Differences between the quantum mechanical and relativistic concepts of time are explained by using the equivalence principle. The resulting clock model calls for the microscopic equations of motion of atomic structure to be formulated in Minkowski space, and for photons to be described as four-dimensional localizations of energy. Because the properties of energy are universal the equations are able to be extended to include galaxies in spite of vast differences in lifetime. They show that symmetry exists between the electromagnetic fields of atoms and the gravitational fields of galaxies due to the presence in both of radial and transverse fields. Our description is fundamentally different from others because it is based on the conjugate variables energy and time rather than position and momentum.