sphere theorem

Theorem 1 (sphere theorem).

If M is a differentiableMathworldPlanetmathPlanetmath orientable 3-manifold such that π2(M) is not trivial, then there exists an embedding S2M such that its image homotopy class is not equal to zero.

This theorem was established and proved by C. Papakyriakopoulos in 1957.

Title sphere theorem
Canonical name SphereTheorem
Date of creation 2013-03-22 15:45:35
Last modified on 2013-03-22 15:45:35
Owner juanman (12619)
Last modified by juanman (12619)
Numerical id 11
Author juanman (12619)
Entry type Theorem
Classification msc 57M35
Related topic 3Manifolds