Timeline for One of the consequences of travelling faster than light [closed]
Current License: CC BY-SA 4.0
18 events
| when toggle format | what | by | license | comment | |
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| Oct 8 at 0:14 | comment | added | Dale | @SolomonSlow said “if faster than c means anything different from faster than light, then there must be circumstances under which the speed of light is not c”. Yes. In non-inertial frames the speed of light is not necessarily c, in both special and general relativity. That is precisely the point I am making with that wording, so I am glad that it is understandable | |
| Oct 7 at 22:40 | comment | added | Hug de Roda | Just a comment to reflect on: How is this non mainstream physics if this is taught in college? I also provided my mathematical reasoning and I didn't spit random non-sense or personal theories... Is it that hard to ask something relativity related and be received well in this forum? Thank you too, @James, I already kind of knew the limitations of SR like in the twin paradox; I didn't think about it in this case though. | |
| Oct 7 at 22:06 | history | closed |
Jon Custer Miyase Matt Hanson |
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| Oct 7 at 18:24 | vote | accept | Hug de Roda | ||
| Oct 7 at 14:35 | review | Close votes | |||
| Oct 7 at 22:06 | |||||
| Oct 7 at 11:55 | comment | added | Dale | @RootGroves KDP is correct. You are still missing the distinction between “faster than c” and “faster than light”. Also, the river model is very limited | |
| Oct 7 at 11:21 | comment | added | Root Groves | @KDP no the escape velocity at the event horizon is c which means spacetime is falling inside the black hole at a rate of c. | |
| Oct 7 at 11:09 | answer | added | Eric Smith | timeline score: 1 | |
| Oct 7 at 8:14 | comment | added | KDP | @RootGroves Nothing travels faster than light relative to particles (inertial or otherwise) in the local vicinity, not even when falling into a black hole. Nothing can overtake a light particle in the local vicinity. | |
| Oct 7 at 2:14 | comment | added | Dale | @RootGroves it is even easier than that. Just turn in a circle and any stars you see are travelling faster than $c$ in your frame. No need for a black hole or event horizon. But note that the question isn't about faster than $c$, it is about faster than light. Nothing does that whether you are spinning or falling through an event horizon | |
| Oct 7 at 1:16 | history | edited | Qmechanic♦ |
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| Oct 7 at 0:54 | comment | added | controlgroup | Everything breaks down when you try and follow spacelike curves. For the cause you describe to have the effect you describe, some intermediary object would have to follow such a curve, which means that causality is broken as usual. | |
| Oct 6 at 23:26 | comment | added | James | @ Hug de Roda I believe analysis of causality using SR is limited... Light paths are not straight and can be bent in GR. It is easy to mess around with causality using bent light paths, e.g. signal A happens before signal B. But signal A gets rerouted by a passing black hole. Signal B (because it is sent later in time) is not rerouted by the black hole. Thus signal B arrives before A for a distant observer. SR analysis seems of limited usefulness for complicated analysis like causality, because of assumption of no acceleration, straight light paths, etc... | |
| Oct 6 at 21:58 | comment | added | mmesser314 | I think you mean the case when $U=c$. See A photon travels in a vacuum from A to B to C. From the point of view of the photon, are A, B, and C at the same location in space and time? | |
| Oct 6 at 21:22 | comment | added | Root Groves | tac objects past the event horizon have a velocity greater than c towards the center of the black hole. | |
| Oct 6 at 21:19 | comment | added | tac | It's impossible to travel faster than light, you would need an infinite amount of work to accelerate the particle up to that speed. Second, the delta notation introduces interval between events, so you are implicitly talking about two events. The change of sign means that the sequence of events can be inverted between the reference frames. | |
| Oct 6 at 21:03 | comment | added | Root Groves | But traveling at a speed more than c is very easy , just fall in a black hole!If we could somehow extract information from the falling observer I think it would help us solve faster than speed of light paradoxes. | |
| Oct 6 at 20:48 | history | asked | Hug de Roda | CC BY-SA 4.0 |