An Overview About Evolution of TGD

Abstract

This chapter provides a bird's eye view about evolution of TGD. The geometrization of fundamental interactions assuming that space-times
are representable as 4-surfaces of H=M^4xCP_2 is wherefrom everything began. The two manners to understand TGD is TGD as a Poincare
invariant theory of gravitation obtained by fusing special and general relativities, and TGD as a generalization of string model obtained my replacing 1-dimensional strings with 3-surfaces. The fusion of these approaches leads to the notion of many-sheeted space-time.