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• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeMar 25th 2019

Page created, but author did not leave any comments.

• CommentRowNumber2.
• CommentAuthorUrs
• CommentTimeMar 25th 2019

started some minimum

• CommentRowNumber3.
• CommentAuthorDavid_Corfield
• CommentTimeApr 27th 2019

Added a couple of properties.

• CommentRowNumber4.
• CommentAuthorUrs
• CommentTimeApr 27th 2019

Where you have “generator of the group of homotopy spheres” maybe you mean “generator of the group of exotic 7-spheres”?

• CommentRowNumber5.
• CommentAuthorDavid_Corfield
• CommentTimeApr 27th 2019
• (edited Apr 27th 2019)

I used precisely the words of Exotic spheres and curvature, p. 601.

But then maybe that’s shorthand from the paragraph before, so we should have “the group of diffeomorphism classes of oriented homotopy spheres in dimension 7”.

• CommentRowNumber6.
• CommentAuthorDavid_Corfield
• CommentTimeApr 27th 2019

Made that change.

• CommentRowNumber7.
• CommentAuthorUrs
• CommentTimeApr 27th 2019

Oh, I see. All right, thanks.

• CommentRowNumber8.
• CommentAuthorDavid_Corfield
• CommentTimeApr 27th 2019

Altered the wording of the Idea, since it sounded like it was one case out of many such biquotients.

• CommentRowNumber9.
• CommentAuthorUrs
• CommentTimeApr 27th 2019
• (edited Apr 27th 2019)

added pointer to these slides:

• Llohann D. Sperança, Explicit Constructions over the Exotic 8-sphere (pdf )

pointed out by David C. here.

I tried to find the corresponding article. Maybe it’s this one, which I added:

• Llohann D. Sperança, Pulling back the Gromoll-Meyer construction and models of exotic spheres, Proceedings of the American Mathematical Society 144.7 (2016): 3181-3196 (arXiv:1010.6039)

But the slides speak of “joint work with C. Duran and A. Rigas” and if this goes with a joint publication, then I haven’t found it yet.

• CommentRowNumber10.
• CommentAuthorDavid_Corfield
• CommentTimeApr 27th 2019

There is one joint paper

• C. Duran, A. Rigas, and L. Sperança. Bootstrapping Ad-equivariant maps, diffeomorphisms and involutions. Matematica Contemporanea, 35:27–39, 2010. (pdf)
• CommentRowNumber11.
• CommentAuthorUrs
• CommentTimeApr 27th 2019

Thanks! That’s not the one corresponding to those slides, but it’s interesting. I have added the pointer here (though that list of references is too long and unstructured already)

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