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Author Topic: How can we reconcile electromagnetism and gravity?  (Read 15987 times)

Offline jeffreyH

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It's all in the question.


 

Offline JohnDuffield

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Re: How can we reconcile electromagnetism and gravity?
« Reply #1 on: 23/09/2014 09:04:47 »
How can we reconcile electromagnetism and gravity? By reading original material by Einstein and Minkowski and others, and getting an intuitive understanding of how things work. For starters, see this piece where Einstein is talking about gravitational fields and electromagnetic fields: 

"Expanding the Theory
This theory having brought together the metric and gravitation would have been completely satisfactory of the world had only gravitational fields and no electro-magnetic fields. Not it is true that the latter can be included within the general theory of relativity by taking over and appropriately modifying Maxwell's equations of the electro-magnetic field, but they do not then appear like the gravitational fields as structural properties of the space - time continuum, but as logically independent constructions. The two types of field are causally linked in this theory, but still not fused to an identity. It can, however, scarcely be imagined that empty space has conditions or states of two essentially different kinds, and it is natural to suspect that this only appears to be so because the structure of the physical continuum is not completely described by the Riemannian metric."


See where he refers to a field as a state of space? OK, where an electron is, how many different states of space can there be? Answer: one. So the electron's electromagnetic field can't be something different to the electron's gravitational field. OK, next take a look at Minkowski’s Space and Time from 1908:

"In the description of the field caused by the electron itself, then it will appear that the division of the field into electric and magnetic forces is a relative one with respect to the time-axis assumed; the two forces considered together can most vividly be described by a certain analogy to the force-screw in mechanics; the analogy is, however, imperfect."

See how he talks about one field and two forces? If you have electrons and metal ions, the "electric" force between them is titanic. But if you contrive your electrons and metal ions as a current-in-a-wire, the "magnetic" force between two such wires is modest. Then when you stop the electrons moving, the force between the two wires is even more modest. And what do we call it? Gravitational force. See this thread where I gave a potted description of how gravity works. You need something similar for electromagnetism, and then you should see how they fit together. Of course, getting the maths to fit together is a different kettle of fish. 
 

Offline PmbPhy

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Re: How can we reconcile electromagnetism and gravity?
« Reply #2 on: 23/09/2014 15:30:13 »
Quote from: jeffreyH
It's all in the question.
Not really. I don't what you mean by reconciling them. Please tell me what that means to you. What would such a thing look like to you?
 

Offline Ethos_

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Re: How can we reconcile electromagnetism and gravity?
« Reply #3 on: 23/09/2014 16:50:44 »
Quote from: jeffreyH
It's all in the question.
Not really. I don't what you mean by reconciling them. Please tell me what that means to you. What would such a thing look like to you?
Maybe he's suggesting that, an as yet undiscovered formula, might be found that contains both G and e resulting in a proportional formula. If such an equation exists, it must satisfy all issues related to; mass, length, time, and energy and the said equation must also be balanced. This is something I've been trying to accomplish for many years and have had no complete success as we speak. While I've come close on occasion, I continue to be reminded of the old saying:

"Close" only counts in the game of Horseshoes!
« Last Edit: 23/09/2014 16:59:12 by Ethos_ »
 

Offline alancalverd

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Re: How can we reconcile electromagnetism and gravity?
« Reply #4 on: 23/09/2014 17:00:10 »
Why do we need to? Electromagnetism involves charge without mass, gravity involves mass without charge. You might as well reconcile fish and bicycles.
 

Offline jeffreyH

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Re: How can we reconcile electromagnetism and gravity?
« Reply #5 on: 23/09/2014 18:00:05 »
Why do we need to? Electromagnetism involves charge without mass, gravity involves mass without charge. You might as well reconcile fish and bicycles.

I think that sums up the situation quite nicely. I always wonder why we feel the need to relate them. I can't think of any reasonable way to do it. The proportionality constants don't match up in any way shape or form.
 

Offline UltimateTheory

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Re: How can we reconcile electromagnetism and gravity?
« Reply #6 on: 23/09/2014 18:03:41 »
The all massless particles have neutral 0e charge.

So far the only known particles with charge are the one with mass.

