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A comment on Neutron stars may be bigger than expected, measurement of lead nucleus suggests. Parent comment

Re:Neutron stars may be bigger than expected, measurement of... by colechristensen on Tuesday April 27, 2021 @09:27PM (#26964288)
>As you fall from the event horizon to the singularity, you see the entire future of the universe unfold since all arrows of time now point toward the singularity so as you move along it, you are moving in time.

This would suggest that as I see the entire future of the universe as I fall towards the event horizon I also see the entire future of the horizon itself... which means that I will never cross the horizon because it will at some point far in the future no longer exist.

i.e. there is no spacetime path which ever crosses the event horizon

I'm near the point where I'm going to have to learn some black hole math to convince myself otherwise. (I think I'm wrong but can't see why)

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Re:Neutron stars may be bigger than expected, measurement of... by hoten on Wednesday April 28, 2021 @12:37AM (#26965647)
Relevant discussion: https://physics.stackexchange.com/a/79086

> i.e. there is no spacetime path which ever crosses the event horizon

As I understand it, there isn't, from the perspective of an observer external to the event horizon.

(warning: I am only an avid watcher of PBS Spacetime)

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Re:Neutron stars may be bigger than expected, measurement of... by pdonis on Wednesday April 28, 2021 @12:52AM (#26965734)
> As I understand it, there isn't, from the perspective of an observer external to the event horizon.

This is not correct. An observer outside the horizon cannot see anything at or inside the horizon; but that doesn't mean he can't calculate that there is a region of spacetime inside the horizon, from observations he can make from the outside. He can.

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Re:Neutron stars may be bigger than expected, measurement of... by colechristensen on Wednesday April 28, 2021 @02:35AM (#26966383)
As I understand it at this point... there is no round trip spacetime path to the horizon and back and best-case light which hits (or is arbitrarily close to hitting the event horizon) can get back to you the moment the black hole finally evaporates. However the first half of that trip is possible and happens in finite time.
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