Talk:General relativity/Archive 8

message: The relativity of simultaneity article is in very bad need of attention.  It is currently poorly written, and the last half is an anti-Einstein diatribe which belongs in relativity priority disputes if it belongs anywhere in Wikipedia.  I made an attempt to reduce this article to a stub, but other editors objected and reverted it back.
This is an important sub-topic of relativity, and it is a disgrace to have this important article in the hideous shape that it is now in.  I am hoping that others can help me to correct it.  Otherwise, I will attempt to have it deleted.  --EMS | Talk 02:38, 8 September 2006 (UTC)
thread_title:  relativity of simultaneity 

message: I've just created this section to dump this link, which may or may not be useful in the article (it may be better somewhere else). I'm still trying to get a hold of the original paper(s) by Penzias and Wilson which describes their findings. MP   (talk) 19:21, 16 September 2006 (UTC)
replies: text: NASA ADS, Penzias and Wilson to get PDF, click the link for GIF, then "other document options" then "get PDF". –Joke 19:34, 16 September 2006 (UTC)
replies: text: I found it by a little googling, but thanks anyway for responding quickly. Now the reference (currently number 9 in the article) comes out strangely. MP   (talk) 20:06, 16 September 2006 (UTC)
replies: text: This problem has been bugging me for a while now - how come the Arno and Penzias ref. (currently ref. number 15 in the article) doesn't appear correctly in the references section - the link is fine, but the url is highlighted (and not the name of the paper) ? Also, both the url and paper name seem to be in a single set of square brackets - argh. Help ! MP   (talk) 14:44, 27 September 2006 (UTC)
thread_title:  Penzias and Wilson refs.  

message: Just ran across this article, and I must say I think it's a horrible article, pushing a minority and rather silly POV.  As others have commented on the talk page, hyperbolic motion is not any sort of "mystery" with "two different resolutions".
At the current time, I'm not sure what to do about it, though - in the meantime I stuck an NPOV tag on it, to at least warn readers to look at the talk page.  Pervect 20:24, 17 September 2006 (UTC)
replies: text: That page is in need of a thoughtful rewrite.  It needs more math (but of the algebra/into. calculus type) and a short but thoughtful explanation of why the counter-arguments are wrong.  You should look at the talk page archives (if you have not done so already), as you can gleam some sense of what we have been through with it from those pages.  Do be advised that as soon as you start any major modification that Rod Ball will come out of the woodwork to challenge you, but me feeling is that we can cross that bridge when we come to it. --EMS | Talk 02:14, 19 September 2006 (UTC)
thread_title:  [[Bell's spaceship paradox]] 

message: I've included some important references regarding experimental results and theoretical predictions. I also found this site which could be useful (for other articles too): http://www2.corepower.com:8080/~relfaq/experiments.html. MP   (talk) 20:21, 18 September 2006 (UTC)
thread_title:  Update on references  

message: ... is reported here - the Shapiro effect. MP   (talk) 16:35, 20 September 2006 (UTC)
thread_title:  Another test of GR.... 

message: Is it just me, or is the article missing something glaringly obvious, such as discussions of relativistic hydrodynamics and relativistic thermodynamics ? The latter isn't even restricted to the study of black holes. MP   (talk) 00:37, 7 October 2006 (UTC)
thread_title:  Relationship to other physical theories 

message: I've boldly scrapped the equations in the electromagnetism subsection. Reason: The 'Relationship to other physical theories' seems to be about comparing some of the GR equations with their flat and non-relativistic counterparts; the first subsection - on inertia - does a good enough job in this regard . The subsections on conservation of energy and momentum and electromagnetism therefore seem redundant in terms of discussing the equations (I suppose that means I better scrap the equations in the conservation of energy-momentum subsection), as there are articles that discuss these issues in more detail. Is there an article on conservation of energy and momentum in general relativity (or just relativity) ? 
In fact, now that I think about it, for the other subsections it's perhaps better to leave the GR version of the equations in and just state any comparisons. For the electromagnetism subsection, the first and third equations could be left (as the second one happens to be the same). MP   (talk) 10:44, 10 October 2006 (UTC)
replies: text: I'm sure that you are on the right track.  I plopped the initial bunch of math into this article as something of mind dump when I was rewriting it.  As time has passed, that math has more and more resolved itself into being the most dense and obtuse part of this article.  It is good to see that mess being cleaned up--EMS | Talk 16:25, 10 October 2006 (UTC)
thread_title:  Scrapping some maths in the article 

