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[Beeskee]

The mass does matter, it's what determines where the event horizon is. Everything has an Schwarzschild radius, just that for everything we have can interact with, the mass is mostly outside that radius. The only reason a singularity is infinitely dense is because it's squeezed by gravity, which has overcome every other force by that point.

Think of it this way: a 10 solar mass star doesn't collapse into a black hole until it runs out of fuel. It loses some mass when it goes bang but collapses into a black hole once the fusion reactions that were constantly pushing against gravity cease. But all the mass to make a black hole was already there, it just wasn't squeezed small enough to make a black hole.  The space the mass is condensed into is what determines whether it is a black hole or not. A single grain of sand could be made into a black hole, if you crushed it down smaller than the smallest thing we know of.

[ECrownofFire]

The mass does matter, it's what determines where the event horizon is. Everything has an event horizon, just that for everything we have can interact with, the mass is mostly outside that horizon. The only reason a singularity is infinitely dense is because it's squeezed by gravity, which has overcome every other force by that point.

Think of it this way: a 10 solar mass star doesn't collapse into a black hole until it runs out of fuel. It loses some mass when it goes bang but collapses into a black hole once the fusion reactions that were constantly pushing against gravity cease. But all the mass to make a black hole was already there, it just wasn't squeezed small enough to make a black hole.  The space the mass is condensed into is what determines whether it is a black hole or not. A single grain of sand could be made into a black hole, if you crushed it down smaller than the smallest thing we know of.

There is a limit to that though, at some point the Schwarzschild Radius is going to be too small to actually exist.

[Il Palazzo]

The mass does matter, it's what determines where the event horizon is. Everything has an Schwarzschild radius, just that for everything we have can interact with, the mass is mostly outside that radius.

We were talking about stripping an already collapsed singularity of the event horizon, right? Once it's collapsed, it doesn't matter if you'll stretch it, it already passed the point of no return.

So, wait, to make a black hole go faster, we throw stuff into it? Do you know what this means!?

Now we have an excuse to! What are we waiting for?

Faster? Not really. I don't think black holes can move. But black holes do grow if things are thrown into them, offsetting the Hawking radiation that slowly destroys them. You know, black holes act eerily like living beings under that context...

Spin faster, was what it was about.
And of course they can move. Same as e.g. a star, or an asteroid. On the large scale, it doesn't matter if the mass is located in a singularity, or not.
Any mass being attracted by a black hole, attracts it as well, so you could envision some crazy megaproject-y scheme of throwing stuff in from the direction you want it to go to.

[ECrownofFire]

Any mass being attracted by a black hole, attracts it as well, so you could envision some crazy megaproject-y scheme of throwing stuff in from the direction you want it to go to.

Of course, that would involve attracting a black hole towards yourself, which is generally a bad thing.

[MaximumZero]

Well, unless we gave it a trail of crumbs directed toward whatever we wanted eradicated, right? Best. Space Weapon. Ever.

[MetalSlimeHunt]

What we should do is create a socialist state, for people, like you and meeeeeeeee a trail of cryptic hints that will lead to a device that will create a nanobot swarm, programmed to eat their civilization and recreate humanity if somthing happens to us.

[Beeskee]

On the Kerr metric page I found this quote, hopefully this explains it better:

Overextreme Kerr solutions

The location of the event horizon is determined by the larger root of Δ = 0. When M < α(c2 / G), there are no (real valued) solutions to this equation (the Kerr metric), and there is no event horizon. With no event horizons to hide it from the rest of the universe, the black hole ceases to be a black hole and will instead be a naked singularity.[6]


Edit: Another quote on the same page:

Metrics

Disappearing event horizons exist in the Kerr metric, which is a spinning black hole in a vacuum. Specifically, if the angular momentum is high enough the event horizons will disappear.



Charged black holes have toroidal singularities (and so do charged, rotating black holes) but it's easier to spin up a black hole than it is to unbalance it's electrical charge.

