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### How can non-infinitesimal Black holes form in finite time for a distant observer? [duplicate]

Say you are on earth observing a staring hypernova at safe distance from earth. Now as soon as the core collapses to its Schwarzschild radius the singularity would come into existence and so would ...
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### black hole potential well

Let d be the distance (in some coordinate system) from a particle to the event horizon of a black hole. For a particle starting at distance d>0 above the event horizon to rise away to a very large (...
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### Growing black holes and eternally falling objects

What happens to objects falling to a black hole (from outside observer's perspective)? There seem to be a consensus that because of time dilation, an object's fall towards event horizon will take a ...
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### How can a black hole grow, as seen by an outside observer? [duplicate]

How can a black hole grow in mass, if it takes an infinite time to cross the event horizon,  for matter approaching the black hole (as seen from an outside observer far from the black hole)? To make ...
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### How long does it take for the image of an object falling into a black hole to disappear?

From what I've read on other questions and answers, an outside observer cannot see an object fall into a black hole, but rather the image of the object will look like it is stuck on the surface of the ...
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### Can matter actually cross the event horizon effectively falling into a Black hole? [duplicate]

The answers I have seen do not take into effect the growth of the radius of the event horizon as significant amounts of matter get close to the existing event horizon. I would have expected that ...
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### Can matter actually go “inside” a black hole? [duplicate]

Pardon my question but I am no astro-physicist. If a black hole is a singularity, A.K.A. a single point in space-time which is infinitely small and which has an infinitely high density, can matter ...
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### Thoughts on Black Holes [duplicate]

Given that time slows to a stand-still at the event horizon of a Black Hole, how long would it take a black hole to form, from the perspective of an outside observer? It would seem, as a massive star ...
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### Can one observe a blackhole grow from outside its event horizon? [duplicate]

For an observer outside Black hole's event horizon nothing ever falls into the black hole . So if the observer waits for an eternity outside a super massive blackhole feeding on gas , will the ...
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### Does a black hole ever fully form to an outside observer? [duplicate]

According to general relativity, I had understood that time appears to slow down when looking into high gravitational fields from afar, so that as a black hole forms, the light from a collapsing star ...
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### How can matter reach the singularity of a black hole if time stops at the event horizon? [duplicate]

Black holes are said to be composed of two parts: A singularity at the center, where all the mass of the black hole is condensed in a point of zero volume. A black and empty ball delimited by the ...
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### Does black hole contain anything? [duplicate]

Suppose an object A is traveling towards black hole. For an observer outside it looks like A almost reached even horizon and is still trying to reach it. So from point of view of an observer all the ...
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### Infinity at event horizon boundary [duplicate]

It has been repeatedly explained to me that from the perspective of an outside observer a particle takes "infinite time" to cross the event horizon of a black hole. Also, according to these ...