Talk:Dark star (Newtonian mechanics)

message: ::Talk:Dark-energy star#Dark star
:merge with dark-energy star''
Found this article today, and felt it is a better/shorter name for it; if they are indeed the same thing. - RoyBoy 800 01:10, 13 August 2005 (UTC)
replies: text: I'd like a second opinion before giving up on it; however I'd presume putting these linking articles in their respective see also's would be appropriate? Perhaps also with a linked sentence in the article body explaining the difference. - RoyBoy 800 04:49, 15 August 2005 (UTC)
thread_title: [[Dark-energy star]]

message: If QM-based ideas like gravastars and dark energy stars are now beginning to proliferate, perhaps it's time to start thinking about a reorganisation: perhaps three main crosslinked pages: (1) NM's "dark stars", (2) GR's "black holes" and (3) QM's modified "radiating black hole" predictions. Then perhaps it might be natural to crosslink "gravastar" and "dark-energy star" pages to that new "QM black hole" page. It's a shame that there doesn't yet seem to be an accepted generic name for a "QM-modified black hole". ErkDemon 02:24, 19 August 2005 (UTC)
thread_title: QM

message: : This article contains a lot of POV material that isn't really suitable Wikipedia content. Much of it could be termed "original research", and it seems to be promoting (in a thinly veiled way) the idea that the modern scientific idea of black holes is wrong and should be replaced by the idea of a dark star. Whether or not this is true is irrelevant. The point is that Wikipedia is not the place for such advocacy to be published first. Wikipedia articles are supposed to be verifiable from material already published in reputable sources... and this does NOT include the drawing of dubious inferences from such sources, nor does it include the critiquing of such sources. Dubiously inferring and critiquing fall under the category of "original research".  I think this article should either be merged as historical background into the article on black holes, or else it should be re-written in a more verifiable and less POV way. 63.24.48.221 21:36, 24 September 2005 (UTC)
replies: text: I edited this article awhile back, and left it in OK shape (needed a lot of further work, but still passable).  It shouldn't go into a comparison with modern science other than to say this is base on an understanding of theory which is not the common view.   If I have the time, I'll start working on this in a couple of weeks.  Anyone else is free to start now, of course. :)  --Fcsuper 04:15, 9 November 2007 (UTC)
thread_title: What's wrong with present article

message: Yep, iffy! A proper qualification (attempted below) would probably be too long-winded, so perhaps it's better just to snip it out. "Agreed" was too strong a word considering the vagueness of "about the same" (I was thinking about the membrane paradigm when I typed that, but that doesn’t quite justify the sentence). Very probably misleading. Consider it gone. Cheers. ErkDemon 05:37, 31 October 2005 (UTC)
thread_title: yep, "problematic" statement identified, thanks

message: if people removed the merge part, then why is it not removed from BOTH pages?
69.22.224.249 21:56, 21 December 2005 (UTC)
thread_title:  merge not removed?!! 

message: I've been asked by User:Ken Arromdee to take a look at the disputed parts of this article, but am having a great deal of trouble sifting out what exactly is being disputed in the lengthy debate above. If the two of you would be willing to put a point-form list of points of contention below this comment, that would help a lot. To be clear, I'm not trying to act as any kind of arbiter, but will simply (as asked) state my views on the points of contention, where I'm capable of doing so (I like to think that I'm aware of the limits of my areas of knowledge). If things look sufficiently muddy, I'll link the page from Wikipedia:Pages needing attention/Physics and Wikipedia talk:WikiProject Physics, but from what I can see of the discussion above, it appears to be mostly a conflict of editing styles as opposed to irreconcilable differences over content. User:ErkDemon, is it ok with you if I take a look at this, or would you prefer that it just be put on PNA/P and WPP? --Christopher Thomas 23:46, 8 January 2006 (UTC)
replies: text: Hi Christopher. Yeah, fine, edit, delete, redirect, whatever. Don't care. Help yourself. ErkDemon 00:40, 24 April 2006 (UTC)
replies: text: I'm confused by one of the opening statements: "A dark star is a theoretical object under Newtonian mechanics that, due to its large mass, has a surface escape velocity that equals or exceeds the speed of light. Any light emitted at the surface of a dark star would thus be trapped by the star’s gravity rendering it dark, hence the name. [emphasis mine]" Under Newtonian dynamics, photons have no mass, and thus, a massive body's escape velocity is of no consequence to such particles. I would assume this article is written from the more modern perspective of curved spacetime--in which case, I don't understand the "under Newtonian mechanics" statement. Comments? -69.47.186.226 04:47, 19 June 2007 (UTC)
replies: text: In Newtonian mechanics, the effect of gravity on an object's motion is unrelated to its mass (as we all know, light objects fall at the same speed as heavy ones).  We could extend this to zero mass objects in two ways: either by saying that since it's independent of mass, it'll still happen when the mass is zero, or else by saying that while it's independent of mass, there must still be some mass, so it has no effect. Ken Arromdee 16:08, 19 June 2007 (UTC)
replies: text:  Hello, 69.47.186.226! The default behaviour of light under Newton's scheme was to be attracted and deflected by gravity, and that's the foundation that Michell and laPlace built on. Newton screwed up some other stuff about light, and when educators decided to "blank out" the historical errors in Newton's system to protect his posthumous reputation, they also wiped some of the good stuff, and started teaching that N had never said any such things. The history of C17th/C18th Newtonian physics (that you were taught in the C20th) was partly rewritten back in the C19th (and changed) to remove aspects that seemed to conflict with then-fashionable aether theory, and now, in the C21st, the consequences of some of these old bad edits are still in the current textbooks. People remember the "facts" that they were taught as kids, and when they grow up and become teachers and write textbooks, they tend to perpetuate the same duff information. To break the cycle you have to go back and check the original books and source documents. Principia and Opticks are currently in print, in paperback. ErkDemon 16:00, 15 September 2007 (UTC)
thread_title: Please specify areas of contention to be looked at.

