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Old Jun 19th 2018, 09:01 AM   #11
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Let me suggest a scenario where perhaps causality gets hosed by Special Relativity (though I am not an expert on this to be sure - I'm sure someone smarter than I will point out an error in my thinking of there is one):

Suppose there is a very long, massless string connecting an astronaut floating is space to an object, such as a space probe, floating about 6000 miles away. The astronaut tugs on the string, and because his "tug" travels at the speed of sound in the string, let's say at 3000 miles/hr, about two hours later the probe "feels" the tug and is accelerated toward the astronaut. At least that's what the astronaut observes. Is it possible for an observer traveling at relativistic speed to observe the probe being accelerated before the astronaut tugs on the string?
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Old Jun 19th 2018, 09:28 AM   #12
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The answer is, quite simply, "no"! What reason do you have to think it could be otherwise?
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Old Jun 19th 2018, 12:31 PM   #13
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It will be because of material like this on Wikipedia:

"The interval AC in the diagram is 'space-like'; i.e., there is a frame of reference in which events A and C occur simultaneously, separated only in space. There are also frames in which A precedes C (as shown) and frames in which C precedes A".

Oddly enough this is incorrect:

"Therefore, if causality is to be preserved, one of the consequences of special relativity is that no information signal or material object can travel faster than light in vacuum".

The Andromeda paradox is incorrect too. There's a few things bandied around in relativity that people take for granted, but which but are something of a myth. My pet hate is the Penrose diagram:


Last edited by Farsight; Jun 19th 2018 at 12:33 PM.
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