( 128717 )

      Hah, I missed that part, as I broke off earlier to criticize their awful description of the electron transport chain. ;)

      Phys Org needs better writers.

    • by bobm ( 53783 )

      MRI is (to some extent) being done without superconductor magnets

      https://www.science.org/conten... [science.org]

      Pretty interesting, much lower magnetic field.

    • by njvack ( 646524 )

      MRI could be performed without superconducting magnets.

      Not just could; you can buy a portable low-field MRI with no superconductors today:

      https://hyperfine.io/ [hyperfine.io]

      Image quality and scan times aren't as good as you get from a traditional superconducting magnet at 3T, but you can wheel this thing around and plug it into a 120V outlet.

      • by Rei ( 128717 )

        Is it weird that I suddenly have a desire to own a MRI?

        • My dream is to stop in at a CVS once per year for 10 minutes and step into a machine that scans your skin at various wavelengths and does a full-body MRI and a blood draw and then inspects every cubic cm of it for any of thousands of diseases. I definitely think we're getting a little closer year by year.
        • You can also get ultrasound machines [amazon.com] for pretty cheap, and they're lots of fun. You can scan your foot (or anything else) to see what's inside it.
  • At least this article shows that we are still continuing research into the fundamental fifth state of matter. I know Penny Arcade had documented the initial work a while ago, and I had lost track of who was experimenting in the field.

    https://www.penny-arcade.com/c... [penny-arcade.com]

  • To the long, long list of things that have to be "just so" to support life, you can add the molecule that powers photosynthesis. Only in this case, you have to face the fact that there are something like 10^300 (!) possible combinations of foldings in the 250 enzymes that make up that molecule. That is not just a "big number", it's an almost impossibly big number. For comparison, there are 10^33 objects in the entire universe.

    I am not here to tell you exactly how we got to the point where this molecule's en

    • by nasch ( 598556 )

      this molecule's enzymes folded in exactly the one, right way to convert sunlight to energy

      You would have to first demonstrate that there is in fact only one right way.

    • by Anonymous Coward
      Of all the ways the tea leaves could've tried in the bottom of my kettle, they dried in this particular way. {Massive logical leap}, therefor that is the only possible way for them to dry, and the unlikeliness of any particular result of rolling a thousand dice, means that what they ended up showing was divinely inspired.
  • Comment removed based on user account deletion

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