Wikipedia:Articles for deletion/Dao's theorem on six circumcenters


 * The following discussion is an archived debate of the proposed deletion of the article below. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review).  No further edits should be made to this page.

The result was   delete. Article's subject is found to not be notable. &mdash; Coffee //  have a cup  //  beans  // 00:11, 13 March 2015 (UTC)

Dao's theorem on six circumcenters

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Yet another [self-]promotional article about a non-notable geometric theorem discovered by an unknown Vietnamese academic/hobbyist/whatever. Just like the previously deleted Dao's theorem, Dao's six point circle, Dao–Moses circle and Dao six-point circle. JohnBlackburne wordsdeeds 13:28, 5 March 2015 (UTC)
 * Speedy delete (WP:G4) if I am to believe the discussions from the AfD linked by nominator. Even if this is another, different theorem, I feel that G4 ought to apply. Tigraan (talk) 13:36, 5 March 2015 (UTC)
 * The removal of the CSD tag by an IP editor that is active at the same time as Hophap124 looks slightly suspicious, too. Oh well, WP:AGF and all that.Tigraan (talk) 14:29, 5 March 2015 (UTC)


 * Please see detail: Dao's theorem, Dao's six point circle, Dao–Moses circle and Dao six-point circle can not apply at here because them are differen with Dao's theorem on six circumcenters at here.

There are many subsection in Dao's theorem so them be deleted, and that time David Eppstein's commemt in Dao's theorem that:

There is a little bit of secondary sourcing (the Dergiades paper) but not enough to evaluate the impact of this result nor to pass the requirement of WP:GNG for multiple secondary sources...... —David Eppstein (talk) 19:00, 29 September 2014 (UTC)

So now if we apply David Eppstein's comment above we can keep this article. I would like comment again at here.--Hophap124 (talk) 07:42, 8 March 2015 (UTC)


 * Keep because some reason as follows:


 * First reason, the old article and this article are different: The old article write sum theorems of Dao Thanh Oai with common title is: Dao's theorem, The old article have some subsections: Dao's theorem on concurrent of three Euler lines, Dao six point circle, Dao six circumcenters theorem and Dao eight circles problem. So the old article and this article are different. And the old article Dao Thanh Oai is not enough english language to chat with You. He did not understand what you said that. And he didn't known wiki.


 * Second reason, enough reliable sources: The old article with subsections, but one subsection had only reliable source. But now this article has engough reliable sources: It has two papers in Forum Goemetricorum, one entry in Kimberling center, and two reviews in Zentralblatt MATH, one topic in Cut the Knot and some communiation of geometers in: Advanced Plane Geometry


 * Third reseon, not too soon: The theorem appear since 2013,


 * Fourth reseon, nice: The theorem nice as:


 * Seven circles theorem
 * Six circles theorem
 * Five circles theorem


 * Fiveth reseon, About Dao Thanh Oai is an amateur geometer, but I think he is not trivial why? He has many another results publish in journal in 2014. Publish in 2014 in somes Journal


 * His generalization of the Napoleon theorem: http://tube.geogebra.org/student/m660461


 * His generalization of the Gossard perspector theorem: http://tube.geogebra.org/student/m645553


 * His generalization of the Simson line theorem: http://tube.geogebra.org/student/m527653

--Hophap124 (talk) 14:24, 5 March 2015 (UTC)


 * We do not care about his many other results or the person, because notability is not inherited. Difference with the old articles are irrelevant for general deletion, it only saves from speedy deletion. Reliable sources do establish the existence of the theorem and its author, but not notability. Anything else? Tigraan (talk) 14:24, 5 March 2015 (UTC)


 * Yes Ok, dear, because JohnBlackburne comment that Dao Thanh Oai is an unknown Vietnamese academic/hobbyist/whatever !!!--Hophap124 (talk) 07:42, 8 March 2015 (UTC)


 * Two papers publish in MathScinet, Nikolaos Dergiades' paper MathScinet, Telv Cohld's paper ; one entry publish in Kimberling center, two reviews in Zentralblatt MATH. I think MathSciNet, Zentralblatt MATH, Encyclopedia of Triangle Centers are repliable sources.--Hophap124 (talk) 17:25, 5 March 2015 (UTC)


 * Note: This debate has been included in the list of Science-related deletion discussions. • Gene93k (talk) 16:03, 5 March 2015 (UTC)


 * * Let we see some remarks of expert geometers:


