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howard2
2006-Jan-23, 10:18 AM
I was reading some of the lectures of the late great Dr. R.P.Feynman, and he emphasized the enormous force of attraction between two particles of sand 1mm across and 30 meters apart. If there was an imbalance in the quantity of electrons between the two. The force between them would be 3X10^6 tons. This astounding figure is used to emphasize the difference in the gravitational force and the electric force. So! maybe the local small scale gravitational effects are caused by slight electrical imbalances, and the larger scale, as in the collection of concentrated mass of electrical energy we call a planet. It has the effect of distorting The overall electromagnetic field we call the fabric of space time.
This mental image seems to fit with what I observe.
How does this mental image sound to you more educated guys?

Ken G
2006-Jan-23, 10:25 AM
Problem-- electrical forces can be either attractive or repulsive depending on the net charges of the two objects. But gravity is always observed to be attractive. Also, the ratio of charge to mass can vary, but gravity is always simply proportional to mass. It really is something different from electric force.

howard2
2006-Jan-23, 10:35 AM

howard2
2006-Jan-23, 11:26 AM
Maybe there is a slight bias in favor of an attractive force. It would only have to be very small. The electric force is 10^41 greater than gravity. The bias infavor of matter over anti-mater was very small and here we are. These tiny imbalances are what have allowed our universe to exist and evolve.
Does this make sense to you?

2006-Jan-23, 01:29 PM
....the late great Dr. R.P.Feynman, and he emphasized the enormous force of attraction between two particles of sand 1mm across and 30 meters apart. If there was an imbalance in the quantity of electrons between the two. The force between them would be 3X10^6 tons.Are you sure the units are correct? I'd expect a per unit area of some sort to apply or the masses to be totally ionic. How large a boulder does Feynman include in "a particle of sand"?

Ken G
2006-Jan-23, 03:51 PM
Maybe there is a slight bias in favor of an attractive force.
How do you figure? If you get gravity by setting the attraction of opposite charges to be slightly greater than the repulsion of like charges, you have to do something with the neutron, which has no charge yet neutrons pull on other neutrons via gravity (the Sun is neutron-poor, the Earth is neutron-rich, we could easily tell the difference). Stilll, maybe you could do something about this, like saying the neutron acts like a positive and negative charge together. It might be kind of an interesting idea, has anything been done with it?

Nereid
2006-Jan-23, 04:49 PM
Indeed something very like what howard2 seems to be asking about has been tested ... to quite a large number behind the negative sign which is the exponent of the number 10 ... and, as a bonus, these experiments also tested quite a few other possible imbalances, asymmetries, and possible ornerariness of gravity ... the E&#246;t-Wash Group page (http://www.npl.washington.edu/eotwash/) has some good summaries. Enjoy! :)

howard2
2006-Jan-23, 05:15 PM
Are you sure the units are correct? I'd expect a per unit area of some sort to apply or the masses to be totally ionic. How large a boulder does Feynman include in "a particle of sand"?

I Quote: Consider two grains of sand, a millimeter across, thirty meters apart. If the force between them were not balanced, if everything attracted everything else, instead of likes repelling, so that there was no cancellation, how much force would there be? There would be a force of of three million tons between the two.

Likes do repel, but if there is only a slight imbalance in favor of attraction, and it wouldn't have to be much to account for the localized attraction we call gravity. Maybe some of you mathematical types would like to figure it out? It just might work.

howard2
2006-Jan-23, 05:27 PM
Do you think that a sensitivity of 1X 10-12 of gravity is sufficient, when the electromotive force is 10^41 greater than gravity?

howard2
2006-Jan-23, 05:43 PM
How do you figure? If you get gravity by setting the attraction of opposite charges to be slightly greater than the repulsion of like charges, you have to do something with the neutron, which has no charge yet neutrons pull on other neutrons via gravity (the Sun is neutron-poor, the Earth is neutron-rich, we could easily tell the difference). Still, maybe you could do something about this, like saying the neutron acts like a positive and negative charge together. It might be kind of an interesting idea, has anything been done with it?

Well please correct me if I'm wrong but a neutron is equivalent to a proton with an electron crammed into it. Maybe it is not exactly electrically neutral? Maybe some are a little bit different. Say one part in 10^41?

korjik
2006-Jan-23, 07:02 PM
The main problem with what you are saying is that the electric field would be detectable if it were the cause of gravity. If you were sticking to the earth by coulomb force, you and the earth should have very specific electric fields. These fields are not detected.

2006-Jan-23, 07:58 PM
Stilll, maybe you could do something about this, like saying the neutron acts like a positive and negative charge together.
Isn't it? We "know" that a neutron has positive and negative charge because it has a magnetic moment, but the charges cancel. A neutron is said to be made up by one Up quark and two Down quarks (udd), where Up has +2/3 and Down -1/3 in charge.

howard2
2006-Jan-23, 10:26 PM
The main problem with what you are saying is that the electric field would be detectable if it were the cause of gravity. If you were sticking to the earth by coulomb force, you and the earth should have very specific electric fields. These fields are not detected.

