The Long Pole Experiment

If I had a long rigid pole that was 10 million miles long straight up, could I send information much faster then light simply by pushing it up an inch? I’ve heard answers that since the pole can’t be rigid, it would warp and eventually slow the chain reaction down to below the speed of light. But it doesn’t seem intuitively true to me. What if the pole was frozen to absolute zero – can’t the constituent parts be completely flush, in theory, with no tork whatsoever? If constituent tiny forces or atoms can EVER be flush (and we know they can be, since they effect eachother) it follows that they can be in a continuous and prolonged state of flushness. Add to this the possibility of total rigidity, and you have a means to communicate data faster than light. Explain to me (slowly please) why this Rigid Pole Displacement Theory of Hypercommunication is wrong. Even if total rigidity is by definition impossible, perhaps we need only achieve a degree of rigidity that will outpace a quantum domino theory.


its certainly a very interesting question. Heres my understanding of why that wouldn’t work:

Atoms making up an object are not actually physically in contact. They are bound together by some kind of energy field. Or at least thats my understanding. When you move one atom, there is no way for the other atoms to know that it is their time to move until a fraction of time after the first one has moved. There will be a lag time between each atom. For it to be any other way, the atoms would have to be able to tell the future or be telepathic or something, so that they knew in advance that the other atom was about to move so they must prepare and be ready to move at exactly the same time. Also each atom must overcome its own inertia. So theres your answer, bearing in mind i haven’t studied physics since high school.

Marble, are you saying that the atoms would move in a “wave” pattern, where one “row” would “push” the next would push the next and so on?

This interests me, and I have little knowledge of this area.

marble is right,
the energy fields that would make one atom push forth the next, would travel at the speed of light…
on another note, if you had a iron bar of 10 million miles, the inertia would make it so that you would only make the close end of the stick shorter and the far end would remain at, more or less, the same position
of course this is more a practical matter, but still relevant

very sharp, marble

let me try to answer your questions, popy
the position of each particle has influence on the others, by which i mean that all particles generate forces onto eachother, electromagnetic bein the most important on this level…
i think it’s easiest when we look at a line of atoms

when one atom is accelerated, the information of the velocity change would spread through the universe at the speed of light
when this information reaches the next atom, the force on this atom changes, and it accelerates also

and on, and on…

that ok for you popy? or would you or anyone else like to know more
(i’ve studied some and this intrests me also, but i’m no expert…)


Glad you guys answered. I thought of this on my own after reading Ender’s Game and thinking about the Ansible. I’m sure it’s been brought up before but I’ve never seen it, so I’m very proud that I generated a thought experiment. I got D’s in science in high school. I love science. I just hate high school science. :wink:

In any case, we do seem to be dealing with some pretty fast info transfer and technically we don’t have to use any outside light/energy/electricity to make this speed occur other than a simple flick of the wrist. So in theory we have a form of near light speed communication that requires minimal energy and no electricity.

Further question. If I had a long rigid pole stretching from cleveland to newark, how fast would the communication be if I pushed it an inch (assuming the pole was in some sort of custom communication cradle on both sides). This would have to be morse code, but would this displacement travel at near light speed, assuming a titanium based alloy?

Furthermore, how fast does the back end of a titanium ball react when I begin spinning it from the front end, assuming a diameter of two inches. Would this be light speed data tranfer?

Also, when people suffer from chronic galloping pnuemonia or some other lung fluid emergency why not just cut open their chest and scrape off the goo manually. Seems like a big procedure, using a heart lung machine, but it sure beats dying.

the answer is, almost, because inertia would slow down the process…
inertia would also make it vey hard to move a rigid pole that reached from cleveland to newark, because of the incredible weight of the thing…

electricity is still more efficient, i think, Gamer
about yer other question, i’m no medic eh :stuck_out_tongue:


electircal signals passing over a phone line are just a long pole of electrons.

AC is like a long pole that’s being pulled back and forth 60 times per second.

Well it’s just good to know that if we had no electricity we still could communicate long distances, as long as we had the technology to create thousand mile metal poles rigid enough to not break but thin enough to move without twenty elephants. I won’t hold my breath for the Nobel prize.

You cant lift a 10 million mile long pole, your experiment is logically flawed.

obviously missing the point of the question…

it depends on gravity. I never said the endpoints would be within Earth’s atmosphere.

Well then, if gravity is 0 then you would have to pull back down on the pole to stop it at one inch, the inertia of the pole being pushed and the potential energy flowing towards the tip of the pole which is 10 million miles long, stopping it at one inch would be impossible.

But refferring to the point of your thread, something only happens as fast as you view it, and being ten million miles away, the movement of the pole would depend on the speed of the light reaching your eyes. energy moves at a rate of 186,000 m/s henceforth the amount of time it take s the chain of atoms to react to the kinetic energy from your ‘lever’, light has already reached the end of the pole. I may have got off topic, I kinda lost my train of thought lol.

i’d like to conduct a long pole experiment with your girlfriend!


(unless she’s ugly, then the long pole would be 10 ft. with a spike on the end)

It may not be light speed, but how fast is it, and how much energy is expended? I think it’s a fairly fast way to communicate long distances without electricity. Even if it was just five miles, the movement would be almost instantaneous, and without electricity. perhaps the pole could rest on top of liquid, it could float like a cork with a slick veneer to minimize drag.

imagine youve got a pole made out of nice steel that stretches to the horizon. imagine how much it weighs, and the gigantic machine that you would need to push it and how many pounds of pressure it needs.

now imagine, instead of the pole being really long, its 20 feet long and connected to a cube of iron that weighs as much as the rest of the pole would, just so you can see the effect on the pole scaled down to 20 ft.
so you smash it with the same amount of force. dont you see it crinkling up and totally just wilting under that pressure?

now say we someday find a way to synthesize diamonds and make them by the boatload and fuse them together well maybe that will work. i suspect that by then we will have found a much cooler way to do this

you see, we aren’t talking about actually doing it, we are talking about what if we did do it, what if we were strong enough, turn off the part of your brain that takes everything too literal.

:laughing: True, what if makes everything automatically true

I think instead of a pole, how about a really, really long spider thread five times as thick as a human hair attached to a bell a light year away which is kept completely taut. If you pulled the thread (in zero gravity, using a wench or whatever) how long would it take for the bell to ring? I wonder if it would travel faster then the speed of light maybe. It seems really backwards that a pulling force could travel forward. Not saying that it can’t, but it makes little sense to visualize it that way.