Magnetic attraction

[Gawdzilla Sama]

The lines of force idea works in the motors around you. Better theory is awaited.

[Xamonas Chegwé]

The electromagnetic force is much greater than the force of gravity - by 36 orders of magnitude - ie. it is 1,000,000,000,000,000,000,000,000,000,000,000,000 times stronger!

Both are infinite in extent and decrease in strength inversely proportional to the square of distance.

I'm not arguing, but, for the sake of discussion, can they actually be infinite in extent?
Just going on the often repeated mantra that there are no actual infinites.

From a quantum point of view, I can see a situation where a gravitational effect drops to such a low level, that it can't achieve the minimum quantum effect needed to progress any further.
Same with electromagnetic force. Pure guesswork on my part, but it would reconcile the impossibility of an actual infinity.

I see your point. You are basically saying that once the source of gravity waves (assuming they exist - but that's another discussion!) are so far away that they warp local spacetime less than the Planck length in any direction, they might as well not be having any effect, and that there is therefore a maximum effective range.

This idea has merit (as far as my knowledge extends anyway) but, since gravity is cumulative and directly proportional to mass, increasing the mass of whatever was causing the gravitational effect would increase that effective range proportionately - so, if your argument is valid and such a limit exists, its theoretical maximum would depend on the total mass of the universe. The question then becomes one of whether the effective range of the gravity caused by the total mass of the universe is greater than the volume of the universe. It is also possible that gravity is compposed of particles (gravitons) which could have an infinite range but perhaps not observable effects beyond a particular point. Fucked if I know!

With electromagnetism, the range is clearly infinite (or unbounded if you prefer) - there is no real difference (except in wavelength) between a magnetic forcefield and light - both are propogated by photons.

[Xamonas Chegwé]

The lines of force idea works in the motors around you. Better theory is awaited.

Better theory is QED - Quantum Electrodynamics - the most accurately tested scientific theory ever!

[macdoc]

http://twistedsifter.com/2012/05/visual ... n-filings/

[mistermack]

I suppose that anything that is propagated at a finite speed, e.g. the speed of light, cannot ever be infinite in extent. You would need an infinity of time for that to happen.
It's all really just potential infinities, that can never occur in reality.

With a single photon being indivisible, it has the potential to travel for ever. But it needs the fabric of space to travel, so if space is not infinite, nor is the travel of energy.

The quantum vacuum is not empty. Can energy travel through emptiness, or does emptiness actually exist?

[JimC]

The electromagnetic force is much greater than the force of gravity - by 36 orders of magnitude - ie. it is 1,000,000,000,000,000,000,000,000,000,000,000,000 times stronger!

Both are infinite in extent and decrease in strength inversely proportional to the square of distance.

I'm not arguing, but, for the sake of discussion, can they actually be infinite in extent?
Just going on the often repeated mantra that there are no actual infinites.

From a quantum point of view, I can see a situation where a gravitational effect drops to such a low level, that it can't achieve the minimum quantum effect needed to progress any further.
Same with electromagnetic force. Pure guesswork on my part, but it would reconcile the impossibility of an actual infinity.

I think this is an interesting point, which should at least apply to electromagnetic interactions.

However, if we take the classical view of general relativity, gravity is the result of mass/energy warping space-time, and the warping effect should have no boundaries. If there is a contradiction here, it reflects the current inability of physics to reconcile general relativity with the quantum realm...

[mistermack]

It really depends on how these effects are propagated, and transmitted.
If space is warped in an infinitely smooth manner, you would think the effect could be potentially infinite. But if it happens in minute steps, like one domino knocking over another, then you might get a point where theres not enough ooomph to topple the last domino.

If that were the case, the effect should be reflected back the way it came. Maybe it might be possible to detect something like that one day.

[Tyrannical]

Insane Clown Posse did a hilarious version of Slim Shady. If you've never heard it................

[hackenslash]

I'm not arguing, but, for the sake of discussion, can they actually be infinite in extent?

Certainly. The problem here lies in precisely what is meant by 'infinite'.

Just going on the often repeated mantra that there are no actual infinites.

Well, like most truisms, this one probably isn't actually true.

https://webspace.utexas.edu/deverj/pers ... worlds.pdf

[Pensioner]

Is that why hitler did not like the Poles

[Pensioner]

The electromagnetic force is much greater than the force of gravity - by 36 orders of magnitude - ie. it is 1,000,000,000,000,000,000,000,000,000,000,000,000 times stronger!

Both are infinite in extent and decrease in strength inversely proportional to the square of distance.

I'm not arguing, but, for the sake of discussion, can they actually be infinite in extent?
Just going on the often repeated mantra that there are no actual infinites.

From a quantum point of view, I can see a situation where a gravitational effect drops to such a low level, that it can't achieve the minimum quantum effect needed to progress any further.
Same with electromagnetic force. Pure guesswork on my part, but it would reconcile the impossibility of an actual infinity.

I see your point. You are basically saying that once the source of gravity waves (assuming they exist - but that's another discussion!) are so far away that they warp local spacetime less than the Planck length in any direction, they might as well not be having any effect, and that there is therefore a maximum effective range.

This idea has merit (as far as my knowledge extends anyway) but, since gravity is cumulative and directly proportional to mass, increasing the mass of whatever was causing the gravitational effect would increase that effective range proportionately - so, if your argument is valid and such a limit exists, its theoretical maximum would depend on the total mass of the universe. The question then becomes one of whether the effective range of the gravity caused by the total mass of the universe is greater than the volume of the universe. It is also possible that gravity is compposed of particles (gravitons) which could have an infinite range but perhaps not observable effects beyond a particular point. Fucked if I know!

With electromagnetism, the range is clearly infinite (or unbounded if you prefer) - there is no real difference (except in wavelength) between a magnetic forcefield and light - both are propogated by photons.

Fuck off XC, you make my brain hurt.