The two most talked-about books in physics this year are probably a pair of anti-sting-theory books, Lee Smolin’s The Trouble With Physics, and Peter Woit’s Not Even Wrong, which shares a name with Jacques Distler’s favorite weblog. I got review copies of both, but Not Even Wrong arrived first (thanks, Peter), and gets to be the first one reviewed.
Of course, I’m coming to the game kind of late, as lots of other high-profile physics bloggers have already posted their reviews, and various magazine reviews have been out for months. Peter has collected a bunch of links in various posts. I don’t have a great deal to say about the book that other people haven’t said already.
There are basically two parts to this book: the first is a fairly breezy history of particle physics from the early days of quantum theory up to the present. The second part is the polemical stuff that you read on the blog. They take up roughly equal amounts of text, but the first part requires more effort to read, and the second part will sell more books.
(Further thoughts below the fold:)
The problem with the book is that it’s not terribly clear who it’s written for. The history of particle theory is very concise, but sort of difficult to follow if you don’t have at least a vague idea of what the Standard Model is going in. While Woit makes the admirable decision to avoid peppering the text with equations, he’s unable to avoid quite a bit of mathematical jargon:
The SU(5) GUT also had nothing to say about the Higgs particle or the machansim for vacuum symmetry breaking, and in fact, it made this problem much worse. The vacuum state now needed to break not just the electroweak symmetry but much of the rest of the SU(5) symmetry. Another set of Higgs particles was required to do this, introducing a new set of underdetermined parameters into the theory. Whereas the energy scale of the electroweak symmetry breaking is about 250 GeV, the SU(5) symmetry breaking had to be at the astronomically high scale of 1015 GeV.
All those terms are defined in the text, but even with that, it can be heavy going to get through some of the historical sections. And it only gets worse when string theory enters the picture. I’m not sure a lay reader would have any chance of getting through it, though for someone with at least a minimal knowledge of the state of things, it’s a nice sumamry of the history of particle theory. I’m just not sure how many people like that there are who will want to read the book…
The polemical part is an easier read, though bits of higher math crop up there, too. If you read Peter’s blog, you pretty much know what you’re going to get: string theory makes no predictions, it’s not even a theory, string theorists have an unhealthy dominance over the field of particle physics, etc. His basic case is laid out very clearly and compellingly, and without the petty sniping that often plagues the blog, and if you’d like a concise summary of the problems with the string theory enterprise, this is a good place to find it.
Those two parts are pretty good, as far as they go. The book could have been really excellent with the addition of a third part, providing a compelling alternative to string theory, or at least making a strong case for some alternative theory. Unfortunately, no such part is forthcoming.
That’s both an accurate description, and kind of depressing. As much as string theory appears to be chasing its own ten-dimensional tail, nothing else looks a whole lot better. Smolin’s book presumably will make a stronger argument for Loop Quantum Gravity (I haven’t read it yet), but Woit isn’t really a partisan of any particular alternate theory, which means he doesn’t have an alternative to push, and while he gives brief summaries of some alternative theories, he doesn’t make any of them sound terrifically compelling, either.
Which is kind of his main point, and a big part of his beef with string theory. None of the theories we have at the moment really work, and it’s kind of questionable whether any of them are even on the right track. Real progress may turn out to require dramatically new ideas, but it’s not clear that the current arrangement is going to allow that.
One interesting note, at least to me, was the suggestion late in the book that string theory should become more like pure mathematics:
Mathematicians have a very long history of experience with how to work in the speculative, postempirical mode that [John] Horgan [in The End of Science] calls ironic science. What they learned long ago was that to get anywhere in the long term, the field has to insist strongly on absolute clarity of the formulation of ideas and the rigorous understanding of their implications. [...]
To mathematicians, what is at issue here is how strongly to defend what they consider their central virtue, that of rigorously precise thought, while realizing that a more lax set of behaviors is at times needed to get anywhere. Physicists have traditionally never had the slightest interest in this virtue, feeling they had no need for it. This attitude was justified in the past when there were experimental data to keep them honest, but now perhaps there are important lessons they can learn from the mathematicians. To be really scientific, speculative work must be subject to a continual evaluation as to what its prospects are for getting to the point of making real predictions. In addition, every effort must be made to achieve precision of thought wherever possible and always to be clear about exactly what is understood, what is not, and where the roadblocks to further understanding lie.
This is interesting to me (and it always comes back to me, because this is my blog…) because I’m currently team-teaching an introductory physics course with a math professor. I’ve sat through three introductory calculus lectures in the last week, which have reminded me just how much time mathematicians spend on precisely defining terms. I always hated that as a student, which is why I’m an experimental physicist these days, but confronted with some of what’s going on in string theory (both Woit’s description, and some colloquia I’ve seen on the topic), I can sort of see the point.
Which brings me around to the third element that is present in the book (as opposed to the clear alternative theory that I would’ve liked to find): there’s a lot of excellent material in here about the interaction between mathematics and physics over the years. It’s been a troubled relationship, with each side taking a fairly dim view of the other for much of the history of modern physics, and Woit does a very nice job of describing the various falling-outs and reconciliations over the years as the two fields have moved apart and back together. This is largely orthogonal to the physics argument, but in some ways, the story of the interplay between theoretical physics and pur mathematics is the most interesting part of the book.
In the end, this is a fairly idiosyncratic book, with lots of different parts that add up to an interesting but fairly unique and personal look at the state of the field. I’m not sure I would consider it a definitive treatment of the field, but if you know a bit about particle theory, and would like to learn more about its troubled history, it’s a pretty good read.