OVERVIEW

Another of the major scientific shifts that occurred in the nineteenth century was the primary role that thermodynamics came to play in explaining the nature of change in the physical world -- observations that were almost immediately carried over into the human world as well. A 20th century physicist remarked that the laws of thermodynamics seem different from other laws in physics and that is because they "smell of their human origins." We'll take this observation as a way to examine the multidimensionality of a set of laws that are not neat descriptive equations, but rather verbal expressions of limits that are placed on human beings (such as the inability to construct a perpetual motion machine). Beyond this thermodynamics is a set of phenomena-- heat, temperature, energy -- which are widely applicable to our everyday lives in ways, that say, gravity is not (gravity is constantly in operation and our world is subject to its effects, but it is not something which is called to our attention in the way that thermodynamic effects are -- perhaps because they are constantly marking conditions of change). Another aspect that is central to this idea of the laws being intermeshed with the world of humans rather than of objects is in how attention to processes of heat and the work that could be produced by means of heat derived from such tangible activities as the generation of heat in the boring of cannons. The problems of steam engines -- which, while capable of immense power managed to be incredibly wasteful in terms of the energy needed to be put into the system -- such as coal in a locomotive, in which the consumption of the source came nowhere equal in output to the input. The human body also came to be treated as a heat engine, mingling these laws simultaneously with physical and biological conditions. And, finally, the earth itself could be treated as a heated body that was cooling over time with a rate that could be calculated, providing an age for the Earth -- one that Lord Kelvin determined to be too short for Darwin's theory of evolution to operate, which presented a grave obstacle to the theory.

LIST OF READINGS AND LEARNING ACTIVITIES

Reading Assignments:

Ede & Cormack, Chapters 7 and 8

Learning Activities:

Watch these videos:
- Thermodynamics": Crash Course History of Science #26 (13 min)
- Sean Caroll, Minute Physics: "Why Doesn't Time Flow Backwards?" (4 min.) and "How Entropy Powers the Earth" (4 min.)
- "James Clerk Maxwell: A Sense of Wonder" / James Clerk Maxwell Foundation (28 min.)
Listen to this BBC Podcast: In Our Time: "Heat"
Read this website:
- Philip England, Peter Molnar, and Frank Richte, "Kelvin, Perry and the Age of the Earth," American Scientist (July- August 2007)