Exotic Spheres

Some articles on exotic spheres, sphere, spheres:

Generalized Poincaré Conjecture - Exotic Spheres
... of manifolds that are homeomorphic, but not diffeomorphic, to the standard sphere, the exotic spheres you can interpret these as non-standard smooth structures on the standard (topological) sphere ... Thus the homotopy spheres that Milnor produced are homeomorphic (Top-isomorphic, and indeed piecewise linear homeomorphic) to the standard sphere Sn, but are not diffeomorphic ... Michel Kervaire and John Milnor showed that the oriented 7-sphere has 28 different smooth structures (or 15 ignoring orientations), and in higher dimensions there are usually ...
Alexander's Trick - Radial Extension - Exotic Spheres
... The failure of smooth radial extension and the success of PL radial extension yield exotic spheres via twisted spheres ... ...

Famous quotes containing the words spheres and/or exotic:

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    Susan Sontag (b. 1933)