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Author Topic: Is gravity a residual effect of nuclear forces?  (Read 2327 times)

Offline thedoc

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Is gravity a residual effect of nuclear forces?
« on: 21/12/2013 09:30:02 »
Casper Badenhorst asked the Naked Scientists:
   
I was wondering whether the actual cause of gravity is understood. I do know that the greater an object's mass is the greater the gravity it exerts on other objects.

I was wondering whether the gravity is not just a residual effect of the nuclear forces.

For example if it takes 99 units to hold an atom together but the nuclear force is 100 then that leaves 1 unit which can create an attractive force outside an atom. Now multiply that by more and more atoms with the object getting bigger and bigger, which would then result in a larger and larger objects having a greater and greater attraction from these residual units I mentioned above.

Kind regards

Casper Badenhorst

Sutton, Surrey

What do you think?
« Last Edit: 21/12/2013 09:30:02 by _system »


 

Offline Soul Surfer

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Re: Is gravity a residual effect of nuclear forces?
« Reply #1 on: 21/12/2013 11:51:50 »
There is a suggestion that gravity is a bit like the "van der walls"  forces that hold essentially electrically neutral atoms together in compounds but the main forces are operating in the curled up dimensions of string theory and not our normal dimensions of space and time.
 

Offline Pmb

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Re: Is gravity a residual effect of nuclear forces?
« Reply #2 on: 21/12/2013 20:44:15 »
Quote from: thedoc
I was wondering whether the actual cause of gravity is understood.
From the way you described what youíre looking for I can safely say no, itís not understood. However that doesnít mean that we canít fully describe it. In that sense we know a great deal about it. We just donít know the mechanism that causes one body to create a field which then exerts a force on another object. Science is all about describing nature. However we do want to know what the mechanism is. Thatís just never very forthcoming.

Quote from: thedoc
I do know that the greater an object's mass is the greater the gravity it exerts on other objects.
Yes. Thatís true. If the dimensions of the bodies are small compared to the distance between the bodies then the bodies can be described using the point approximation. In interstellar distances this approximation works out extremely well, especially since the sun and planets are basically spherical in shape. The Newtonian expression for the force on body one which has mass M and body two which has mass m is given by F = GMm/r2 where the force is attractive and r is the distance between the two bodies.

Quote from: thedoc
I was wondering whether the gravity is not just a residual effect of the nuclear forces.
No. It isnít. The gravitational force and the nuclear force are very different in nature. The former is a 1/r force, which is infinite in nature whereas the nuclear force drops off much faster and is limited in spatial extent, i.e. it falls off much much faster than the gravitational force and therefore does not have an infinite reach.

Quote from: thedoc
For example if it takes 99 units to hold an atom together but the nuclear force is 100 then that leaves 1 unit which can create an attractive force outside an atom.
I donít know what you mean by this. What is a ďunitĒ? Consider a hydrogen atom. It only takes two nucleons to hold it together. Then again look at Uranium 235. It contains 235 nucleons. The strong force exerted by a nucleon on other nucleons near it can only act on the ones that are touching it. It canít affect any other nucleons since its strength doesnít reach that far. The other force that acts between nucleons is the electric force and that dominates the gravitational force by many orders of magnitude and plays no role in holding the nucleus together unless the nucleus is so large as to be a neutron star.

I hope that helps! :)

Pete
 

Offline Phractality

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Re: Is gravity a residual effect of nuclear forces?
« Reply #3 on: 21/12/2013 21:19:10 »
It has occurred to me that gravity might be a tiny imbalance of much stronger equal and opposite the forces within massive particles. Perhaps the imbalance is caused by the expansion of space.
« Last Edit: 22/12/2013 02:08:21 by Phractality »
 

Offline Pmb

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Re: Is gravity a residual effect of nuclear forces?
« Reply #4 on: 22/12/2013 13:58:45 »
It has occurred to me that gravity might be a tiny imbalance of much stronger equal and opposite the forces within massive particles. Perhaps the imbalance is caused by the expansion of space.
There's nothing about gravity which would suggest such at thing.
 

Offline dlorde

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Re: Is gravity a residual effect of nuclear forces?
« Reply #5 on: 22/12/2013 16:30:03 »
It has occurred to me that gravity might be a tiny imbalance of much stronger equal and opposite the forces within massive particles. Perhaps the imbalance is caused by the expansion of space.
If the imbalance were caused by the expansion of space and that expansion is accelerating, that would suggest gravity becoming stronger over time. I don't think there's any evidence for this.
 

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Re: Is gravity a residual effect of nuclear forces?
« Reply #5 on: 22/12/2013 16:30:03 »

 

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