The Origin of Asymmetry
What brings order to the structure of the universe?
[T]his theory emphasizes that the asymmetry of today is a result of the breaking of symmetry, and this reminds us of a truth in aesthetics:
symmetry + defect = beauty
Indeed, one can find many instances illustrating this truth in the arts: gardens in studied randomness, Venus with arms broken off, the Qin funeral warriors and horses in strict, symmetrical formation but all with different expressions. Why does symmetry plus "defect" equal beauty?
— Fang Lizhi and Li Shu Xian, The Creation of the Universe
Lizhi and Xian are writing in 1989 about how the Higgs Theory may account for the baryon asymmetry in our universe. Some physicists working with LHC data appear to have verified at least some of the theory. To see a theory so fundamental verified after so many years of effort is a beautiful thing in itself, but there are many other beautiful things to be found in this book:
- Why is the night dark? Because the universe is expanding — the futher away you look, the faster the expansion away from us. (Chapter 2) The proportionality constant between distance and velocity is Hubble's Constant.
- How old is the universe? About 20 billion years. You get this estimate by taking the expansion observed above and running it in reverse. (Chapter 3) Perhaps that was too easy, because they throw in the same chapter estimates for the age of the earth based on isotopic abundance (4.5 billion years), and an explanation of how the periodic table was populated by nuclear fusion in the stars.
- Is the universe infinite? Maybe. It depends on whether we're above a critical density that is hard to measure. If most of the universe's mass is in luminous galaxies, then yes. But 90% is non-luminous "dark matter," so maybe not. (Chapters 4 and 5)
- What brings order to the structure of the universe? Gravity. Gravitational systems both heat up and lose entropy as they collapse. This is a mind bender for anybody used to terrestrial thermodynamics — heating things up almost always means higher entropy here on earth! (Chapter 6)
After a long hiatus the Broken Symmetry blog is back. As a first post, it seemed appropriate to review and recommend this amazing text by Lizhi and Xian, and especially their explanation of the relationship between order and gravity.
Each of us is faced with a fundamental problem of resolving the tension between our desire to be special and our desire to belong. While the creators, the heros, the pioneers, the founders are held up as icons in Silicon Valley, I find it helpful to be reminded that it's the gravitational attraction of social life that brings order to the chaos of creation. The Broken Symmetry blog is back to reestablish old connections and hopefully make some new.
It is worthy of note that the first author of this text, Fang Lizhi, who sadly passed away in 2012, was expelled from the Communist Party of China in 1987 for his part in the pro-democracy movement in China that culminated in the Tiananmen Square protests of 1989 — the same year this book appeared in print in the United States.
The book was cited in Freeman Dyson's review of James Gleick's The Information. But I see that Dyson cited it also here. And since I'm linking book reviews by Freeman Dyson, don't miss this one of West's Scale or this one about interplanetary colonization.