Say I want to represent points of the complex plane in the sphere $\Bbb S^2$ using stereographic projection. That is, the Riemann sphere:
Specifically, it would be nice to be able to:
- Given the coordinates $(x,y)$ of a point of the plane, see the point and its spherical image, and optionally, the line through the north pole and $(x,y,0)$.
- Given a circle in the plane, (that is, its center $(x,y)$ and its radius $r\gt 0$), see the circle and its spherical image.
- Optionally: it would be nice as well but is not necessary, being able to project in the sphere other kinds of sets, say polygons, sets of points, maybe straight lines, etc.
How can we do this? Is this already possible in Mathematica, I mean as built in functions?