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Featured I Life on the Edge: is it still alive?

  1. Apr 25, 2017 #1

    sophiecentaur

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    I recently read ' Life on the Edge" by Jim Al-Khalili and Johnjoe McFadden. It was very readable and it got me quite convinced about the whole idea. Al-Khalili is a very presentable broadcaster / writer and offers an attractive case. But it was written some while ago and Google hasn't much to offer about subsequent work. The topic has appeared on PF several times but always seems to die an early death, with pretty short threads and lack of momentum.
    Has anyone read more recent stuff (something as approachable as that book, preferably)?
    The connection between Biology and QT has a good pedigree (going back to Schrodinger etc.) so it can't be just written off. Have the past threads died just because of lack of interest or do they stray too far into the realms of Nutty Science? The statistics of biological processes are fairly critical and QM seems to account for tipping the balance in favour of survival.
    I would love to read some well informed opinions about this.
     
  2. jcsd
  3. Apr 25, 2017 #2
    Cliff notes please.
     
  4. Apr 25, 2017 #3

    sophiecentaur

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    I learned a new phrase!!! Cheers
    This link is a more recent talk he gave (2015). Entertaining and a bit flowery but it has the message of the book. The intro puts it better than I would. :smile:
     
  5. Apr 25, 2017 #4

    DrChinese

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    Some of it is fringe. Or most, depending on perspective. Generally, this forum is for discussion of generally accepted science. Speculative ideas would not be appropriate. A specific example from the reference: "Jim Al-Khalili rounds up the extremely new, extremely strange world of quantum biology, where something Einstein once called “spooky action at a distance” helps birds navigate..." That's entanglement, and there is no way to use entanglement to assist in navigation - much less by a bird.
     
  6. Apr 25, 2017 #5

    sophiecentaur

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    Did you read what was written or just the extract from the reference?
     
  7. Apr 25, 2017 #6
    I can see how it would be easy to confuse or deliberately exploit phenomena like pack dynamics with some spooky QM entanglement.

    I have a neighbour just spent $1000+ on a frequency / energy machine that outputs quantum frequencies to cure her cancer, stopped radiotherapy treatment because she believes so strongly in the device.

    Too much scope for exploitation in quantum biology arena IMO.
     
  8. Apr 25, 2017 #7

    sophiecentaur

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    I can understand someone thinking that. There's a lot of 'magic' about still.
     
  9. Apr 25, 2017 #8
    Specifically regarding this one point, apparently there's been real research for some years now. What the current status is, I have no idea; but Google is not shy about coughing up search results for years from 2007 up to 2013 at the least; I didn't need to look very hard.

    For popular articles, see this undated article from the American Physical Society's "Physics Central" web site: "Migration via quantum mechanics." Also this 2011 article from US News: Quantum Compass for Birds. Various researchers and research teams are mentioned, including Thorsten Ritz, a biophysicist at UC Irvine; here's his academic research page - https://www.physics.uci.edu/~tritz/Research/research.html - and here's a 2007 paper he was an author on: http://sites.biology.duke.edu/johnsenlab/pdfs/pubs/light magneto.pdf

    Here's a 2013 paper from Physical Review E on "Quantum coherence and entanglement in the avian compass," by Pauls et al, mostly U.S.-based researchers.

    And here's an interesting 2011 news feature from Nature.com on "Physics of life: The dawn of quantum biology."

    Lots more I'm sure.
     
    Last edited: Apr 25, 2017
  10. May 2, 2017 #9

    sophiecentaur

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    I really couldn't tell from Al-Khalili's presentation just how believable the whole thing is. He's very convincing but, otoh, he is an accomplished Science broadcaster (aka journalist aka instantly subject to suspicion). The topic smacks a bit of snake oil and homeopathy and can only be assessed by someone who really knows about these things. The other topics he delivers are much more main stream. He has a regular BBC Radio 4 slot "The Life Scientific" (I think BBC iPlayer is available worldwide) in which he talks to a range of very well regarded Scientists from a range of fields. They presumably rate him fairly well.
    But at least it hasn't been totally discredited. It's clearly waiting to be taken up by a few more creditable researchers. You can imagine why it's not had universal acclaim.
     
  11. May 2, 2017 #10
    Hi Sophie:

    I must confess from reading the summary of the book
    is doesn't sound like a book I would want to read.
    From your reading, can you post a short summary of any specific scientific conjectures the book offers.

    The following seems like the "grabber" quote.
    Even in an age of cloning and artificial biology, the remarkable truth remains: nobody has ever made anything living entirely out of dead material. Life remains the only way to make life. Are we still missing a vital ingredient in its creation?​
    In the context of the quote
    Jim Al-Khalili and Johnjoe Macfadden reveal that missing ingredient to be quantum mechanics; the phenomena that lie at the heart of this most mysterious of sciences​
    does the book propose anything scientifically observable that makes it plausible that QM is the "heart" of life?

    One observation: on our planet it took normal chemical processes several hundred million years before the first living cells appeared. Science has only been working on anything close to "creating life" for a few decades, and in my view there has there has been some actual promising progress. For example:
    I get it that replicating RNA is not yet life, but as Nobel laureate Christian de Duve has argued, the "RNA World" preceded the origin of cells.

    Regards,
    Buzz
     
    Last edited by a moderator: May 8, 2017
  12. May 2, 2017 #11

    DrChinese

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    I think I had looked at it a while back, but the blurb alone stopped me cold this time. It would be reasonable to explain ANY theoretical basis for being able to migrate/communicate with entangled anything before asking whether birds use such a mechanism.

    In other words: there is no currently existing entanglement mechanism that I am aware of that supports this as a basis for further study. It would require new physics. If that is hidden in the article, I would welcome it being presented. (As opposed to sending us on a treasure hunt.)

