Concept
Gravitation is a widely adopted textbook on Albert Einstein's general theory of relativity, written by Charles W. Misner, Kip S. Thorne, and John Archibald Wheeler. It was originally published by W. H. Freeman and Company in 1973 and reprinted by Princeton University Press in 2017. It is frequently abbreviated MTW (for its authors' last names). The cover illustration, drawn by Kenneth Gwin, is a line drawing of an apple with cuts in the skin to show the geodesics on its surface. The book contains 10 parts and 44 chapters, each beginning with a quotation. The bibliography has a long list of original sources and other notable books in the field. While this may not be considered the best introductory text because its coverage may overwhelm a newcomer, and even though parts of it are now out of date, it remains a highly valued reference for advanced graduate students and researchers. After a brief review of special relativity and flat spacetime, physics in curved spacetime is introduced and many aspects of general relativity are covered; particularly about the Einstein field equations and their implications, experimental confirmations, and alternatives to general relativity. Segments of history are included to summarize the ideas leading up to Einstein's theory. The book concludes by questioning the nature of spacetime and suggesting possible frontiers of research. Although the exposition on linearized gravity is detailed, one topic which is not covered is gravitoelectromagnetism. Some quantum mechanics is mentioned, but quantum field theory in curved spacetime and quantum gravity are not included. The topics covered are broadly divided into two "tracks", the first contains the core topics while the second has more advanced content. The first track can be read independently of the second track. The main text is supplemented by boxes containing extra information, which can be omitted without loss of continuity. Margin notes are also inserted to annotate the main text.