 * Remark 1: The editor-in-Chief of the journal wrote that: We reformulate and give an elegant proof of a wonderful theorem of Dao Thanh Oai concerning the centers of the circumcircles of the six triangles each bounded by the lines containing three consecutive sides of the hexagon.
 * No, the editor-in-Chief did not write that. That's the abstract of the (uncited) article by Dergiades. -- 120.17.74.76 (talk) 02:44, 6 March 2015 (UTC)
 * Thank to You dear but, the Editor in Chief of the journal, accepted with Dergiades' remark???--Hophap124 (talk) 04:56, 8 March 2015 (UTC)


 * Remark 2: The review in Zentralblatt MATH as follows: Let A1A2A3A4A5A6 be a hexagon, and let the subscripts in Ai be taken modulo 6. For 1 ≤ i ≤ 6, let Bi+3 be the point where Ai Ai+1 and Ai+2Ai+3 intersect, and let Gi+3 be the circumcenter of Ai Ai+1Bi+2. The author of the paper under review proves a theorem that he attributes to T. A. Dao and that states that if the hexagon is cyclic, then the lines G1G4, G2G5, and G3G6 are concurrent. Although the converse is possibly too good to be true, one may wonder about what exactly the hexagons that have this property are. One may also ask whether the point of concurrence has a different and simpler description that does not resort to the ear triangles or to their circumcenters. The proof demonstrates the power of the algebra of complex numbers in handling problems in plane geometry.


 * The afore-mentioned theorem of Dao seems to be new. At least it does not appear in the beautiful collection compiled by H. Walser [99 points of intersection. Examples – pictures – proofs. Washington, DC: The Mathematical Association of America (MAA) (2006; Zbl 1112.00006)], where it would fit nicely alongside other points of intersection pertaining to hexagons, such as points 16, 17, 24, 58, and 60.--Hophap124 (talk) 17:58, 5 March 2015 (UTC)


 * In short: WP:NOTFORUM (please stop discussing geometry here, we simply do not care) + WP:INDENT (indentation is used to follow who says what, and your layout of pages screws things up very badly) + WP:PRIMARY (papers published by the author do not directly count towards notability - only reviews and other secondary sources do). WP:BOOK can also help (just because something is published does not make it notable). Tigraan (talk) 21:22, 5 March 2015 (UTC)


 * I am sorry, I really don't understand what you say. I want to say that:


 * The primary sources, there is one sources: [Another Seven Circles Theorem http://www.cut-the-knot.org/m/Geometry/AnotherSevenCircles.shtml]


 * The secondary sources, there are two secondary sources: Nikolaos Dergiades, Dao’s Theorem on Six Circumcenters associated with a Cyclic Hexagon. Forum Geometricorum Volume 14 (2014) 243–246. MR 3260500 and Telv Cohl, A Purely Synthetic Proof of Dao’s Theorem on Six Circumcenters Associated with a Cyclic Hexagon. Forum Geometricorum Volume 14 (2014) 261–264 MR 3267837


 * The tertiary sources, there are three sources are: "Mowaffaq Hajja,Zbl 1301.51017, 2014 European Mathematical Society, FIZ Karlsruhe & Springer-Verlag". cornell.edu. "zbMATH - the first resource for mathematics". zbmath.org. and Kimberling.C X(3649) = KS(INTOUCH TRIANGLE)


 * or You mean: Forum Geometricorum is a normal forum??? see: http://www.worldcat.org/title/forum-geometricorum/oclc/487674101 --Hophap124 (talk) 01:12, 6 March 2015 (UTC)


 * If you do not understand what I say, you might wish to click on the links I left, which point to wikipedia policies that should be followed when editing here - they go in much greater detail that what I wrote. If you do not understand what they mean, I will kindly but firmly ask you to not edit anymore - competence is required. If you keep disrupting the encyclopedia, bad things could happen to you.
 * WP:NOTFORUM is not about the use of internet forums as sources; it is about the use of talk pages to go into detailed discussion of the topic at hand. We do not care about the topic itself; we care about writing about it. In a deletion discussion, the details of the mathematical proof of theorem XYZ are not interesting; what is interesting is whether those details or the theorem itself spurred great interest in the mathematical community, for instance. Discussing the content should only be done in relation to writing the article - for instance, "the article states that X, but actually that is incorrect use of a word that means specifically Y in this context".
 * Best regards, Tigraan (talk) 09:56, 6 March 2015 (UTC)


