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What is gravity?

  1. Aug 14, 2004 #1


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    I don't know where to start, but I'd like to hear personal philosophies as well as accepted theories.
  2. jcsd
  3. Aug 14, 2004 #2
    For accepted theories I think you would have to go with Neuton as modified by Einstein's GR and SR. For off the wall stuff, I have a favorite, which I think is probably false but haven't yet been able to falsify. Backwoodsman's view explained more reasonably by myself. Basically it shows how electromagnetic radiation could be the source of gravity.

    Keep on chuggin !!

  4. Aug 14, 2004 #3
    The new forces and distances in closed system are related with the old like this:
    NewF= OldF cos - OldD sin and NewD = OldF sin + OldD cos
    This makes gravity.
    Gravity law is actually the law of lever.
  5. Aug 14, 2004 #4
    When all you have is a hammer, everything looks like a nail.

    Holds true with levers also :smile:

    Keep on chuggin !!

  6. Aug 14, 2004 #5
    Personal theory from my research desk:

    Gravity is proportional to the difference of electric force and magnetic force. The order of this difference is important. One order gives the ordinary attractive gravity and another the repulsive antigravity.

    The key to understanding why gravity can be attractive as well as repulsive is hidden inside the concept of vector product of two vectors. This makes the use of tensors not necessary.
    Last edited: Aug 14, 2004
  7. Aug 14, 2004 #6
    Sure; we can make positive and negative vectors as well as many other positive and negative things. How does that suggest that there is negative (anti) gravity? There is no observational evidence of such that I know of.

    Keep on chuggin !!

  8. Aug 14, 2004 #7
    The answer lies in the constant of proportionality. If this constant is zero then the physical effect is null. If the constant is small (like the the Planck's constant) then the effect is detectable. But the smallness can make the experimental process more difficult to carry out. And this smallness is inversely related to the energy used in the detection. The smaller it is the more energy is needed. To detect events at the domain of Planck length requires energy roughly [tex] 10^{19}[/tex] GeV.
  9. Aug 14, 2004 #8
    I see your point but don't quite agree. It's like excavating with a bull dozer. The bull dozer is faster but you can find lots more valuable stuff with a spoon and brush :smile:

  10. Aug 14, 2004 #9

    speed has nothing to do with any experimental process although all experimentalists at one time or another can be thinking to get it done quickly so to be home with the family. The scientific process is not an obligation, it is a search for the truth no matter how long it will take. But scientific refinement is very important.
  11. Aug 14, 2004 #10
    As an example for a case in point about refinement is the technological improvement from optical microscope to an electron microscope.

    Optical microscope can resolve small objects up to point when optical aberration starts to affect the quality of the resolution. So to see far more smaller objects requires the smaller wavelength of matter waves such as electrons which require more energy to maintain.
  12. Aug 14, 2004 #11
    My point was that when we smash particles with 10 billion dollar super-conducting super-colliders we make lots of noise, but when we collide electrons and positrons like at Cern, we get all the beauty of the universe unfolded in our lap. All of the real particles come out of the low-energy collisions. Super colliders give all kinds of short lived heavy stuff born of the energy of the collider itself.

  13. Aug 14, 2004 #12


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    This would fall under the "personal philosophies" category, rather than "accepted theories".

    I think that general relativity is well enough supported by evidence so that we can say with considerable confidence that gravitation is indeed a curvature of four dimensional space time. The question then becomes, "what is causing space time to curve?". Gravity is found in the proximity of mass and in correlation to the quantity of mass. This correlation is strong enough to lead the conclusion that there is a direct causal link between mass and gravity. I have an idea, which is not even developed enough to be given the name "theory", that the particles that make up massive objects in our four dimensional space time are actually cross-sections of hyper dimensional objects intersecting with our universe. Where these hyper dimensional entities make contact with, or "pass through" our dimension, they cause it to pucker, the way the surface of water curves around an object which penetrates the surface.

    Unfortunately, I am unable to imagine any way in which this concept of gravitation would make a prediction that is in any way at variance with any other model. Obviously, until a model or theory makes a prediction that is different from others, it cannot be tested.
    Last edited: Aug 15, 2004
  14. Aug 14, 2004 #13


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    You could say gravity is the check written by mass to pay it's conservation of energy debt. The negative energy of gravity offsets the positive energy of mass.
  15. Aug 15, 2004 #14
    Gravity is a monopole wave. Gravity is mass transference to it's lowest form of matter creating the actions of time and space and sychronization of matter.
    Last edited: Aug 15, 2004
  16. Aug 15, 2004 #15
    Can't make noise in a virtual machine.
  17. Aug 16, 2004 #16
    Your postulate is not philosophically sound. It does not hold that the reality of GR lends confidence to the idea of a curvature of four dimensional space time. One is an observed fact, the other is an attempt to explain the observations.

    Keep on chuggin !!

  18. Aug 16, 2004 #17
    I assume that for pure knowledge sake you might be interested in understanding the missing link, the evaporative gravitational wave. Spacetime is not the true way to understand the relationship between the concepts of matter, energy, time, space and speed. Relativity is the point of origin mass to energy transfer between matter, bound, and matter, free- the Gravity wave. That is to say that matter evaporates into the gravitational wave creating the actions of space, time and gravitational wave sychronization. Space is the gravitational wave being freed to its lowest form of matter. Time is the cosmological constant -the evaporation rate of matter. There is no real curved spacetime. It is gravitational wave sychronization, gravitational waves aligning through the path of least resistance that brings matter together, that is responsible time and space distortion as the waves elongate just as the dopler effect works in sounds. Instead of the sound wave being shortened or elongated when compared to moving objects the gravity wave is shortened or lengthened, red-blue shift which affects not the action of sound but the actions of time and space. Time and space are actions created by each discrete piece of matter as the matter evaporates into the gravitational wave. Space is the unfolding of matter. Time is the resulting action of the rate of evaporation of the gravitational wave. Relativity- Point of origin mass to energy transfer in wave form. That's Gravity! I appear to be ahead of the curve.
  19. Aug 16, 2004 #18


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    Most of the replies to this thread are codswallop.

    Gravity is the tendency of massive objects to attract one another. That's it.

    This tendency can be quantified and very precisely described. One must of course also define and quantify "massive objects". That's what you learn to do when you learn physics. If you want to learn physics, ignore all the other speculative stuff (gravity is photons, gravity is a monopole wave, gravity law is the law of the lever (sheesh)).
  20. Aug 16, 2004 #19


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    But the "reality of GR" to which you refer is the accuracy of its predictions, yes? The predictions are a result of the model, doesn't the accuracy of the predictions tend to support the accuracy of the model?
  21. Aug 16, 2004 #20
    That's the closest I've seen yet.

    Everything in the universe has an opposite (probably).

    Gravity is the opposite of Energy....

    All mass is comprised of energy and all mass has a gravitational field.
    Gravity adheres to the inverse square law in the same way that energy does.
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