Talk:Alexander horned sphere
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[edit] Origin of the name
What is the origin of the name of Alexander horned sphere? Could it be that it comes from Russian mathematician Pavel Sergeevich Alexandrov? --Romanm 11:09, 21 Jun 2004 (UTC)
No, [1] says that it's James Waddell Alexander. --Romanm 11:11, 21 Jun 2004 (UTC)
[edit] Double
In what sense is 'double' being used in the last paragraph? --Hvc 07:45, Jan 12, 2005 (UTC)
- The double of a manifold with boundary is obtained by taking the disjoint union of two copies of the manifold and using the "identity map" from the boundary of one copy to the other to get a quotient space. In other words, you glue two copies of a manifold along their boundaries making sure the map is not complicated. There needs to be a page on that concept. I'll do it sometime. The symbol often used for the double of M is 2M. --Chan-Ho 10:14, Jan 12, 2005 (UTC)
[edit] Too specialised
The phrase "the need for distinction between the TOP, DIFF, and PL categories" is totally meaningless and much of the rest of the article need more explanation to a lay reader. --Henrygb 11:14, 5 Mar 2005 (UTC)
- Perhaps it is totally meaningless to the lay reader, but certainly not for many mathematicians. Your point that this page is too specialized has some merit and more explanation would be better. Unfortunately, while the picture may be intuitively appealing, many interesting aspects of this object (some of which are explained in the article) are really only interesting to mathematicians and the layperson would have trouble indeed understanding. --Chan-Ho July 5, 2005 20:04 (UTC)
[edit] Image
Due to copyvio problems, the image previously in the article has been deleted. Since it's basically impossible to describe the Alexander horned sphere without an image, let's work on getting an image. Preferably one that can also be easily explained in the article to give a more precise description, e.g. not a picture that is too stylistic and obscures the mathematics. One possibility is to use images from Alexander's P.N.A.S. article; I think there is no copyvio problem there (check this!) but I think we can do better than that anyway. --Chan-Ho (Talk) 05:06, 17 December 2005 (UTC)
- Any feedback on the image I added? I think it is a bit on the stylish side, hopefully not too much. --Bernard 12:04, 22 October 2006 (UTC)
