Talk:Congruence (general relativity)

message: When I have time, I still need to add material on null geodesics.  Eventually I plan to add links to examples in :Category:Exact solutions in general relativity, once that category is sufficiently populated.  Eventually, there should be sufficiently many examples and figures to make the often misunderstood concepts of expansion, shear, and vorticity understood.---CH  (talk) 10:18, 19 September 2005 (UTC)
thread_title: Still needed

message: You've mentioned above the need for discussion of null congruences. A suggestion: for better organisation, it may be an idea to have separate sections (or articles, if there's much to discuss) for timelike and null congruences, as the maths may get slightly heavy. ---Mpatel  (talk) 08:44, 17 October 2005 (UTC)
replies: text: I'm not very happy with the organization either, in fact that's part of the reason why I ground to a halt while I regroup (wait for fresh inspiration while trying to finish other tasks).  Oh well, I hope we'll sort it all out in the end.---CH  (talk) 07:30, 18 October 2005 (UTC)
thread_title:  New sections (articles ?) 

message: I think that timelike congruence should be merged into this article, unless we can actually create a worthwhile article on timelike congruence (I know I certainly can't). ---Mpatel  (talk) 12:49, 19 October 2005 (UTC)
replies: text: Hmmm... some things are easier to do for timelike congruences, e.g. matching across a hypersurface orthogonal to some irrotational congruence; maybe that's why I was apparently planning to discuss null and timelike congruences separately.  Anyway, OK by me to merge them.  ---CH 04:39, 25 January 2006 (UTC)

text: Oh, I see, in the current version of this article I never got around to discussing the kinematics of  null congruences.  I remember now that I became unhappy with writing myself into a corner in the organization as I was writing this article, precisely because my attempts to start in on null congruences all seemed awkward from the standpoint of style.---CH 04:44, 25 January 2006 (UTC)

text: Even better, except for the first few paragraphs the present version is about timelike congruences, and since I was consistently opening each article with a section called something "physical interpertation", I remember now why from this point of view might make sense to have three articles, a short one on congruences in general which discusses some common properties and points at two more detailed articles on timelike and null congruences.  The advantage is this maintains consistency with a general vision for organizing articles for our project.  The disadvantage is that it seems awkward in this case because the common features ought to be discussed after the interpretation, yet they must go in the article which points at the two specialized articles which discuss the interpretation.  Yercchch, that's awkward. ---CH 04:50, 25 January 2006 (UTC)
thread_title:  Merger proposal 

message: I've created the stub optical scalars. MP   (talk) 19:57, 21 May 2006 (UTC)
thread_title: Related article created

message: An anon using IP  corrected a typo in the equation for the quantity I called Jdot.  We need to watch out for highly malicious vandalism in which some anon changes a correct equation to an incorrect equation, but this edit seems legitimate.  Thanks to the anon, and please register to make it easier for us!  ---CH 19:23, 2 June 2006 (UTC)
thread_title: Edit by 219.77.131.175

message: I created the original version of this article, did a good deal of work on it, and had been monitoring it, but I am leaving the WP and am now abandoning this article to its fate.
Just wanted to provide notice that I am only responsible (in part) for the last version I edited; see User:Hillman/Archive.  I emphatically do not vouch for anything you might see in more recent versions.
Good luck in your seach for information, regardless!---CH 23:07, 30 June 2006 (UTC)
thread_title: Students beware