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The Gravity Problem

  1. Jul 9, 2010 #1
    A few days ago I was thinking about Gravity and something hitted me.

    Is it possible that Gravity doesn't exist and in turn it's just an extension of the Strong Force?

    Gravity has always been extremely misunderstood in all of science, all it's known about it, is what it does, it pulls matter, but nobody really know what exactly it is!

    I started thinking about it when sometime ago I read some reports that in some experiments when scientists are able to cool matter down to absolute 0, Gravity seems to lose it's effect, this could indicate that Gravity is actually a byproduct of another fundamental force.

    Does this theory have some grounds in reality or is there something I'm missing?
  2. jcsd
  3. Jul 9, 2010 #2
    No they aren't.
  4. Jul 9, 2010 #3
    I'm talking about some experiments to cool down matter NEAR absolute 0 which made matter work like a superconductor and temporarly disabled gravity.

    But, is it possible that Gravity is actually merely an extension of the Strong Force?
  5. Jul 9, 2010 #4
    Hi Bruce, if I am not mistaken, you plan on modelling the gravitational force as the "unbalanced" part of the strong force between quarks in a nucleon, similar to interatomic (molecular) Wan der Waals forces arising from the imperfect cancellation of the Coulomb electrostatic force between the constituent particles of the two atoms (electrons and nuclei).

    If this was the core of your idea, let me tell you immediately that such a force actually exists. It is the "strong" nuclear force between the nucleons (protons and neutrons) and is responsible for holding the protons from not flying apart due to electrostatic repulsion. However, this force clearly does not have the same properties as the gravitational force:

    1) being proportional to the total mass of each of the objects;

    2) being inversely proportional to the square of the distance between the particles.

    The nuclear force is quite short ranged, becoming essentially zero beyond distances of the order 1 fm). The gravitational potential energy between two nucleons, each with mass nearly [itex]1 u = 1.66 \times 10^{-27} \, \mathrm{kg}[/itex] is:

    U = -G \, \frac{m_{1} \, m_{2}}{r} \tilde 10^{-30} \, \mathrm{eV}

    Compare this with the binding energy of [itex]2 \, \mathrm{MeV}[/itex] per nucleon. Thus the "strong" nuclear force is indeed strong compared to the gravitational force (and the other forces).
  6. Jul 9, 2010 #5
    Yes that was exactly what I was mentioning, thanks for your detailed description.

    My question here was the fact that what if the force doesn't become zero but unmeasureably weak after such distances?

    Gravity is known to be extremely weak, isn't it possible that IF the strong force manages to keep some unmeasured strenght on long distances, wouldn't the left over force have exactly the same effect that gravity has?

    As far as my knowledge goes, the more I read, the more I realize there is something terrible wrong with the concept and theories of gravitation.

    In my view the only way gravity could be properly explained is by being some resultant force of any or all of the other 3 fundamental forces.
  7. Jul 9, 2010 #6
    I think the current theoretical model for this strong nuclear force forbids it to fall of with 1/r2, just like the Wan der Waals forces, although originitaing from such a force (Coulomb), falls off much faster as 1/r6 (see multipole expansion).

    The problem is not in the strength of the nuclear force (which is much larger even between 2 protons) but with the rate of decrease, which limits its range.

    Another note. Your model predicts only baryon matter should interact gravitationally. How do you explain the deflection of light near massive objects then?
  8. Jul 9, 2010 #7
    Light, although not being baryonic matter it is electromagnetic radiation, by proposing that gravity is in fact a unknown extension of the strong nuclear force, some interaction could be expected that would explain the apparent workings of general relativity.

    I'm just proposing a view of gravity on a different direction, not to say that my proposition is absolutely accurate, but rather the point I'm trying to make is that when working with gravity, nothing really becomes accurate, something always fails when trying to describe gravity in a quantum reality.

    We know that the quantum world exists and we have proof of most particles and interactions predicted by quantum mechanics, so obviously it isn't quantum mechanics that is the problem, it is not known what causes gravity, the elusive graviton has never been found in any experiment and more and more complex theories are designed to try to explain gravity in a quantum universe.

    So it can be an equally valid statement to assume that there is no Gravity, only a gravitational "effect" that is caused by something we already know.
  9. Jul 9, 2010 #8
    This is not a satisfactory explanation. The strong force does not act on photons. How can any "extention" interact with photons? Then, it won't be a strong force anymore.
  10. Jul 9, 2010 #9
    Gravity is not temporarily disabled when you cool something near absolute zero. Why would you think that gravity is disabled?
  11. Jul 9, 2010 #10
    Because he had probably never taken a Classical Mechanics course and learned about equilibrium of forces.
  12. Jul 9, 2010 #11
    That's right I didn't, I have interest in deepen my knowledge on such issues, I have been studying particularly about gravity lately and there are many discrepencies and anomilies that I find mentioned in many places.

    The anomaly found with the Pioneer 10 and 11 spacecrafts which apparent are slowing down without any apparent reason, the flyby anomaly, the galaxy anomaly, in which stars farther away to the center of a galaxy seem to travel faster than expected.

    There are many insonstecies that general relativity cannot explain at the moment, I was making a speculative guess with my initial post, I now see that it was terribly flawed and I thank you people here for clearing me up in such issue.

    Still, can you please share your thoughts as to what you think is the cause with all these observational and mathematical inconsitecies and anomalies with gravity?
  13. Jul 10, 2010 #12

    disabled? or counteracted? There's a difference, and if what really happened was that gravity was disabled, that would be a bigger deal. Give more insights into it.

    As for gravity being a residual, I don't know. It doesn't seem that it could be a residual of the strong force, as it acts on particles that do not participate in the strong interaction (photons for example).

    However, we do not know what gravity is really, so it is possible that it could be a secondary effect of somethign else rather than an inherent property of its own. Actually, to me, this seems quite likely due to the fact that it is so weak compared to other interactions.
  14. Jul 10, 2010 #13
    No one in this thread had still acknowledged that gravity is not actually a force. Instead, there is gravitation - an effect caused by the curvature of space-time due to distribution of mass-energy.
  15. Jul 11, 2010 #14
    Yes, I understood the point you were trying to make, and I was making nothing more than non scientific guesses on my first posts, but still, I would like to know what are your thoughts on all the gravitation anomalies that I mentioned above that apparently violate what would be expected from general relativity.
  16. Jul 11, 2010 #15


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    Please read the https://www.physicsforums.com/showthread.php?t=414380". We have allowed this for a short period of time so that members can respond to why your premise is not correct. However, such speculation cannot continue, per the Rules that you had agreed to.

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