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arXiv · 1708.06854

Detecting exotic spheres in low dimensions using coker J

Mark Behrens·Michael Hill·Michael J. Hopkins·Mark Mahowald
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Abstract

Building off of the work of Kervaire and Milnor, and Hill, Hopkins, and Ravenel, Xu and Wang showed that the only odd dimensions n for which S^n has a unique differentiable structure are 1, 3, 5, and 61. We show that the only even dimensions below 140 for which S^n has a unique differentiable structure are 2, 6, 12, 56, and perhaps 4.

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Mark Behrens, Michael Hill, Michael J. Hopkins, Mark Mahowald. 2017-08-22. Detecting exotic spheres in low dimensions using coker J. https://doi.org/10.1112/jlms.12301

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