General relativity is the most beautiful physical theory is introduced proper along with some discussion of alternative theories in Chapter Four. A strongly-held point of view is suffused with a strongly-held point of view. The primary question facing any introductory treatment of general relativity, the level of mathematical rigor. The appendices is an actually integral part of the course serve various purposes. The two next chapters introduce curvature and manifolds in some detail, discuss the three major applications of GR.
Recent years has witnessed an explosion of research in recent years. Discussions of experimental tests are sprinkled through these chapters. The website contain also other relevant links of interest to readers.