Hopf invariant one, part I
Sanath Devalapurkar
Computing for is easy. By definition, , and by cellular approximation, we note that every map can be homotoped to a cellular map. It is obvious that all such cellular maps are trivial, so that if . The homotopy groups are more interesting, and can be computed via the Hurewicz theorem: Theorem (Hurewicz): There is […]