message: I really know nothing about this but a number of sites, such as Enchanted Learning use the term "dark star" for any star that has stopped or doesn't emit light, including black dwarfs and brown dwarfs. Could someone please offer some form of explanation? I plan on asking the school physics teacher, but disambiguation by an expert would be more reliable. I'll check with astronomy professors at the university if no one can offer a suitable explanation, but that might take a while. Thanks. DUCK 17:29, 21 February 2006 (UTC)
replies: text: It is possible the term is being recycled by experts in the field.  If so, a disambiguation page may become necessary and verifiable sources for this new usages come up. --Fcsuper (talk) 02:16, 22 July 2008 (UTC)
thread_title:  Other Definition?! 

message: "Since observations all confirm the relativistic version, a dark star could not exist."
Which observations exactly? With no direct reference, validity of that statement is just that bit vague...
: Yeah, since GR dark stars can't be directly "seen" from outside on principle, making "observations" that confirm their existence would be difficult. The horizon radius is the same for DS and BH, and when we take Einstein's "general" 1911 gravitational time dilation argument and apply it to NM, it boosts the NM light-bending predictions so that it's difficult to see how one would tell the the two apart. We do have an indirect-radiation effect in dark stars that's absent in GR black holes, but if DS's conform to general thermodyanmic laws, the temperature of a stellar-sized dark star ought to be less than the cosmological background, so how do you tell those apart? 
:And now QM seems to make predicitons that are at least reasonably close to the DS phenomenology, so its difficult to know exactly what the editor was referring to.  
: The offending paragraph goes on: 
:: " Light is bent differently by a dark star and a black hole. Because light is massless under Newtonian mechanics, it could be (and was) argued that Newtonian gravity does not bend light at all. "
: The problem with that paragraph is that Isaac Newton himself seems to have diagreed.Principia and Opticks explicitly compare the action of a gravitational field to that of a variable-density optical medium, and gravitational light-bending was a pretty fundamental part of that idea. I'm sure that it's possible to find textbooks and lecturers who say that Newton's scheme didn't predict light-bending, but I'm afraid that just shows that physics people are sometimes really crap at historical fact-checking. 
: PS: I'm not sure that it's a good idea to talk about "relativity" as if its a single monolithic theory in the context of dark stars ... remember that Newton's ballistic-emission theory was a relativistic theory, too, and that's predominantly what people used to generate dark star descriptions. BET was pretty crappy in some respects, but it did obey the principle of relativity, so "BH vs DS" isn't a simplistic argument about "relative vs absolute" physics, it's a bit more subtle than that. ErkDemon 22:38, 31 July 2007 (UTC)
thread_title: Evidence for relativity

