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Author Topic: The Weakness Of Gravity  (Read 9083 times)

Offline DerekT

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The Weakness Of Gravity
« on: 11/01/2008 16:20:26 »
We all know the problem. All the other forces (Electro magnetism, nuclear forces) are very strong but act over a short distance, whereas gravity is very weak but can act over enormous distances. Why is gravity different in nature from all the other forces?

Well here is my attempt at an explanation, feel free to laugh out loud.

Consider this thought experiment. You have a magnet, pretty strong but still small enough that you can carry it about. You have a ball bearing that is 10 metres away. Can you attract the ball bearing to the magnet? The answer is no, of course not, even though the magnetic field is strong, 10 metres is just too far away to have any effect.

Now imagine putting the ball bearing at the edge of a large trampoline and putting the magnet in the middle with the South Pole down. Crawl under the trampoline with another magnet north pole up and attract the top magnet to the bottom magnet using only the em force.

The trampoline deforms and sinks slightly in the middle, as a result the ball bearing rolls towards the middle and you have succeeded in attracting the ball bearing over a large distance using em. (I do understand that the weight of the first magnet would have deformed the trampoline but for the purposes of this thought experiment let's say that effect was negligible).

So have we really made em act over a large distance? Of course we haven't. What we have done is see an effect of em on the fabric of the trampoline. The ball bearing moving was a secondary symptom of this effect.

This is my theory about gravity. Gravity is the effect of a deformation in the fabric of space rather than a force in its own right. The force that causes this effect is (at present) invisible to us. It is the unseen magnet underneath the fabric of the trampoline with the opposite polarity to the visible magnet on this side of the fabric.

In this example it is the unseen object on the other side of the fabric of space with opposite properties to the visible object on this side of the fabric of space.

Even though it is unseen, however, it is very close, perhaps only fractions of a millimetre close and as such it is just like all the other forces, very strong and acting over a short distance.

I did tell you to feel free to laugh out loud :)

DerekT.


 

Offline HellFrozenOver

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The Weakness Of Gravity
« Reply #1 on: 14/01/2008 07:55:12 »
Well what i think is that gravity is a warping of space-time, but because of mass (the effects are only visible if it is very high density mass), rather than magnetic forces.. If it were magnetic forces what would the sources be? And as you said, the magnetic field would have to be relatively close in order for the magnetic field to have an effect..

Einstein was the one that proposed the idea of a rubber sheet and heavy objects deforming it, causing other objects to move inward..

Asyraaf
 

another_someone

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The Weakness Of Gravity
« Reply #2 on: 14/01/2008 10:50:20 »
You are wrong to say the effects of magnetism are short range (the effects of the Earth's magnetic field have an effect hundreds of miles into space).  Just like gravity, so too with electromagnetism (magnetism is merely a manifestation of electrical polarity), the actual range of the force in infinite, it is merely that whereas with gravity there is no opposite force (all gravity that we know of is additive, so if you put two objects that have a strong gravitational force close to each other, you get an even stronger gravitational force); conversely, with electrical (and magnetic) forces you have two types, which cancel each other out, so if you put something with a positive charge near something with a negative charge, the nett charge perceived at a distance is cancelled out.
 

Offline HellFrozenOver

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The Weakness Of Gravity
« Reply #3 on: 14/01/2008 17:38:20 »
If you use the example of the Earth's magnetic field, it is still relatively short in comparison with the size of the solar system. The space between Earth and Mars could be compared with the space between a magnet and a ball bearing bearing 10 meters away.

In theory any object with a mass would be able to exert gravity, its whether or not it is dense enough that the effects would be visible.

If gravity was the result of magnetic attraction, shouldn't we be able to counter the effects of gravity by reversing the polarity of the attractive force? Creating the possibility of anti-gravity rooms where the floor is the reverse polarity of the usual attractive magnetic force acting on us.
 

Offline Andrew K Fletcher

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The Weakness Of Gravity
« Reply #4 on: 16/01/2008 09:18:36 »
The moon counters the constant pull from the Earths Gravity and moves a huge volume of water  from one side of the planet to another. Yet we consider gravity to be a weak force?
 

Offline angst

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The Weakness Of Gravity
« Reply #5 on: 16/01/2008 14:45:41 »
Well what i think is that gravity is a warping of space-time, but because of mass (the effects are only visible if it is very high density mass), rather than magnetic forces.. If it were magnetic forces what would the sources be? And as you said, the magnetic field would have to be relatively close in order for the magnetic field to have an effect..

Einstein was the one that proposed the idea of a rubber sheet and heavy objects deforming it, causing other objects to move inward..

Asyraaf

Just had a thought. Would it be possible to 'measure' the 'elasticity' of space-time? And, is there an energy supply all around us? Is space-time under a form of tension?
 

Offline angst

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The Weakness Of Gravity
« Reply #6 on: 21/01/2008 22:43:15 »
Sorry to be a bore about this, but it is a serious question. If we see gravity as a facet of space time being stretched (like a 4-dimensional rubber sheet) then, that it distorts, and distorts proportionally to density and mass, would mean that space time is enacting a force upon that mass by holding it, by retaining it. It does not simply tear. So it must have a measurable 'elasticity', and it must have at least a potential energy in order to be distorted......am I making any sense?
 

Offline DerekT

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The Weakness Of Gravity
« Reply #7 on: 22/01/2008 22:57:12 »
Yes you are making sense, it is a question I have been asking for a while. I don't know if elasticity is the correct description but it certainly conveys the concept perfectly.

Why does space-time only deform as much as it does? What property of space-time is this? Can it be measured and what is the unit of measurement? I think it is an excellent question that deserves an answer. Sadly I'm not the man to answer it, but I shall read on with interest.

Oh and on the subject of gravity being the effect of another force, I am not suggesting that other force is magnetism. I am suggesting it is an unknown and unseen force from the other side of the space-time fabric. Maybe more akin to the strong nuclear force than magnetism, but probably something completely new. I just used the magnet on the trampoline as an example of the kind of thing that might be going on.

And on the subject of gravity weakness, all things are relative. My little fridge magnet can lift a paperclip off the table. It is a tiny magnet yet it is able to overcome gravity on the paperclip when the paperclip has the entire earth exerting gravitational attraction on it. Sounds pretty weak to me. Granted that at 250,000 miles the moon can still move water, so gravity is weak but far reaching :)
 

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The Weakness Of Gravity
« Reply #7 on: 22/01/2008 22:57:12 »

 

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