Wednesday, 28 October 2009

Branches – Philip Ball ****

‘They are formed from chaos, from the random swirling of water vapour that condenses molecule by molecule, with no template to guide them. Whence this branchingness? Wherefore this sixness?’
This is Philip Ball, in his grand and mildly pompous style, describing how a snowflake forms. Branches (like this review) starts with concrete details rather than a general introduction. And the book (but not this review) starts as it means to go on: it has lots of examples and plenty of themes, but no thesis. But don’t let it put you off this rich, thoroughly-researched exploration of trees, rivers, bacteria, cracks, cities, and other kinds of branching growth.
The reason Branches lacks an introduction is probably that it is one third of a trilogy that Ball published as one volume back in 1999, and Branches has not quite disentangled itself from the other two books (see also Shapes and Flow). Ball often ‘reminds’ the reader of what they ‘learned’ in Book I or Book II. And the conclusion of Branches looks like it has been lifted straight from the 1999 volume, since it describes many ideas that do not appear in Branches. The promotional material on the back cover is also confused about the book’s identity. According to the blurb, Branches depicts nature as an ‘ever-changing, kaleidoscopic array of forms'; on the other hand, it is about the ‘deep elegance, simplicity, and unity of nature.’
So what is it, kaleidoscopic or simple and unified? The point is that it (nature) is both. And so is this book. On the one hand it deals with an impressive range of phenomena, from the natural (leaves, rocks, lightening) to the human (social networks, urban development); from the wondrous (snowflakes, lightening) to the mundane (opening an envelope, rain on a window, cracks on a mug); from the big (cities and rivers) to the small (bacteria and electric charges) and many things in between (trees, lungs, minerals in rocks). It does not deal with the very big (galaxies, black holes) or the very small (quarks, curled-up dimensions), but this is part of its charm: it finds pattern and excitement where we would not expect it, in the everyday world of middle-sized objects.
On the other hand Branches shows that each of these phenomena have something in common. As the book’s many illustrations tell us, they all look a bit like the branches of a tree, with a medium splitting repeatedly into two. And they also show (in Ball’s words) ‘a delicate balance of chance and determinism': rain falling randomly on a randomly rough surface gives rise to patterned river networks; weaknesses spread randomly through a piece of glass give rise to a predictable crack pattern. Many of them are also examples of fractals: each branch splits into two branches, which split again, and so on down the magnitudes. The shapes of many of the phenomena in the book can also be explained by a ‘minimization principle': a branching river network minimises the rate at which the water loses energy; the branch network on a tree minimises (according to some scientists) the length of each branch.
But these general ideas can only go so far. Ball is wary of becoming a fractal bore, someone who goes round collecting examples of fractals and putting them on display. The interesting phenomena are those that share a particular degree or kind of fractalling, and the remarkable thing is that the same degree or kind appears in completely different contexts: two different cities that show a different ‘fractal dimension’ are less alike than a city and a bacterial colony that have the same fractal dimension. As with fractals, so with the other general ideas in the book. The maximisation principle in animal veinous systems is different from that in the branches of a tree; chance and determinism have different roles in the formation of a glass fracture than in the formation of the Giant’s Causeway in Ireland. Branches is kaleidoscopic not just in its variety but also its intricate patterning.
Another unstated theme of the book is models. The main technical problem for the scientists in Branches is not detection and measurement but abstraction and simulation. A tree or crack scientist, unlike a quark or star scientist, does not have much problem getting in touch with their phenomena: trees and cracks are right here, and easily observed. The problem is that trees and cracks are devilishly complicated and disorderly phenomena, and the scientist wants to find two or three basic principles that explain how all the different kinds of trees and cracks form. Ball describes how scientists look for these principles using concrete models that slow down or scale down phenomena, like an artificial snow-flake that crystallises on a thread of rabbit hair, miniature mountains formed in the lab, and slow-motion cracks made by gradually lowering a plate of hot glass into hot water. But most of the models exist on computer programs or in equations, and these models are the real heroes of the book.
By giving us the essence of each model without writing down any programs or equations, Ball shows his own talent for abstraction. At one point (to take an example at random) he describes how models borrowed from physics can mimic the growth of cities. First he describes the model input, the basic picture a team of modellers used for a growing city: new developments appearing around a central hub, favouring areas have empty space nearby. Ball then gives the model outputs – pictures of cities generated by the model – and compares these outputs to present-day Cardiff. He describes how a new modelling team adds complexity to the model inputs, to account for the fact that new developments feed off existing, successful developments. The new model generates new outputs, which Ball again compares to a real-life example, Berlin this time. In this way Ball describes how a particular model works, and how model-based science works, without describing a single program or equation.
Ball’s prose is lively but sober, constrained by the gritty details of the science he writes about. But the phenomena are often vivid, and Ball has a sense of their poetry. Here he is describing how a sawtooth-shaped tear develops in a soft material like paper when a hard object is run through it:
‘So each crest of the cycloid, where the rip changes direction, corresponds to the switch from bending to stretching the strip. The crack swings constantly from side to side, at the same time surging ahead and then slowing down like the juddering stick-and-slip of a heavy object being pushed across a floor.’
Branches is at the serious end of popular science writing. You don’t need a physics degree to enjoy it, but you do need concentration. Ball (a physics PhD) has a practitioner’s interest in the details of science, and each chapter introduces a new crowd of scientists, models, and physical phenomena. Readers may find themselves flipping back to earlier chapters to understand ideas in the current chapter. They also may find themselves reading some chapters twice to retrace Ball’s zigzagging exploration of an idea, and the lack of clearly stated themes (or a working introduction or conclusion) makes it easy to get lost in the details. But if you are interested in science, nature, and how the former can explain the latter, this book is a superb study.
Review by Michael Bycroft

