Homogeneous Riemann surface
Template:Riemann surface property
Definition
A Riemann surface is termed homogeneous, transitive, conformally homogeneous, or conformally transitive if it satisfies the following equivalent conditions:
- The conformal automorphism group acts transitively on the points of the Riemann surface
- Given any two points of the Riemann surface, there is a bijective biholomorphic mapping from the surface to itself that sends the first point to the second.
Facts
- A compact Riemann surface is homogeneous if and only if it has genus zero or one. This follows from the fact that compact Riemann surfaces of higher genus have finite automorphism groups (alternatively, it follows from the fact that higher genus Riemann surfaces have certain special points called Weierstrass points).
- Further information: Compact and homogeneous iff genus zero or one
- Any simply connected Riemann surface is homogeneous. This follows from the classification of simply connected Riemann surfaces by the uniformization theorem: the only simply connected Riemann surfaces are the open unit disk, the Riemann sphere, and the complex plane.