As far as I know, as an object gets closer to an event horizon, gravitation time dilation makes it move slower from an outside perspective, so that it looks like it take an infinite amount of time for the object to reach the event horizon. It seems like a similar process should slow the formation of the black hole itself: As the star collapses, its gravitational time dilation make itself collapse more slowly.
This makes me wonder: from a perspective of an outside observer, can a singularity ever form?
E.g. someone on earth observers a massive star collapse, forming a black hole. From his perspective, the mass gets closer and closer, but does it ever form a singularity before the black hole evaporates?
Furthermore, if from a perspective of a mass collapsing into a black hole it’s time slows down and an outside universe “speeds up”, could this mean that the black hole evaporates before me, the mass, can become singularity?
In: Physics
Singularities are mathematical objects, not physical. They are points where solutions are undefined.
When referring to the singularity at the center of a black hole, we are referring to a region where General Relativity doesn’t spit out finite solution.
What goes on at the center of a black hole is something we don’t really know. But it’s not some kind of a physical object we call a singularity. It’s simply a region of space for which we have no mathematical framework that will give you coherent solutions. We can use General Relativity to solve everything happening at speeds below the speed of light, but it becomes rather useless at C.
For example, you can’t use GM to solve equations from the perspective of a photon because it spits out an answer where the photon is literally everywhere in the universe at once.
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