13. sphere topology🔗

Topology of the 2-sphere: Van Kampen, simple connectivity, and the backward headline direction (homeomorphic-to-sphere ⇒ genus 0).

5 modules, 888 lines, under Jacobians/SphereTopology/.

References: Forster §10.5.

1. 13.1. Keystones
2. 13.2. Builds on
3. 13.3. SphereTopology
4. 13.4. SphereTopology.GenusSphereBackward
5. 13.5. SphereTopology.GenusZeroOfSphere
6. 13.6. SphereTopology.SphereSimplyConnected
7. 13.7. SphereTopology.VanKampen