Go on – guess!

For many of us in the Physics World office, the chief attraction of stumbling across an intriguing numerical factoid – the total energy required to air-freight a tonne of oranges across the US, say – is that it immediately turns into a guessing game, as we invite colleagues and friends to estimate the correct answer. If you are also partial to this kind of quick calculation, then you will surely enjoy Guesstimation 2.0: Solving Today’s Problems on the Back of a Napkin. Written by Lawrence Weinstein, an experimental nuclear physicist from Old Dominion University in Virginia, it treads the same path as his earlier book Guesstimation (see July 2008 p43). In the current volume, Weinstein poses a series of 70 or so numerical questions and invites the reader to make an educated guess at the answer – with help, if needed, from some gentle hints. Questions range from the simple (What is the total length of toilet roll used in the US each year? How many popcorn kernels would it take to fill a cinema?) to the complex, such as comparing the energy efficiencies of different forms of lighting. Weinstein does an admirable job of giving full and clear answers, always concentrating on making sensible estimates rather than striving for absolute precision. The final chapters of the book contain some quite advanced questions that will test even seasoned physicists. How closely, for example, could we safely orbit a neutron star if we considered only gravitational effects? (About 1000 km.) And what must the minimum possible lifetime of the proton be, such that radiation from proton decay will not kill us? (Some 10¹⁷ years.) Weinstein’s strong US-centrism and fondness for footnotes aside, this book will be perfect for all physicists wanting to give their minds a good workout.

• 2012 Princeton University Press £13.95/$19.95pb 377pp

A celebration of physics

So you want a popular-science book that encompasses our entire state of knowledge of fundamental physics, is technically correct yet also short and easy to read? Then The Universe Within by Neil Turok, director of the Perimeter Institute for Theoretical Physics in Waterloo, Canada, is for you. Based on the Massey Lectures that Turok gave in November 2012 on CBC Radio, the book races through the “standard history” of physics – from ancient Greek scholars to Einstein – before romping through quantum theory, cosmology and recent attempts to unify physics. It is all familiar territory, but whereas lesser authors might have got bogged down in details, Turok stays lucidly on track, drawing on his own experiences at Princeton University, Imperial College London and the University of Cambridge, collaborating with the likes of Stephen Hawking. The technical level is nicely consistent – there are no wild lurches up or down – and Turok’s prose is measured and even. However, the final chapter, which seeks to remind us of the power of scientific thought in tackling society’s ills, is a rather curious affair. Its strange conclusion – if there is one – is that we face a bright future because humans will derive “great mutual benefit” from quantum computers as both are analogue devices. (Classical computers, in contrast, provide digital information – which, Turok claims, is “evolutionarily regressive” for some reason.) The last chapter also has a few silly errors – South Africa didn’t “win the competition” to host the Square Kilometre Array (it will host the radio telescope jointly with Australia), while Paul Dirac studied engineering at the University of Bristol, not Cambridge. Unfocused ending aside, the rest of the book is first rate and highly recommended.

• 2012 Anansi £9.96/$15.95pb 294pp

Rolling in the deep

Most of us have been to the beach and seen waves rolling up the shore line. We may even have idly wondered where such waves come from, how they form and how they travel. But how much do we really know of the science behind their evolution? In Waves, author Fredric Raichlen takes an in-depth look at all of these topics, flowing easily from the mechanics of how water waves are born, through the way currents travel across the Earth, to the effects of wind, astronomical tides and the formation of tsunamis and hurricanes. An expert on coastal engineering and wave mechanics at the California Institute of Technology, Raichlen was inspired to write the book after recalling the questions his sons asked him about waves as they sat on a beach many years ago. A compilation of the answers would, he decided, help others with similar queries. The book is interspersed with interesting titbits, such as the fact that tsunami waves – the lengths of which are typically about 100 times their depth – travel at average speeds of “about 700 km per hour – the speed of a jet plane”, which is a neat way of conveying their might and destructive power. Later in the book, Raichlen also explains how a ship 300 m in length can be displaced by the action of waves that may be less than 1 m high – even to the point where the lines mooring it to a dock can be snapped by the wave action. However, the book is quite technical in its content, with a fair number of formulae and graphs. The language is also rather formal, making Waves feel like a textbook despite its slick cover and handy “pocket book” size. But if you want a quick reference guide to the nitty-gritty of water waves rather than a casual beachside read, this could be a handy addition to your bookshelf.

• 2012 MIT Press £9.95pb 232pp