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May 12, 2020 at 4:27 vote accept skd
May 12, 2020 at 4:27 history edited skd CC BY-SA 4.0
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May 12, 2020 at 4:26 answer added skd timeline score: 2
May 9, 2019 at 0:36 comment added user51223 @user43326 I didn’t understand the point? If the map is a map of loop spaces then you may get a map as desired by the question. But, you don’t have such a map to start with!?!
May 8, 2019 at 16:28 comment added user43326 What if you take the bar construction on the map $\Omega ^2S^5 \to S^3$?
May 6, 2019 at 17:47 comment added user51223 At the prime $p=2$ there is no map $\Omega^2\Sigma^2 S^3\to S^3$ which is nonzero in homology. The existence of such a map will furnish 3-sphere with a commutative multiplication (up to homotopy) and that is known not to be the case at the prime $p=2$. I think this shows at this prime an extension as inin question cannot exist at $p=2$. I don’t know about off primes!
May 6, 2019 at 14:06 comment added Gustavo Granja The inclusion of the bottom cell does not even extend to the 8-skeleton. The attaching map of the 8-cell in the James construction is the Whitehead product [i_4,i_4] which is twice the Hopf map plus the suspension of the Blakers-Massey element (the generator of \pi_6(S^3)). You would need the Whitehead product to be twice the Hopf map in order for the extension to the 8-skeleton to exist.
May 5, 2019 at 23:49 comment added Dylan Wilson Maybe you mean 1.8? That says H-spaces X are a retract of \Loops\Sigma X, but surely the splitting is not unique. You can use that to build a map like the one you mention though. Anyway- I’m happy to forget about it, just wanted to make sure there wasn’t some contradiction lurking in my brain.
May 5, 2019 at 23:43 comment added Dylan Wilson Theorem 1.11 in that paper says that the James construction is the free topological monoid with the basepoint of X acting as the identity, which is not the same... did you mean to cite a different theorem? I’m really having trouble believing the statement is true...
May 5, 2019 at 20:38 comment added skd @DylanWilson This is in fact true (at least if X is path-connected), and was the original statement proved by James (Theorem 1.11 in his "Reduced product spaces").
May 5, 2019 at 20:21 comment added Dylan Wilson This isn’t relevant to your question, but you seem to claim that \Omega\Sigma X is the “free homotopy associative H-space” on X, which certainly isn’t true, right? Am I misunderstanding something?
May 5, 2019 at 17:53 history edited skd CC BY-SA 4.0
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May 5, 2019 at 17:24 history asked skd CC BY-SA 4.0