Book Review: Gravity by Brian Clegg

Clegg, Brian.  Gravity: How the Weakest Force in the Universe Shaped Our Lives. New York: St. Martin's, 2012. Hardcover. +336 pages. $25.99.  Release date: 22 May 2012.

Full disclosure: I received a digital advance copy of this book from the publisher for review.

Gravity is one of those books that is trying to do two things and doing neither very well.  At once, it's attempting to be a history of gravity as we know it and to explain gravity as well as possible in layman's terms, but reading through it, I found it a huge disappointment on both sides.

This is partly because of the organization.  Clegg jumps around from historical ideas to explanation with little to no transition.  I'm not sure that there would have been a better way to organize the book--after all, one must understand Newton before one gets to Einstein, but it's not well done.

I think the largest problem is that Clegg is not a historian of science, and I'm inclined to think that he had a bad experience with one somewhere in his career--either that, or he is one of those unfortunate souls who got to college, realized that things did not work the way he'd been told in high school and has continued to resent it the rest of his life.  Most of the beginning part of the book is correcting misconceptions from high school science and history, which I truly have no problem with.  After all, Clegg does address the fact that the Greeks and the medieval world knew that the world was round, for example.  He points out that Christianity and Islam in the Middle Ages did not repress science, but encouraged it, and he points out that the medieval world, while not yet at the point to recognize that the earth was not the center of the universe, did realize that the earth rotated.

Yet at the same time, Clegg's also correcting things that really don't matter.  No, according to the Gregorian calendar change, Galileo did not die the same year Newton was born.  But does it really matter?  And is the brief digression into Latin philology necessary?  And Clegg makes assumptions about the feelings of scientists without any evidence for them, sending him into one-sentence flights of fancy that is incredibly distracting from the rest of the text.  The same thing goes for a brief discussion about the inside-out nature of anti-space and his completely gratuitous mention of Galaxy Quest, without any real meat to the analogy.

Clegg is best at underscoring some of the newer developments, such as Horava Gravity, which he claims may, if future experiments work out, may someday reconcile Newtonian physics and general relativity.  These are relatively new developments, which I'd not heard of.  Granted, while I am an English professor, the history of science is one of my specialties, and I'm by no means ignorant of much of what he's saying.

One section which really bothered me was Clegg's digression regarding the rubber sheet analogy.  Oftentimes, physicists use the rubber sheet analogy to explain how space-time is warped by gravity.  Here's an illustration from Stanford (from an article about Gravity Probe B, which Clegg does discuss in the book) that might help explain.

If you want a really useful explanation, I'd click through to the article.  But the point is that everything with mass distorts space-time around it.  This is an example of it simply in one dimension.  But Clegg has problems with it, because in this illustration, if we pretend the probe in the picture is a marble rolling around to the center of the well, we forget that there is also a little distortion around the probe.

Clegg's point is not that this is necessarily wrong, but that it's overly simple--we forget that it's distorting space-time, not just space.  That's all well and good, but the digression wasn't necessary.  Clegg could have made the point without the need to attack the model. 

And I suppose that's the real problem with this book.  Clegg is constantly on the offense, either against bad history, bad illustrations, bad politicians who are cutting money from projects, and bad scientists who are letting them.  His explanations aren't clear, and the book itself would be immensely improved by illustrations for visual learners. 

All in all, if you want a good explanation of gravity and the way quantum mechanics may work with relativity, go read Brian Greene's The Elegant Universe or watch the NOVA series.  It may not be as up-to-date as Clegg's, but you'll learn more and you'll learn it more easily.

Gravity- D+