[Il Palazzo]

Yes, yes. I'm not denying the existence of mathematical proofs of naked singularity emergence. I'm just saying that you don't seem to interpret these properly. I'm just as much of an armchair physicist as nearly everyone else here, but from what I gather, it's not that the spinning singularity stretches itself so much that it passes it's own Schwartzschild radius, and emerges from the event horizon, rather the spacetime gets so tangled up that it somehow allows energy to escape the "surface" of a singularity.
At least that's what I read in one of the articles that I linked to earlier.
God(and maybe Vector) knows if what Kerr metric actually means can be explained in layman's terms, I cannot comprehend the technicalities. If you feel like you grok the thing, go ahead and show us the light.

[Beeskee]

I don't know if I can explain it better, sorry.

[MaximumZero]

Well, time to get Vector on the horn.

[DJ]

How can an infinite density object exist in a finite density environment? Wouldn't it explode, since an infinite pressure is forcing it to do so? I can see how the problem is circumvented inside an event horizon, since the object can't expand faster than the speed of light, but I fail to see how it can exist outside an event horizon.

[andrea]

there are many infinites involved.
Gravity probably just increases faster than pressure, when radius shrink, which would mean that pressure will never be strong enough to oppose the increased gravitational pull. Unless there is some other force involved, like radiation pressure from the fusion reactions in the core of a star.
We don't see it normally because at low mass gravity isn't strong enough to start the shrinking process.

That is just what I suppose happens. I don't really know much about black holes. If somebody  here has more knowledge, I'd like to hear more about this topic.

[Vector]

I don't know much about physics, but with enough resources I should be able to math it out... I also happen to have a book about the physics of black holes that I've been ignoring for the past two years.  Can you tell me what, precisely, the questions you're trying to answer are?

[DJ]

Ah, but the gravity isn't infinite, since the object has a finite mass. Pressure is obviously always infinite, since you have infinite density object in a finite density environment.

Hm, how can a singularity form in the first place? As pressure approaches infinity, wouldn't it eventually match the gravity's pull and leave the matter hanging midway between black hole centre and event horizon?

[Il Palazzo]

Ah, but the gravity isn't infinite, since the object has a finite mass. Pressure is obviously always infinite, since you have infinite density object in a finite density environment.

Hm, how can a singularity form in the first place? As pressure approaches infinity, wouldn't it eventually match the gravity's pull and leave the matter hanging midway between black hole centre and event horizon?

But there is no pressure. The only characteristics the black hole retains of it's parent star, are mass, angular momentum, electric charge.(it's called the No Hair principle)
The collapsing star undergoes a number of steps - the gravity needs to be strong enough to overcome radiation pressure first, which happens when too much of heavy elements accumulated in the stellar core; then there's the electron degenerancy pressure, when atoms are squeezed so close together that the Pauli's exclusion principle(that no two identical fermions, e.g. electrons, protons, neutrons; but not e.g. photons; can occupy the same "spot") acting on free electrons becomes the main factor preventing matter from moving any closer. At this point, the classical gas pressure stops being accountable for.
With high enough mass, the electrons in the degenerate matter are so energetic, that they can combine with protons to create neutrons, and the result is a neutron star, where the pressure is provided by Pauli's exclusion principle acting on neutrons. The neutron star is much smaller, as there are no more energetic electrons filling the space between the nuclei and keeping them farther apart. The electron degenerancy pressure dissapears.
If the mass is high enough, the collapse isn't stopped by neutron degenerancy pressure, and the star collapses further, the surface gravity becoming high enough to prevent light from escaping, and we have a black hole.
The point is, once the consecutively appearing "pressures" are overcame, these stop acting any further. Once the last line of defence is broken, there is no more resistance preventing the collapse towards a singularity.
The density of a singularity is infinite, but there is no infinite, or any pressure at all.

I don't know much about physics, but with enough resources I should be able to math it out... I also happen to have a book about the physics of black holes that I've been ignoring for the past two years.  Can you tell me what, precisely, the questions you're trying to answer are?

I don't even know myself. It was about understanding how does a naked singularity appears.