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A new theory of gravity?

  1. Yes

    1 vote(s)
    25.0%
  2. Maybe

    1 vote(s)
    25.0%
  3. No

    2 vote(s)
    50.0%
  1. Jul 13, 2009 #1
    I'm not a professional, I'm only hobby-physicist with a special interest in time and gravity. I have a theory that I've been working on, that I think is original. I thought I'd present the idea here to get some feedback.

    My theory states that gravity is not a fundamental force. It is instead a property of space-time to resist the warping caused my matter. I'm also convinced that this is why inertia exists. Space pushes all mater forcing it together (all in an attempt to reach a lower ground energy state); instead of mass pulling itself together.

    If I understand correctly, I believe that a theory such as this would make the standard model look real nice.

    Nightness
     
  2. jcsd
  3. Jul 13, 2009 #2
    I wouldn't call that new. In many ways that is what is being used at the moment. It is just not worded the same way. Or not enough different for me to be sure.
     
  4. Jul 13, 2009 #3
    "what is being used now at the moment"... Could you elaborate?

    Last I checked, it is commonly accepted that gravity is a property of matter, not space. And also considered one of four fundamental forces, indicating that a particle is the source of gravity.

    Nightness
     
    Last edited: Jul 13, 2009
  5. Jul 13, 2009 #4

    Hurkyl

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    Then your somewhat out of date -- Newtonian gravity has been supplanted by General Relativity. (The reason they still teach Newtonian gravity is that it's by far simpler, making it the best tool for the many applications where it's accurate enough)

    The central geometric idea is that of a manifold. First, think about the difference between a flat sheet of papr, and a sphere -- while we can use a flat sheet of paper to depict what's happening on the sphere (e.g. we can draw a map of the Earth), there are geometric differences between the two. Pay careful attention to the fact that a straight line (called a "geodesic") drawn on a sphere is a great circle, such as a line of longitude. (Lines of latitude are not straight on the sphere, despite the fact they often appear straight on maps)

    Have you fully grasped that? Now imagine the same thing in three dimensions instead of two. The geometry of physical space is different than Euclidean space geometry. While we may draw maps of the universe as if it were Euclidean, the actual geometry is different. In particular physically straight lines appear curved and bent in our three-dimensional map.

    Ok, now the really tough part -- and you probably have absolutely no chance to fully grasp this until after you've learned special relativity -- imagine the same thing in four dimensions: the actual 3+1-dimensional space-time we really (seem) to live in. Matter, when influenced by gravity alone, always moves in straight lines. However, if we try and draw flat Minkowski1 maps, such lines will appear bent. If we believe these maps, then gravity appears as a force.

    General relativity takes this picture as the basic geometry of the universe -- and the Einstein Field Equations specify how geometry and matter act to define how the geometry looks in the future. (And matter, when influenced only by gravity, always travels in the straight lines dictated by the geometry)



    That said, I don't think this resembles your idea at all. Have you managed to make any quantitative predictions with your ideas yet? Ideas are fine and stuff, but they aren't useful in physics until you can refine them to the point where you can actually make specific calculations. (and even then, we don't put any confidence in the idea until it's passed experimental tests) We use general relativity because it made some specific predictions that Newtonian gravity got wrong, and still gives the right answers in all the cases Newtonian gravity got right. And as we've probed deeper into the universe, we've found that what we see seems to continue to remain consistent with general relativity, thus giving us confidence that we can use it at such cosmological scales.
     
  6. Jul 13, 2009 #5
    Have you read about General Relativity? Do you know what that is?

    Matter warps space and time, forcing a straight line trajectory to become curved towards those objects.

    The particle version of gravity is iffy. Some Quantum-Gravity theories propose the existence of the graviton, but we have never found one.
     
  7. Jul 13, 2009 #6
    Yes I understand general and special relativity... I'm sure not nearly as well as either of you.

    So why is gravity still considered a "fundamental force"? (From wiki: fundamental force is a process by which elementary particles interact with each other").

    Also don't Einsteins field equations fail to explain the galaxy rotation curve?

    Nightness
     
  8. Jul 13, 2009 #7
    Galaxy rotation problem? Are you reffering to the question who's solution is the proposition of dark matter?

