Projective plane, extended complex plane (pdf)

Κάντε κλικ στην εικόνα.

Abstract

First, I will introduce the basic definitions of two concepts: projective plane and extended complex plane. Then, I prove that the concept of cross ratio in the extended complex plane is the extension of cross ratio in the projective plane. 

Finally, I discuss the meaning of two concepts: the projective plane, and the extended complex plane.