Tools: Entropy

Entropy

4 March 2024

Dear Jo,

Thanks again for being the willing recipient of my musings.

The Second Law of Thermodynamics contrasts order (structure, non-randomness) with uniformity (no structure). Sure it’s hard to grasp – failing Thermo was what led me to switch from Mechanical to Electrical Engineering in 1967!

Interpretation: Any ordered thing (a tree, a human, a house, a system of government, an economy) tends to lose structure over time, unless energy is introduced to sustain its form.

Given enough time (without getting more energy), the structure will disintegrate into a uniform “soup” of its basic components.

In an amazing instance of cross-discipline insight, the physicist Erwin Schroedinger, without any training in biology, wrote a little book in 1944 entitled “What is Life?” [1] He was fascinated by the ability of living cells to thrive and propagate. How could the orderliness of life perpetuate itself in the face of Entropy? [2]

(Entropy is a measure of how uniform the “soup” has become).

Watson and Crick credited Schroedinger with the insights that led them to discover DNA, as they published their research in 1953.

Uniform “soup” is an end state. Nothing can be done with it - it contains no potential energy.

Energy requires a differential of whatever kind to do work. To provide anything structured with the ability to grow more complex, or even, simply to sustain itself. Think of entropy as the lack of potential.

“Potential” is the opportunity to extract work from a system. Think of a battery – voltage measures electrical potential. If the battery is fully discharged, it has maximum entropy. Useless, in other words.

Differences in potential are essential to the working of systems. In economics – if all have equal assets, the market falls apart. In sports, if all teams have equal skills, there is no winner (or loser, either). In politics - if both parties have equal strength, nothing can move forward; the system falls apart.

Entropy and it’s opposite (potential) are useful concepts to understand any system...

One last thing. Do not take Thermo in college...

Grampa Jeff

1. Schroedinger, Erwin, “What is Life? The Physical Aspect of the Living Cell.” (Countless editions)

2. Ball, Philip, “How Life Works: A User’s Guide to the New Biology,” University of Chicago Press, Chicago, 2023. Chapter 8, entire.