message: User:Carrionluggage edited the end of the black hole section to read:
:A black hole exists at the center of our milky-way galaxy. This is proven by the concentration of mass too dense to be modeled (e.g.) by a cluster of neutron stars or any other candidate source of gravity. The movie from the Max Plank Institute for Astrophysics found at  shows actual observations of stellar orbits around the black hole. The shapes and sizes of the orbits are consistent with a black hole at the galactic center Sag A* and not with any other explanation yet proffered.
This is statement is not NPOV, and the edit history justification for it (that noone doubts that this is a black hole any longer) simply is not true.  There is no doubt that a supermassive gravitationally collapsed object exists at the galactic center.  However, there are still people who doubt that this is black hole.  OTOH, I have retained the link to the site showing the orbits of stars around that object, as the central object certainly is a black hole if general relativity is 100% correct, and that site very much justifies the statement that a black hole is thought to be there.  (Note that a journal article or two should also be cited.) --EMS | Talk 15:44, 17 October 2006 (UTC)
replies: text: Well, I suppose a lot of people are NPOV on how many and what kind of dinosaurs were carried on Noah's Ark (I've seen that debate in Wikipedia), but the debate on what is at the center of Sag A* was closed by the paper: "Stellar Dynamics in the Central Arcsecond of Our Galaxy" by R. Schödel, T. Ott, R. Genzel, A. Ekhart, N. Mouawad, and T. Alexander, Astrophys. J. 596, 1015-1034 (2003) (3 yrs ago). To quote them, their observations "(leave) a central supermassive black hole as the only plausible explanation."  You want to argue - come up with a theory that fits 3 million solar masses in 1/2 parsec (see their section 5) and that mass is not a black hole.  So it is not an NPOV issue since Oct 20, 2003 unless somebody comes up with a refereed paper disputing the issue.  Carrionluggage 21:04, 17 October 2006 (UTC)
replies: text: Black holes have not been proven to exist and there is serious speculation among some scientists that they may not.  So, writing that "A black hole exists in the center of our galaxy" is incorrect.  That there is still speculation as to whether black holes exist or not is evident here . User:Alfred Centauri 21:50, 17 October 2006 (UTC)

text: You have referred to a non-refereed news release. Chapline, has, however, contributed in his day some respectable physics (I believe he worked on the hydrogen bomb project); he published on shock waves in 1973. Nevertheless his paper in "Texas Conference on Relativistic Astrophysics" is unrefereed.  I will try to see if there is a refereed version and citations to it. Anyway it seems to deal mainly with stellar mass "black holes" not supermassive ones. Carrionluggage 22:37, 17 October 2006 (UTC)

