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A comment on New type of black holes – Non interacting low-mass black hole. Parent comment

Re:New type of black holes – Non interacting low-mass black ... by vkou on Thursday October 31, 2019 @07:45PM (#21414979)
It can escape from a local 1G gravity if the black hole were as small as the Earth. As soon as you move 6400 km away, that 1G gravity turns into 0.25G.

But the event horizon of such a black hole would be far larger than that of the Earth. Move 6400 km away, and you'll still have a gravity of ~1G.

Rinse and repeat, and you'll find that even light won't be able to escape.

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Re:New type of black holes – Non interacting low-mass black ... by perl4ever on Thursday October 31, 2019 @07:50PM (#21415001)
The handy calculator says 1G at the event horizon implies a radius of half a light-year.
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Re:New type of black holes – Non interacting low-mass black ... by DuskStar on Thursday October 31, 2019 @08:01PM (#21415056)
Which means it'll be at 1/4G after you travel a further half light year.

That's a hell of a lot of energy. (If I'm doing the math right, the potential energy difference is on the order of ~20% of the rest mass at the event horizon)

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Re:New type of black holes – Non interacting low-mass black ... by gigatexal on Thursday October 31, 2019 @09:42PM (#21415596)
Yeah either the calculator is wrong or I don’t know what I’m talking about. Gravity at the surface of the black hole or the event horizon may well be 1G but all world lines point towards the singularity. I think what is missing is a sufficiently large black hole would have a really low average density at the event horizon thus you wouldn’t get speghettified instantly due to the huge discrepancy of gravity on different parts of your body.
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Re:New type of black holes – Non interacting low-mass black ... by deepsun on Friday November 01, 2019 @03:36AM (#21416876)
Yeah, black hole "radius" (not volume) grows linearly with it's mass. So very heavy black holes aren't that "dense".
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