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### Could the singularity of a black hole just be an iron / dark matter sphere? [duplicate]

A singularity would break physics wouldn't it? How does a massive star collapse and suddenly fall into a point in space with no dimensions what so ever when it had a core and perfect balance between ...
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### Do the stellar remnant in a black hole have spatial extent? [duplicate]

I am not talking about event horizons. I am talking about the actual remnant of stellar collapse. Is it just a point, hence the problem with the singularity? Or does it have a finite volume that we ...
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About the information paradox in the black holes, isn't it possible in principle, that the "singularity" itself doesn't really exists, and its just the horizon plane, where the particles that falls ...
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### Why is a black hole black?

In general relativity (ignoring Hawking radiation), why is a black hole black? Why nothing, not even light, can escape from inside a black hole? To make the question simpler, say, why is a ...
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### Why singularity in a black hole, and not just “very dense”?

Why does there have to be a singularity in a black hole, and not just a very dense lump of matter of finite size? If there's any such thing as granularity of space, couldn't the "singularity" be just ...
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### Are black holes really singularities?

A popular assumption about black holes is that their gravity grows beyond any limit so it beats all repulsive forces and the matter collapses into a singularity. Is there any evidence for this ...
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### Why must a singularity form inside a black hole? [duplicate]

What is the exact reason that normal matter can not exist within an event horizon? I can understand how a super-dense object like a neutron star could accrete mass until its physical radius is less ...
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### Why does a singularity need to exist at the center of a black hole?

Sorry if this is a very basic question, but I am not a physicist, but this is something that has always intrigued me. I have read that the properties of a black hole are its mass, spin and angular ...
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### Fighting a black hole: Could a strong spherical shell inside an event horizon resist falling in to the singularity?

As a thought experiment imagine an incredibly strong spherical shell with a diameter a bit smaller than the event horizon of a particular large black hole. The shell is split into two hemispheres, ...
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### When does a singularity start to exist during a black hole formation?

Excuse me if the question is naïve. I am not a physicist. Let's imagine formation of a black hole from a homogeneous collapsing star. At certain moment when enough of matter is inside of a small ...
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### Does the escape velocity of a black hole exceed $c$ *before* a singularity is created?

As an offshoot of the question Can we have a black hole without a singularity? I'm curious if the point of no return at which the massive object is condemned to become a singularity happens before its ...
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### Can a black hole event horizon form before the singularity for an outside observer?

This is not a duplicate, my question is not about whether BHs have or don't have a singularity, but my question is whether, because of time dilation, no matter has reached the center and formed a ...