I read that singularity is point in space where is infinite gravitational force caused by collapsing something very big into something very small.

How can something with certain mass (star few thousand times bigger than Sun) create infinite gravitational force? It should be very strong, but finite gravitational force.

  • $\begingroup$ As you get closer and closer to the singularity, the gravitational force increases to infinity. This is true for any point particle. $\endgroup$ – probably_someone Apr 20 '18 at 6:32
  • $\begingroup$ That does not make sense. Singularity must be somewhere, so you eventually reach it. "Closer and closer" means you will never reach it. $\endgroup$ – Ondřej Apr 20 '18 at 7:43
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    $\begingroup$ You really need to read about black holes more. This is discussed a lot on the internet. But the big problem is that you expect it to make sense. Common (everyday) sense and singularities in general relativity will not mix. This is the biggest problem in learning relativity - you have to let go of some "common sense" ideas and replace them with other ideas. $\endgroup$ – StephenG Apr 20 '18 at 9:31
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    $\begingroup$ Rather than stating how to create something infinite from finite, I would actually tell you to think of singularities as places where the geometry is not defined. It's generally almost similar to the case of dividing by 0, where the division is not infinity, but undefined. $\endgroup$ – Yuzuriha Inori Apr 21 '18 at 4:53
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    $\begingroup$ The equation you wrote, is actually wrong. $X/0$ does not equal undefined, the whole operation is undefined. If you don't have something, you can't share it with anyone. The notion of sharing, or dividing, comes only when you have something. Else, the question is itself undefined. It's a fact of the maths involved, and anyone's non acceptance won't change it. $\endgroup$ – Yuzuriha Inori Apr 22 '18 at 12:27
  1. in our normal world, the earth's gravitational field is not strong enough on the micro level to be stronger then the other forces like strong force and EM force
  2. this is the reason that macro objects and atoms have stiffness and spatial volume, that the EM repulsion between nuclei and electrons are stronger then gravity on the micro level.

  3. now if you create too much mass in a too small spatial volume, the strong force and EM force is not stronger then gravity, and so gravity will crush everything, all the mass into a smaller and smaller spatial volume, until it has no volume

  4. now in math, gravity becomes infinite, but that means that is not defined in a 0 spatial volume


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