TASI Lectures: Cosmology for String Theorists

These notes provide a brief introduction to modern cosmology, focusing primarily on theoretical issues. Some attention is paid to aspects of potential interest to students of string theory, on both sides of the two-way street of cosmological constraints on string theory and stringy contributions to cosmology. Slightly updated version of lectures at the 1999 Theoretical Advanced Study Institute at the University of Colorado, Boulder. 1 Those who think of metaphysics as the most unconstrained or speculative of disciplines are misinformed; compared with cosmology, metaphysics is pedestrian and unimaginative. – Stephen Toulmin 1 [1] 1