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The first example probably was an attempt to show how all CW-complexes are built up, but the description was too vague so I replaced it with a specific example of a CW-complex which is easier to describe for now. -Gauge 05:42, 2 Jun 2005 (UTC)

At the risk of being fussy, I suggest that the symbol for disjoint union operation be changed to${\displaystyle \bigsqcup }$ or${\displaystyle ⨆}$ from the present${\displaystyle ⨿}$ to be consistent with the articleDisjoint union. -Subh83(talk |contribs)19:51, 26 April 2011 (UTC)[reply]

Never mind that. The present notation is the standard for topological spaces. -Subh83(talk |contribs)19:55, 26 April 2011 (UTC)[reply]

Well, I studied quite a bit of topology (years ago) and the symbol confused me - it looks like a damaged upper-case${\displaystyle \pi }$ with Roman lettering type serifs or${\displaystyle \prod }$. Perhaps we could link the symbol to the articleDisjoint union?yoyo (talk)08:34, 16 November 2015 (UTC)[reply]

We need more information in the article, for example:

• What's the history of the term "adjunction space"?
• Who first used it?
• Who first defined it?
• Why use "adjunction"?
• And does it relate to a natural notion of "adjunct" elements in the space?
• If so, how is the adjunct element defined?

yoyo (talk)10:14, 16 November 2015 (UTC)[reply]

• Start-Class mathematics articles
• Low-priority mathematics articles