swans on tea

This is late, and I have to apologize for that, but I finally got to finish reading Chad Orzel’s How To Teach Relativity To Your Dog. For my tardiness I blame the really nice stretch of weekend weather we’ve had, which “forced” me to do outdoorsy things with my disposable free time. (There’s also the issue of my bifocals, which make reading small-ish type somewhat uncomfortable, or I might have finished this one or two sittings)

Chad is a professor at Union College in Schenectady, NY (something I can type without looking it up, since I grew up in that area), has a background in atomic physics and writes a blog called Uncertain Principles. If you read my blog on a regular basis you should already know of him, since I link to his blog on a fairly regular basis.

I’ll get this part out of the way first: I am not a data point to confirm that this will help you understand relativity; I’m not really the target audience — I already have an understanding of relativity. I was happy to be offered a copy of the book for review, but I don’t normally buy mass-appeal (or books that aspire to be mass-appeal) physics books, because I already have a physics degree. But I can say this: I think it’s a valid approach, and it’s done fairly well.

The problem with mere textbooks is that they are usually quite dry, and pop-sci books often skimp on technical accuracy in trying to compensate to engage the reader. Chad has grabbed the middle ground in using the conversations with his German shepherd, Emmy (The Queen of Niskayuna) to both set up the discussions and to raise objections to the various conundrums that appear in learning about relativity. The dialogue format is helpful, because as anyone familiar with the topic knows, there are a lot of moments in learning relativity where the natural reactions is, “Whoa! That doesn’t make sense!” and this is pretty much what happens. (The only textbook I’ve read that uses a conversational approach is Electrodynamics by Griffiths, which is excellent) There’s a lot of dog dialogue (dogalogue?), and depending on your tolerance for the approach (along with some puns and pop-culture references) it might be a little much. There’s 300 pages of it.

Chad covers all the topics, starting with special relativity, including spacetime diagrams. Invariant quantities and E=mc^2 follow, and then general relativity, with all that entails, along with the ramifications of relativity in the form of cosmology and high-energy/particle physics.

The diagrams and equations are a necessary evil, but shouldn’t scare you off if you find them intimidating, because there’s plenty of discussion, and no problems to work. The satisfying part for me was that the level of technical accuracy is quite good (which is not at all surprising) even at the level where it probably wouldn’t matter to the casual reader, but things I would pick up on, especially in discussing clocks. In fact, I think my only technical nit was when he discusses energy holding nuclei together (forces hold things together) but in the context of the depth of the discussion, I understand the approach.

All in all, a pretty good book, and something a science enthusiast would probably find to be a worthwhile read.