text: A search of the NASA ADS system for publications of G. Chapline did not yield any publications of the kind you implicitly refer to. This search engine finds not only publications but citations to them.  It is free and accessible at: . I assume that Dr. Chapline is being roundly ignored by all but the Livermore press office, but I sent them a query and will let you know if anything more emerges.
Here is what I got with my search:Query Results from the Astronomy Database
	Go to bottom of page
Selected and retrieved 15 abstracts.	
# 	Bibcode 	
	Score 	Date 	List of Links
	Authors 	
	Title 	
	Access Control Help
1	 2006AIPC..822..160C	
	0.769	04/2006	A                      X              T      R  C                      U      
	Chapline, George; Mazur, Pawel	
	Tommy Gold Revisited: Why Doesn't the Universe Rotate?
2	 1990fqm..meet...27C	
	0.769	08/1990	A                                                                          U      
	Chapline, G. F.	
	Information flow in quantum mechanics: The quantum Maxwell demon
3	 1989nesa.conf..561C	
	0.769	00/1989	
	Chapline, G.	
	Cold Confusion
4	 1982PhRvD..25..911C	
	0.769	02/1982	        E                                      R  C                          H  
	Chapline, George F.	
	Binding of fractional charges to nuclei
5	 1977PhRvD..16..450C	
	0.769	07/1977	        E                                      R  C                      U  H  
	Chapline, George; Nauenberg, Michael	
	Asymptotic freedom and the baryon-quark phase transition
6	 1977NYASA.302..191C	
	0.769	00/1977	                                        T          C                      U      
	Chapline, George; Nauenberg, Michael	
	On the Possible Existence of Quark Stars
7	 1976Natur.261..550C	
	0.769	06/1976	A                                                  C                      U  H  
	Chapline, G. F.	
	Quarks in the early Universe
8	 1975Natur.253..251C	
	0.769	01/1975	A                                                  C                              
	Chapline, G. F.	
	Cosmological effects of primordial black holes
9	 1974ApJ...192L..57W	
	0.769	09/1974	A          F  G                              R  C                              
	Weaver, T. A.; Chapline, G. F.	
	Dissipation in Supernova Shock Waves
10	 1974PhRvD..10.1064C	
	0.769	08/1974	A      E                                      R                          U  H  
	Chapline, G. F.; Nuckolls, J.; Wood, L. L.	
	Gravitational-radiation production using nuclear explosions
11	 1974BAAS....6Q.274W	
	0.769	03/1974	                                                    C                              
	Weaver, Thomas; Chapline, George; Wood, Lowell; Silk, Joseph	
	The Structure of Supernova Shocks
12	 1974BAAS....6..279D	
	0.769	03/1974	
	Dahlbacka, G. H.; Chapline, G. F.; Weaver, T. A.	
	Pion Gamma Ray Emission from Black Holes
13	 1974Natur.250...36D	
	0.769	00/1974	                                                    C                      U      
	Dahlbacka, G. H.; Chapline, G. F.; Weaver, T. A.	
	Gamma Rays from Black holes
14	 1973ApJ...184.1041C	
	0.769	09/1973	A          F  G                              R  C                      U      
	Chapline, George, Jr.; Stevens, John	
	Effect of Compton Scattering on X-Ray Spectra
15	 1973ApJ...179..277N	
	0.769	01/1973	A          F  G                              R  C                              
	Nauenberg, Michael; Chapline, George, Jr.	
	DETERMINAT10N of Properties of Cold Stars in General Relativity by a Variational Method . .
Carrionluggage 22:48, 17 October 2006 (UTC)
replies: text: A couple of refereed articles on black hole alternatives:  , .  Here  is a refereed article that argues that Sag A has an event horizon.  The fact that this argument is being made in an article published in 2006 would seem to argue against your assertion that Sag A has been known to be a black hole since 2003. Alfred Centauri 23:52, 17 October 2006 (UTC)

text: Hopefully this is settled.  My concern was the absolutism of the statement more than anything else.  If you look at my home page you will see that I do indeed have anti-black-hole views and an OR theory of my own.  Normally I would not touch the Black Holes section because of that, but your statement was so over-the-top that I felt that I was on safe ground in making my revisions.  (BTW - That section has always been somewhat tepid since I am the one who wrote it as part of the last major rewrite of this article.    So it is good to see it finally being developed into something more than the very cut-and-dried thing that I felt both safe and honest in writing.  I won't tolerate 100% certainly that black holes exist, but I assure you that I will be even quicker in reverting anything that says that black holes don't exist.) --EMS | Talk 03:02, 18 October 2006 (UTC)
thread_title:  Black holes and NPOV 

message: I am trying to have the article on Abhas Mitra removed.  Abhas Mitra is a contributor to the Magnetospheric eternally collapsing object or MECO theory, and apparently coined the term.  In a nutshell, the MECO theory claims that radiation pressures prevent the collapse of an object into a black hole, and the you instead get an "eternally collapsing object" or ECO.  If this ECO has a strong magntic field, that further prevents collapse, and makes the object a MECO.  As this is being thoerized in the context of GR, I see this a being a theory which claims that GR is not GR.  Several such theories are noted in the black hole article.    
I won't contest that the MECO is encyclopedic, but I do not see that the notability extents to Dr. Mitra.  Please see
Wikipedia:Articles for deletion/Abhas Mitra.  Thanks, EMS | Talk 03:37, 6 November 2006 (UTC)
thread_title:  Abhas Mitra article deletion 

message: Because of the current FA nomination, I have expanded the lead to this article to be more complete and comprehensive.  Others can help by adding in appropriate citations for what I have added, as I am a weak bibliographer.  IMO, this fills the biggest hole in the article if it is to obtain FA status.  Other possible issues are the size of the article and possibly the technical level of the section on comparisons with other theories.  However, the comprehensive nature of the total material covered is most likely one of the reasons for the Fa nomination in the first place.  In any case, let's see what others have to say about this article and adjust it as necessary. --EMS | Talk 21:50, 26 November 2006 (UTC)
thread_title:  FA nomination 

