Light after Dark I is a collection of well-established, but up-to-date, science, both from theory and observation, including material from Charles Francis' published papers. Francis considers arguments, both for and against, two of the most controversial ideas in modern cosmology. Based on established physics, he suggests that unobserved and exotic substances, cold dark matter and dark energy, can be replaced by an improved understanding of the creation of large scale structure following the Big Bang. The structures and the physics of the universe as we observe it are described and placed in the context of Big Bang cosmology. Further topics include large scale structure, entropy and the arrow of time, the creation of the elements, the structure and evolution of galaxies and stars, Newtonian gravity, the structure of the Milky Way and other spiral galaxies, galaxy rotation curves and Friedmann cosmology. This fascinating exploration of the universe as it is revealed by physical theory and the observations of astronomers will appeal to students of astronomy and astrophysicists, and anyone intrigued by the universe in which we live. Written without equations and with helpful explanations of physical concepts, it is accessible to both scientists and non-specialist readers alike.