Submitted by Sol33t303 t3_11g1vky in askscience
Quizznor t1_jaqg6rc wrote
Reply to comment by Pharisaeus in Could we enter a stable orbit of a black hole which enters the even horizon and comes back out? by Sol33t303
> it would require the velocity to exceed the speed of light when you're approaching the periapsis
No! Once you pass the event horizon your worldline will terminate at the singularity. There is no way you would be able to exit the black hole, even with a hypothetical engine that provides infinite thrust.
Exiting the black hole is equivalent with going back in time. Approaching the singularity is equivalent with going forward in time. How do you accelerate away from tomorrow?
Lalaithion42 t1_jat9vmk wrote
An object traveling faster than the speed of light is going backwards in time in some frames, so there's not actually any disagreement between "going back in time" and "it would require the velocity to exceed the speed of light".
Quizznor t1_jav779k wrote
>An object traveling faster than the speed of light is going backwards in time in some frames
Where are you taking this information from? This "follows" from special relativity, where massive objects travel at strictly less than c.
Such statement don't have any physical meaning. You're braking the assumptions that were used to derive the equations you're relying on.
[deleted] t1_jaqlzt7 wrote
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