What would happen if you poked someone with a one light year-long stick?
This is an incredibly difficult question with an equally complicated answer. Looking past the obvious problems we’d face (how are we going to build a giant stick, for example), there are still numerous assumptions we’d have to make.
But, okay, let’s have a go. Let’s imagine that, hundreds of years in the future, humanity becomes so bored that they have nothing better to do than construct a giant stick in space with their newfangled and futuristic machines.
They send a human one light year away, out of the Solar System, and begin building a stick towards them. Once it’s built, someone on Earth (we’ll say this is a future version of you, with infinite strength) pushes the stick, which is an inch away from the person at the other end one light year away. Do they instantly feel the poke, thus receiving information faster than the speed of light?
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