Formula relating charge with energy is known since XIX century:

1 C * 1 V = 1 J
« Last Edit: 23/09/2014 18:08:08 by UltimateTheory »
 

Offline jeffreyH

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Re: How can we reconcile electromagnetism and gravity?
« Reply #7 on: 23/09/2014 18:05:50 »
So we have a charged system and an uncharged system. The charged system involves the proton and the electron. The only uncharged system, as in canceling charges, involves the neutron. So is there a neutronic field?
 

Offline jeffreyH

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Re: How can we reconcile electromagnetism and gravity?
« Reply #8 on: 23/09/2014 18:11:33 »
When a mass collapses we end up in one case with a neutron star. Isn't this a big clue?
 

Offline JohnDuffield

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Re: How can we reconcile electromagnetism and gravity?
« Reply #9 on: 23/09/2014 18:13:30 »
Jeffrey: we say the electron has an electromagnetic field, and the proton has a an electromagnetic field. But put them together and step back, and we say the hydrogen atom has a gravitational field. Ditto for the neutron. It has a magnetic moment that betrays the existence of charge.

Why do we need to? Electromagnetism involves charge without mass, gravity involves mass without charge. You might as well reconcile fish and bicycles.
Because we are curious, and we want to know how the universe works. Electromagnetism doesn't just involve charge, a photon has no charge. Gravity doesn't just involve mass. A concentration of energy causes gravity, even when it's just a massless photon. You might not be interested in reconciling the two, but I am. As is my little friend below: 

« Last Edit: 23/09/2014 18:15:01 by JohnDuffield »
 

Offline UltimateTheory

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Re: How can we reconcile electromagnetism and gravity?
« Reply #10 on: 23/09/2014 18:14:01 »
There is dozen neutral particles.
Pion 0, Kaon 0 Short, Kaon 0 Long, to name a few.
You might say- they are unstable! But neutron is also not stable particle, with half-life ~10 minutes.
 

Offline UltimateTheory

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Re: How can we reconcile electromagnetism and gravity?
« Reply #11 on: 23/09/2014 18:18:00 »
Ditto for the neutron. It has a magnetic moment that betrays the existence of charge.

See isotopes with even quantity of protons and neutrons - they all have spin 0. And no magnetic moment. f.e. Helium-4.
Are they charge less just because of lack of magnetic moment.. ? No..
« Last Edit: 23/09/2014 18:23:40 by UltimateTheory »
 

Offline jeffreyH

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Re: How can we reconcile electromagnetism and gravity?
« Reply #12 on: 23/09/2014 19:15:21 »
OK. If we made up an artificial surface made up of segments of alternating north and south poles held firmly together in a box construction where would the flux lines in the centre of the surface go? What would the shape of this field look like if we plotted the field lines?
 

Offline JohnDuffield

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Re: How can we reconcile electromagnetism and gravity?
« Reply #13 on: 23/09/2014 20:37:18 »
UltimateTheory: agreed.

OK. If we made up an artificial surface made up of segments of alternating north and south poles held firmly together in a box construction where would the flux lines in the centre of the surface go? What would the shape of this field look like if we plotted the field lines?
We need to do it a bit differently and use photons. This is a depiction of a photon, which is a singleton electromagnetic wave. The upper portion gives the archetypal electromagnetic waveform. It's the derivative of the lower section, which shows four-potential.
 

Offline JohnDuffield

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Re: How can we reconcile electromagnetism and gravity?
« Reply #14 on: 23/09/2014 20:52:23 »
When you have a whole array of photons close together, the field ends up looking like this:
 

Offline JohnDuffield

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Re: How can we reconcile electromagnetism and gravity?
« Reply #15 on: 23/09/2014 20:55:51 »
You may have seen something a bit like this before: 


GNUFDL image by Johnstone, see Wikipedia 

Note that the "rubber sheet" depiction of gravity is actually back to front. A better analogy would be a block of gin-clear silicone rubber with a "pressure" in the middle pushing out.
 

Offline jeffreyH

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Re: How can we reconcile electromagnetism and gravity?
« Reply #16 on: 23/09/2014 21:41:12 »
When you have a whole array of photons close together, the field ends up looking like this:

So what are you saying the consequences of this are?
 

