I need somebody knowledgeable in physics

[Gandalf_The_Grey]

So I have a little quandary that's been on my mind (on and off) for a good while now, hoping somebody can explain this.

Now as we all know, the speed of light is currently considered the "universal speed limit", the fastest matter or energy can travel. So we'll keep that in mind.

So, imagine that I have an iron bar (we'll just take away gravity for convenience) that's so long, it stretches from one end of the galaxy to the other. By this I mean the longest end to the other longest end, which if I remember correctly is 20,000 lightyears.

So here's this 20,000 LY long bar in space. Suppose I grab one end and push it to the side, it should make the other end move in unison like any other bar, right? But for that to happen, I'd have to apply energy at one end, and have a reaction from that energy occure at the other. This means that energy applied at one point can somehow travel to the other, 20,000X faster than the speed of light which should be impossible.

So how could this work? If no energy can travel faster than light, how does energy instantaneously travel 20,000 Light Years?

Gandalf_The_Grey Reviewed by Gandalf_The_Grey on 07-14-2007. I need somebody knowledgeable in physics So I have a little quandary that's been on my mind (on and off) for a good while now, hoping somebody can explain this. Now as we all know, the speed of light is currently considered the "universal speed limit", the fastest matter or energy can travel. So we'll keep that in mind. So, imagine that I have an iron bar (we'll just take away gravity for convenience) that's so long, it stretches from one end of the galaxy to the other. By this I mean the longest end to the other longest end, Rating: 5

[anomalousirrelivance]

relativity my friend. time is not the same time on the other end of that pole. very good thinking tho, you are outside of the box which is the best way anyone can be.

i dont know how to explain it in detail but you would never be able to communicate that far instantaneously so i would be hard.

quantum physics seeks to explain however, how one subatomic particle after coming in contacts with another particle will communicate as though there was no distance in between no matter how far the distance really is.

[Gandalf_The_Grey]

relativity my friend. time is not the same time on the other end of that pole. very good thinking tho, you are outside of the box which is the best way anyone can be.

i dont know how to explain it in detail but you would never be able to communicate that far instantaneously so i would be hard.

quantum physics seeks to explain however, how one subatomic particle after coming in contacts with another particle will communicate as though there was no distance in between no matter how far the distance really is.

I kind of see what you mean. Relativity and quantum theory have always interested me, but I'm sure my understanding is relatively (no pun intended) amateur.

But what you said reminds me of how my friend, a physics major, explained how electrical current doesn't actually travel. How there's already a current from one end of the wire to the other, and the "traveling charge" is just one charged particle energizing the next that's in contact with it. Actually that's probably a poor explanation, but I'm tired, stoned, and it's been quite a while since I last discussed this.

I really like your quantum theory on it though. I know we haven't gone into any detail yet, but I've been learning about how things are linked at the quantum level, how multiple particles from the same source, separated by thousands (or any amount) of miles, will be affected at the same time in the same way if just one of those particles is affected.
I think this is why a lot of buddhists (including myself) really like quantum theory, because it tends to jive with the buddhist theory that consciousness, while an impermanent set of multiple complex processes, has a certain "essence" to it, created by it, that at the smallest level is connected with all other consciousnesses, and can bind to other consciousnesses upon death (due to samsara-driven karma). Ah but I digress, gettin' high always makes me go off on tangents.

And please, by all means, anybody feel free to help me out with my super-long iron bar problem!

[Raelum]

in a sense you are correct, this is pretty much what the super string theory is.

basically replace your iron bars with strings of gravity, and since ALL gravity effects ALL matter in the universe simultaneously, you could theoretically move a string and it will instantaneously move the part of the string billions of light years away.

at our current level of technology we dont have any way to manipulate gravity.

heres some more info on the theory, Superstring theory - Wikipedia, the free encyclopedia

i would also suggest reading "the elegant universe" but some chemistry and physics background will help alot

a theory about gravity, the one i choose to believe
"Gravity Dimension" - Gravity; faster than the speed of light!

hope this helps,
Raelum

[home.grower]

Interesting topic, but it has been discussed in places that atoms can communicate with each other infinite distances with time not being a factor.

[Coelho]

Well... about the problem of the iron bar:
When you push the bar, you are not pushing the bar as a whole. You are only actually pushing the atoms of it which are in contact with your hand. This atoms will then push their neighbors, their neighbors will push their own neighbors, and so...
The "pushing" that the atoms will do in their neighbor atoms travels trough the entire bar, like a wave, until its end. Look at the picture i did... the first line is the atoms of the bar, and in the second, 3rd, 4th, lines is what happens when you push it. Note that the end of the bar only moves in the last line, when the "pull" of the atoms reach there.
And the speed of this "pull" is not even the speed of the light, but the speed of the sound in that material. In case of iron, it some 3 miles/second.
The fact that the pull goes with the speed of the sound is very reasonable, if you remember that the sound is just the "pull" of the molecules in the air, and the sound actually is just a mechanical pertubation, a mechanical wave, through air, or steel , or whatever.
I hope my explanation is clear enough. If not, feel free to ask! :thumbsup:



EDIT: i cant resist to say that we really dont need to use quantum physics, relativity or strings theory to understand a wave travelling through a bar... its classical physics.

[420ultimatesmokage]

^^good reply, i was going to respond something similar to this but i think you covered it all quite nicely

[Raelum]

^^good reply, i was going to respond something similar to this but i think you covered it all quite nicely

seconded

[Coelho]

^^good reply, i was going to respond something similar to this but i think you covered it all quite nicely

seconded

Thank you both! :thumbsup:
Anyway... im a physics teacher, so it was almost a duty to answer him...

[420ultimatesmokage]

Thank you both! :thumbsup:
Anyway... im a physics teacher, so it was almost a duty to answer him...

glad to see a cool pot smokin physics teacher :jointsmile: