R. P. Kerr
2023 · arXiv
There is no proof that black holes contain singularities when they are generated by real physical bodies. Roger Penrose claimed sixty years ago that trapped surfaces inevitably lead to light rays of finite affine length (FALL's). Penrose and Stephen Hawking then asserted that these must end in actual singularities. When they could not prove this they decreed it to be self evident. It is shown that there are counterexamples through every point in the Kerr metric. These are asymptotic to at least one event horizon and do not end in singularities.
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Kerr dropped a paper last winter that is interesting about the claims of Hawking etc.. https://arxiv.org/abs/2312.00841 > In conclusion, I have tried to show that whatever the Penrose and Hawking theorems prove has nothing to do with Physics breaking down and singularities appearing. Of course, it is impossible to prove that these cannot exist, but it is extremely unlikely and goes against known physics.
Plenty of physicists are still "resistant" to the idea of black holes having a real singularity. The recent Kerr paper [0] only adds fuel to this resistance with its hilarious statement "Faith, not science!" about singularity proponents. [0]: https://arxiv.org/abs/2312.00841
FWIW, it's not clear that SgA* is actually a canonical black hole (nor that even such a thing truly exists in nature.) The EHT image is taken as confirmation but the accuracy of that technique has been called into question: https://arxiv.org/abs/2205.04623 Edit: In response to the downvotes, here are 2 very good sources who at least argue against the existence of singularities and their event horizons. 1: https://arxiv.org/pdf/2312.00841 2: https://uncnewsarchive.unc.edu/2014/09/23/carolinas-laura-me... I don't know exactly when science discussion turned into rigid dogma enforcement but we are certainly in that era presently.
> Hear [me] out Ok. > a black hole, but we have time backwards compared to the usual way we think of black holes Observations of our universe are straightforwardly understood -- and predicted -- by laying matter fields on an expanding Robertson-Walker metric. The same observations are not at all easy to understand by laying matter fields on a time-reversed Oppenheimer-Snyder-like black hole metric. The first thing you run into is that at the largest scales (i.e., where the solid angles subtended by galaxy clusters are small for observers like us) visible matter is arranged roughly isotropically and roughly homogeneously: we detect typical spiral galaxies (and more…
importantly various atomic line transitions associated with them, like the <https://en.wikipedia.org/wiki/Lyman-alpha_forest>) at all sorts of redshifts. Your homework would be to generate lightlike geodesics that can reproduce these observations at any time in a black-hole-like metric. If you can do that at for a single spacelike slice of your black hole, you then would want to work on evolving that slice using e.g. the <https://en.wikipedia.org/wiki/Initial_value_formulation_(gen...>. Just scratching the surface of how you would go about doing that would be an interesting research project for a layperson. Among other things, you would end up learning a lot more about what's in your second paragraph, and likely develop an idea about how much work is involved in writing down even a simple "pet theory" of physical cosomology that accords with observational data. Or at least you'd have a better idea of what observational data there is that needs to be accounted for. You'd also confront all sorts of open questions about the interiors of black holes where there is significant matter; that would be timely given the recent preprint by Roy Kerr at <https://arxiv.org/abs/2312.00841>.
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