Talk:Jordan curve theorem

message: I have just clarified the formal proof priority, sorry for doing it anonymously - have not noted I was logged out. JosefUrban (talk) 15:41, 4 January 2009 (UTC)
thread_title:  Formal proof 

message: An illustration could really improve the article and give credence to the claim that the concept is intuitive.--Cronholm144 10:14, 25 May 2007 (UTC)
replies: text: This has been done.98.67.108.12 (talk) 16:23, 25 August 2012 (UTC)
thread_title: Illustration

message: Hi guys.... I think this article needs to be expanded to encompass one of its most useful applications: 2D collision detection.
These sites give a good explanation of what the Jordan Curve Theorem means in a practical sense, and would help explain the concept to the less math-inclined.
The strategy:
http://tog.acm.org/editors/erich/ptinpoly/
Example implementation:
http://www.ecse.rpi.edu/Homepages/wrf/Research/Short_Notes/pnpoly.html  —Preceding unsigned comment added by Oticon6 (talk • contribs) 14:14, 1 April 2009 (UTC)
thread_title:  Applications in collision detection 

message: This paper seems like a nice reference. It has nice pictures in it. I hope one of you experts will include it somehow :)
https://facultystaff.richmond.edu/~wross/PDF/Jordan-revised.pdf  — Preceding unsigned comment added by 98.249.0.238 (talk) 00:37, 31 March 2012 (UTC)
replies: text: OK, I did. :-) Boris Tsirelson (talk) 17:44, 31 March 2012 (UTC)
thread_title:  suggested addition 

message: Now, he or she was "M. Reeken", and I added the "M", which is given in the references. So, "Who Reeken"? Please give the whole name.
Just calling someone "Reeken" or "Jordan" or "Jones" or "Schwartz" on first appearace is actually quite rude. If this is a person who wants to be referred to as "M. Reeken", then please give her or him that much. As for the present, we do not know if this was "Marion Reeken", "Michael Reeken", "Michelle Reeken", or "Madison Reeken".98.67.108.12 (talk) 16:29, 25 August 2012 (UTC)
replies: text: Michael, per the reference. Not that I know anything about him.—Emil J. 12:48, 27 August 2012 (UTC)
thread_title:  So, what about "M. Reeken"? 

message: An anon "IP 67.226.22.24" just added two phrases:
* The difficult part of the proof of the Jordan Curve theorem lies in the fact that the two disjoint components of the plane cut by the given curve are open and the curve itself is closed.
* The Jordan Polygonal theorem was presented at ICM 1998 by A. S. Zoch and soon afterwards a simple proof of the Jordan Curve theorem was presented to AMS by the same author using linear lemmas.
About the latter phrase.
As far as I know, this work by Zoch was presented on several conferences (including ICM 1998 and ICM 2002) in the form of short communication or contributed paper, but was never published in mathematical literature. Was it refereed? Is it notable?
About the former phrase.
Does it make sense?
Boris Tsirelson (talk) 20:06, 28 February 2013 (UTC)
replies: text: I’d say the answers are no and no.—Emil J. 13:07, 1 March 2013 (UTC)
thread_title:  Contribution of A.S. Zoch - is it notable? 

message: Does the cited 4-page proof of Filippov have an English translation anywhere??  (If not, could someone make students translate that proof on their math gradschool language exam and post the results online??)  It is a horrible tease to be directed to an "elementary" proof, only to find that it is in Russian.  — Preceding unsigned comment added by 173.66.241.122 (talk) 19:07, 8 May 2016 (UTC)
replies: text: The Russian text is available here. A similar proof by A.I. Vol'pert is here. Boris Tsirelson (talk) 17:58, 2 April 2019 (UTC)

text: A five-page proof, in English, given by Tvelberg in 1980, is available online for free. Why translate Filippov? Boris Tsirelson (talk) 19:52, 2 April 2019 (UTC)
thread_title:  Translation? 

message: Article says
:Furthermore, the complement of a Jordan arc in the plane is connected. 
How can that be right?  Should it say "not connected"? 67.164.113.165 (talk) 16:05, 2 April 2019 (UTC)
replies: text: I have removed the sentence, as, if "connected" is changed into "disconnected", one gets an assertion that is weaker than the theorem (exactly two connected components). Moreover, "furthermore" is not a synonymous of "in particular". D.Lazard (talk) 16:45, 2 April 2019 (UTC)
replies: text:  In the section you are discussing, a Jordan arc is defined there to be the image of an interval.  On the other hand, possibly this (true, not duplicative) comment does not belong in its present location; at least, not without a source that makes some connection with the statement of the theorem. --JBL (talk) 00:59, 3 April 2019 (UTC)
replies: text:  OK, my mistake. Thanks for reverting me. D.Lazard (talk) 07:31, 3 April 2019 (UTC)
thread_title:  complement of jordan arc 

message: Could someone please create Continuous curve and redirect it here?
:Or rather, redirect it to Curve#Topological curve? There we see
::"A simple closed curve is also called a Jordan curve. The Jordan curve theorem states that the set complement in a plane of a Jordan curve consists of two connected components (that is the curve divides the plane in two non-intersecting regions that are both connected)."
:Boris Tsirelson (talk) 06:39, 28 September 2019 (UTC)
replies: text: Works for me.  — Preceding unsigned comment added by 96.40.48.159 (talk) 06:55, 28 September 2019 (UTC)
replies: text: Well, I did. Boris Tsirelson (talk) 20:10, 28 September 2019 (UTC)
thread_title:  Continuous curve 

message: *   Hi. WP:BURDEN is mine, but I can't fulfill it while you're removing  what I'm working on. Please, refrain from removing content carelessly. In this particular case signified by WP:DIFFs above the deletion isn't justified (you have provided no provision of such). Refer to WP:PRESERVE. Except of WP:BLP/WP:CV NO known provision gives you a right to hastily remove anything. Use  (WP:TAGGING) to mark unsourced information before taking action. See also:
:* Wikipedia:Don't demolish the house while it's still being built.
:* WP:CANTFIX
Regards. --AXONOV (talk) ⚑ 08:25, 18 July 2021 (UTC)
replies: text: Your sandbox is here for preparing your work before adding it to an article. So the fact that your addition is still incomplete (fact that a reader is not supplosed to know of) is not a reason for not reverting it. You are invoking WP:CANTFIX. It applies here, as your edit is so vague that nobody (except you, maybe) can verify it. More, it seems unbelievable that Jordan curve theorem can be useful for computing with polygons, and even for studying them. So, WP:verifiability is fundamental here, simply for verifying that the assertion is correct. D.Lazard (talk) 09:08, 18 July 2021 (UTC)
replies: text:  Please see: Keep it, don't remove!. AXONOV (talk) ⚑ 11:28, 18 July 2021 (UTC)
thread_title:  Application 

message: I noticed someone changed the image to be the borders of a certain disputed parcel of land in the Middle East, and that made me realize the example image before that was the borders of Jordan, the country. I'm not an expert in math, so I would appreciate input from someone who actually understands the topic of the article, but I think those images only add confusion. I changed the image back to the original example image. Thesixthstaff (talk) 22:40, 22 January 2024 (UTC)
thread_title:  Illustration (again)