"A clever introduction to the often intimidating concepts of special and general relativity, couched as a series of conversations between the author and his dog, Emmy. It may sound like a strange setup, but the somewhat kooky concept works well for explaining a field of physics that can sound, well, kooky to the uninitiated.... While keeping the math to a minimum, Orzel provides a clear and thorough primer. It might take some practice to start equating subatomic particles to running bunnies, but the reader will find that puzzling through the details is worth the effort."-Science News