The discussion revolves around the hypothetical scenario of a one million light-year-long pole and whether Morse code signals could be transmitted instantaneously along it. The conversation explores concepts of compressibility, the speed of sound in materials, and the nature of wave transmission through physical objects.
Participants generally disagree on the premise of an incompressible pole and the implications for instantaneous communication. The discussion remains unresolved, with multiple competing views on the nature of wave transmission through materials.
Limitations include the assumption of an incompressible material, the dependence on the definitions of speed of sound, and the speculative nature of the scenario involving extreme lengths and conditions.
Any object when pulled stretches somewhat. With some materials this is obvious (rubber) with others it is less so (concrete). Whilst some objects are elastic and stretch a lot before breaking others are not and quickly break (if you were to pull at a brick it would stretch ever so minutely before it broke). So if you had a pole that was any length (whether it was between Earth and Mars or your left and right hand) when you pull one end it ripples all the way down it's length at its speed of sound stretching.
Imagine it this way, you have 100 people each standing in 100 one metre wide squares. These people have to remain the same distance between either neighbor preferably exactly 1 metre from the person on either side. If i take the person at one end and move them 1 metre then you will observe a ripple as one by one every one hops one metre to catch up with the person that just moved.
If the person at the other end can't move then the line is stretched with the ripple passing back and forth as everyone tries to both maintain an equal distance between each other as well as trying to obey the rule of being 1 metre away from both neighbours in this now 101 metre line of 100 people. If i was to let the end person jump back to his original place the ripple would travel down again.
The "ripple" speed in an object is the speed of sound within the object. It is impossible to build a magic string where all objects move at the same time to reposition themselves because it would require each atom to react instantly to what happens to every other atom.
Yes.mishrashubham said:I think this question should be added to the FAQ as it keeps coming up.