July 11, 2013


The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality. By Dave Goldberg. Dutton. $27.95.

     Physicists have better senses of humor and are pithier in expressing their views than most non-physicists realize. Some physicists, anyway. The oft-quoted Einstein remark that “God does not play dice with the universe” led Niels Bohr to snap, “Stop telling God what to do.” And Stephen Hawking has delightfully commented, “A tiny disturbance in one place can cause a major change in another. A butterfly flapping its wings can cause rain in Central Park, New York. The trouble is, it is not repeatable. The next time the butterfly flaps its wings, a host of other things will be different, which will also influence the weather. That is why weather forecasts are so unreliable.”

     So Dave Goldberg, physics professor and director of undergraduate studies in physics at Drexel University in Philadelphia, comes by his irreverence honestly. And delightfully. The Universe in the Rearview Mirror is about the many ways in which, despite the apparent disorder of things, there is underlying symmetry to many processes that is crucial for understanding them – and for making sense of the universe and, not coincidentally, ourselves. This may seem like dry, heavily mathematical stuff, and it is just that for many scientists studying our universe, but not for Goldberg and therefore not for the lucky readers of this book. Just check out the footnotes: in one, Goldberg mentions the particle called a kaon and then offers “a kaon koan: What is the sound of a subatomic particle turning into its antiparticle?” This is typical of his writing: introduce complex subjects, explain them clearly, and then have some fun with them so readers will find them intriguing rather than off-putting.

     A great deal of this book takes off from or is built around the work of Emmy Noether (1882-1935), a hugely important mathematician who, when not making breakthroughs in theoretical physics, was making them in abstract algebra. Noether’s Theorem specifically and elegantly explains the fundamental relationship of symmetry to laws of conservation – and it is a pleasant irony of the English language (despite the fact that Noether was born in Germany) that her name can be broken up into “no ether,” meaning the so-called “fifth element” of early physics, the material supposed to fill the universe above the terrestrial sphere, does not exist. “Emmy Noether Threatens to Overthrow All Academic Order,” says one subhead of a chapter here, and indeed Noether’s theorems – which are elegant in their simplicity and mind-boggling in their implications – were as challenging in their way as Einstein’s.

     Actually, simply reading Goldberg’s subheads is a great way to start this book – before coming back and finding out what he actually says in the sections. “How Einstein Fixed Galileo.” “Why You Can’t Have an Ansible” (the famous science-fictional device that communicates instantaneously across interstellar distances). “Life in Antworld.” “Seriously, Are Black Holes Really Black?” “An Exceptionally Simple Theory of Everything.” Goldberg does not have all the answers to the questions he poses – neither does anyone else – but he poses them in such a direct, even charming way that readers will find themselves considering things in all seriousness that they may only have thought about before in passing, if at all. (Example: why don’t atoms explode?)

     “The universe isn’t quite as obvious as it might seem at first,” Goldberg notes, and in many ways this is the core information in this book. Goldberg, who has a touch of the showman about him, cannot resist offering one example, just one, of how the universe is different from what we might expect: he presents a simple experiment called Feynman’s Plate in which the reader, armed only with a glass of water and an arm, gets to find out that a 360-degree turn, which should bring things back where they started, only gets them halfway there.

     This is simplified physics, but readers should not expect it to be entirely simple, and certainly not simple-minded. Goldberg writes plenty of sentences like this one: “The Higgs mechanism was concocted to explain how it could be that the W and Z0 bosons had mass even though none of the other mediators do.” But Goldberg is always scrupulously fair in explaining his terms and, to the extent possible, presenting highly abstruse mathematical concepts in straightforward English. That this is not always possible is scarcely his fault. The Universe in the Rearview Mirror is a fascinating book about a fascinating subject – life, the universe and everything – and Goldberg is a simply wonderful guide to and through all the thickets of complexity and obscurity that one encounters along the road of trying to understand what makes everything tick. Rather than, say, tock.

1 comment:

  1. Thank you so much for your kind words. I'm so glad you enjoyed the book. I only have one quick correction, and that is that I'm the Director of Undergrad Studies in Physics, not the Department Chairman. (I appreciate the promotion, but perhaps not the increased headaches).


    - Dave Goldberg