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Well in the quantum world of non- locality and entaglement atoms seem to know what others are doing on the other side of the universe at the exact same momentAlan
So if you had a pole stretching to the moon and then by your superpowers pushed it the movement traveling inside and outside (as seen from an observer) your pole would still be limited to 'c'.
QuoteSo if you had a pole stretching to the moon and then by your superpowers pushed it the movement traveling inside and outside (as seen from an observer) your pole would still be limited to 'c'.In this instance, if I read it correctly, it would be restricted to the speed of sound, wouldn't it?
Also, as predicted by special relativity, there isn't really any such thing as "instantaneous" over large distances. What separate (in space) events happen at the same time depends on your frame of reference.If I could send a signal to a distant object instantaneously in my reference frame, it would for someone traveling at a high velocity appear as me sending a signal back in time - which in turn leads to all kinds of paradoxes.
To make a thought experiment, imagine I could send a signal to a distant star which would arrive instantaneously according to my "resting" reference frame. The star then sends an instantaneous signal back (again instantaneous with respect to my resting frame) and I receive it at the same time that I send it. But if the star is instead traveling towards me and sends a signal back that is instantaneous according to its resting frame, I would receive the signal before I even sent it! This is because an event at my location which is simultaneous to an event at the distant star in my reference frame occurs after the event at the distant star in its reference frame (so that sending the signal back instantaneously in the stars reference frame would imply it getting back before it was sent). Cheers,-Emanuel
Einstein said that space and time really aren't the "absolutes" we imagine them to be. Simultaneity is also an illusion, said Einstein -- there's no such thing as universal 'now', because time passes at different rates depending on where you are in, say, a galactic gravity well, and how fast you're going. Two events can only be simultaneous if they happen at the exact same place and time. That's why you reset your watch when you pass a planet -- you can only be sure it's the same time if you're right there.There is however an "invariant spacetime INTERVAL" between any two events. Suppose you place two firecrackers in space a certain distance apart, set to go off ten seconds apart. To a stationary observer in the same frame, the interval between flashes is 10 seconds -- simple. In a moving observer's frame of reference, the time interval between flashes is distorted, plus the firecrackers have moved. Yet all observers, moving or not, get the same answer for the "invariant spacetime interval" between the two flashes -- square_root ( distance-squared minus time-difference-squared ), or sqrt ( x^2 + y^2 + z^2 - t^2 ). Yhat's just the Pythagorean formula for distance, but with a timelike component. In other words spacetime is real, but space and time separately are not. Space and time only SEEM separate if you're not moving -- if you are moving, space and time shift in a coordinated way, but invariant intervals remain constant. That's why you can use intervals as a measuring tool, such as the events generated by a bouncing beam of light hitting 2 mirrors.Invariant intervals between EVENTS are like the gold standard of special relativity -- they always work. The trick is to forget about the firecrackers themselves and just look at EVENTS that you know actually happened at a particular point in spacetime. Different observations of the same EVENTS can then be reconciled using the invariant interval. The only catch is that observers can't necessarily reconstruct a SEQUENCE of events, because in some frames of reference the 'wrong' firecracker goes off first.