message: I have mixed feelings about this article: I originated it, so I feel that I have some responsibility for it, but I'm trying not to edit "controversial" physics pages, because it's obviously felt by some here that I'm not the right person to be doing that ... the article seems to collect junk edits that need changing, but nobody else seems to be fixing them ... my positions on this topic seem to be minority views, but then again, I seem to be the only active participant here who's actually read the source material. 
I also notice that the people who watch and maintain the "black hole" page removed the link that points here, so the consensus there seems to be that this page isn't wanted. The talk page also seems to have generated far too many arguments. So I think that perhaps the correct thing to do is to turn this page into a redirect that points to black hole, and be done with it, and avoid all the bad feeling. ErkDemon 23:04, 31 July 2007 (UTC)
replies: text: There's value in this article.  The black hole article has had discussion about it being too long.  Burdening it with this historic info is a step backward for that article.  This one needs cleaning up though.  I won't have time anytime soon, but maybe I'll jump back here in a couple of months. Fcsuper 23:18, 3 August 2007 (UTC)
thread_title:  rdir 

message: I've replaced the light-bending paragraph, because it didn't seem to make much sense as it was, and nobody else had fixed it. I don't know where that strange-looking "r=4M" business came from. Oops, I forgot to sign in. Today's edit was me. ErkDemon 01:32, 7 August 2007 (UTC)
thread_title:  Light-bending 

message: I've seen the term "dark star" used to refer to Newtonian black holes. It's not in use today, but is important for historical reasons.
With regards to the articles, this type of situation happens all the time. The usual solution is to use a disambiguation page. Dark star gets moved to Dark star (Newtonian mechanics), Dark star (dark matter) stays where it is (Dark matter star redirects to it, at present), and Dark energy star stays where it is. A new article, Dark star (disambiguation) is created, pointing to all of these concepts in the usual manner. A new article, Dark star, is created, which redirects to the disambiguation page.
Does this solution seem reasonable to everyone? --Christopher Thomas (talk) 07:05, 23 March 2010 (UTC)
replies: text: Makes sense to me. Scog (talk) 18:21, 23 March 2010 (UTC)

text: We already have a dab page, Dark Star. 76.66.194.32 (talk) 11:55, 25 March 2010 (UTC)
replies: text: Great; no need to build a new one, then. Any objections to me moving this page to Dark star (Newtonian mechanics)? --Christopher Thomas (talk) 18:12, 25 March 2010 (UTC)
replies: text: Very good idea. Thanks ErkDemon (talk) 11:39, 1 February 2021 (UTC)
thread_title: Disambiguation page

message: As there's been no objection in the week or so since this first came up, and some lukewarm support, I've moved the page. I'm now in the process of tweaking the Dark Star disambiguation page, fixing links to dark star and talk:dark star, and so forth. If there are any problems remaining past the end of March, it means I missed something; feel free to either fix it or notify whoever's performing housekeeping for the relevant pages/templates/etc. --Christopher Thomas (talk) 05:45, 31 March 2010 (UTC)
thread_title: Move completed, cleanup in process.

message: In Newtonian universe things FTL is possible, so mass maybe able to escape so there is no event horizon and it may still be unstable measured in billions of years as it is losing mass. 
As there is no event horizon it would create a naked singularity.
Thoughts
BernardZ (talk) 14:55, 1 April 2014 (UTC)
thread_title: Collapse & event horizon

message: Newtonian physicists thought that the sun radiation was powered by a gravity collapse. Similarly, a Dark star would be emitting light/energy but this energy would be trapped inside. Energy does not produce gravity under Newtonian physicists, would the gravity strength would be reducing? If so the Dark star would grow in size, maybe become unstable as its gravity force turns to energy. 
BernardZ (talk)
: Actually, according to Michell's argument that light gains energy when it goes downhill and loses energy when it goes uphill, trapped energy would give objects additional weight (and therefore, prersumably, gravitational mass).
: Imagine that you put a perfect internally-mirrored box onto a set of scales, and inject a light-complex into it. Once the light has settled down, Michell's argument says that the light hitting the bottom of the container ought to have more energy than light hitting the top - the box therefore ought to show a greater reading on the scales because of the imbalance in internal radiation pressures, which should push the box harder against the scales than if it was empty. So yes, it could be argued that in the Newtonian system, energy imparts the equivalent of gravitational mass. Whether anyone actually made this argument at the time, I don't know. ErkDemon (talk) 12:17, 1 February 2021 (UTC)
thread_title: Energy & gravity

message: I was reading through the article and it seems that it’s only theorized and needs to be found. Is it even possible for it to exist? 174.247.241.135 (talk) 01:31, 20 February 2022 (UTC)
thread_title:  Is this proven to exist?