The author is a professor at the University of California, Berkeley, who teaches a popular class on the same subject for non-science majors. This book is a great read for anyone interested in exploring the scientific facts behind topics like nuclear energy, terrorism, space exploration, global warming, and alternative energy. It is not a fast read, but the topics are covered in a conversational style and designed to be of interest to the lay public -- with the hard-core math and other more technical information relegated to footnotes in the back of the book. As another reader says in a quote on the book jacket, this book could also be entitled "Physics for Useful Citizens." Well worth reading.