    On the other hand, one of the primary purposes of requiring peer-reviewed references - which this is not by a long shot - is to save us from discussing things which have no current theoretical support. I am sure that fringe science produces "hits" from time to time, but there is no particular reason to boost the fringe *because* it is the fringe. There is plenty of existing mainstream research in entanglement. What it is providing every week is pretty amazing stuff.
     
  13. May 2, 2017 #12

    Strilanc

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    Actually, there is. The proposal is that the mechanism (some) birds use to detect the direction of the Earth's magnetic field involves some short-lived entanglement. Seth Lloyd talked about it in a lay-level talk at the Perimeter Institute [see 39:55]:

     
  14. May 2, 2017 #13

    DrChinese

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    I am going to call that out. As far as I know - which is hardly conclusive :biggrin: - could be recreated in a apparatus and demonstrated to show direction of the earth's magnetic field.

    I don't care who said it, a suitable reference for the speculative science is appropriate. As to it being speculative, I quote: "The only explanation that people have been able to come up with..." That's speculation, my friend. Or how about this:

    "The rate at which the spins of the electrons rotate is proportional to the strength of the Earth's magnetic field and also to its orientation." That's new to me (rotation speed and orientation of a pair of a pair of entangled excited electrons having a measurable dependency on a weak magnetic field), although I am open to be corrected. And how would a bird sense that rate anyway?
     
  15. May 2, 2017 #14

    Strilanc

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    The reference is "Magnetic Compass of Birds Is Based on a Molecule with Optimal Directional Sensitivity" by Ritz et al, 2009.

    The paper should contain or reference all this information. Based on skimming the paper it looks like the details you want might be in https://www.nature.com/nature/journal/v453/n7193/full/nature06834.html [Broken].

    Why do you find the dependence between magnetic field and rotation to be surprising? Electron spin precesses in a magnetic field. Make the field stronger, and it precesses faster. Change the orientation of the field, and you change the axis of the precession. In the case of a singlet state, the electrons will precess in opposite directions so in effect they will precess into (and out of) a triple state that depends on the orientation of the magnetic field at a rate that depends on the strength of the magnetic field. The chance of measurements agreeing vs disagreeing at some fixed time after the creation of the singlet would then tell you details about the magnetic field. (Of course in a bird this all has to somehow translate into a neuron spiking or not.)
     
    Last edited by a moderator: May 8, 2017
  16. May 2, 2017 #15

    DrChinese

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    First, this is a reference to a biophysical journal and not a quantum physics journal, as I would expect a suitable reference on entangled states. The current scientific consensus on this is: in animals, the mechanism for magnetoreception is currently unknown (assuming it exists) although there are hypothetical mechanisms under study.

    Second, "spooky action at a distance" is nowhere involved. The hypothesized concept is essentially classical in the sense that it is about Zeeman interactions. The hypothesis is that molecules in a triplet state act differently in a magnetic field than those in a singlet state.

    Third, their conclusion includes this comment: "We are currently not aware of any observations of radical pairs in biology that immediately match our suggested design. ... Our discussion of a possible realization is by necessity speculative, and alternatives cannot be excluded.... we were able to identify a unique type of radical pair as the only one consistent with experimental observations." Basically, they think their hypothesis is correct because they can't figure out any other explanation.

    My review of the physics (which should hardly be considered authoritative) is that there are suppositions upon suppositions required to make sense of this. We really should not be discussing this material in the Quantum Physics forum until it passes the sniff test.
     
  17. May 2, 2017 #16

    sophiecentaur

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    I found it very readable and well written. I read a lot of fiction (not pulp) and not a lot of popular science (not cover to cover, at least) but I got through this book very quickly. Trouble with books / films /plays /music is that you need to try them before you can say Hit or Miss.
    Thanks for your (and others') comments about the topic. I will wait to see if anything develops.
     
  18. May 2, 2017 #17
    As one of the more recent pop-sci stars I think Jim Khalili is mostly right on the ball.
    Able to describe complicated science ideas to anyone older than 8, yet still be respected by people less than 80
     
  19. May 9, 2017 #18
    .
    Isn't that the same logic you used to arrive at your conclusions; "...there is no way to use entanglement to assist in navigation - much less by a bird...." ?
     
  20. May 9, 2017 #19

    DrChinese

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    :welcome:

    Maybe, let's see. The difference is that entanglement cannot be used for signalling, and it requires post selection on time frames resolved to billionths of a second - far too small a window for any cell to be able to respond accurately. There are many further conceptual issues in the hand-wavy explanation offered as a speculation. What I am saying is that there is no scientific leg to stand on in current science of this area. If someone could first construct a compass using quantum entanglement, then we would have something to discuss as it relates to a bird. But that has yet to happen.

    So I am saying: "there is no known science in support, so they are wrong." That's a big difference from saying "there is no known science in support, but we are right anyway." You can justify ANYTHING by merely saying that something different *could* be discovered in the future. But that is not the standard used at PhysicsForums:there must be current theory or evidence. I absolutely question even the initial premise that birds (or fish) navigate by magnetism. What little I have seen on that is terrible, to put it mildly. The study featured 12 "confused" birds.
     
  21. May 9, 2017 #20

    Strilanc

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    What? The paper isn't speculative in the sense of proposing new physics, it's speculative in the sense of claiming specific known physics is happening in some particular environment (i.e. in a bird's eye). They aren't using entanglement to communicate, they're just having a singlet state last long enough to rotate a bit before recombining in some way.

    I also feel like being published in Nature meets the bar for actually being talked about on this forum. Maybe that means the talk is "this is a stretch, the peer review system sure failed there", but a) I think that's a fine bar and a fine conversation for this forum and b) I don't think this paper is one of those cases.
     
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