Thread

1. __MatrixMan__ · 1790482592 · focus · HN ↗

   I feel like "is biology quantum?" gates are kept in a needlessly stringent way.

   They say that biological systems are too warm for quantum coherence to persist long enough to have meaningful effects. But if you have some molecule whose conformation is in a superposition of states--however briefly--and then the environment causes it to decohere and take on some fully determined non-quantum shape... that actual shape is still one of many possible ones into which it did not decohere. The environment has still hacked probability to trigger decoherence into this shape and not some other one, and evolution leans on this.

   If you took a classical bag and filled it with classical locks and classical keys and just shook it around for a while, none of those keys would end up in the locks. But because of this quantum lubricant, ligands binding receptors do find themselves in the appropriate conformation to facilitate signal transduction, even at low concentrations. It's absolutely astounding that it works at all, and in a fully classical world it wouldn't for the same reason that the keys don't end up in the locks when you shake the bag for a while.

   Biology is plenty quantum, and the people who are here to tell you it isn't are citing the abundance of interactions as evidence that it is not quantum, but it's through those many interactions that its quantum nature expresses itself.

   Maybe it's not spooky-action-at-a-distance style quantum. Maybe it's not indeterminate enough for this theoretical purpose or that one. If you're trying to cram god in there, well it might not be quite spooky enough for that, but so much of what happens in the macroscopic world would not happen if the quantum world were not as strange as it is, and that's doubly true for biology.

   1. joebig · 1790490756 · focus · HN ↗

      There is some inaccuracy here I think. Decoherence means washing out of interference phenomenon, viz. you will observe no fringes in the double slit experiment with incoherent source pair (they switch so rapidly as to end up plain grey). What is erased or overwritten in tiny timescales cannot have a residual resultant or guiding gulley effect, or as you say, freezing the pattern/steric landscape in a preffered state repeatably. It would be tantamount to observing the fringe pattern with incoherent sources, for all timescales.

      1. __MatrixMan__ · 1790517002 · focus · HN ↗

         Take flash memory for example. We read the bit via quantum tunneling. We don't have to wait for the electron to actually bounce out of its little box, we can detect the small probability that it might, and then we can act on that detection.

         So every time I act on the basis of such a read event, am I not being guided down one of gulleys that were set up by the designer of my device (or, analogously for biology, by evolution)?

         1. gus_massa · 1790520791 · focus · HN ↗

            We can't detect the probability, we only can detect electron that a passed. We meassury tiny currents.

            Do you have a link to this explanation?

            1. __MatrixMan__ · 1790527000 · focus · HN ↗

               I did some more reading and it turns out I've misunderstood flash memory. I thought it was read via tunneling, but it's written via tunneling. I appologize.

               This being the forum that it is, I was hoping to find an example of this sort of thing: <a href="https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC4066974&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC4066974&#x2F; but in electrical engineering instead.

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