10 Short Lessons in Time Travel - Brian Clegg ***

Time travel, as Brian Clegg reminds us in his first chapter (sorry, first lesson), was a popular fictional subject long before it found its way into mainstream science. That it did is largely thanks to Einstein’s theory of general relativity, which is a notoriously abstruse area of modern physics. So it’s no easy thing to produce a popular-level book that really gets to grips with the serious science of time travel, and it’s to Clegg’s credit that he achieved just that in his brilliant How to Build a Time Machine (aka Build Your Own Time Machine) ten years ago. This new book is rather different, approaching the same subject in an altogether more lightweight way.

Appropriately enough, it’s part of a series called ‘Pocket Einstein’. But the fact that Einstein keeps cropping up in it  – with topics like quantum entanglement and Einstein-Rosen bridges as well as relativity – is largely coincidence. Other titles in the same series include Artificial Intelligence and Renewable Energy, which aren’t subjects Einstein had much to say about. Of course, ‘Einstein’ is just publisher’s shorthand for ‘advanced science’ – and the inclusion of his name on a book’s cover is a pretty good indicator that it isn’t going to be very advanced at all. If Clegg really had devoted all ten lessons to the physics of time travel it would have entailed far more technical detail than the casual reader is going to want, so some chapters take quite meandering – though always interesting and entertaining – detours into very loosely related subjects like space drives and suspended animation.

I realise that a book like this is built around a title the publisher thinks will sell, but I still feel it would have been better as ‘10 Short Lessons on Time’, with only two or three chapters at the end on actual time travel topics like closed timelike curves, wormholes and all the associated paradoxes. This would allow earlier chapters to focus squarely on other aspects of time without pretending to be about time travel. Not just other areas of physics, such as entropy and time dilation, but topics like psychology (our highly subjective experience of time) and philosophical musings from Zeno and St Augustine to the present day, are fascinating enough to warrant chapters in their own right. Clegg does cover these areas, but in a slightly apologetic way as if he’s saying ‘Don’t worry class, we’ll get back to our time travel lesson just as soon as I’ve finished this brief digression ...’.

If you happen to see this book when you’re looking for a relaxed but thought-provoking read, then don’t hesitate to buy it as it’s guaranteed to keep you entertained. But if you want a really thorough insight into the science of time travel, with copious endnotes that you can to dig deeper into, then Clegg’s first book is still the place to go.

Hardback: 

Bookshop.org

  

Kindle:  

Using these links earns us commission at no cost to you

Review by Andrew May

Please note, this title is written by the editor of the Popular Science website. Our review is still an honest opinion – and we could hardly omit the book – but do want to make the connection clear.