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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeMar 8th 2010
   • PermaLink
   Author: Urs
   Format: Markdowncreated [[rational homotopy equivalence]]

   created rational homotopy equivalence

2. • CommentRowNumber2.
   • CommentAuthorzskoda
   • CommentTimeMar 8th 2010
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   Author: zskoda
   Format: MarkdownIsn't for general spaces in addition to the rational equivalence of homotopy groups there a requirement to satisfy some condition on the Postnikov invariants as well ? I have not looked into the subject for a while but this is what my old memory says.

   Isn't for general spaces in addition to the rational equivalence of homotopy groups there a requirement to satisfy some condition on the Postnikov invariants as well ? I have not looked into the subject for a while but this is what my old memory says.

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeMar 8th 2010
   • PermaLink
   Author: Urs
   Format: Markdown> Isn't for general spaces in addition to the rational equivalence of homotopy groups there a requirement to satisfy some condition on the Postnikov invariants as well ? Ah, that could be. What I wrote applies to simply connected spaces (and I forgot to qualify this at the entry, but have now done so). By the way, at [[simply connected space]] it used to say that a simply connected space has to be connected, too. I removed that clause, as I don't think it matches common usage of the term "simply connected".

   Isn't for general spaces in addition to the rational equivalence of homotopy groups there a requirement to satisfy some condition on the Postnikov invariants as well ?

   Ah, that could be. What I wrote applies to simply connected spaces (and I forgot to qualify this at the entry, but have now done so).

   By the way, at simply connected space it used to say that a simply connected space has to be connected, too. I removed that clause, as I don't think it matches common usage of the term "simply connected".