Wednesday, 21 October 2009

The Humans who went Extinct – Clive Finlayson ****

There are two ways to write a really good popular science book. One, the more common of the two, is to be a good writer, who can take your reader into the story of the science, and to be able to portray complex scientific principles in a way that the general reader can understand. The other is to challenge long held beliefs about a scientific principle and make the reader think ‘Yes, this makes sense.’ This can feel really exciting for the reader, as if you are part of discovering something new. Clive Finlayson’s book falls into the second category, and unlike many challengers of scientific theories (for example, those who regularly take on Einstein), he has the authority to get away with it.
It’s probably worth getting the two big hurdles to appreciating the book out of the way first. It’s quite often tedious in its ponderous plod through different environments and reactions of proto-humans and others to those environments. These parts could have done with some heavy pruning to make them more readable. And the book is rather light on the central topic. After all, the title suggests we are going to be reading about Neanderthals – and though one chapter is mostly on them, and they crop up repeatedly through the rest of the text, there was a real feeling of waiting for the Neanderthal bit to come, and never quite reaching it. The subtitle is more illuminating – ‘Why Neanderthals died out and we survived’ – with emphasis on ‘why we survived.’
It’s a real shame about those boring bits, because Finlayson can be very engaging, particularly when he relates a personal incident. However, it is worth ploughing through them for the good parts. Some of these are the bits where we do find out more about Neanderthals – now thought to be more like the picture on the cover than the shambling, heavy-browed monkey men we were brought up on. The other particularly powerful message is that Homo sapiens didn’t take over the world by pushing Neanderthals out through superior brain power. Instead it was more a case of the race whose way of life was more capable of fitting with the dominant climate, and able to be more flexible as climate changed, that survived. Finlayson emphasizes how much chance entered into this.
The result is a very different picture of the way modern human beings emerged from our ancestors to the one that has been the norm until recently, one that makes a lot of sense, emphasising how much this is a good popular science book of the second kind. And there are even lessons for the present, when climate change may again threaten the future of a particular human species. Our own.
Review by Brian Clegg