Hmm! Please tell me how these tiny fields would be detected if they were to exist.

Nereid
2006-Jan-23, 11:00 PM
Hmm! Please tell me how these tiny fields would be detected if they were to exist.One method is by differencing - take two things that should be the same (according to standard ideas) but differ significantly in an aspect that you want to test. This is the basis of the Eöt-Wash tests (well, some of them).

Of course, you can't test for something as vague as 'these tiny fields'; you need to have a specific hypothesis. For example, an element that is neutron rich vs one that is neutron poor (the 'tiny charge', if unbalanced and on neutrons say, would add up to something quite significant).

howard2
2006-Jan-24, 12:45 AM
Yeah. That is what I am thinking, and that tiny charge may act as the attractive force we call gravity. But don't get me wrong, the neutron question was not proposed by me. I don't think it matters whether it is an imbalance in the EMF in protons or neutrons. The overall effect maybe an attractive force that we observe every day.
It needs someone much smarter than me to advance the concept in a mathematical form that can explore the posibilities.

korjik
2006-Jan-24, 02:31 AM
One method is by differencing - take two things that should be the same (according to standard ideas) but differ significantly in an aspect that you want to test. This is the basis of the E&#246;t-Wash tests (well, some of them).

Of course, you can't test for something as vague as 'these tiny fields'; you need to have a specific hypothesis. For example, an element that is neutron rich vs one that is neutron poor (the 'tiny charge', if unbalanced and on neutrons say, would add up to something quite significant).

I am not thinking tiny. If the force of gravity is EM, then the force keeping the earth in orbit isnt tiny, and that E field would be pretty obvious. The electric field is linear and additive. the 10^60 or so nucleons in the earth would add up to a big field.

Ken G
2006-Jan-24, 02:48 AM
It's not obvious that the electric field argument is actually a problem, as it is such a small imbalance in attraction vs. repulsion (not a charge imbalance between plus and minus, that would always yield repulsion). The point is, the whole concept of electric field would have to be altered, because the attraction would always have to be larger, on either type of charge. It would mean you'd have to know how much of each type of charge is present, not just the net charge. A lot would be different, but it's not obvious that it couldn't be made to work. I think the problem would be that a proton and an electron have a +1 charge and a -1 charge, for purposes of calculating the attraction and the repulsion, but a neutron has a +2/3 and a -2/3, as explained above. That would not give the same "gravity" from a neutron as from a proton + electron, and that is not correct. So the attraction coming from charges in a neutron would have to be even larger than that from charges in a proton or an electron. There would need to be some fine tuning of the theory, but it's not obvious you couldn't get Newtonian gravity. As for relativistic gravity, that might be pretty tough to do with electromagnetic forces, though I have heard of some effectively "magnetic" effects of gravity (perhaps frame dragging?). Someone might have looked at this idea already, from a theoretical standpoint. As for direct measurement, that might be hard to do, given the tiny difference needed.

papageno
2006-Jan-24, 01:54 PM
I think the problem would be that a proton and an electron have a +1 charge and a -1 charge, for purposes of calculating the attraction and the repulsion, but a neutron has a +2/3 and a -2/3, as explained above. That would not give the same "gravity" from a neutron as from a proton + electron, and that is not correct. So the attraction coming from charges in a neutron would have to be even larger than that from charges in a proton or an electron. There would need to be some fine tuning of the theory, but it's not obvious you couldn't get Newtonian gravity.
[...]
As for direct measurement, that might be hard to do, given the tiny difference needed. You could test it by doing experiments with a neutron-rich sample and a neutron-poor sample: simply use different isotopes of the same element, and the only difference would be the number of neutrons (and this can be done with current technology).
And since this difference could be 10^22 - 10^25, the effect would not be that tiny.

But these points have already been raised.

Ken G
2006-Jan-24, 02:29 PM
Actually, I think the problem would be that electrons and protons would feel an equal force of "gravity", and this would create a huge acceleration on electrons. Then electrons and protons would stay together under the action of gravity without the need for internal electric fields, called ambipolar fields, that in the real world are indeed generated to keep the fast electrons and the slow protons together under the action of gravity. So there's an observation that requires that the force of gravity on electrons be much smaller than that on protons, which tells you that gravity cannot be due to electric forces.

howard2
2006-Jan-24, 06:44 PM
Wow! I must admit that sounds like the nail in the coffin, but just a moment! there is something nagging me in the back of my mind. I'll have to come back to it later, after the parallel processors have churned over the latest input.

howard2
2006-Jan-27, 11:40 PM
Considering the randomness built into the universe. I don't agree that every electron and proton would have the same imbalance. The collective attractive force would be due to a sufficient imbalance. If it were possible to take 2 pieces of a substance and be sure that you had exactly the same number of atoms in each, it may be possible to see if they weigh exactly the same or not.
Can anybody do that?