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There Ain’t ‘Alf Some Clever Bastards – Part Seventy Four

Ludwig Boltzmann (1844 – 1906)

Science in general and physics in particular, whilst fascinating, has always been a closed book to me. Thank goodness there have been cleverer people than I who have made a significant contribution to the understanding of how the universe works like the latest inductee into our illustrious Hall of Fame, Austrian born Ludwig Boltzmann.

Take entropy or the degree of disorder and uncertainty in a system. I have always thought that tidying up was a bit of a waste of time and now I have the scientific evidence to back up my empirical observation. If I’m prevailed upon to tidy up a pile of clothing, have I contributed to a decrease in disorder and a corresponding reduction in entropy? Not a bit of it. You see, there are side effects to my attempt to restore order to my unruly pile of glad rags. I will be breathing, probably cursing, metabolising and warming my surroundings. When everything is totted up, the total disorder measured by entropy will have increased.

Boltzmann’s contribution to the corpus of scientific knowledge was to apply statistical techniques to understanding the second law of thermodynamics, first articulated by the French scientist Sadi Carnot in 1824, that stated that the total entropy of an isolated system can only increase over time. He was an atomist and believed that these tricky little devils held the key to the understanding of entropy. By blending the laws of mechanics as applied to the motion of atoms with probability theory, he concluded that the second law of thermodynamics was essentially a statistical law. The formula he derived to describe entropy in 1877 was S = k · log W. Clear as mud to me but it became the foundation of statistical mechanics.

Our hero didn’t finish there. Between 1880 and 1883 he continued to develop his statistical approach to explaining the mysteries of the universe and refined a theory to explain friction and diffusion in gases. In the late 1880s, following Hertz’s discovery of electromagnetic waves, Boltzmann devised a number of experiments to demonstrate radio waves, lecturing on the subject.

Impressive as this all is, Boltzmann did not find favour with his colleagues. Atomism, which is the bedrock of modern-day physics was under attack at the time and Boltzmann’s theory that entropy was irreversible was counter to prevailing thought at the time. After all, the equations of Newtonian mechanics are reversible over time and the great Poincare had demonstrated that a mechanical system in a given state will always return to the state over time.

One of Boltzmann’s leading critics was Wilhelm Ostwald who paid no heed to atoms, preferring to explain physical science purely in terms of energy conditions. Ostwald put the energist case against Boltzmann succinctly, “The actual irreversibility of natural phenomena thus proves the existence of processes that cannot be described by mechanical equations, and with this the verdict on scientific materialism is settled.” Scientific discussions at the time were lively affairs, one contemporary describing a debate between Boltzmann and Ostwald as resembling “the battle of the bull with a supple fighter”.

The constant criticism of his theories and the need to defend himself vigorously against all-comers wore Boltzmann down. Whilst on holiday with his wife and daughter at the Bay of Duino near Trieste in 1906, he committed suicide by hanging himself. Ironically, shortly after his death discoveries in atomic physics such as the Brownian motion – the random movement of particles in a liquid or gas which can only be explained by statistical mechanics – reinforced the primacy of atomic theory and established Boltzmann’s work as the cornerstone of modern-day physics.

For this, Ludwig, you are a worthy inductee into our Hall of Fame.

If you enjoyed this, why not try Fifty Clever Bastards by Martin Fone which is now available on Amazon in Kindle format and paperback. For details follow the link https://www.amazon.co.uk/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=fifty+clever+bastards