Other Models of the Hyperbolic Plane

Abstract

Up to this point, we have focused our attention exclusively on the upper half-plane model ℍ of the hyperbolic plane, but there are many other useful models. We explore in this chapter a second particular model, the Poincaré disc model ≄, of the hyperbolic plane, which we construct starting from the upper half-plane model. We go on to show that the construction used for the Poincaré disc is but one instance of a general construction for producing planar models of the hyperbolic plane.