message: Could the term 'general theory of relativity' be used right at the very start of the article (as an additional definition) ? The term 'general relativity' is more commonly used nowadays, but perhaps the alternative could be included (Einstein used it, but it was some time ago). Any thoughts ? MP   (talk) 21:58, 30 January 2007 (UTC)
replies: text: Done.  I added two alternatives actually.  Take a look and tell me what you think. --EMS | Talk 22:09, 30 January 2007 (UTC)
replies: text: It looks good. I'm not sure about the square brackets though; maybe this is a grammatical convention that I'm not familiar with. Thanks for adding the two names though. MP   (talk) 16:07, 31 January 2007 (UTC)
thread_title:  Additional definition ? 

message: * Shouldn't be a section about criticism of Einstein's theories? I myself am not a physicist nor do I understand all of what's written in this page, but I know that there has been some criticism for the relativity theory, and I can't find it here, a section about that would be great. 84.36.26.66 20:43, 13 February 2007 (UTC)
replies: text: There is a section on alternative theories and an entire separate article on Alternatives to general relativity. What more do you want? I am not aware of any evidence against general relativity. And the only theoretical difficulty is what happens at the singularities (at the center of a black hole and at the beginning of the universe)? JRSpriggs 08:55, 14 February 2007 (UTC)
thread_title:  Criticism 

message: Regarding my recent addition of this template I note that in my opinion article has some unnecesary wordings in the introductory paragraphs. Like some of the "..The first success of general relativity was in explaining the anomalous perihelion precession of Mercury. Then in 1919, Sir Arthur Eddington announced that observations of stars near the eclipsed Sun confirmed general relativity's prediction that massive objects bend light. Since then, many other observations and experiments have confirmed many of the predictions of general relativity, including gravitational time dilation, the gravitational redshift of light, signal delay, and gravitational radiation. In addition, numerous observations are interpreted as confirming one of general relativity's most mysterious and exotic predictions, the existence of black holes..." in the second paragraph could be shortened or even totally moved elsewhere. It may help to shorten the 4th paragraph, too. My first reaction with tagging the article was based on the visual impression. Cheers. --Biblbroks's talk 00:45, 12 April 2007 (UTC)
replies: text: As already Max Born remarked the connections of GR with experience are slender. Therefore, it seems that some people believe it's necessary to mention all these slender proofs already in the introduction. Actually most effects are already predicted by SR and Sir Isaac Newton's law of universal gravitation just treating the relativistic mass as ordinary mass. The  gravitational time dilation, the gravitational redshift and are more or less the same effect and exactly of the same size as predicted by SR plus Newton and verified by experiments. The perihelion precession of Mercury and bending of light were predicted by Einstein in 1916 to be somewhat larger than expected by SR plus Newton. But, the experimental results are still somewhat ambiguous. 84.59.47.182 08:17, 12 April 2007 (UTC)
replies: text: Regrettably, the two theories you mentioned contradict each other. GTR is the result of resolving the contradictions. JRSpriggs 08:26, 12 April 2007 (UTC)
replies: text:  As I understand, you think that special relativity and Isaac Newton's law of universal gravitation contradict each other. Sorry, but I can't follow you. Can you please explain that in more detail ? 84.59.47.182 09:41, 12 April 2007 (UTC)
replies: text:  Kindly explain how this relates to editing this article.  Please see the notice at the top of this talk page.  There are other venues to which you can take this question. --EMS | Talk 19:54, 12 April 2007 (UTC)
replies: text: See chapter 7, "Incompatibility of Gravity and Special Relativity", in Gravitation (book). JRSpriggs 04:51, 13 April 2007 (UTC)
replies: text:  There is definitely no resonable doubt about special relativity (E = mc2). Therefore, special relativity can't be incompatible with gravity, that's ridiculous. 84.59.32.187 20:13, 13 April 2007 (UTC)
thread_title:  Too lengthy introduction 

message: , good thing to mention in the article. —The preceding unsigned comment was added by 74.113.107.4 (talk) 14:47, 15 April 2007 (UTC)
thread_title:  [[Gravity Probe B]] backs general relativy 

message: Moved the following non-NPOV edit by  out of main article Silly rabbit 22:08, 20 April 2007 (UTC)
thread_title:  Status