This volume deals with the fundamental concepts of space, time and matter. It presents a novel reformulation of both the special and general theory of relativity, in which time does not constitute the fourth dimesion in a conventional 4-dimensional space-time. Instead, the role of time is played by the flow of a vector field on a 3-dimesional space. The standard models of de Sitter, Schwarzschild and Kerr space-times are reformulated in a purely 3-dimensional manifold. The volume also presents a theory of Natter in which the fundamental particles, such as baryons and leptons, appear as a...