This book is an introduction to special relativity for undergraduates in physics and mathematics. It is shaped by two convictions: (1) Relativity is not a "side issue" or "special topic". Rather, it is an essential unifying idea that illuminates every branch of physics. (2) The best way to teach relativity is to adopt a "spacetime" point of view from the start. A physical situation may appear different to different observers, but every observer must see the same four-dimensional spacetime.
Beginning with an introduction to spacetime ideas and basic relativistic effects, the book moves on to four-vectors, frames of reference, energy and momentum, and the spacetime description of waves. The second half of the book, written at a somewhat higher mathematical level, discusses relativistic forces, tensors, the physics of continuous systems such as fluids, and the electromagnetic field. Three appendices give a review of vector algebra and calculus, provide an historical account of the development of relativity, and describe the "kernel-index" notation used in advanced texts on special and general relativity.
The book should be accessible to students who have completed a calculus-based introductory physics course. It may be used as the main text for a semester-long course on special relativity, or as a supplemental text in courses on modern physics, mechanics, electromagnetism, or general relativity.