Elliptic geometry

Elliptic geometry is a non-Euclidean geometry developed by German geometer Bernhard Riemann. It is based on a change in Euclid's fifth postulate, that through a point outside a line, there is one line parallel to the other line. In elliptic geometry, there are no parallel lines at all. It is very much like spherical geometry. Elliptic geometry has the property that a triangle will have more than 180 degrees. This is best understood on a globe. Two right angles on the equator, a quarter of the circumference away from each other, make the base, and the angle on the pole is also 90 degrees. This creates a 270 degree triangle, impossible in Euclidean geometry.