Sunday, August 26, 2012

Book review: G. Schilling's "Higgs - Een elementair abc over een elementair deeltje"

A few weeks ago Govert Schilling invited people via his twitter account to review his new Higgs book in Dutch. Yes, in Dutch. (The cover is shown on the right, taken in a book shop in Utrecht.)

Schilling has been popularizing science (particularly astronomy) to the Dutch public for a long time, and besides writing articles in news papers and magazine, also wrote a long list of books. Just that? No. He is a very active user of twitter, and for a while was very active by popularizing scientific concepts in a number of tweets, he called a twursus, mashing up the Dutch 'cursus' (which mean course) and tweet (of twourse). These, inter alia, have been bundled as a book called Tweeting the Universe: Very Short Courses on Very Big Ideas by Chown and Schilling.

But this popularizing in Dutch is actually of utmost importance for the level of science in The Netherlands. It always annoyed me the advantage native English speakers have in Science. Don't you wish those university rankings where compensated for that?

So, when you send out that invite, I was eager to read his book on the just discovered Higgs boson. Physics was my best topic in secondary/high school, but found chemistry to have a better complexity (or, physics was too simple). Yet, since second or third year at the university I had not done much to keep up with new things in physics. Another aspect of my interest is, of course, my own recent book writing, and measuring that up with a book by an experienced science writer like Schilling. But I underestimated the work it would take, and the review below explain why that is the case.

The book sets out with introducing us to the language of nature. This was light reading for me, as a natural scientist, and having read books on quarks, gravity, and relativity before. Some basic chemistry is discussed too, for example by outlining how the number of protons defines the element. Isotopes are skipped. From there on, it moves to quarks and the standard model. Compared to what I have read about quarks some 20 years ago (a Dutch translation of a book by Gell-Mann), the field has moved on, and one speaks now of many types of flavors, with different properties.

Comment 1: And that gets me to one downside of this book: it features only few graphics. As someone who like to works with patterns, visualization is a rather helpful tool. Instead, the book is mostly text-oriented. Yet, this is easy to fix in future editions of the book. (I understood the book is already in a second print.)

It also gets me to a second problem, but that is more of a problem for me, than of the book: I have prior knowledge, a bit outdated, a bit from a different field, and found it very hard at occasions to relate the material presented to things I know, or think I know. Some of my confusion I discussed with the author over Twitter (#twitpubinnov), such as that the Higgs field is something different than the gravity field, even though the Higgs field (or particle) gives matter mass. So, there is something that gives things mass (the Higgs boson), and something that makes things with mass interact (the graviton). And linking that the further prior knowledge: it is like there is a field that gives electrons charge, and the electric field that causes charged particles to interact. But, but... hence my headaches.

Comment 2: It is hard to find a pattern in the many fields. While Schilling gives a clear overview of all particles, and while he also hints at particle/wave duality and also mentions that the Higgs particle is like a ripple of the Higgs field (a particle/field duality?), I remain with many questions around these aspects of current physics knowledge.

The book then continues as a kind of dictionary or encyclopedia, coverting the topics atlas, boson, CERN, dark matter, energy, fermion, graviton, Higgs particle, interaction - yes, the Dutch words are *very* similar -, J/PSI, forces ("krachten"), lepton, mass, neutrino, discovery ("ontdekking"), Peter Higgs, quark, renormalisation, sigma, theory, universe, field ("veld"), competition ("wedloop"), and gravity ("zwaartekracht"). These chapters are easy to read, but have the tendency to lead to more questions. This is covered to some extend by cross-linking between chapters, but I think the learnability can be improved. In blog posts we do this by adding hyperlinks, as I just did in this and the previous sentence. Of course, the paper nature of this book is not very helpful.

