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Forgive me if I'm thinking about black holes in completely the wrong way, but since time dilation increases to arbitrarily large amounts the closer you get to the event horizon of a black hole, wouldn't that make it impossible for anything to cross it, since it would require an infinite amount of time?

Is every single black hole in existence just an infinitely thin sphere of infinitely red-shifting matter around some kind of physics-breaking empty space that we'll never know anything about because it's impossible to get to? And if that's the case, does the "singularity" at the center of a black hole actually exist, or is it just a center of mass?

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You are wrong about the empty space part.

Sure you could make a black hole like that by taking a spherical shell of matter and letting it collapse around an empty space until it starts to get really close to the limiting event horizon.

But that's not normally how it happens. Normally you have something like a neutron star that already has matter in the inside, all the way down, even at the center.

So there is matter on the inside and the outside and every place in between. And there is a moment/event when the event horizon forms at the center and starts to rush out at the speed of light.

And that moment is a moment you don't see if you don't cross the horizon.

So you see the parts in the center from before that moment. And you see the parts on the outside from before the moment that expanding event horizon gets to them. And same with the parts in the middle, you see the moments before the event horizon got to those parts.

So you see every part of the star, you don't have a missing part. It is a frozen star or a red star. You see the center and the rest, but in very slow motion and very red shifted.

Now since the outer part of the neutron star blocked your view of the inside long before it formed a black whole, that is the reason you can't see the center. If you'd somehow put in a well with strong walls that let you see the center then you'd be able to look through it but it would be a slow and red view.

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  • $\begingroup$ Normal gravity (e.g. a sun or planet) curves space. Doesn't extreme gravity (e.g. a neutron star at the ctr of a black hole) condense/compress space? I imagine a BH is just like any other body in the universe--with the extreme exception that it has extreme gravity that sucks everything to itself that is within its gravitational field. I wonder, however, what conditions causes energy jets to be able to break free from its gravitational forces. $\endgroup$
    – DIYser
    Commented Dec 31, 2015 at 6:13
  • $\begingroup$ @DIYser Space isn't compressed. If you place a spherical shell of surface area $4\pi R^2$ around a star, no matter how dense or undense or extreme or negligible (as long as it doesn't have zero or negative energy) then you will have more than $4\pi R^3/3$ of volume inside. Gravity makes space larger, specifically a shell of regular matter creates more space behind as it collapses compared to how much closer it gets to the incoming material and this is a normal process of creating space as it creates the increased relative time dilation during the collapse. $\endgroup$
    – Timaeus
    Commented Dec 31, 2015 at 6:20
  • $\begingroup$ How do you arrive at that conclusion? As a massive sphere moves through space, it alters the space that it travels through, due to its mass, gravity, & gravitational forces. The space around that mass warps/curves. One side of a curve is compressed & the other is expanded along the curve. That seems to mean that space is flexible/modifiable by gravitational forces. It then returns back to its unaltered state as the spherical object moves along its orbit or other trajectory. Even a shell around a sun would have a lot of mass & gravity due to its size. $\endgroup$
    – DIYser
    Commented Jan 1, 2016 at 5:22
  • $\begingroup$ @DIYser I'm talking about the formation of large spacetime curvature. A star forms when matter collapses. When a spherical shell of matter collapses from a surface area $4\pi>R_1^2$ to one of surface area $4\pi R_2^2$ then the part outside the location stays the same and the part inside the new loocation stays the same and the part in between becomes larger. $\endgroup$
    – Timaeus
    Commented Jan 1, 2016 at 16:56
  • $\begingroup$ re "Gravity makes space larger, specifically a shell of regular matter creates more space behind as it collapses compared to how much closer it gets to the incoming material and this is a normal process of creating space as it creates the increased relative time dilation during the collapse." Where is the evidence that such a notion is true?? The concept of spacetime is fraught with logical defects, much like a person who actually thinks time=money because mankind sometimes equate $ in terms of time. Time is time & money is money. $\endgroup$
    – DIYser
    Commented Jan 1, 2016 at 18:18
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From what I know of black holes, you may get a few theories from this question, but the truth is we don't know presently. Singularities such as this are complete mysteries. We may never know, but as long as we survive our own self destruction, I believe we will figure it out eventually. :)

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