Fun with physics
EVERY week I receive one or two e-mails asking if I can recommend a book on quantum physics or relativity. Despite the huge number of books on these subjects, it seems that readers are still hungry for something intelligent, fun, readable and slimmer than “War and Peace.†Marcus Chown’s “The Quantum Zoo†fits the bill.
Chown immediately captures the reader’s attention with a series of staggering factoids. For example, you age faster at the top of a building than at the bottom. Also, 1% of the static on a television tuned between channels is radiation left over from the Big Bang. Equally bizarre is the statement that every breath you take contains an atom exhaled by Marilyn Monroe. Chown reminds us too that the Norwegian novelist Jostein Gaarder once wrote: “A hydrogen atom in a cell at the end of my nose was once part of an elephant’s trunk.â€
Such facts are amazing, but Chown invests them with mind-blowing power by examining the physics behind them. When we’re young, we’re told that atoms are like mini solar systems, with tiny planet-like electrons orbiting a massive central nucleus. As in the solar system, there are vast empty spaces between the orbiting particles, so what would happen if atoms were squished to get rid of these gaps? According to another of Chown’s factoids, compacting atoms would result in squeezing the entire human race into the volume of a sugar cube.
And this is more than a mere mind game, because such a super-squeezed state of matter really does exist; it is created when a star dies in a supernova explosion. The resulting neutron star often has a distinctive signature because it usually spins at high speed and emits a beam of radio waves, appearing to us rather like a lighthouse flashing in the emptiness of space. This pulsing explains why spinning neutron stars are better known as pulsars. They were first spotted in 1967, by British radio astronomer Jocelyn Bell Burnell, who briefly wondered whether the regular pulsing was the result of an intelligent agent and thus named them LGM (for Little Green Men).
Much of the material in “The Quantum Zoo†has been covered by other authors, but Chown gives it all a lively twist and throws in a few extra nuances when he recounts the familiar anecdotes. For example, Robert Atkinson and Fritz Houtermans were the first to work out the nuclear reactions fueling the stars -- reactions that made sense only in the context of quantum physics. They published their ideas in 1929, in the journal Zeitschrift fur Physik. Chown repeats Houtermans’ story about an event that took place the night after they completed their research paper on stellar fusion: “That evening, after we had finished our essay, I went for a walk with a pretty girl. As soon as it grew dark the stars came out, one after another, in all their splendor. ‘Don’t they shine beautifully?’ cried my companion. But I simply stuck out my chest and said proudly: ‘I’ve known since yesterday why it is that they shine.’ †Charlotte Riefenstahl was clearly impressed; she later married him. Chown points out something I had not previously been aware of, which is that he married her twice (“but that’s another storyâ€).
“The Quantum Zoo†has its fair share of humor. When Chown discusses the nature of light, he points out that it sometimes appears to be a wave and sometimes behaves like a particle. So which is it, a wave or a particle? In fact, light is both a wave and a particle (what might be called a wavicle), which is why in 1921 English physicist William Bragg remarked: “On Mondays, Wednesdays and Fridays, we teach the wave theory and on Tuesdays, Thursdays and Saturdays the particle theory.†Similarly, electrons are not just particles but also possess wavelike properties -- enabling J.J. Thomson to win the Nobel Prize in 1906 for showing that electrons are particles and his son G.P. Thomson to win the Nobel Prize in 1937 for showing that electrons are waves.
Chown’s brief primer on quantum physics and relativity introduces the reader to a series of weird and wonderful physics: time travel, multiple realities, multiverses, superfluids. Best of all, it is all good physics as told by a good physicist. As such, the book is an effective antidote to some of the baloney that now and then creeps into popular introductions to quantum physics.
The worst example of this may well be “What the Bleep Do We Know!?†-- a horrendous 2004 documentary purporting to explain quantum physics to the general public. Though it was praised by some critics and became the third-highest-grossing documentary of all time, the film took a few ideas in quantum physics and bent and distorted them so extravagantly that viewers were misled into thinking all sorts of peculiar things. According to “What the Bleep
