Professor Maxwell’s Duplicitous Demon
By Brain Clegg Icon Books, 304pp, £16.99/$25
Names like Albert Einstein and Isaac Newton spring easily to mind but while we recognise James Clerk Maxwell as a scientist of importance, what he actually taught may elude many of us. That could be because his work was essentially to demonstrate that magnetism, electromagnetic radiation and light were all aspects of the same phenomenon. His famous equations expressing this in algebraic mathematics became the key to many of our modern developments.
Unfortunately, complex equations do not stir the blood of most of us and a central purpose of this book is to explain his achievement in the development of physics – second only, it is claimed, to Newton and Einstein. His work played a foundational role in matters such as radio waves, special relativity and quantum mechanics.
But this is not a textbook, it is a biography, and thus Brian Clegg introduces us to an interesting and humane man. Here we read about the real Maxwell, living within the 19th-century scientific community yet having many interests and concerns outside of it. He was a religious man, son of an Episcopalian mother and a Church of Scotland father. Later in life he had an Evangelical conversion.
More difficult for me was Clegg’s somewhat jokey approach – designed, I presume, to lighten the load for non-physicists.
The demon to which the title refers, and which appears from time to time as a device in the text, turns out to be derived from a thought experiment of Maxwell’s which appeared to contradict the second law of thermodynamics (that entropy always increases). Interestingly, the elements of the so-called demonic device are still discussed.
I am left wondering whether this book really works. If I had needed to understand the scientific issues, and, particularly, the famous equations, I would have appreciated a different presentation. If I had wanted a picture of a great mind in action I would have needed less scientific detail. But for other readers the balance may be just right.