Cizuzj said:
This is not correct, and it gives people the wrong view. I.e. it makes people assume negative energy is a real thing, and not a consequence of how it is useful to use terms like negative energy to explain concepts, or to treat it as a short cut to simplify what you are attempting to calculate.
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As xkcd ones pointed out in a humoristic manner, it is certainly true that for complete correctness one would describe space-time as a set of equations, for which any analogy must be an approximation, but that isn't a very good read. So let's try to keep things as simple as the points we are trying to make allow it.
I don't see why you explain basics of quantum field theory in that explanation, since the rest of what you explain doesn't hinge on this analogy.
In any case, for what is relevant to the point the article makes you would rather call it "borrowed energy" then negative energy, yes? I usually see it referred to as negative energy in articles giving a basic explanation of the idea. And negative energy and borrowed energy is pretty much the same idea either way.
The relevant point is that a person inside the black hole wouldn't be exposed to energy equal to the hawking radiation, but would at most get energy from it taken equal to the energy emitted in hawking radiation (and the inescapability of the black hole is not violated in that).
Given that we are not extending this on any further physics models I would rather stick to the common terminology used in pop-science articles on the subject. Keeping it at familiar terms is easier on the reader.
There is no speed above the speed of light, and I wish it wasn't called the speed of light.
It is the speed of information itself.
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I'm aware of this and would find it cool for someone to bring it up, if it weren't irrelevant to the subject at hand. Fictional characters can go FTL, we have to deal with that fact.
A black hole isn't "pulling" space like a conveyor belt into the black hole, if you could go faster you could escape!
An analogy that is specifically avoided in the page in question, which is why it uses the light cone analogy instead.
No, even if there were FTL, you still couldn't escape a black hole.
The event horizon is special because it is the moment where everything flips. Just like the question, what's north of the north pole, what speed is faster than c, there is no outside to the event horizon.
But it get's even weirder then that.
Space itself at the event horizon becomes so distorted, all world lines lead to the singularity. This means space no longer leads out of the black hole. I.e. speed won't matter. Singularity beyond you and you walk away from it? You just walked towards it.
All directions of movement, any line you can draw, they all lead to the singularity. There is not a single line that can be drawn, that leads further away from the singularity.
Space itself is broken past the event horizon. It might as well be another universe completely, forever, and utterly cut off and inescapable once inside.
And at this point I have to actually disagree with the point you make.
Yes, after the event horizon all worldlines lead to the singularity. However, possible worldlines in these models are determined on the assumption that things don't go FTL.
As you yourself pointed out the speed of light as the speed of causality, so logically someone going FTL isn't directly bound by it.
I believe the antitelephone is a well known idea in regards to theoretical faster-than-light things. In other words moving into the past is a common consequence of FTL travel.
If you travel FTL you can leave your light cone, go to the past and by that take paths through spacetime that are usually not possible. Instead of just being able to move in spatial directions and forward in time at different rates, with FTL travel you could pretty much navigate time not unlike a spatial dimension (in the sense that you can move both forwards and backwards in it). In theory, you could use that to escape black holes.
Of course the entire premise violates science, which is why the idea only makes limited sense, but we can't exactly claim the opposite for a fiction were FTL movement exists.
