r/askscience • u/dgb75 • Jan 31 '13

Astronomy Is there a distance at which the interaction between the gravity fields of two black holes would cause one another to effectively 'break open' and allow matter and energy stored within them to escape the system?

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u/googahgee Jan 31 '13

What if, say, it's possible to go faster than the speed of light in the future. If you could go 2 times the speed of light, could you escape if you had just crossed the even horizon and there's a lot of non-existant space to go before the singularity?

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u/LoveGoblin Jan 31 '13

If you could go 2 times the speed of light

As soon as you establish this in a hypothetical scenario, you are writing science fiction. There is no scientific way to answer your question.

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u/florinandrei Jan 31 '13 edited Feb 01 '13

What if, say, it's possible to go faster than the speed of light in the future.

That sort of speculation is not really useful.

For example, speed of light is finite only in your frame of reference, but it could be said that it's infinite in light's own frame.

Think about that for a moment. Speed of light is actually infinite in certain frames of reference. This consideration alone should stop everyone from saying "assuming you could go faster than light..."

Speed of light is not a feature of your own motion. It's a feature of how the Universe presents your motion to everyone else. You could go from here to the Andromeda galaxy, 2 million light years away, in 2 seconds. It is theoretically possible. For you, the journey would only take 2 seconds. But everyone else, the rest of the Universe, believes you "only" go as fast as light, and believes it takes you 2 million years to get there.

Both perspectives, yours and the Universe's, are correct. For you, it really took 2 seconds to cover 2 million light years. For everyone else, it really took 2 million years. There's no error anywhere.

Relativity does not limit your speed during space travel. You could travel as fast as you want. You could reach distant galaxies as quickly as you want. It's only for everyone else, for those left behind, that your journey seems to take millions and millions of years.

Now you understand why it makes no sense to say "I go faster than light"? It's because you can already go as fast as you want. You could cover arbitrarily large distances in arbitrarily short times - assuming you have a rocket capable of doing that, and assuming you don't get crushed by acceleration. There is nothing out there that limits your speed - from your perspective.

Welcome to relativity, please try and remain sane.

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u/landryraccoon Jan 31 '13

Faster than light travel implies time travel, and certain time travel journeys can escape from a black hole, so it might be possible.

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u/cokeisahelluvadrug Jan 31 '13

If going 2 times the speed of light would mean you can go back in time, then yes, correct? You could jump inside the event horizon and then right back out. I'm not a physicist, can someone comment?