From a long view of the history of mankind – seen from, say, ten thousand years from now – there can be little doubt that the most significant event of the 19th century will be judged as Maxwell’s discovery of the laws of electrodynamics.

Richard Feynman Physicist

Brian Clegg

Asked to name a great physicist, most people would mention Newton or Einstein, Feynman or Hawking. But ask a physicist and there's no doubt that James Clerk Maxwell will be near the top of the list.

Maxwell explained how we perceived colour. He uncovered the way gases behave. And, most significantly, he transformed the way physics itself was undertaken in his explanation of the interaction of electricity and magnetism, revealing the nature of light and laying the groundwork for everything from Einstein's special relativity to modern electronics.

Along the way, he set up one of the most enduring challenges in physics, one that has taxed the best minds ever since. 'Maxwell's demon' is a tiny but thoroughly disruptive thought experiment that suggest the second law of thermodynamics, the law that governs the flow of time itself, can be broken.

This is the story of a groundbreaking scientist, a great contributor to our understanding of the way the world works, and his duplicitous demon.

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A superb new biography of one of the greatest scientists of the 19th or any other century… The demon "acts as an intermediary between Maxwell himself and the reader. And he's a good enough writer to pull it off… This all adds up to a superbly entertaining biography that doesn't underestimate its readership. 'Professor Maxwell's Duplicitous Demon' is a substantial and thought-provoking read, light years away from those irritating books that simplify high concepts in the name of popular science. It's also a good-natured and, at times, fun read… Brilliant stuff. - Nick Smith, E&T Magazine

Brian Clegg would have it the his short, charming scientific biography of the Victorian Scottish physicist James Clerk Maxwell is not his own work, but
a collaboration with Maxwell's demon… Clegg reveals with a conjuror's confidence how Maxwell moved 'from simply explaining observations through mathematics to building mathematical models that took on a life of their own.'… Clegg's huge backlist of popular science covers everything from quantum entanglement to climate change… he's one of that curiously egoless cohort of excellent writers who quietly, steadily run rings around their flashier peers. Clegg doesn't make science delightful. He delights in science. It shows. - Simon Ings, The Spectator

Do you love physics? Want to know more about the scientist who changed our understanding of light and their demonic thermodynamic thought experiment? 👹 a new book by @brianclegg on the life and work of James Clerk Maxwell is out now and it’s really great 👍 - Paul Coxon, University of Cambridge via Twitter

Brian Clegg has done a wonderful job here of recounting just what Maxwell achieved – and how he went about it, and why it puts him on a par with the other greats… The book’s most unusual feature is hinted at in the title. Clegg brings the demon to life, allocating something like a fifth of the total page count to first-person ‘demonic interludes’ – providing background-filling flashbacks and flashforwards – supplemented by copious footnotes on the main chronological narrative. The demon’s writing style is a slightly more whimsical version of Clegg’s own, so the overall effect is rather like the author putting on a demon mask and continuing to speak in his own voice. That would be an entertaining way to lighten a heavy subject in a public lecture, and it’s just as effective here… The focus isn’t so much on the details of Maxwell’s work, as on how he went about it and how his mind worked. The result is a fascinating read… The ones who pick this book up are likely to come at it with at least some awareness of Maxwell’s existence – and a curiosity to learn more about his life and work. And they won’t be disappointed. Andrew May, Popular Science book review site

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