All Questions
Tagged with faster-than-light time-travel
37
questions
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Why Going Faster-Than-Light (FTL) Leads to Time Paradoxes? [duplicate]
In this video: https://www.youtube.com/watch?v=an0M-wcHw5A&lc=UgxqC71gefTRIuVubGt4AaABAg.9jI6ltMIeu59jx2P8cpn_z
In the video the following events happen:
A supernova goes off.
Earth sees the ...
- 2,706
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Why do we assume that we can change the past by sending signals backwards in time? [closed]
This might be a stupid question, but hang in with me-
From what I've seen, the biggest argument against superluminal signaling is that you would be able to send a message backwards in time that could ...
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Does the tachyonic antitelephone actually show a time-travel paradox? [duplicate]
The tachyonic antitelephone paradox is, roughly, this:
Alice is in a space station and watches Bob go past at relativistic speed in a spaceship. Some time later she sends him a message at ...
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Does travel through static wormhole(s) allow time-travel to the past? (Does one-way Tachyonic antitelephone compatible with reality?)
I'm trying to understand if faster-than-light travel via static wormholes is compatible with our current view of the Universe.
https://en.wikipedia.org/wiki/Tachyonic_antitelephone
gives two examples: ...
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3
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FTL travel without time travel (again)
In discussions about FTL communication and time travel, there is a simple thought experiment: the relativistic duel which is used to demonstrate that FTL travel implies time travel (I know it has a ...
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Could Gott's Cosmic String Time Machine hypothetically be used as a poor man's Alcubierre drive?
I have read much speculation about Gott's theoretical use of cosmic strings for time travel, but if the colliding cosmic strings accelerated the spacecraft faster than light, as Gott theorizes, could ...
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Why would an FTL-drive imply time travel? (other answers and questions unsatisfactory)
I've been spending quite some time trying to understand why an FTL-drive would also imply time-travel, but every answer I can find seems to mainly be about semantics and perception. I will break it ...
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Why does FTL imply that BACKWARDS time travel is possible? - Very Detailed! [closed]
I know this question has been asked before and I have read and understand the answers however imo none of them still imply that backward time travel is possible.
I understand moving forward in time ...
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Does non-local interepretations of quantum mechanics imply FTL communication? [closed]
For example the pilot wave theory... And if this is the case then does FTL commuincation imply time travel (i.e: information going back in time).
4
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Why would FTL imply time travel? [duplicate]
Edit:
Thank you all for the explanations, but I think until I fully grok special relativity, Lorentz transformations and relativity of simultaneity, the answers won't make any sense to me. Maybe the ...
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Is temporal causality broken by quantum entanglement?
When one particle of an entangled pair is measured, it forces the state of the other particle. This effect propagates faster than we can measure, certainly faster than light and possibly ...
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Need help understanding the argument that "faster than light motion does not imply time travel" [closed]
The paper in question is https://arxiv.org/abs/1407.2528 . But it contradicts known theory. Could someone ELI5? Is it legit? Are there any gotchas or catches?
Abstract
Seeing the many examples ...
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Question about the travel time of a ship "using" a warp drive metric
I - The Warp Drive metric:
The Warp Drive is a geometry in a spacetime $(\mathcal{M},g)$ given (in geometrized coordinates $c=G=1$) by the following metric tensor:
$$ ds^{2} = -dt^{2}+ (dx-v_{s}f(...
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Are tachyons time travelers?
If tachyons are faster than light, that means they have passed a certain point before anyone or anything can “see” them. Theories have mentioned that if anything can go faster than light, then it can ...
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Does time dilation mean that faster than light travel is backwards time travel? [duplicate]
Ok. So my question is, I've always heard it that Faster Than Light travel is supposedly backwards time travel.
However, the time dilation formula is
$$T=\frac{T_0}{\sqrt{1-v^2/c^2}}$$
And while it ...
