Talk:Gravitational collapse

message: The talk of black hole singularities states as if it is a fact, which is not the case.  Although the idea of black holes are main stream, it is far from agreed upon.  Another theory is what scientists call gravastars.  There were more then a few articles in NewScientist if someone wants to add it, I will look it up myself if no one wants to do it. --ShaunMacPherson 15:24, 27 Apr 2004 (UTC)
thread_title:  fact?

message: I came here looking for thermodynamic equilibrium of a gas cloud in zero gravity. This is talking about falling into a black hole. Stellar dynamics of core collapse might be relevant, but this is weird.
Yeah. Stellar evolution refers to gravitational collapse for clouds to hydrostatic equilibrium, and core collapse for dying stars. Potatoswatter 21:01, 15 February 2007 (UTC)
thread_title:  gas clouds? 

message: this is an implosion on a huge scale?  —Preceding unsigned comment added by 97.81.109.173 (talk) 01:56, 17 February 2008 (UTC)
replies: text: Any implosion due to gravity. Everything in astrophysics is on a huge scale :v) . This article is misleading though, making it sound like a catastrophic event when that's not necessarily the case. Potatoswatter (talk) 18:51, 18 February 2008 (UTC)
thread_title:  So basically, 

message: the line "An initial smooth distribution of matter will eventually collapse " is nonsense. How is it supposed to even move if the matter distribution is smooth? - User:Striver  —Preceding unsigned comment added by 85.225.210.254 (talk) 09:52, 1 July 2008 (UTC)
replies: text: Smooth except at the edges. Assume it's a cloud floating in space. Potatoswatter (talk) 16:40, 1 July 2008 (UTC)
thread_title: nonsense

message: I suggest to add external link:
* Simulation of gravitational collapse
Its wonderful to see the mathematical predictions of general relativity demonstrated in an animation, but does the final circle represent a singularity or finite size star?  108.30.181.243 (talk) 17:17, 2 June 2016 (UTC)
thread_title:  Gravitational collapse simulation 

message: Removed the "Misleading" bullet dated Oct 2009 from the "Multiple issues" banner.  It may well be that the article is misleading, but there are no inline templates indicating so nor any Talk page comment about it.  Simply declaring the whole article "misleading" over five years of edits seems unhelpful, and, uh, misleading.  I've removed it.
If someone more knowledgeable than I am about this topic can affirm that the article is in fact misleading, please restore the banner to the article, and add some in-line references (or comments here) about it.  Mathglot (talk) 07:05, 24 July 2014 (UTC)
thread_title:  Removed "Misleading" banner. 

message: I've tried to make the article more readable, but it's possible that I've over-simplified or introduced inaccuracy, so if you know the subject please check! Snori (talk) 23:16, 25 June 2015 (UTC)
thread_title: Tidy-up - please check for accuracy

message: The article presently states: According to Einstein's theory, above the TOV limit no known form of cold matter can provide the force needed to oppose gravity in a new dynamical equilibrium. Hence, the collapse continues with nothing to stop it.
For starters, a fundamental problem with this analysis is that "matter" just doesn’t collapse; proton collapse should occur before electron collapse, and this is not addressed. If proton disintegration occurs prior to electron collapse, the reaction should be: proton → positron + 938MeV. Allowing for some neutrino and gamma production, this should result in a 450MeV (initial temperature) electrically neutral positron-electron plasma. This plasma will heat everything around it or escape the star. A 450MeV (initial temperature) positron-electron plasma, caused by collapsing protons, explains neutron star mass being limited to about 2.0 SM, the massive positron-electron jets emanating from neutron stars and 'black holes', TeV cosmic rays, the Eddington limit sometimes being exceeded (a jet from within the star heats material outside the star), the main source of radio noise associated with jets, and why stars with jets like IGR J11014-6103  are radio quiet. A hot star greater than 1.1 Schwarzschild radius could eject positron-electron plasma and still appear black by the tests we use. These stars should have similar chemical constituency as conventional stars and neutron stars (just protons, neutrons, ions, and electrons), but with a tiny percentage of positron generation providing the heat and fireworks. (A high pressure star like a 5SM black hole might have no ions.)  I used to believe nucleus collapse in neutron stars or 'black holes' should lead to quark production but the positron-electron jets indicate a different story. Structurally these stars are much like conventional visible stars just much hotter and denser. Virial energy provides support and the TOV equation does not apply. This 'black hole' star does NOT contain all light, nor even positrons/electrons above a certain temperature, but has the quirk you probably normally don't see it because of red shift, like many one-sided astrophysical jets. But you do see the positron-electron jets and everything associated with them, including gamma. Consider a hot star of radius 1.1 - 1.5 SR:  Above a certain temperature positron-electron plasma would escape the star but protons and ions could not; the positron-electron energy ejection could regulate star radius. Interesting that if a star like this would become hotter as radius decreases, there would also be more red shift effect on escaping radiation. My guess is star radius would vary somewhat and be >1.2 SR. If there is no jet this star could still ooze positron-electron plasma. 
Logically when matter collapses there should be a hierarchy of collapse, probably due to smaller particles having higher energy density than larger particles. First protons (or antiprotons) collapse, then positrons and electrons collapse, then neutrinos collapse, and so on. 108.30.181.243 (talk) 17:33, 28 May 2016 (UTC)
replies: text: Please use the Talk page to discuss improvements to the article.  This is not the place to expound on your ideas about the fundamental problems with Einstein's theory, interesting though they may be.  Instead, try submitting it to a peer-reviewed journal such as Physical Review Letters or Classical and Quantum Gravity.   Perhaps they'll publish it or give you suggestions for improvement. Mathglot (talk) 19:51, 15 June 2016 (UTC)
thread_title: Fundamental problem with conventional analysis: Collapse should mean proton collapse.

message: Removed citation request and qualified the statement. The article sensibly says a star smaller than 1.0 Schwarzschild radius doesn’t make sense. Its accepted that 2.0 solar mass neutron stars are probably about 2.0 Schwarzschild radius. The article states when the TOV limit is exceeded no known form of COLD matter can provide the force needed to oppose gravity, and collapse must also happen for a radius smaller than 1.0 Schwarzschild radius, with the outcome in either case being a collapse to a singularity. At least that leaves a gap for a HOT star between 1.0 - 2.0 Schwarzschild radius. Theoretically a 1.1 – 1.5 Schwarzschild radius star supported by viral energy would capture light (if only by absorption) although high energy leptons and gamma would escape. As a  star gets smaller (say below 1.5 SR) containment becomes more effective, and depending on whats being measured, a star would appear to turn off, while containing virial energy better too. Its probably going to boil down to if relativistic jets originate external to a neutron star or from within a neutron star. See IGR J11014-6103 Jet in Astrophysical jet. I think a big problem with the conventional singularity model is not that collapse happens below 1.0 SR, but that a collapsing star never gets smaller than at least 1.1 SR. 108.30.181.243 14:16, 29 May 2016 (UTC)
thread_title:  Gap in the range of possible compact star radius 

message: — Assignment last updated by Lzepeda12 (talk) 21:07, 26 April 2023 (UTC)
thread_title: Wiki Education assignment: 4A Wikipedia assignment