Is gravity not actually a force? Forcing theory to meet experiments

Discussion in 'Physics' started by Dave, Apr 8, 2011.

  1. Dave

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  2. BillO

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    Good read.

    It deals with a discussion my brother and I have been having of late. He contends that the current scientific community is full of tin-foil-hat skeptics that are not willing to accept new ideas. Especially when confronted with 'fringe phenomenon'. From my perspective, this is simply not true. My point is that the researchers on the fringes tend not to follow the normal process. They present their cases without any regard for the 'as is' state of the science and provide little or no connective reasoning to allow other to follow from the 'as is' to the new theory.

    To Verlinde's credit, he has done a great job of providing that connection. His theory, rather fringe as it is, is therefore given some credibility. Enough that others started to check it out. Unfortunately he forgot about QM. Now I guess it's up to hi to patch that hole or see this interesting idea thrown on the bunk pile.

    Really neat concept though.
     
  3. magnet18

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    Very interesting, whether it is ultimately defeated or not.

    On a somewhat related note, I will be really surprised if there are any true field forces, on a small enough level it's probably particles causing the forces.
     
  4. mjhilger

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    I can see where you might come to the conclusion that fields are created by small particles, but then you have to explain why the particle interacts with another one, or why it has mass, or other observed effects. Then you get into the one question leads to another and down the rabbit hole. Fields exists and the quantum world is hard for us to imagine. This is because it tends to feel like something we understand like planets around the sun; then it breaks down and doesn't and does something completely different and confusing. The current theories using fields (some of which are known to be wrong) still provide the most close match to those observations. And with CERN we are smashing elements to determine the innerworkings with more energy than ever before, so maybe they will find better explanations.
    They have said using the accelerators is akin to throwing two pocket watches together and hoping to eventually to find all the individual parts which comprise the watch by the bits that fly apart. So the hope is that eventually enough energy is used to smash these things that the only surviving bits are indestructible. But some of these things are only produced when that much energy is used and they disappear very quickly. So then, how do you know if it is a fundamental component or a residual of the energy involved?
     
  5. mjhilger

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    After some thought, you can perform an experiment for yourself. It will not prove anything about fields, but it will prove that particles alone cannot be responsible for actions. Photons are fundamental particles as we understand them, and they are energy, but are massless. If particles were responsible for all actions, you should be able to take two lasers and have them intersect at 90 degrees. If particles were the underlying responsibility for the behavior, then you would expect to see at least some light (photons) shooting off at 135 degrees from either beam like a Y. This would be the result of a collision of particles. You can try this with light of any kind and it will not happen. You can use flashlights with white light (numerous wavelength within), monochromatic as in laser, or even set up a beam splitter and use the exact laser output (though the output here is not exact either, as the light is constrained within a small window of frequencies based on the optical cavity and its fluctuations, but some would be the same). No matter how you set it up, you will not see any shoot off as you would expect from mass, momentum (billiard balls).

    Again, while this does not prove that fields are at work, it should help you see that there is more than particles at play.
     
  6. magnet18

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    can massless particles even collide?
    shouldn't they have no inertia, or momentum?
    If they do collide, being waves also, couldn't they just have no energy at that moment (if the amplitudes are opposite) or double in energy for that moment (if the amplitudes are the same), or interact like waves?
    Who is to say that they are actually particles in the first place, or that they won't just pass through each other?
    What are the odds of them colliding anyway? How dense is light? What is the volume of a photon?
     
  7. nsaspook

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  8. mjhilger

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    That is the point, if all interactions were because of particle interactions, then you would expect to see something happen. It can't here! Again, this does not prove anything about fields being necessary, but you should see that particles alone cannot be the answer. Surprisingly photons do have momentum:
    [​IMG]h = planks constant, the lambda is wavelength, the h bar is h/2pi while k is wave number and the v looking character is frequency And p = momentumSo while it is massless, it conveys momentum.
     
  9. mjhilger

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    The gravity proposal is interesting. I like the end of the story where it explains how the author will probably eventually defend his work with a modified version to fit the quantum example. With the information age, ideas get passed around and get shot at instantly. Noting that previous ideas (hundred's of years ago) went through the same scrutiny, but with less fire as information traveled much slower. But this is the nature of the current defacto community. Then, every now and again, someone presents something with a lot of merit and we seem to catapult forward many steps (as in string theory) still dodging fire at the moment.
     
