2 ms·

This is kind of like Einstein's questions about cars on a train, or wondering what would happen if you were driving at the speed of light and turned on your hea

This is kind of like Einstein's questions about cars on a train, or wondering what would happen if you were driving at the speed of light and turned on your headlights. You might be tempted to think that if you are moving at the speed of light then you are moving just as fast as the light coming from your headlights, but you would be wrong. If you were moving at the speed of light and turned on your headlights, they would work just like normal headlights do on your normal car. (whether you could react in time to not be instantly obliterated and explode like a nuclear bomb is a different story) The speed of light is relative. For instance, nothing can go the speed of light as it would take infinite energy to cross the threshold from .9999999~9c and 1 c. However, parts of the universe appear to be moving away from each other faster than the speed of light, because the speed of light is relative to the observer. Point A and Point C are two separate observers so they have 2 separate frames of reference that must be accounted for even when you consider superluminal effects.

BizarroLand 5y ago
But let's go one further. Let's say that you have a computer program that knows the exact position and velocity of every particle in the universe and can with 100% accuracy know exactly where your target is in the universe regardless of distance at this very moment and the specific straight line between the two points. Your laser fires and the laser moves faster than the speed of light and instantly reaches its destination. Now what? At this point, the only way it makes sense to your frame of reference is to involve the laser itself duplicating and each of its duplicates traveling through time, one arriving at Point C and then moving backwards towards point A and one departing from Point A and moving backwards in time towards Point C. There would have to be some middle point B2 that is also at present relative time where the two duplicated laser beams meet and perfectly cancel each other out, and then a B1 and B3 where the same thing repeated, and so on down to the distance where some subsection of the plank length was so small that it was universally indistinguishable from 0. Which would mean that depending on your frame of reference the laser beam would have simultaneously erupted from and returned to every point along its line between point A and Point C, like a Math 126 Calculus problem brought into a horrifying reality, because it would most likely cause the destruction of a huge section of the universe by slicing a 20 light year wide 1 photon thick naked singularity into our galaxy, a.k.a jump starting the second big bang.

BizarroLand 5y ago

But let's go one further. Let's say that you have a computer program that knows the exact position and velocity of every particle in the universe and can with 100% accuracy know exactly where your target is in the universe regardless of distance at this very moment and the specific straight line between the two points. Your laser fires and the laser moves faster than the speed of light and instantly reaches its destination. Now what? At this point, the only way it makes sense to your frame of reference is to involve the laser itself duplicating and each of its duplicates traveling through time, one arriving at Point C and then moving backwards towards point A and one departing from Point A and moving backwards in time towards Point C. There would have to be some middle point B2 that is also at present relative time where the two duplicated laser beams meet and perfectly cancel each other out, and then a B1 and B3 where the same thing repeated, and so on down to the distance where some subsection of the plank length was so small that it was universally indistinguishable from 0. Which would mean that depending on your frame of reference the laser beam would have simultaneously erupted from and returned to every point along its line between point A and Point C, like a Math 126 Calculus problem brought into a horrifying reality, because it would most likely cause the destruction of a huge section of the universe by slicing a 20 light year wide 1 photon thick naked singularity into our galaxy, a.k.a jump starting the second big bang.