    According to Einstein, gravity is not really a force. But some theorists and apparently some people who write wiki articles believe there is a 'graviton' (gravity particle). Like I said, we haven't found one yet. We might, we might not, who knows...
     
  9. Jul 13, 2009 #8
    Also, if we look at your original post, you propose that space-time 'pushes' objects around. This isn't the case. Space-time is curved by objects, and the objects travel through curved space, giving them curved trajectories. So, space-time is more like a trampoline or bed sheet than a neighborhood bully, pushing things around : ).
     
  10. Jul 13, 2009 #9
    Not pushes objects around... Pushes objects together. Like pushing water bubbles together in a single-container (non-waveless) water bed, space is trying to "bubble-up" all the matter.

    I'm not disputing this.

    Edit: A trampoline has tension... If an object was layered between two trampolines (tightly pressed together), where would the object move to and end up resting (ignoring friction) because of this tension? The place where the forces on both the top and bottom of the object are weakest (the center in this case). I'm saying that space is a medium with a similar property; a property we call gravity.

    Nightness
     
    Last edited: Jul 13, 2009
  11. Jul 13, 2009 #10
    Yes... In my opinion Dark Matter is a cheap, even silly, way to make the equations, in an otherwise perfect theory, work. Dark matter has not been found in how many years of looking?

    Nightness
     
    Last edited: Jul 13, 2009
  12. Jul 13, 2009 #11
    The evidence for dark matter is the galaxy rotation problem. There is no better way to explain it, most are confident it's not a problem with Relativity.
     
  13. Jul 14, 2009 #12
    One, it doesn't matter whether you're pushing objects apart or together, direction is irrelevant. Spacetime does not 'push' objects anywhere. Spacetime is not touchable or observable with the naked eye or something.

    Two, again, spacetime is not exactly touchable. There is no 'tension' felt by objects simply sitting in spacetime. Spacetime does not 'press' down on objects or something.
     
  14. Jul 14, 2009 #13
    One pointer, you shouldn't critize things you're not familiar with. I'm not going to say I've never done the same thing before, but I can tell you that it helps to question something before you form an opinion about it.

    Dark matter isn't really 'found' in the sense that you're probably thinking. The best anyone can tell, it doesn't interact with light. So, we don't see it. But we can map where it should be because of bent spacetime and so forth, right. Google dark matter, there are maps of it all over.
     
  15. Jul 14, 2009 #14
    So you want me to "believe" (no real proof, so its a belief) in dark matter, but for some reason you can't conceive of a "tension" (gee inertia maybe?) in the "fabric" of space. You obviously did not understand my examples. Try thinking outside the box. Making up stuff (Dark Matter/Energy) to fit a theory, probably means the theory is not 100% correct.

    I invite others to support you, me, or just make their own comments... My discussion with you is one-sided (me talking to a wall).

    Thanks for the feedback, but I'd like to hear from others now.

    Thanks,
    Nightness
     
  16. Jul 14, 2009 #15

    Ich

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    That is, your understanding of mainstream physics comes from sloppily reading some popular books and watching tv? While you can't calculate a single problem using standard theories, it occurs to you that you have a pretty good understanding of these theories, and know all the important observational evidence and how it is interpreted?
    No, you don't have a http://en.wikipedia.org/wiki/Theory#Theories_in_physics".
    There are good reasons why this is not allowed here. There is a https://www.physicsforums.com/forumdisplay.php?f=146". Reading the rules there might help you to identify what you still have to do before you can talk about "your theory".
     
    Last edited by a moderator: Apr 24, 2017
  17. Jul 14, 2009 #16

    cristo

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    Please remember that personal theories are not permitted here at PF. I will leave this thread open, since it seems be to dealing with misconceptions at the moment, but if personal theories start being tossed around, this will be locked.
     
  18. Jul 14, 2009 #17
    Well thanks a lot. God, so childish. I was trying to help, I had nothing against you. You insist on being mean, FINE! good luck with your 'theory' mate!
     
  19. Jul 14, 2009 #18

    cristo

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    Ok, I hadn't read the post you quoted. With that sort of attitude, this thread is done.
     
  20. Jul 14, 2009 #19

    Integral

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    I have said this before, and will continue to repeat it.

    You cannot think outside of the box if you have no idea where the box is. Without a through understanding of modern Physics you cannot have even a concept of where the box is.
     
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