  10. BillO

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    @mjhilger.

    Your logic does not follow. Just because there is no interaction between beams of a specific type of particle, does not mean that particles are not responsible for all actions.

    There are different types of particles. Photons are mass-less bosons and hence will not interact with each other. Essentially your logic is saying that since bosons exist, particles cannot be responsible for all actions.

    In fact, photons are the exchange particle for the EM force.

    I am not saying that particles are responsible for all forces or actions, I'm just saying that your assertion holds no water.
     
  11. mjhilger

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    First I didn't mean to hijack the thread.

    The original statement by magnet18 was "On a somewhat related note, I will be really surprised if there are any true field forces, on a small enough level it's probably particles causing the forces." So my logic was that if ther are no fields, and particles are the only interactions at work, then all particles would have to interact with each other in some way. How would you explain their existance and creation if no other relationship was responsible except particle interaction? It quite possibily is flawed as you indicated. But the low level philosophy was that if no fields could exist, then all particles would need to interact with all others.
     
  12. nsaspook

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    I guess you could say that fields are "more" fundamental than particles because particles are the condensation of field energy. So on this level there could exist energy without matter but matter could only exist because of fields.

    But... it might be the other way around.

    [​IMG]
     
  13. magnet18

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    Energy has mass, and mass has energy. they are the same thing. There is no pure energy or mass, it just depends on the size of the object as to which it appears to be, with electrons being right on the line.
    So photons DO have mass, E=mc^2
    This thread is butting right up against the one about the EM radiation now.
    Also, I'm not against the idea that 2 particles could collide in ways we don't understand.

    Heck, our entire universe could be saturated with particles smaller than the Planck length and we would never know.
     
  14. nsaspook

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    The energy level for photons to create the mass to stop a laser beam from spreading is c5/G. About the energy of a supernova 10e52 watts. This is also about the same energy it takes to make a blackhole. It's also about the only place you could see photons with mass.
     
  15. magnet18

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    so they still have mass, it's just infinitesimally small, right?
    Just like all objects have wavelengths, they're just immeasurably small.
     
  16. Wendy

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    Sometimes people are uncomfortable with absolutes in numbers. I have had more than one person choke at the concept of 0Ω in a superconductor, and these were very experienced educated people. There are other examples out there all around. Current theory as I understand it is the singularity in a black hole is infinite density, it is part of what makes it a singularity.

    When I was studying the theory of relativity one of my favorite books was "The Universe and Dr. Einstein". It argued quite eloquently that photons had mass, and that several tons fell on a corn field every day. One of the arguments is they responded to acceleration and gravity pretty much the same way as conventional matter. Now I'm told it is massless. <shrug> OK, whatever.

    This concept explained solar sails to me quite well at the time.

    The same book argued that gravity and acceleration were aspects of the same thing. Put a person in a box on the surface of the earth, or accelerate them at 1G and there would be no experimental way of telling the difference without looking outside the box.

    One of the concepts presented in the first post is that we are a projection of something else, similar to a hologram. <shrug> OK, whatever. :D
     
  17. nsaspook

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  18. magnet18

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    I'm fine with absolute values like infinite density and superconductors, they make perfect sense. Superconductors actually have a different mechanism, electron pairing, so it makes sense.
    Divide by zero and you get infinity, divide by infinity and you get zero, makes sense to me.
    But mass and energy are the same, reduce mass and it behaves more like energy, and vica-versa.
     
  19. Wendy

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    The electron pairing mechanism does not work for high temperature superconductors. There are new mechanisms at work. The old metallic near absolute zero superconductors used Cooper Pairing.
     
  20. magnet18

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    Hmm...
    I'm not really up to speed on superconductor mechanisms, but Ill bet there is still a mechanism that allows it, and makes sense.
    And can photons even be at rest?
    And I still think it could just be an amount so small that is doesn't even matter at all.
    I'm not 100% sure since my background in math is lacking, but isn't the difference between an extremely large or small value of a limit an the absolute value that it should be essentially irrelevant in the result?
    [EDIT]
    If at rest, wouldn't it simply cease to exist?
    No mass or energy?
     
    Last edited: Apr 11, 2011
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