Offline JohnDuffield

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Re: How can we reconcile electromagnetism and gravity?
« Reply #17 on: 23/09/2014 22:22:25 »
So what are you saying the consequences of this are?
The gravitational field is what you're left with when electromagnetic fields largely cancel one another out. 
 

Offline alancalverd

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Re: How can we reconcile electromagnetism and gravity?
« Reply #18 on: 23/09/2014 22:32:16 »
The magnetic field produced by an electric current is independent of the mass of the charge carriers. A 1 amp proton, electron or ion beam has exactly the same magnetic field as a 1 amp current flowing in a copper (electron conductor) or aluminum (hole conductor) wire.

If you oscillate the current you will generate electromagnetic radiation, the frequency and intensity of which are dependent only on the frequency of oscillation and the rms current respectively, and have nothing to do with the mass of the charge carriers.     

Thus gravitation and electromagnetism are unrelated.
« Last Edit: 23/09/2014 22:35:19 by alancalverd »
 

Offline jeffreyH

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Re: How can we reconcile electromagnetism and gravity?
« Reply #19 on: 23/09/2014 22:36:58 »
The magnetic field produced by an electric current is independent of the mass of the charge carriers. A 1 amp proton, electron or ion beam has exactly the same magnetic field as a 1 amp current flowing in a copper (electron conductor) or aluminum (hole conductor) wire.

If you oscillate the current you will generate electromagnetic radiation, the frequency and intensity of which are dependent only on the frequency of oscillation and the rms current respectively, and have nothing to do with the mass of the charge carriers.   

Which brings us back to the surface with alternating poles. I would still like an answer to where the field lines go. Where does the circulation go? How does this limit the extent of the field. Is there any cancellation?
 

Offline jeffreyH

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Re: How can we reconcile electromagnetism and gravity?
« Reply #20 on: 23/09/2014 22:43:24 »
I concur. I can see no relationship between them. I have tried to find one. Thought and thought and thought some more. It is annoying that the equations look similar (constant times value over distance squared) and yet they are poles apart. Pun intended.
 

Offline Mad Mark

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Re: How can we reconcile electromagnetism and gravity?
« Reply #21 on: 24/09/2014 00:01:14 »
I think before we get to reconcile electromagnetism and gravity we need a far greater understanding of the fundamental particles/energies that make up space-time
and possibly technology that can delve deeper into the atom and make predictions and test theories on what fundamental particles/waves make up a Quark.
 

Offline jeffreyH

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Re: How can we reconcile electromagnetism and gravity?
« Reply #22 on: 24/09/2014 03:15:05 »
Let's think about the UV catastrophe and Planck's quantization of energy, angular momentum etc. If we think of spacetime itself as quantized and the energy released from the electron to only fit neatly into this quatized spacetime it's only option is to move at one speed. If there is a compression of the quantization of spacetime, making it a smaller and denser medium this will ultimately affect light accordingly. Now mass is said to cause this effect. What is it about the mass that can cause such an effect. We have charge which is independent of mass. The electron is smaller than the proton but both have the same charge. We have gravitation which is dependent on mass. Is it though? Can gravity itself be like charge and change in strength with the density of that mass. Like the observer getting the wrong speed from his gravitational constant when viewing a companion nearing a black hole are we missing this vital point? As the gravity changes with density this would increase the curvature os the spacetime around it. Also it could aid the compression of the mass until at a critical point it collapses in due to a dual system of compression. One compression of mass and another separate compression of spacetime. If these are proportional to each other we just have to find this proportionality. It may lie in the theory that the density of black holes lowers with mass increase. This could be counter balanced by an increasing spacetime density.
 

Offline alancalverd

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Re: How can we reconcile electromagnetism and gravity?
« Reply #23 on: 24/09/2014 06:27:01 »
If we think of ..... the energy released from the electron

And there's your problem. Electrons don't release energy.
 

Offline PmbPhy

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Re: How can we reconcile electromagnetism and gravity?
« Reply #24 on: 24/09/2014 08:08:28 »
Quote from: alancalverd
And there's your problem. Electrons don't release energy.
They do carry kinetic energy when they move but I assume that you're referring to an electron at rest emitted photons. Is that correct?
 

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Re: How can we reconcile electromagnetism and gravity?
« Reply #24 on: 24/09/2014 08:08:28 »

 

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