Ultraparallel Theorem

In hyperbolic geometry, the ultraparallel theorem states that every pair of ultraparallel lines in the hyperbolic plane has a unique common perpendicular hyperbolic line.

Read more about Ultraparallel Theorem:  Proof in The Poincaré Half-plane Model, Proof in The Klein Model

Famous quotes containing the word theorem:

    “To insure the adoration of a theorem for any length of time, faith is not enough, a police force is needed as well.”
    —Albert Camus (1913–1960)