 * Dear I want said to you that Forum Geometricorum is not Forum normal. It is a journal, do you known that? If you don't known that, please see: http://forumgeom.fau.edu/statement.html ; http://forumgeom.fau.edu/index.html and http://forumgeom.fau.edu/index.html ; the Forum Geometricorum is a journal of Department mathematical sciences Florida Atlantic. --Hophap124 (talk) 10:09, 6 March 2015 (UTC)


 * Delete. Hasn't gotten any more notable since the prior AfDs. Comments in an amateur-oriented almost-uncited online journal are not independent coverage in reliable secondary sources. Opabinia regalis (talk) 02:09, 6 March 2015 (UTC)


 * Delete. I don't think that two uncited articles in an obscure online journal contribute to notability at all (we do have a Zentralblatt MATH review of the Dergiades article, but I don't think that counts for much). Also, the reasons in the past AfDs all still apply. And what on earth does "two triangles C_{12}C_{34}C_{56} and C_{45}C_{61}C_{23} are perpective" mean? -- 120.17.74.76 (talk) 02:38, 6 March 2015 (UTC)


 * Comment: "two triangles $$C_{12}C_{34}C_{56}$$ and $$C_{45}C_{61}C_{23}$$ are perpective" mean? It is mean: three lines $$C_{12}C_{45}, C_{34}C_{61}, C_{56}C_{23}$$ are concurrent, or three lines $$C_{12}C_{45}, C_{34}C_{61}, C_{56}C_{23}$$have a common point. see also Seven circles theorem.--Hophap124 (talk) 03:35, 6 March 2015 (UTC)


 * Delete. Non-notable marginalia.   Sławomir Biały  (talk) 03:39, 6 March 2015 (UTC)


 * File: Image showing Dao's theorem on six circumcenters generalizes Kosnita's theorem


 * Thank to Dear ,But I want let you known that the theorem is not Non-notable maginalia with some reseon as follows:


 * First reason: This theorem is a generalization of Kosnita theorem. When A2,A1 are the same point and A4,A3 are the same point, and A5,A6 are the same point. This theorem become Kosnita theorem. Could you see reason 1 at: Kosnita theorem and Dao's theorem on six circumcenters and Đào Thanh Oai-Francisco Javier Garcia Capitan, AdvancedPlaneGeometry, message 1717, message 1718


 * Second reason: If we write result only of the point of cuncurrence (given by the coordinates)> 24 pages to wrote result only


 * Third reason I think the theorem is nice as Seven circles theorem and difficulte to proof as Seven circles theorem


 * Delete and add something to mediawiki blacklist. WP:ORAntigng (talk) 14:13, 6 March 2015 (UTC)

Dear IP, the theorem is not original result. --Hophap124 (talk) 10:09, 6 March 2015 (UTC)

Dear Dr. ,

- Could you let me known that: Forum Geometricorum is a journal of Geometry or it is the forum? Some one said that the Forum Geometricorum is a normal forum online.

- Could you let me known that, this Dao theorem is a original research or not is original research, and some notes are reliable sources or are not?

Best regards --Hophap124 (talk) 12:56, 6 March 2015 (UTC)
 * "Some one said that the Forum Geometricorum is a normal forum online." I never said that, and you would know it if you had read my links. WP:NOTFORUM is about not turning a talk page into a discussion of the subject. You know that blue words are actually links you can click on, right? Tigraan (talk) 13:29, 6 March 2015 (UTC)


 * Who name for the theorem?? I didn't name for the theorem is Dao's theorem on six circumcenrs, the theorem name by Nikolaos Dergiades and Telv Cohl, and Paul Yiu(the Editor in Chief of the Journal). The first time, Dao Thanh Oai found and he named the theorem is Another Seven Circle theorem at here Another Seven Circles Theorem. But Nikolaos Dergiades, and Telv Cohl give the proof and publish, they call theorem is Dao six circumcenter theorem. Why I call theorem is Another seven circle theorem? Because it is like as: Seven circles theorem.--Hophap124 (talk) 01:00, 7 March 2015 (UTC)

- Could You give your ideas DanGong AlleinStein Cheers! Earthandmoon Legacypac Eightcirclestheorem ?--Hophap124 (talk) 07:10, 12 March 2015 (UTC)


 * note has now been blocked as a sockpuppet of .-- JohnBlackburne wordsdeeds 13:01, 12 March 2015 (UTC)
 * The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.