= Rotational symmetry of a rational map
{title2=$R(gz)=hR(z)$}
Rotations of the domain and target <Riemann spheres> act as <Möbius transformations> represented by <SU(2) matrices>. A combined symmetry requires the equivariance identity $R(gz)=hR(z)$ for the corresponding transformations. Symmetry of the <Wronskian of a rational map> alone is insufficient: it tests the ramification directions, not the entire map. Target rotations preserve the <angular Jacobian of a rational map>, so an equivariant map has a domain-invariant angular density.
Back to article page
