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Unexplained Nature

  1. May 1, 2004 #1
    We all know there are a lot of unexplained phenomenon out there - do you know some? I don't mean historical mysteries, UFO's, ESP, Miraculous Healing, etc ... I do mean things that can seen again and again e.g. I was told by a teacher that photosynthesis not fully explained yet, the flip of the magnetic poles of the earth (?), etc ...
     
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  3. May 1, 2004 #2

    Ivan Seeking

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    Although a lot of progress has been made in recent years, lightning still sparks many questions for atmospheric scientists. On a related note, ball lightning is now generally considered to be real but [mostly] unexplained.

    Dark matter, dark energy, and though many schools of thought are found that seek to resolve this issue, "the measurement problem" is still a core problem in physics; just to name a few.
     
  4. May 1, 2004 #3
    Didn't know that about lightning ... interesting.

    Whats "the measurement problem"? ... (If it's not too complicated) ...
     
  5. May 1, 2004 #4

    Ivan Seeking

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    It is complicated. In short, it turns out that the question of what exactly constitutes a measurement is now an 80 year old problem in physics. Do you know the old problem of Schrodinger's Cat from Quantum Mechanics?
     
  6. May 1, 2004 #5
    Erm...sounds familiar...think i read it somewhere ... forgot it

    What I'm surprised at is the lack of attention to unsolved mysteries ... or is it just me? (not being any sort of scientist) ... I guess its just that teachers are trying to get us to learn as much as possible before we start to explain mysteries

    ... But its fun ... :D
     
  7. May 1, 2004 #6

    Ivan Seeking

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    Until only recently insect flight could not be explained in some cases. The fact that bumble bee flight could not be exlained was once a favorite paradox to consider, many years ago.

    The mother of all unknowns in physics is physics. We can never know if physics produces a genuine description of nature [existence], that is to say a literal description of what's really "there", or if physics only produces models by which we can describe and accurately predict nature, but a description that in no way captures natures true essence.
     
    Last edited: May 1, 2004
  8. May 1, 2004 #7
    some things have been explained, but nobody listens to the explination. Old wives tales die hard.
    the bumble bee paradox is just such an example. "It is aerodynamically impossible for a bumble bee to fly." is ridiculous because we see them fly all the time. The original disscussion was about it being possible to build an airplane that flew the same way, or if a bumble bee was human size could it still fly.
    another one
    "Humans only use 20% of their brain." This is bull, we use all of our brains, just in different ways. If 100% of our neurons fired we would electrocute ourselves. Instead 20% of the neurons fire and 80% of the neurons insulate. Electrical cords only use the metal wires inside to carry electricity. No electricity is conducted in the plastic covering. Does that mean only 20% of a cord is used? Try stripping the plastic covering away and plug it into the wall.
     
  9. May 1, 2004 #8

    Ivan Seeking

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    I was not alluding to wives tales. The bumble bee problem was a problem of lift, weight, and power.
     
  10. May 1, 2004 #9

    Ivan Seeking

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    http://math.ucr.edu/home/baez/physics/General/open_questions.html
     
  11. May 1, 2004 #10

    Ivan Seeking

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    Freak waves

    http://news.bbc.co.uk/2/hi/science/nature/2450407.stm



    http://www.physicsweb.org/article/news/05/6/10
     
  12. May 1, 2004 #11

    Ivan Seeking

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    Last edited: May 1, 2004
  13. May 1, 2004 #12
    Sorry, Tribdog. 80% of neurons are not acting as insulation. Every neuron has its own insulation, the myelin sheath. It is the breakdown of this insulation that causes multiple sclerosis.

    Neurons don't conduct electrons like electrical wire. They are electrical in the sense that charges are moving but it is positively charged mineral ions that move, not electrons.
    There is no possibility of electrocuting ourselves or anything else with the action of neurons.
     
  14. May 2, 2004 #13
    The butterfly is also meant to be a mystery in flight (?) The last time I heard anything about this was when they found some super-springy mascle or something to that effect on the butterfly that can help explain it's massive wings...although I think it's still not fully explained.

    OK. What about this? Because we cannot predict - say, the shape of the water coming from a tap, does it mean it's still a mystery? ... jus a thot
     
  15. May 2, 2004 #14

    Ivan Seeking

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    I am a little fuzzy on the facts here so please forgive any potential misstatements, but I think that Chaos Theory tries to explain this problem of shape. I don't know that state of the explanation. I believe also that the point at which a nozzle discharge flow goes from laminar to chaotic is still undetermined; it cannot be theoretically predicted. What I mean, using the bathroom sink for example, is that if you turn on the water and slowly increase the flow, a point is reached where the flow turns from a smooth [laminar] to turbulent flow. The exact moment that this happens [as I remember] has no known solution.
     
  16. May 2, 2004 #15
    If I recall correctly from what I read in Chaos by James Gleick, the point at which this happens is repeatable in any given system. So, given the same pipe diameter, temperature, etc. it will happen at the same velocity each time. The mystery is non-repeating, unpredictable patterns of the turbulence that result. No one has been able to determine what variables account for this. It could, theoretically, be dependent on factors as small and unmeasurable as the exact position of every electron in every atom of the system when the turbulence starts.
     
  17. May 2, 2004 #16

    Ivan Seeking

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    You may be right; I read about all of this long ago in several sources including the one that you mention, but repeatable does not mean explained. What I remember was that no one has figured out a solution that predicts this moment.

    Edit: We can get a forced solution by using curve fitting techniques. This is not the same as having a model that explains the curve by using one or more of the conservation laws.
     
    Last edited: May 2, 2004
  18. May 2, 2004 #17
    I have to say. You know Much more than me on this - thanks for your input (I'll try and understand what you have said :D).
     
  19. May 2, 2004 #18

    selfAdjoint

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    There has been much recent progress on actual prediction. See this technical power point presentation on the 2003 Dirac Medal research. I don't believe they did the sink faucet problem but they did predict onset of turbulence in some interesting cases.
     
  20. May 3, 2004 #19

    Ivan Seeking

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    The shower curtain problem

    Another old favorite, this one was only recently solved.

    http://www.sciam.com/askexpert_question.cfm?articleID=0003302E-388B-1C71-84A9809EC588EF21
     
  21. May 3, 2004 #20
    I heard about the shower-curtain mystery. It's about time it got a proper explanation!
     
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