Saturday, April 21, 2018

Two book reviews by Freeman Dyson

A wonderful review The key to everything, a review of

Scale: The Universal Laws of Growth, Innovation, Sustainability, and the Pace of Life in Organisms, Cities, Economies, and Companies

by Geoffrey West
Freeman Dyson not only points out good points of the book as well as what is missing and words of caution towards the end:
The last time humans invented a grand unified theory to make our existence sustainable was when Karl Marx came up with dialectical materialism. The theory had great success in changing human behavior over large areas of our planet. But the changes did not prove to be sustainable, and the theory did not remain unified. It seems likely that West’s theory will run into similar difficulties.
The choice of an imagined future is always a matter of taste. West chooses sustainability as the goal and the Grand Unified Theory as the means to achieve it. My taste is the opposite. I see human freedom as the goal and the creativity of small human societies as the means to achieve it. Freedom is the divine spark that causes human children to rebel against grand unified theories imposed by their parents.”
Along the way, Freeman Dyson points out “West is evidently unaware of Fang and Li’s insight.” 
The insight is explained in an earlier review of Freeman Dyson:
“This gloomy picture of the future was known as the heat death. Learned scientists and scholars portrayed the heat death as our inevitable fate. The paradox appears when we look out at the real universe and see nothing resembling the heat death. Both in the world of astronomy and in the world of biology, we see evolution moving in the opposite direction, from disorder to order, from death to life. Everywhere we see new and intricately ordered structures arising out of primeval chaos. The most obvious and familiar example of order growing out of chaos is the emergence of our ordered system of sun and planets out of a featureless cloud of interstellar dust and gas.
Fang’s chapter “How Order Was Born of Chaos” is a beautiful piece of scientific explanation. He explains the paradox of order and disorder as a consequence of the peculiar behavior of gravity. Unlike other kinds of energy, gravitational energy is predominantly negative. Our gravitational energy becomes more and more negative as we walk downhill toward the center of the earth. In any situation where gravitational energy is dominant, temperature and energy flow in opposite directions. The flow of heat works against the heat death, making warm objects hotter and cool objects colder. Instead of disappearing, temperature differences grow as time goes on. In the universe as a whole, gravitational energy is always dominant, and so the heat death never happens. Order grows out of chaos because we live in a universe with structures dominated by gravity. The dismal images of doom and gloom associated with the heat death turn out to be illusory. Fang’s understanding of the paradox brings us into a hopeful universe, with beauty and diversity growing around us as we move into the future.”
This passage from his review of the autobiography of Fang Lizhi The heritage of a great man.

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