Thought Experiment I recently had

Hmm quite an interesting thought. That's just like the thought about what is the universe supposebly expanding on. I guess my input would have to be that nothing would really have to go faster than the speed of light because all the molecules are linked, which would make it instant anyways. No different than pushing a bar that makes you 3 feet apart.

Originally posted by DaRAGE
It allt he particles are stuck together with no strathc, bend, no other way to move...then it owuld happen as just mentioned above. If u had 2 bars opposite eahc other and moved them back and forward to discern thema s binary... 1's and 0'1, then u would be sending a signal across space faster than the speed of light...

Thats the thing, the atoms inside the material are not 'stuck together with no stetch or bend' they are only held in place by electromagnetic forces. Forces that propogate at the speed of light. Moving one end does not immediately move the other. It takes time for each atom to shift across and push the next one out of place, this takes an incredibly short period of time. But the time adds up as we make the object longer and longer.

Well put Kano,

we were assuming that this steel bar had infinite rigidity (at least I was) and therefore would behave the way that browha had postulated.

-Durandal

Yes, but the problem with the theory of an infinitely rigid object is that the internal forces would have to act instantaneously. Thus we'd know of forces that travel faster than the speed of light anyway, and not have to make a long bar

infinite rigidy? that seems like a pretty impossible material, but just say the it is possible, im still sure that the bar would 'flex' or 'ripple' as the forces holding it together (EM) are @ the speed of light. (also the scissors are quite similar as you could just imagine them as the two bars closing in on each other.

its like those little swinging balls, as the end one falls it appears to instantly travel through the others and make the end one swing up.



Also about gravity, is gravity the attarcting force between any type of matter? or is it emitted if you get what i mean? Because lets say that the universe ends with one big huge black hole, there is nothing outside the black hole to affect, so would it still have gravity?

Thats a very good point Kano.

way to use the noggin.

-Durandal

Originally posted by browha
Imagine a long bar of steel, several billion kilometres long, in space.
Imagine that there was absolutely 0% stretch when a force is exerted on it.
If you were holding one side of it and I was holding the other, and I pulled on my side, you would feel the pull instantly on yours..
This is potentially over a region that would take light a recordable time to pass...
So the signal is travelling faster than light..
Right?

Feel free to rip it apart etc I would just like to know feed back

I know I'm late to the fray, but...

Wouldn't it be instantaneous?

Originally posted by Cappa
I know I'm late to the fray, but...

Wouldn't it be instantaneous?

No.

When you are late to the fray it sometimes helps to read all the previous responses.