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  1. Standard member sonhouse
    Fast and Curious
    17 Feb '16 17:45
    Outside of evolution of life forms, it can also apply to rolling stones in a river to sand flowing down a sand dune and also living things:

    http://phys.org/news/2016-02-stones-turbulence-evolution-physics.html
  2. 18 Feb '16 08:36 / 3 edits
    I think what the link says is badly flawed because it isn't 'evolution' in the Darwinian sense of the word as it deviates far too much from that precise meaning and thus the word is used far too loosely here. For example, it says:

    Bejan also points out that rolling stones evolve to have less friction so that they can travel further. That is, they become rounder over time.


    yes but that isn't due to natural selection now, is it? It is because of them being worn down by impact and friction.
    In addition, they don't evolve via genetically inheritable mutations.

    I think it is important to distinguish and avoid confusion here between the more generic but vaguer English dictionary meaning of the word 'evolve' which means just 'change', not necessarily via Darwinian evolution, and the more specialized and specific meaning of the word 'evolve' as in change specifically via Darwinian evolution.


    In his previous work on animal size, lifespan and travel distance, Bejan also demonstrated that, despite their differences, all animals should have roughly the same number of breaths per lifetime. In much the same way, Bejan shows in his new work that, all other things being equal, all rolling stones and eddies have the same number of revolutions before their energy dissipates through friction.

    an arbitrary and irrelevant connection between the two things since, unlike animals, stones don't tend to have that property as a result of natural selection and genetically inheritable mutations thus this is not an indicator of 'evolution' in the same sense of the word.
  3. 18 Feb '16 09:49
    Ten years ago, Bejan developed a physical law called the constructal law, which states that any flowing system allowed to change freely over time will trend toward an easier flowing architecture.

    Seems like utter nonsense to me.
  4. 18 Feb '16 09:50
    "I'm defining evolution literally to mean what the word implies, which is continuous change in a discernible direction over time," said Bejan. "It's a movie. What Darwin imagined for animals and called 'evolution' is actually a physical description, and it applies to everything else that morphs freely while flowing, whether it's biological or not. So my 'aha' is that evolution is everything, because everything is in motion and is free to change while moving."

    His 'aha' moment was to realise things change over time? And this guy has a professorship?
  5. 18 Feb '16 09:55
    A law of physics explaining why larger animals live longer and travel further ...

    So swallows and bats must be enormous?

    And giant tortoises travel further than rabbits?
  6. 18 Feb '16 09:57 / 1 edit
    http://phys.org/news/2009-12-mystery-golden-ratio.html#nRlv

    He's a nutcase. Either that or the reporter is.
  7. Standard member sonhouse
    Fast and Curious
    18 Feb '16 13:37
    Originally posted by twhitehead
    http://phys.org/news/2009-12-mystery-golden-ratio.html#nRlv

    He's a nutcase. Either that or the reporter is.
    From the resistance seen here, he might be on to something
  8. 18 Feb '16 16:50 / 1 edit
    Originally posted by twhitehead

    His 'aha' moment was to realise things change over time? And this guy has a professorship?
    And then he arbitrarily, and I would say idiotically, labels that change as "evolution".
  9. Standard member DeepThought
    Losing the Thread
    19 Feb '16 10:25 / 3 edits
    Originally posted by humy
    I think what the link says is badly flawed because it isn't 'evolution' in the Darwinian sense of the word as it deviates far too much from that precise meaning and thus the word is used far too loosely here. For example, it says:

    [quote] Bejan also points out that rolling stones evolve to have less friction so that they can travel further. That is, they ...[text shortened]... nheritable mutations thus this is not an indicator of 'evolution' in the same sense of the word.
    Well, in Darwin's theory there is natural selection of features driven by the survival of the fittest. Darwin also has a hereditary principle. With stones in a river there may be features which persist for longer so one could argue that they are "fittest" but there is no hereditary principle - unless the system has some sort of feedback whereby the features which persist cause their configuration to be more strongly selected for. If he's arguing something like that then there may be some value.

    I saw a program ages ago where some researchers were designing a wing by making small adjustments to a row of something like twelve paddles roughly the shape of a feather and accepting changes that increased lift. After a while they had something that looked almost exactly like an eagle's wing.