There are also a number of more specific things I like to point out. Some are because I like to learn more, others because I am not sure I fully understand what Schilling wanted me to pick up. For example, the chapter on energy has an analogy of the energy of the Higgs boson (~ 125 GeV) and indicates that is about the same energy matching the mass of a gold atom (presumable via the omnipresent E = m c2. My immediate question was, that if the Higgs boson has that much energy (or, is that 'heavy'), how can it give mass to something as light as an electron?

Comment 3: the book is writing speaks physics, and is harder to read for other natural scientists. For example, the book writes that the mass of the electron is so small compared to that of protons, that it can be ignored, but in biology and chemistry it is far from that, and very important in the field of mass spectrometry. Of course, both are true, depending on the field of research you are looking at.

Some things I tend to disagree with. Not on the physics, where Schilling outranks me by orders of magnitude. I do question a statement as that made in the first paragraph on the leptop. The text reads that "only at the end of the 19th century scientists start wondering if there are smaller particles than atoms". I don't buy that. I am sure they wondered about that before; just like we wonder what the particles are that constitute quarks, and why I want to understand biology at an atomic level. Did no biologist wonder if gene-protein is not a simple one-to-one relation before that dogma was overturned some 10-20 years ago? Did not biologist wonder what further mechanisms exist in gene regulation?

Instead, what happened at the end of the 19th century is that people started being able to convert that intuition, that curiosity into testable questions. And that relates to the text on theory, where Schilling writes that theories do not have a timeless truthfulness, citing Newton's gravity law. But with all that discussion about "only just a theory" where that chapter starts out with, in particular since he pulls in evolution theory, I think it misleads the author. What the text does not outline is that some theories have shown to be false, like the flat earth, while other theories just have a limited scope, like Newton's gravity law. Newton's law is perfectly valid, given a certain context.

This is actually in important issue, that bites many current discussions, for example, in ontology development, where you can find that some ontologies conflict with other ontologies, despite both of them being true. But I will have to write more on that at some other occasion :)

Comment 4: some analogies make the matter only more complex.

The book extensively uses analogies to 'visualize' the concepts. The book starts with with the analogy of a language, and later switches to other analogies. For example, in the chapter on quarks, the interactions of quarks are explained as interactions by humans. But I have the feeling that comparing baryons to threesomes of three guys or two Swedish women and an Irish lady is distracting at most. I would have preferred to stick to the language analogy.

The sigma has popped up on the internet often, in relation to the Higgs boson, which I found rather confusing at the time. Was this the statistical sigma, typically estimated to get a feel of chance distribution in measurements? But what does the "five sigma" refer to then? Obviously, the measurement of the Higgs particle's mass is not five sigma away from the theoretical value. So, what is it then? Unfortunately, Schilling's book does not make it much clearer, but at least it confirms that the sigma refers to the statistical one. He writes that the 'five sigma' is a community agreement on the significance of a experiment in natural sciences. I guess I missed something in my statistics PhD at Radboud University, because I had not heard about it before.

This ties in to the lack of learnability of the paper book medium: you do not want to give too much detail, because you loose the reader in the one dimension you have: from left to right, top to bottom (at least in English and Dutch). Webpages like this add dimensions, primarily via hyperlink. I have still to explore how the standard deviations of measurements can be statistically linked to the chance that that measurement reflects randomness in your experimental set up. The further reading at the last page do not do justice to the amount of curiosity triggered by this book.

And that is both the power and importance of this book: you want to know more.

The book is easy to read, provides a lot of pointers around the just discovered Higgs boson. This whole discovery outlines perfectly what science is about: we make models (I prefer that terms over theories) that describe experimental results and predicts the outcome of future experiments. That core aspect of science must be communicated more often and as early as possible in the education of people (kids). That is why I am so happy that Schilling writes so many works in Dutch.

I can highly recommend all secondary schools in the Netherlands (and other countries speaking Dutch) to buy this book. I also hope that future editions of this book will be extended with both graphics and with pointers to further reading after each individual chapter, but that must not stop you from getting a copy now. The price (~8 euro) won't stop you either.