Hopf Invariant One
- Cool fact: you can show the non-existence of Hopf invariant one elements in dimensions \(1,2,4,8\) using K-theory.
- The argument is pretty clean, and the paper is only 8 pages:
See Mosh-Tang for the original proof using cohomology operations : https://www.maths.ed.ac.uk/~v1ranick/papers/moshtang.pdf.
- This also apparently includes computations of cohomology of Eilenberg-MacLane spaces.