Timeline for Does blackhole merging break their event horizon segregation?
Current License: CC BY-SA 4.0
19 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Sep 22, 2022 at 12:49 | answer | added | Paul | timeline score: 0 | |
| Aug 9, 2020 at 18:50 | answer | added | benrg | timeline score: 1 | |
| Sep 9, 2019 at 8:39 | comment | added | Xenos | @MichaelWalsby To tell the Truth, Alice and Bob are not actually people. It's a Beauty-full nickname I gave to two Charm-ing particles, to cheer them Up when they're feeling Down. You never name your favorite particles?! That's Strange... | |
| Sep 7, 2019 at 17:35 | comment | added | Michael Walsby | How would Alice and Bob reach a black hole? All those we know of are far out of range and always will be.Assuming they got round that little difficulty,why would they be mad enough to dive into it? Spacecraft crews are highly selected,and mentally deranged crew members would be weeded out at an early stage.Assuming Alice and Bob somehow manage to fool the selection board (highly unlikely) why would other crew members not restrain them? By putting an ordinary working jacket on back to front,the empty arms could be tied behind their backs,thus converting an ordinary jacket into a strait jacket | |
| Sep 6, 2019 at 7:51 | comment | added | PM 2Ring | I think that if Alice & Bob cross the EHs just before the EHs touch then Alice & Bob might be causally connected, but I don't know enough GR to do the necessary maths (or to write a numerical simulation to test it), which is why I didn't post an answer when you first posted this question. | |
| Sep 6, 2019 at 7:47 | comment | added | PM 2Ring | They won't have plenty of time, though. Once you cross the EH, all motion must take you towards the core, although it's possible to increase the time a little, as discussed here. OTOH, that question is only about Schwarzschild BHs. Real BHs have a lot of angular momentum: most SMBHs are spinning at a significant fraction of lightspeed, which makes things more complicated, and may permit longer trajectories. | |
| Sep 6, 2019 at 7:31 | comment | added | Xenos | @PM2Ring Right, but if I get the video below right, then once Alice crosses the EH of a blackhole, she can go at the speed of light (or so) right after having corssed it, and so, she will have "plenty" of time before reaching the singularity (she will reach it, but later [from her point of view] than if free falling)? Suppose Bob does the same after crossing his BH EH, and "then" the BH EH touches each other and start merging. Are now both Alice and Bob (or their "photons" since they are at almost the speed of light) "causaly" relatable? | |
| Sep 5, 2019 at 18:00 | comment | added | peterh | Afaik there is some theorem saying that the total surface of the event horizons never decrease in any black hole configurations. | |
| Sep 5, 2019 at 16:59 | comment | added | PM 2Ring | FWIW, you can get the proper time of a freefalling body to reach the centre of a black hole, plus other interesting info, from the Hawking radiation calculator. | |
| Sep 5, 2019 at 16:56 | comment | added | PM 2Ring | Bear in mind that Alice and Bob rapidly fall towards the centres of their black holes, as do any photons they happen to emit. So you need SMBHs if you want them to last for more than a few milliseconds. But I'm not totally clear on what happens to the photon paths once the merging starts. | |
| Sep 5, 2019 at 16:25 | history | edited | Xenos | CC BY-SA 4.0 |
Try using the knowledge from the linked video to clarify the question
|
| S Sep 5, 2019 at 8:55 | history | suggested | jwodder | CC BY-SA 4.0 |
Proofreading
|
| Sep 5, 2019 at 7:46 | comment | added | Florin Andrei | related: astronomy.stackexchange.com/questions/32410/… | |
| Sep 5, 2019 at 0:00 | history | tweeted | twitter.com/StackAstronomy/status/1169399897151479813 | ||
| Sep 4, 2019 at 23:21 | review | Suggested edits | |||
| S Sep 5, 2019 at 8:55 | |||||
| Sep 4, 2019 at 15:53 | history | became hot network question | |||
| Sep 4, 2019 at 11:59 | answer | added | AtmosphericPrisonEscape | timeline score: 14 | |
| Sep 4, 2019 at 7:50 | review | First posts | |||
| Sep 4, 2019 at 8:57 | |||||
| Sep 4, 2019 at 7:49 | history | asked | Xenos | CC BY-SA 4.0 |