In mathematics, specifically in differential topology, a Kervaire manifold K4n+2 is a piecewise-linear manifold of dimension 4n+2 constructed by Kervaire (1960) by plumbing together the tangent bundles of two 2n+1-spheres, and then gluing a ball to the result. In 10 dimensions this gives a piecewise-linear manifold with no smooth structure.
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Kervaire manifold Wikipedia(Text) CC BY-SA