Monday, 9 April 2012

Book Review: Cosmology: A Very Short Introduction

This is the first book I've read from Oxford University Press' A Very Short Introduction series. Launched in 1995, there are now over 300 in the range covering topics as diverse as Advertising and Wittgenstein, Christianity and Witchcraft. Each volume is reassuringly thin which must make even the more daunting topics seem accessible even before one starts reading.

The book on Cosmology is written by Professor of Theoretical Astrophysics at Cardiff University, Peter Coles. His previous works include textbooks on the subject as well as popular science books on both Einstein and Stephen Hawking.

A Very Short Introduction to Cosmology is not the same as Cosmology Made Simple - a trick I imagine it would be impossible to pull off, even if this were the intention. Instead it takes a systematic approach to explaining the development of Cosmological thought through history and of Cosmology as a subject in its own right. It then moves on to explain the concepts that underpin our understanding of the universe (with understandable emphasis on Einstein) before explaining some of the problems presented to the current models in obtaining data (and, indeed, by some of the observed evidence) and some of the proposed solutions.

Central to the book is the Big Bang, which Coles is at pains to talk of as a Model, rather than a Theory. The difference being that theories should be self-contained whereas models can contain variables. Given that the normal laws of Physics seem to break down at the temperatures and high-energy states anticipated by the model, there are a great deal of variables and this seems a suitably cautious approach. Cosmologists cannot be dogmatic.

Indeed, Cosmological thought has a number of inherent uncertainties - not just those caused by the lack of visibility of the first moments of the universe but also those ingrained in Quantum Theory by the Heisenberg Uncertainty Principle. This is the principle that if you know the position of a particle, you cannot know its speed and vice-versa. The same can be said of the relationship between energy and time.

The book tackles the uncertainty principles - along with concepts such as wave-particle duality -  with aplomb in short straightforward paragraphs that help build the reader's understanding bit by bit. Care is taken in explaining the more abstract concepts so that, even if these remain opaque to the lay-man, the issues they raise are clear.

The last chapter seeks to sum up the current state of play as well as to examine the challenges which face Cosmologists. The hope is to achieve a unified theory that will explain the observed evidence and overcome some of the problems in our current understanding. In particular, this will involve uniting our understanding of Gravity with the other fundamental forces - the Electromagnetic and the Weak and Strong Nuclear forces.

Overall, this is a great primer on one of the more challenging areas of human understanding and thought. I felt I understood the concepts as the were presented (although I may have struggled with the retention of multiple concepts, as the book went on.) Having read Simon Singh's Big Bang and Hawking's Brief History of Time (as well as seeing the ubiquitous Brian Cox on telly), some of the material was familiar. Singh's book is, perhaps, an easier read but this is a more rigorous and expansive explanation of the topic. If you're at all interested in the origins of the universe, you could do worse than start with this book.


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