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1. • CommentRowNumber1.
   • CommentAuthorHarry Gindi
   • CommentTimeJun 11th 2010
   • PermaLink
   Author: Harry Gindi
   Format: MarkdownItexThe pages [[BG]] and [[EG]] should definitely have redirects to [[classifying space]] and [[universal principal G-bundle]] respectively. I had to "ask an expert" what exactly they meant before I could even search for them. I would add the redirect, but I don't know how.

   The pages BG and EG should definitely have redirects to classifying space and universal principal G-bundle respectively. I had to “ask an expert” what exactly they meant before I could even search for them. I would add the redirect, but I don’t know how.

2. • CommentRowNumber2.
   • CommentAuthorDavidRoberts
   • CommentTimeJun 11th 2010
   • (edited Jun 11th 2010)
   • PermaLink
   Author: DavidRoberts
   Format: MarkdownItexI would be inclined not to add links to symbols like BG and EG. Where do you draw the line at making symbols links to the pages that name them? In good exposition one would say '...the classifying space $BG$' or '...the universal bundle $EG \to BG$...' or '...the universal $G$-space $EG$...' (EG sometimes isn't a bundle, but merely a space!) giving the writer a chance to link to a nearby word. And BG (modulo typesetting) is getting to be an overloaded combination. It stands for both the classifying space of a topological group (of which there are several explicit models) and the delooping of a group object, and these are related in subtle ways that need to be kept at the back of your thoughts.

   I would be inclined not to add links to symbols like BG and EG. Where do you draw the line at making symbols links to the pages that name them? In good exposition one would say ’…the classifying space $BG$’ or ’…the universal bundle $EG \to BG$…’ or ’…the universal $G$-space $EG$…’ (EG sometimes isn’t a bundle, but merely a space!) giving the writer a chance to link to a nearby word. And BG (modulo typesetting) is getting to be an overloaded combination. It stands for both the classifying space of a topological group (of which there are several explicit models) and the delooping of a group object, and these are related in subtle ways that need to be kept at the back of your thoughts.

3. • CommentRowNumber3.
   • CommentAuthorTobyBartels
   • CommentTimeJun 11th 2010
   • PermaLink
   Author: TobyBartels
   Format: MarkdownItexMy opinions align with David's here. If you really want to do *something* with [[BG]], then you could list its meanings there. Or redirect it to [[Notation]] and list things there. But really, it is bad form to link to [[BG]] at all. As David said, 'the [[classifying space]] $\mathcal{B}G$' is the way to do it. Then there is no need to do anything with [[BG]]. Although listing its meanings at [[Notation]] might still be a good idea. (I know that Eric would approve!)

   My opinions align with David’s here.

   If you really want to do something with BG, then you could list its meanings there. Or redirect it to Notation and list things there.

   But really, it is bad form to link to BG at all. As David said, ’the classifying space $\mathcal{B}G$’ is the way to do it. Then there is no need to do anything with BG.

   Although listing its meanings at Notation might still be a good idea. (I know that Eric would approve!)