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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeNov 6th 2012

    added a bit to framed manifold

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeNov 6th 2013
    • (edited Nov 6th 2013)

    fixed a silliness at framed manifold, due to me, which somebody kindly pointed out by email (the alleged proof that every orientable 3-manifold admits a framing had really been the trivial argument that every spin 3-manifold admits a framing, instead of the non-tautological argument that w 2w_2 also vanishes) fixed now.

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeNov 11th 2013

    after the example of the parallelizable sphereas I added the remark on division algebras and pointers to Adam’s original proof.

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeSep 3rd 2014

    added brief remark (here) on relation to intersection pairing and Kervaire invariant.

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeSep 11th 2014

    did a bunch of little edits today on the nnLab while the nnFormum was out of business. Now I don’t have the energy to announce them all. There were a few related to framings.

    • CommentRowNumber6.
    • CommentAuthorDavidRoberts
    • CommentTimeJul 17th 2017

    I added to framed manifold some results about which left invariant framings on compact simple simply-connected Lie groups give nontrivial elements in stable homotopy groups of spheres.

    There is a conjecture that for semisimple compact connected Lie groups with rank bigger than some fixed constant, all of the associated stable homotopy elements are zero. The guess for the constant is at or below 10, and the known facts show that for simple such Lie groups, at rank 4 and above this is true.

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