    So I think that this is all quite reasonable. Bear in mind that these write ups are for a lay audience and are liable to omit essential parts of the argument. He wouldn't retain his position if his research was utterly ridiculous.
  10. 19 Feb '16 12:52 / 1 edit
    Originally posted by DeepThought
    If he's arguing something like that then there may be some value.
    Well no such argument is presented in the article.

    I saw a program ages ago where some researchers were designing a wing by making small adjustments to a row of something like twelve paddles roughly the shape of a feather and accepting changes that increased lift. After a while they had something that looked almost exactly like an eagle's wing.
    So they used a selection process. Not quite the same as biological evolution but certainly related.

    So I think that this is all quite reasonable.
    I don't see how that follows. The article in question has no significant similarities to the eagle wing example and does not provide any evidence of any selection process going on. The article instead takes the trouble to specifically state that a different definition of 'evolution' is being used.

    Bear in mind that these write ups are for a lay audience and are liable to omit essential parts of the argument. He wouldn't retain his position if his research was utterly ridiculous.
    I fully accept that the writer of the article may be at fault. I disagree that it is because it is 'for a lay audience'. More likely the writer didn't have a clue what he was writing about. However, I am not convinced that professors loose their position's for doing ridiculous research. Also I would expect the professor to take the trouble to ask for the articles about him to be removed if they do not accurately reflect his research. Is he perhaps not aware of them?
  11. Standard member vivify
    rain
    20 Feb '16 05:15
    Originally posted by sonhouse
    Outside of evolution of life forms, it can also apply to rolling stones in a river to sand flowing down a sand dune and also living things:

    http://phys.org/news/2016-02-stones-turbulence-evolution-physics.html
    Hasn't this Idea been around for decades? Isn't the universe believed to have evolved over time to what it is now from the Big Bang?
  12. Standard member DeepThought
    Losing the Thread
    20 Feb '16 05:36 / 1 edit
    Originally posted by vivify
    Hasn't this Idea been around for decades? Isn't the universe believed to have evolved over time to what it is now from the Big Bang?
    From the article Bejan seems to be arguing that there is something more going on in the systems he's interested in. Not only is there change over time, but the change is towards a configuration where the system finds the easiest route. Which is one of those obvious statements that's difficult to prove.
  13. 20 Feb '16 07:45
    Originally posted by DeepThought
    Which is one of those obvious statements that's difficult to prove.
    Actually its easy to disprove, as with some of the other claims in the article.
    When I wash dishes the plughole in my sink regularly gets gunked up - proving him wrong.
  14. 20 Feb '16 09:45 / 9 edits
    Originally posted by vivify
    Hasn't this Idea been around for decades? Isn't the universe believed to have evolved over time to what it is now from the Big Bang?
    The OP link says a lot of nonsense that has little to do with the universe 'evolving' over time. It just confuses the different meanings of the words 'evolve' or 'evolution ' esp the 'evolution' of living species via mutation and natural selection and the more generic 'evolution' as in mere 'change' of things, whether living or not, over time.

    In short, it makes the all too common error of equivocation.
    (In case anyone here doesn't know what that is, see:
    https://en.wikipedia.org/wiki/Equivocation )

    But it has occurred to me that Bejan just might have been massively misquoted by the editor and, if so, he really should do something about that starting with making a complaint here. The fact that he hasn't makes me guess that he was probability just talking nonsense just like the quotes in the link but I cannot be absolutely sure.
  15. Subscriber joe shmo
    Strange Egg
    20 Feb '16 15:22
    The "rock", for it to become a "rock", is an organized structure; distinct from other organizational structures. It had to be programatically selected to be that structure (based on the laws of physics as they pertain to the specific system in which it was initially organized). The question is: Does the "rock" want to programatically retain its "rock" structure when it is introduced to another system (like a river). If it does, then rounding, or smoothing of the rocks surface would be an advantageous selection response to being introduced to the changed physical system. Thus, changing its structure to a more hydrodynamic shape (again by the laws of physics) would enable the "rock" to remain a "rock" for longer periods of time.