Talk:5-manifolds: 1-connected
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Revision as of 13:36, 16 December 2010 by Diarmuid Crowley (Talk | contribs)
1 Conjecture about mapping class groups of 1-connected 5-manifolds
Let be a closed, smooth, 1-connected 5-manifold, Matthias Kreck and Diarmuid Crowley conjecture that there is an isomorphism of abelian groups
where is the normal -type of as defined in [Kreck1999]. For example, if is Spinable with then
At present we are checking the details of the proof of this conjecture using the methods of [Kreck1999].
Diarmuid Crowley 10:02, 29 September 2009 (UTC)
2 Earlier work of Fang
The group was computed in [Fang1993] provided that has no -torsion and no -torsion.
Up-date of conjecture: module structure
If the conjecture above holds, then from the short exact sequence
we obtain an action of on the abelian group . Diarmuid Crowley and Matthias Kreck also conjecture that the action of is via the induced action on .