Several years ago when "A Brief History of Time" became a scientific best-seller I had a copy and was tearing through it before the ink had dried. Soon after that I was floundering around in Stephen Hawking’s ideas like a drunk in a blackened room. I banished that book, until the guide to it came out. That one lost me too.
I was gladdened by the fact that this was a slim volume and that Mr. Bennet was going to be tackling Einstein's theory of relativity, and not the whole tangled thicket of physics, with Bosun-Higgs, quarks and multiple dimensions.
In fact Mr. Bennet does an admirable job in slowly and skillfully unwinding the mysteries of relativity and making some of the wonkier aspects easily understandable to the layman. He breaks down the basic concepts of relativity, and while doing so makes a convincing case for its importance in science, philosophy and everyday thought. He also wends his way through both the general and special theories, and points out the similarities and the differences. Some of the strongest parts of the book are when Mr. Bennet breaks down and illustrates relativity in detail using what he calls "thought experiments." These clever yet simple sections take the most complicated concepts and spells them out in detail in small, understandable sections without making the reader feel like a chimp. Less successful are illustrated sections which are a bit vague; and now and then, (with an apologetic nod), he lost me with a sudden excursion into mathematics. In a rather modest touch the author lets us know when he is about to start the heavy mathematics, and assures us that he will be brief, but if you want , you can skip those sections with little lost.
In a smart and sensible move Mr. Bennet spends quite a bit of time not only explaining relativity, but also in defining, testing and proving its importance. Now and then his defense of the theories becomes a bit strident, as if he were a bit exasperated in defending relativity from attacks from many sides, but mostly he sticks to proving his facts, and standing by them.
All in all I recommend "What is Relativity" to all of us who are "Physics challenged". Hey Mr. Bennet, how about taking on Stephen Hawking next time?