Stallings–Zeeman theorem

Stallings–Zeeman theorem In mathematics, the Stallings–Zeeman theorem is a result in algebraic topology, used in the proof of the Poincaré conjecture for dimension greater than or equal to five. It is named after the mathematicians John R. Stallings and Christopher Zeeman.

Statement of the theorem Let M be a finite simplicial complex of dimension dim(M) = m ≥ 5. Suppose that M has the homotopy type of the m-dimensional sphere Sm and that M is locally piecewise linearly homeomorphic to m-dimensional Euclidean space Rm. Then M is homeomorphic to Sm under a map that is piecewise linear except possibly at a single point x. That is, M  {x} is piecewise linearly homeomorphic to Rm.

References Stallings, John (1962). "The piecewise-linear structure of Euclidean space". Proc. Cambridge Philos. Soc. 58: 481–488. doi:10.1017/s0305004100036756. MR0149457 Zeeman, Christopher (1961). "The generalised Poincaré conjecture". Bull. Amer. Math. Soc. 67: 270. doi:10.1090/S0002-9904-1961-10578-8. MR0124906 Categories: Theorems in algebraic topology