Monday, 12 October 2009

Nothing: a very short introduction – Frank Close ***

I came to this book for the title. Like “Zero”, “Symmetry”, or “Shapes”, “Nothing” is one of those concepts that seems to offer an intriguing cross-cutting view of science. A few pages into the book, I thought it would deliver on the promise of the title page. But after a couple of chapters I realised that this is a book about Something, not Nothing. A few chapters later it dawned on me that the Something was actually Basic Ideas in Modern Physics. Basic Ideas in Modern Physics is an interesting topic, but not nearly as novel and mind-bending as Nothing.
It’s not Frank Close’s fault that modern physics is preoccupied with nothing-related issues: what happened at the beginning of the universe, when something turned into nothing; how the very smallest particles (or waves) behave; the geometry of space and time. And if you would like to trot through the basics of fields, waves, special and general relativity, quantum theory, the Big Bang, and the structure of the atom, then this book is just what it says on the packet: a stimulating way into new subjects. But somehow I expected more from Nothing.
What is in the book for those who have already trotted through the basics with other science writers? Some old friends reappear – the falling muon to illustrate special relativity, the pencil-on-its-point to describe symmetry breaking. But Close also takes some new angles on the old topics. In general relativity, objects tend to take the shortest route between two points. Close compares this to the tradition of “shortest path” thinking in other fields, like optics. He notes how Einstein’s equations for special relativity are the same, mathematically, as those in Lorentz’s theory of the ether. And he has a good eye for historical details. It’s one thing to say how one might lay out a theory of special relativity. But how did Einstein himself do it, using what he knew at the time? Close has the question – if not the answer – at his fingertips.
But Close’s angles are sometimes too oblique. In explaining special relativity he starts out with the common-sense notion of simultaneity, and explains how it is defeated if we assume light is constant. He then jumps to the conclusion that objects must get longer, and clocks run slower, for observers of a moving object. It’s not clear how he made the jump. We see that Lorentz’s equations are the same as Einstein’s, but it’s not clear why they are the same. His chapter on the quantum vacuum is interesting, with some striking examples of experiments that cast light on the “infinite sea” of the vacuum. But the chapter has about three different arguments for different kinds of “infinite sea”, and it is not obvious how they link up.
Perhaps it was the small font or pocket-sized format, but I found it hard to get a proper grip on this book. It is a compact brainstorm. Close asks lots of questions, but it’s not clear when each one is answered. His no-fuss prose fits a lot in, but sometimes it’s too compressed. He throws out ideas – the anthropic principle, “emergence”, multiple worlds – that look promising but fall out of sight of the reader. By turns stimulating and frustrating, Nothing leaves you wanting to find out more about Basic Ideas in Modern Physics. Which is, after all, better than finding out about nothing.
Review by Michael Bycroft

Thursday, 8 October 2009

Eureka Man – Alan Hirshfeld ***

I was really looking forward to reading this book – Archimedes is a fascinating character whose work is usually under-appreciated, and I wanted to know more about him. Unfortunately, after reading the book cover to cover, I still know little more.
It’s not really Alan Hirshfeld’s fault. I had a similar problem when writing a biography of Roger Bacon – when looking back this far there is very little fact to be established about the life and personality of an individual. So you have to do something else. Give context. Talk about his work. Hirshfeld does this, but the way he approaches it didn’t work particularly well for me.
Quite a lot of the context aspect is given over to a potted history of Sicily in the period leading up to Archimedes life. I like history – but this wasn’t the most inspiring historical text, rather old fashioned in its concentration on rulers and battles. We had bits and pieces of Archimedes work – quite a lot, for instance, on his quirky little The Sand Reckoner, which uses the vehicle of working out the number of grains of sand it would take to fill the universe to show how the limited Greek number system can be expanded to handle vast numbers. There’s then a massive chunk – half the whole book – telling the story of the Archimedes palimpsest, where a number of Archimedes’ books, in Greek, some parts previous lost, were discovered under the pages of a prayer book.
This is a great detective story, but I think it’s better told in the book dedicated to it, The Archimedes Codex. Hirshfeld’s approach, as is much of the book, is a bit too breezy in tone and summary in feel.
If you want an overview of the significance of Archimedes’ work, and the context in which it was derived, this isn’t a bad book. And I have to emphasize again just how difficult it is to write biographically about a person that history has only left us legends about. Yet I was still disappointed.
Review by Brian Clegg

