Cosmology: Standard and Inflationary

In these lectures, I review the standard hot Big Bang cosmology, emphasizing its successes, its shortcomings, and its major challenges|developing a detailed understanding of the formation of structure in the universe and identifying the constituents of the ubiquitous dark matter. I then discuss the motivations for|and the fundamentals of|in ationary cosmology, particularly emphasizing the quantum origin of metric (density and gravity-wave) perturbations. In ation addresses the shortcomings of the standard cosmology, speci es the nature of the dark matter, and provides the \initial data" for structure formation. I conclude by addressing the implications of in ation for structure formation and discussing the different versions of cold dark matter. The ood of data|from the heavens and from earth|should in the next decade test in ation and discriminate between the di erent cold dark matter models. Supported in part by the DOE (at Chicago and Fermilab) and by NASA through grant NAG 5-2788