# Avoiding Singularities

*Most recent answer: 11/30/2011*

Q:

Singularity! It always goes like this..."nothing can stop the collapse...singularity." ANd then we follow up with "monstrosity, physics is wrecked" and so on.
My question: isn't this an argumentum ad ignorantium? We don't know of a degeneracy pressure at that level, but mightn't there be something not in our present ken?
I'm not convinced that Black hole singularities are unavoidable.
Grateful fo any remarks...
John D'Onofrio (Dr D to my students)

- Dr D (age 70)

Geneseo, NY

- Dr D (age 70)

Geneseo, NY

A:

Nice question.

If General Relativity were exactly true at all scales, then somebody falling in to a black hole would hit a singularity. However, your speculation that something changes on a small scale is very much the standard view now. The existence of any sort of classical field makes extreme logical difficulties for quantum mechanics. Therefore it's generally assumed that the full theory of gravity will be quantized, with GR emerging as the large-scale limit. On the scale of quantum gravity (the Planck scale, ~ 10

Mike W.

unchecked post, Lee's in Paris.

If General Relativity were exactly true at all scales, then somebody falling in to a black hole would hit a singularity. However, your speculation that something changes on a small scale is very much the standard view now. The existence of any sort of classical field makes extreme logical difficulties for quantum mechanics. Therefore it's generally assumed that the full theory of gravity will be quantized, with GR emerging as the large-scale limit. On the scale of quantum gravity (the Planck scale, ~ 10

^{-33}cm) something else takes over, replacing the approach to the singularity. String theory is the most popular current approach to that problem.Mike W.

unchecked post, Lee's in Paris.

*(published on 11/30/2011)*