Wednesday, 7 October 2009

The Emperor’s New Drugs – Irving Kirsch ****

They say that the Origin of Species is “one long argument.” Irving Kirsch may not share Darwin’s eloquence, but in The Emperor’s New Drugs he shares his passion for persuasion. Thanks to its wide scope, smooth delivery, and mastery of the data, this book is about as persuasive as a popular science book can be.
“The belief that antidepressants can cure depression chemically is simply wrong.” So Kirsch claims. A claim like this raises a host of questions. Some are easy to answer: why would drug companies exaggerate the value of their pills in an anti-depressant market worth $19 billion a year? Why would regulatory agencies that are partly funded by drug companies play along with these exaggerations? Other questions are harder: if antidepressants do not cure depression chemically, how do they do so? And if the answer is “the placebo effect”, how can the placebo effect be so strong as to convince millions of patients, thousands of doctors, and dozens of editors, that antidepressants are more than just glorified sugar pills?
Some of the tough questions turn out to have simple answers. The reason everyone was duped by the chemical-imbalance theory of depression, says Kirsch, is that the theory itself was based mainly on the (supposed) effectiveness of chemicals in treating depression. Some answers rely on clever reasoning. Clinical trials show that antidepressants are actually more effective, by a small but significant amount, than placebos. Kirsch explains this deftly as an “enhanced placebo effect”: patients who detect the side-effects of antidepressants know that they are on active drugs, raising their expectations about the treatment and enhancing the placebo effect.
What all Kirsch’s answers have in common is thorough attention to the relevant data (published and unpublished) and a keen nose for interpretation. Kirsch marshals an impressive range of evidence to back his case: the bibliography runs to 25 pages and consists mainly in articles from top medical and psychology journals. If he does not have a study or meta-analysis to back up a claim, he says so. And he knows that a striking anecdote is just a striking anecdote, even if it punches for his own team.
The book a good first course in scientific method, and a key lesson in the Kirsch curriculum is that data alone does not put a hypothesis to the test. Data, plus a dose of careful interpretation, is the only real medicine in science. Drug companies did not falsify the reports of individual patients or doctors. Nor did they (usually) fudge individual studies. The devil was not in the details but in the grand design, the way they selected out negative studies and re-hashed positive ones. In lifting the lid on the cover-up, Kirsch gives a running response to those say that meta-analysis, as a scientific technique, is indefensible; nay, says Kirsch, it is indispensible.
The question every reader will have is partly an ethical question: given that antidepressants would no longer be effective if everyone knew they were only placebos, should the “dirty little secret” be made public? Kirsch, true to form, answers this question with a patient summary of studies and meta-studies. In doing this, he does not ignore the ethical core of the question. The aim is to cut through the empirical flesh to make the core issue as clear as possible. Kirsch shows that if you cut deftly enough, the core issue might not be ethical at all. This book asks: if we can show that psychotherapy is cheaper, safer, and more effective in the long run than anti-depressants, what ethical argument could possibly warrant the continued prescription of anti-depressants? Good question.
When it comes to writing clear prose, it is not always advantageous to be a scientist. But for Kirsch, it is so. He is no wordsmith (or doesn’t want to be), and if you are looking for blazing rhetoric then this not the book for you. But if you want to understand what a balanced-placebo test is and why it works, how neurotransmitters are meant to explain depression, and the difference between “response-rate” and “average improvement” in clinical trials, Kirsch is a lucid guide. His prose might read dryly for some. But the result is that if you can understand a bar graph, you can understand this book.
What Kirsch lacks in verbal charisma, he makes up for in arresting content. His chapters on the placebo effect make for fascinating reading. My favourite is the man who swallowed all his pills and collapsed in a heap on his GP’s floor – only to find, when he came round, that he had overdosed on fake pills. Equally striking are the basketball-players whose knee problems were fixed using placebo surgery, and the angina, dermatitis, and electro-shock victims who were all cured or assuaged by the power of belief. Kirsch describes lots of experiments designed to tease out the details of the placebo effect. The methods are clever, and the results run a skewer through our intuitions about physiological cause and effect. The results seem like voodoo, but the methods do not. As this book reminds us, implicitly but forcefully, it is the methods that matter.
Kirsch is sometimes not as methodical as he might be. One defence of anti-depressants is that they have both a placebo effect and a real chemical effect, but that these two effects are not additive. Kirsch describes how this hypothesis might be tested, but admits that no such tests have been done. He tells us that drug companies, who would otherwise sponsor such tests, are running scared. Fair enough; but the fact remains that the tests have not been done. Also, a bullet-point summary would be useful to tie up the threads of evidence against anti-depressants; sometimes the same thread turns up in widely separated chapters, making it hard to keep track.
Kirsch could do better to explain the weirdness of the placebo effect. How can the mind restore the cartilage in a bad knee just by expecting the knee to be cured? Kirsch suggests that this is easily explained as a purely physical causation, the brain acting on the knee. But it seems just as weird for the brain to cure cartilage as for the mind to do it. It also seems weird to say that the brain “expects” something. Lastly, it seems weird for positive expectations to have a positive effect. Why don’t positive expectations just make the brain more complacent, and therefore idle? Kirsch seems complacent about explaining the placebo effect, even if (or because) the evidence for its existence is overwhelming.
These quibbles do not threaten Kirsch’s argument. In the epilogue Kirsch says he enjoys “rocking the boat.” And the evidence suggests he has knocked antidepressants into the water. He reports a recent survey of UK clinicians showing that almost half will (or have) changed their practices because of Kirsch’s work. He has also made waves in the murky waters of drug regulation, helping to bring about proper tracking of drug trials. But he is a placid revolutionary, and his easy prose and wide knowledge make for a smooth ride – and a persuasive one.
Review by Michael Bycroft