Skip to main content

How Many Licks? – Aaron Santos ****

Author Aaron Santos takes on the rarely considered but entertaining job of solving Fermi problems: making back-of-an-envelope estimates of numbers that range from the trivial, like the number of licks need to reach the centre of the lolly in the title of the book, to questions like ‘How many babies are born every day?’ The full title is ‘How many licks, or how to estimate damn near anything.’
I thought this might prove a bit samey after a while – there are 69 problems in all, ending in estimating which uses more silicon in the USA, computer chips or silicone implants (I know silicone isn’t the same as silicon, but it does contain it). In fact, each time I wanted to turn on and get to the next one.
The more enthusiastic may want to try to work out some of these as they go along. I was happy to take Santos’ word for it and just enjoy the ride. I do occasionally do this sort of thing for real, but I didn’t particularly want to do so for the problems cited here.
If there’s any complaint it was a slight inconsistency in deciding whether or not to make the assumption that ‘the United States of America’ and ‘the world’ are the same thing (this is, if assumed, not a great piece of estimating on the author’s part). So, for instance, when answering ‘How much deforestation would result each year if people chopped down their (Christmas) trees from a forest rather than getting an artificial tree or getting one from a tree farm?’ the question appears to apply to the whole world, but Santos bases his estimate of ‘How many people get real Christmas trees each year?’ on a percentage of the US population.
That apart, it was fun all the way. The book appears to have been professionally published, though it does rather have the feel of a self-published volume – it’s a little flimsy and unusual in the layout – but seems to have been properly edited and the illustrations and formulae are neatly done.
All in all an enjoyable gift book, or some light reading if you like the idea of playing around with estimating… or just want to be surprised how relatively easy it is estimate some surprisingly obscure numbers.
Paperback:  
Review by Brian Clegg

Comments

Popular posts from this blog

The Demon in the Machine - Paul Davies *****

Physicists have a habit of dabbling in biology and, perhaps surprisingly, biologists tend to be quite tolerant of it. (I find it hard to believe the reverse would be true if biologists tried to do physics.) Perhaps one reason for that tolerance is Schrödinger’s lecture series and book What is Life?, which had a huge impact on molecular biology and with a reference to which, not surprisingly, Paul Davies begins his fascinating book. 

At the heart of the The Demon in the Machine (we'll come back to that demon in a moment) is the relationship between life and information. In essence, Davies points out that if we try to reduce life to its simple physical components it is like trying to work with a computer that has no software. The equivalent of software here is information, not just in the best publicised aspect of the information stored in the DNA, but on a far broader scale, operating in networks across the organism.
This information and its processing gives life its emergent compl…

The Cosmic Mystery Tour – Nicholas Mee ****

This is another book, like last year’s Enjoy Our Universe by Alvaro de Rújula, that sets out to provide a light-hearted introduction to physics and astrophysics for the general reader. It’s from the same publisher (OUP) and packaged in the same way: as a high quality small-format hardback with 200 glossy pages, the majority of them adorned with colour pictures. But that’s where the resemblance ends. Unlike its predecessor, this new book by Nicholas Mee delivers exactly what it promises.

It’s not that de Rújula’s book was a bad one, but he just wasn’t able to think his way into the reader’s mind. He kept saying ‘physics is fun’, but he was talking about the fun a professional physicist gets out of doing it – which is a very arcane, often highly mathematical, type of fun. The result, for a non-specialist reader, was actually quite alienating. Mee, on the other hand, understands exactly how his readers think, what they find interesting, and the details that – no matter how important they …

Professor Maxwell's Duplicitous Demon - Brian Clegg ****

‘It’s not uncommon when trying to give Maxwell his rightful place in the pantheon of physics to bracket him with Newton and Einstein’, Brian Clegg says towards the end of this book. In one sense that’s perfectly true. Dip into any physics textbook and you’ll see Maxwell’s name at least as often as the other two. His greatest achievement – Maxwell’s equations – did for electromagnetism what Newton had done for gravity, while laying the essential theoretical groundwork for everything Einstein was to do.

There’s a big difference, though. A few years ago, when I was offered the chance to write short biographies of Newton and Einstein, I jumped at it – because they addressed mysteries of the universe that anyone can relate to, and their lives outside physics were, if anything, even more fascinating. At the risk of sounding downright rude, you can’t say either of those things about James Clerk Maxwell. In spite of that, Brian Clegg has done a wonderful job here of recounting just what Maxwel…