Extended relativity: Mass and the fifth dimension

A self-consistent relativistic formalism is presented which postulates that mass is the eigenvalue of a fifth momentum operator component. Lorentz covariance is generalized so that a systematic program for covariant wave equations can be formed. The fifth dimension is identified with cosmic time, resulting in a bias toward matter over antimatter for the universe. A distinction between μ ande also seems possible through the space-time extension.