Timeline for Naked singularity
Current License: CC BY-SA 4.0
11 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 22, 2019 at 14:37 | comment | added | Zo the Relativist | @DvijMankad: because no non-causility can get outside of the horizon, and so our outside world is safe from being expmosed to them. If you believe in something like the holographic principle, then you can even think of the horizons as something like an inner boundary for the universe. | |
| Feb 22, 2019 at 14:07 | comment | added | user87745 | @JerrySchirmer This is probably a separate question that might have already been asked but why do CTCs hidden behind a horizon not scare us? They are as much a part of physics as they would be if not hidden behind a horizon, right? Thanks. | |
| Dec 16, 2018 at 5:13 | comment | added | Zo the Relativist | @ziususdra: the ctcs aren't related to the singularity. They don't intersect the singularity. They only don't affect the enveloping spacetime because they're hiddden behind the singularity. | |
| Dec 15, 2018 at 17:59 | comment | added | ziususdra | I fully agree but it is not the existence of a naked singularity which produces the problem but the presence of a singularity. We agree that a singularity is bad and generates problems and we hope that singularity will disappear in the quantum theory and therefore these problems too. My question is not about singularity but about naked singularity. If for a classical theory, I have a naked singularity why so much efforts to hide it behind a horizon if anyway a quantum theory will remove the singularity. | |
| Dec 15, 2018 at 15:19 | comment | added | Zo the Relativist | @ziususdra : of course it's not physical. It's a pathology in the spacetime which is evidence for the fact that you can't have naked singularities.Taking a pathology that is pointed out to you, and saying "but it's pathological, I don't expect that to be real!" is ridiculous. | |
| Dec 15, 2018 at 1:12 | comment | added | ziususdra | Yes but it is not physical, Kerr says it better than me (with my example of matter collapsing) youtube.com/watch?v=LeLkmS3PZ5g&t=26m | |
| Dec 14, 2018 at 22:07 | comment | added | Zo the Relativist | @ziususdra I googled for the first result. It is very well known that you get closed timelike curves by traversing through the ring singularity, and therefore, in a naked singularity solution, you expose them to the general spacetime. References are readily available to any level of rigor you want. | |
| Dec 14, 2018 at 21:08 | comment | added | ziususdra | It's written by unknown people with only 1 citation and their conclusion is trivial and not realistic. Trivial because they consider a motion in opposite direction to BH within the ergosphere, so of course this observer would need a velocity larger than the speed of light which permits CTC. But if we assume that no-one could go faster than speed of light, this observer doesn't exist. At the same time, in realistic solution, there is a fluid collapsing, which eliminates the multiple copies of spacetime in the maximal extension and therefore I'm not sure that it would really produce such effects | |
| Dec 14, 2018 at 20:22 | comment | added | Zo the Relativist | @ziususdra: Cosmic censorship doesn't fix the CTC problem in general (to my knowledge, there isn't a general proof that shows when CTC will show up), but it's somethign to consider in about some of these naked singularity solutions. The presence of CTC in the interior of Kerr solutions well known, but see: arxiv.org/pdf/0708.2324.pdf | |
| Dec 14, 2018 at 19:08 | comment | added | ziususdra | That's interesting. Do you have some reference linking naked singularity and closed timelike curves. Because at least we can give some counterexamples in both sides. A solution which has CTC's and which is not a naked singularity: the Godel universe. And a solution which is a naked singularity and doesn't have CTC like Schwarzschild with M<0. | |
| Dec 14, 2018 at 18:17 | history | answered | Zo the Relativist | CC BY-SA 4.0 |