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Pharisaeus t1_jaobum7 wrote

> My basic understanding of orbital mechanics would suggest that this should be possible right?

No, because it would require the velocity to exceed the speed of light when you're approaching the periapsis. This is where the "classic" calculations fail. In "regular" orbital mechanics problem the closer to periapsis you are, the faster you're moving, and this way you "climb up" from the gravity well. However in reality there is a limit of how fast you can move, and in your example you'd have to exceed the speed of light in order to climb up from the gravity well after crossing the event horizon, and this is not possible.

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Quizznor t1_jaqg6rc wrote

> 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?

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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".

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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.

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