MAXWELL’S DEMON: WHY WARMTH DISPERSES AND TIME PASSES
By Hans Christian von Baeyer
Why is it that the cup of hot coffee on your breakfast table doesn’t spontaneously begin to boil over? We all know it won’t, but why not? Heat is one of the basic needs of civilization, a prerequisite for life, but how much do we really know about what heat is and how it operates?
Maxwell’s Demon tells the fascinating story of the scientific “discovery” of heat. Hans Christian von Baeyer, a professor of physics, is one of America’s leading authors of popular science. Engaging without being condescending, he presents the evolution of the laws of thermodynamics in lucid prose, highlighted by parable and historical anecdote.
We need more writers like von Baeyer. Around a hundred years ago the links between science and what most of us understand as reality began to snap. As another popular science writer, Edward O. Wilson, puts it, 20th century science has seen a progressive alienation from reality, leading to a point where its ruling paradigms have “become the ultimate in strangeness to the human mind.”
In contrast, most of the scientific advances of earlier centuries are comprehensible to any reasonably intelligent person. The questions that early scientists set themselves were universal, their methods basic and functional. Many of their experiments can be duplicated today in a suburban basement.
But then the links began to break. Physics was soon describing a world few of us felt connected to, or capable of understanding. Equations involving the speed of light, or Planck’s quantum of action, seemed less in touch with our everyday lives and intuitions than the force of gravity had been. The models and theories were becoming, von Baeyer admits, “a bit difficult to imagine, and highly impractical to check out.”
Thus when Benjamin Thompson discovered the nature of heat in 1797 he did so by noticing the increase in water temperature produced by the friction of boring out a cannon barrel. That much is easy to grasp, and would have been comprehensible to most people at the time. The “Optimal Thermal Ratchet” built by a French physicist in 1995 is another story altogether.
But with von Baeyer as guide, readers need not be afraid. Always stimulating, never intimidating, Maxwell’s Demon is a wonderful introduction to one of the great adventures of the mind.
Review first published August 29, 1998.