Explain to me how ergospheres don't allow effective faster than light travel...

Explain to me how ergospheres don't allow effective faster than light travel? The light cone is warped so that paths that would previously be considered spacelike (and therefore impossible) are now timelike, allowing particles to travel these paths at sub-luminal speeds. Can some user explain to me why this wouldn't allow you to actually travel faster than light as seen by a distant observer?

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Why are there two event horizons again?

Event Horizons don't exist.

Proofs?

You'd have to find a way of escaping the gravitational pull of the singularity in the first place, either by going brutally fast for a slingshot effect to occur, or by having strong enough engines to counter the said pull. That would need to be a small probe, which we can neither equip with such huge engines nor speed up so much with modern technology. So in practice it's an instant fail, to the best of my knowledge.

In theory, it could be possible, but for single molecules. Larger objects, like a human or a probe, would be stretched because of the heterogeneous gravitational field (side of probe away from the singularity and the one closer to it) and broken, read more on it here on Wikipedia under "Spaghettification".

So I guess we could send molecules like that, but I don't have any benefits from that, user.

It's not on an application level. By proving that sending even single atoms faster than light is possible you can eventually reach a conclusion that causality is wrong.

You can't travel faster than C through space, in the ergosphere you and the space you are in are all getting dragged around, you can use this to travel places faster than light would be able to if the ergosphere wasn't there, but because it is light can also use it and so will always travel faster than you anyway

Exactly. Light will still go faster than you in the egosphere. The egosphere also can't accelerate objects past light speed as they're coming out of it. At that point, it still takes infinite energy (which the black hole doesn't have) to accelerate to C .

For large black holes the event horizon is far away from regions with high gravity, so your problem would not occur.

Light still travels at c locally. Someone far away might see light travelling faster one way than the other, but relativity doesn't forbid that.

relativity literally means "light travels at c from all frames of reference" so no you're absolutely incorrect.

So how come this is allowed but when someone mentions a warp drive suddenly it is impossible because it would violate causality in some reference frame?

you might enjoy reading this: en.wikipedia.org/wiki/Penrose_process
It has to do with extracting energy from a rotating black hole, not moving faster than light, but it seems similar to your thinking.

You're thinking of special relativity.
General relativity say special relativity holds locally but necessarily globally.

>General relativity say special relativity holds locally but necessarily globally.
Should be "...locally but NOT necessarily globally".

'hj

Ergosphere is the result of space time actually moving to accomodate the speed of light?

I'm not sure if space can actually move

';l

God this board is stupid.

Do you have something to contribute?

nop

The universe doesn't give a shit about light. An egosphere is the result of a black hole spinning so fast that it pulls space around it.