Talk:Exotic R4

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[edit] Attribution

Simon Donaldson needs to be in the article; see this, for example. Orthografer 05:14, 8 September 2006 (UTC)

I did more investigation, and as far as I understand it, Andrew Casson first had the construction (the Casson handle, which when attached to a standard 0-handle was the first exotic R4), but didn't know whether it was homeomorphic to R4, or whether it was exotic. Then Freedman's and Donaldson's work answered both questions with a "yes." I'm not sure what Taubes had to do with this. Orthografer 19:19, 8 September 2006 (UTC)

[edit] Poincaré conjecture

Poincaré conjecture is proven, so someone should modify and explain an exotic 4-sphere cannot exist. —Preceding unsigned comment added by 147.122.3.48 (talk) 09:58, 11 February 2008 (UTC)

This is the smooth Poincaré conjecture, which I believe is still open. Algebraist 15:53, 21 May 2008 (UTC)