Tag Archives: laws of thermodynamics

Are these the laws of engineering?

While shopping on-line for books during a pandemic lockdown allows you to buy new books, I found it difficult browse online and find new authors. Perhaps because the algorithms employed by the booksellers are too busy guessing my interests or promoting the latest book that they want me to buy. So it was a pleasure to be able to walk into a bookshop again in a couple of months ago. One of the new authors that I discovered was Niall Williams. I have just finished reading his 2019 novel ‘This is happiness‘ which weaves together the life of an Irish village in which nothing ever changes until the coming of electricity, a tale of coming of age and another of burying the past. In the middle of this beautifully-told story, a salesman is extolling the virtues of the electrical gadgets that they can install in their new electrified homes and says that ‘the first law of engineering was to make the world a better place’. The narrator quietly tells us the second law, which the salesman doesn’t state, ‘that without exception everything that was engineered would one day break down … usually one day after each machine had become indispensable to living’. This is a consequence of the second law of thermodynamics, which is that entropy, or disorder, increases in all real processes. Hence, the localised order, which we create when something is engineered, is constantly being eroded until eventually the disorder leads to a break down. Or, as Murphy’s law states ‘Anything that can go wrong will go wrong’. However, the definition of the first law of engineering was the one that caught my eye and resonated with a corny introduction that I used in a talk on why we need to change the way we teach engineering. I played a recording of Louis Armstrong singing ‘What a wonderful world‘ and then talked about the wonderful world that engineers have created before highlighting the unsustainable environmental costs of our ‘wonderful’ engineered world and that it is inaccessible to a large portion of the world’s population. I gave that talk many times to groups of engineering professors in the USA between about 2006 and 2012; maybe I had some impact but there is still a lot of changes needed to achieve a sustainable society. So, the first law of engineering should be to make the world a better place for everyone.

Reference:

Niall Williams, This is happiness, London: Bloomsbury Publishing, 2019

Everything is flux but it’s not always been recognised

Decorative photograph or ruins of Fountains Abbey next to River SkellI am teaching thermodynamics to first year undergraduate students at the moment and in most previous years this experience has stimulated me to blog about thermodynamics [for example: ‘Isolated systems in nature?’ on February 12th, 2020].  However, this year I am more than half-way through the module and this is the first post on the topic.  Perhaps that is an impact of teaching on-line via live broadcasts rather than the performance involved in lecturing to hundreds of students in a lecture theatre.  Last week I introduced the second law of thermodynamics and explained its origins in efforts to improve the efficiency of steam engines by 19th century engineers and physicists, including Rudolf Clausius (1822 – 1888), William Thomson (1827 – 1907) and Ludwig Boltzmann (1844 – 1906).  The second law of thermodynamics states that the entropy of the universe increases during all real processes, where entropy can be described as the degree of disorder. The traditional narrative is that thermodynamics was developed by the Victorians; however, I think that the ancient Greeks had a pretty good understanding of it without calling it thermodynamics.  Heraclitus (c. 535 BCE – c. 475 BCE) understood that everything is in flux and nothing is at rest so that the world is one colossal process.  This concept comes close to the modern interpretation of the second of law of thermodynamics in which the entropy in the universe is constantly increasing leading to continuous change.  Heraclitus just did not state the direction of flux.  Unfortunately, Plato (c. 429 BCE – c. 347 BCE) did not agree with Heraclitus, but thought that some divine intervention had imposed order on pre-existing chaos to create an ordered universe, which precludes a constant flux and probably set back Western thought for a couple of millennia.  However, it seems likely that in the 17th century, Newton (1643 – 1727) and Leibniz (1646 – 1716), when they independently invented calculus, had more than an inkling about everything being in flux.  In the 18th century, the pioneering geologist James Hutton (1726 – 1797), while examining the tilted layers of the cliff at Siccar Point in Berwickshire, realised that the Earth was not simply created but instead is in a state of constant flux.  His ideas were spurned at the time and he was accused of atheism.  Boltzmann also had to vigorously defend his ideas to such an extent that his mental health deteriorated and he committed suicide while on vacation with his wife and daughter.  Today, it is widely accepted that the second law of thermodynamics governs all natural and synthetic processes, and many people have heard of entropy [see ‘Entropy on the brain’ on November 29th, 2017] but far fewer understand it [see ‘Two cultures’ on March 5th, 2013].  It is perhaps still controversial to talk about the theoretical long-term consequence of the second law, which is cosmic heat death corresponding to an equilibrium state of maximum entropy and uniform temperature across the universe such that nothing happens and life cannot exist [see ‘Will it all be over soon?’ on November 2nd, 2016].  This concept caused problems to 19th century thinkers, particular James Clerk Maxwell (1831 – 1979), and even perhaps to Plato who theorised two worlds in his theory of forms, one unchanging and the other in constant change, maybe in an effort to dodge the potential implications of degeneration of the universe into chaos.

Image: decaying ruins of Fountains Abbey beside the River Skell.  Heraclitus is reported to have said ‘no man ever steps twice into the same river; for it’s not the same river and he’s not the same man’.