I have a habit of wandering around public libraries until a book catches my eye. I do this frequently enough that if you were to plot the book titles I happen upon against my enjoyment of them, you’d be looking at perfectly smooth bell curve. In other words: there have been lots of books, and most of them have been neutral. Once in a while though, I’ll find an outlier—a beautiful, beautiful outlier.

Such is the case with David Lindley’s 2001 popular science book, Bolztmann’s Atom: The Great Debate That Launched a Revolution in Physics. Lindley, himself a physicist by training, paints a vivid and sometimes tragic portrait of the legendary founder of statistical mechanics, Ludwig Boltzmann, against the backdrop of 19^th century Vienna. In addition to guiding the reader through the often perilous catacombs of thermodynamic terminology, Lindley illuminates the interplay between philosophy and science and outlines how mental illness (in particular bipolar disorder) was treated in the 1800’s. The book features several titans of science—including James Clerk Maxwell, Josiah Willard Gibbs and Wilhelm Ostwald—as well as important philosopher-scientists, such as Ernst Mach and Hermann von Helmholtz.

Ludwig Boltzmann and co-workers in Graz, 1887. (standing, from the left) Nernst, Streintz, Arrhenius, Hiecke, (sitting, from the left) Aulinger, Ettingshausen, Boltzmann, Klemenčič, Hausmanninger

The main theme of the book is Bolztmann’s life-long struggle to convince the scientific community that atoms really do exist and that, contingently, his theorems really do have physical significance—two tasks which he ultimately failed to complete in his life-time.

Atomic Theory’s Difficult Youth

How do we know that atoms exist? Philosophically, one might expect that matter must be made out of some fundamental, immutable something. Take a piece of chalk and cut it in half. Then take one of those halves and halve it again. Repeat this process until you can divide no further. That indivisible substance is an atom. And indeed, the word atom comes from the Greek atomos, which literally means “uncuttable”.  Thus, Lindley tells us, atomic theory was born not of modern science, but of ancient Greek philosophy.

Democritus, 460 – 370 BC. A Pre-socratic philosopher remembered for his atomic theory of the universe and intense rivalry with Plato, who is said to have disliked him so much that he wished all his books burned.

All this philosophizing is nice, but how we actually know that atoms exist? Remarkably, the first person to “prove” the existence of atoms was none other than a young Albert Einstein, in 1905. Why is this remarkable? Because kinetic theory, which describes gases as being made up of incomprehensibly large numbers of atoms moving randomly and constantly, was propounded by Daniel Bernoulli in 1738, nearly 170 years prior. Moreover, statistical mechanics, the application of probability theory to physical systems with uncertain states (such as a container filled with 10ˆ23 atoms flying around haphazardly), was largely developed by Maxwell, Gibbs, and Boltzmann in the mid 1800’s.

For nearly a hundred years, atomic theory had to waddle through thick molasses just to survive. Statistical mechanics in particular was met with resistance from other scientists, most notably Ernst Mach, who accused it of being unscientific. Mach, an ardent logical positivist, believed that physics should be based strictly off of observable phenomenon and that since atoms are not directly observable, statistical mechanics could never be a valid physical theory. In the case of thermodynamics, Mach thought that a thermodynamic system could and should only be described by the variables we can literally sense, such as pressure and heat flow and volume. Any mention of un-sensible entities was insensible to Mach, and how can we blame him? He was just being a good scientist: allowing his mind to be led only by carefully gleaned evidence—of which Bolztmann’s theories had none.

Mach and Bolztmann participated in public debates which often drew massive lay-crowds. Eventually these debates consumed nearly all of Bolztmann’s time and mental effort and, Lindley believes, knocked him off what little balance he had to begin with. This proverbial straying-from-the-righteous -path was surely made worse by Bolztmann’s genuine neurological illness—an illness that 19^th century doctors were not at all equipped to handle.

Battling Bipolar Disorder

Throughout his life, Ludwig Boltzmann suffered from cyclical mood swings. He would vacillate between hyper-elation and severe depression—an almost sure sign of undiagnosed bipolar disorder. The study of mental illnesses was still in its toddler years during Bolztmann’s time, and so he was diagnosed with something called neurasthenia, a popular umbrella term which encompassed a near infinite set of symptoms such as dizziness, depression, fatigue, fainting and anxiety. The famous author Marcel Proust was also said to suffer from neurasthenia. His advice for coping with it, Lindley paraphrases, was to lie in bed for a week or two and not read the newspaper. Not terrible advice, but it gives you some sense of where psychiatry stood in that time.

Bolztmann’s mood swings were exacerbated by his constantly having to defend atomic theory against naysayers like Mach. On this fragile topic Lindley’s talent really shows. He makes you empathize with Boltzmann’s passion while at the same time respecting Mach’s positivist angle. Through this dichotomy the reader gets a rare insight into how science can often be at the cusp of revolutions: unremittingly brutal. The burden eventually proved too much for Bolztmann and on September 5, 1906 he committed suicide, believing himself to be a scientific failure. We know now that Bolztmann was one of the most brilliant physicists of the last two centuries; his work is taught to trembling undergraduate physics and chemistry students all around the world.

Conclusion

Lindley doesn’t shy away from making the obvious comparison between the state of string theory today and the state of atomic theory in Bolztmann’s time. But he also encourages the reader to be skeptical, and withhold full judgment until data has been gathered—good advice for sure. All in all, Bolztmann’s Atom is an engrossing read for anyone interesting in the history of science and biographies of important scientists. Furthermore, no advanced knowledge of physics or mathematics is needed to read the book, yet another testament to Lindley’s great accomplishment.

Leo Kozachkov (Staff Writer, Rutgers University)
Leo Kozachkov is an undergraduate at Rutgers University, studying physics and mathematics. He is currently working as an Aresty Research Assistant under Professor Thomas V. Papathomas. He enjoys writing, drawing, creating/playing music, going on long walks with his beloved dog, and reading/hoarding books. His grandest hopes are to discover a new physical law, have a mathematical theorem feature his last name, and to write many books.