THE NOTHING THAT IS:
A Natural History of Zero
By Robert Kaplan
Oxford University Press
225 pages, $22
ABSOLUTE ZERO AND THE CONQUEST OF COLD
By Tom Shachtman
261 pages, $25
Now that 2000 has rung itself in without bringing the world to an end, it may be time to think about that one little digit that had us all so worked up for a while: the humble zero. In recent books, two chroniclers of science take on the mathematical and cryogenic history of zero, with sometimes entertaining results.
Robert Kaplan's "The Nothing That Is" notes that zero is a human invention that lagged far behind 1, 2, 3 and the rest. The ancient Sumerians had a concept of zero as a place marker, registering its existence with stone wedges pushed into wet clay tablets. The Mayans, who flourished from 300 B.C. to 900 A.D., had a symbol for zero: a tattooed man in a necklace with his head thrown back. Eventually zero became a marker of power -- you can't be a millionaire without six of them -- and part of the yin and yang of computer language, where 1 and 0 chatter back and forth endlessly to call into being everything from your telephone bill to the flight of the space shuttle.
Along the way, Kaplan writes, zero has engendered much fear and loathing. It has been perceived as the figure of death, for what is life but a something, the opposite of nothing? The author notes that for much of history humankind has viewed itself as the battleground of God vs. the devil, and that the void was identified with evil; and thinkers have long suspected that giving a name to forces and beings could call them into existence. If God's best feat was creating the universe out of nothingness, then man could hardly be expected to warm up to zero, the symbol of all that God isn't.
Kaplan, a mathematics professor at Harvard, writes with enthusiasm and a wry wit, and his passion for math is evident. ("Its muse speaks only to those who ardently pursue her," he says. "And what is that pursuit? A mixture of tinkering and inspiration . . . an ongoing conversation between guessing and justifying, between imagination and logic.") Be forewarned, though, that you won't be reading "The Nothing That Is" at 60 pages an hour. It's salted with equations and formulas, symbols from ages past, and such keep-you-awake topics as: Just why can't we divide by zero, anyway?
Tom Shachtman has more to work with in "Absolute Zero and the Conquest of Cold," his tale of scientists toiling in the lower reaches of temperature. It was only in 1877 that the French scientist Louis-Paul Cailletet liquefied oxygen and nitrogen, making the first major stride toward minus 273.15 degrees Celsius. That's the chilly point at which all molecular motion ceases, and we haven't gotten there yet. The closest, Shachtman reports, came in February 1999: 50 billionths of a degree above that point -- colder than outer space, so cold that light itself travels only 38 mph.
Shachtman has some fun with the peccadilloes and peculiarities of the scientists chasing the nether reaches of the thermometer. We see the Dutch researcher Heike Kamerlingh Onnes, for example, on the fateful July day in 1908 when he managed to liquefy helium, so engrossed in his work that his wife had to feed him his lunchtime sandwich bit by bit while he turned dials and watched gauges.
Why chase after that frigid stillness in the first place? Mostly because pure scientists yearn to know the extremes of matter. It's in extremis that matter yields its secrets. But there are practical benefits as well, from your refrigerator and air conditioner (commercial offshoots of cooling mechanisms developed in the laboratory) to the almost limitless promise of superconductive wiring that would pretty much ensure plenty of cheap energy worldwide.
Baby, it's cold outside -- be glad we won't be getting much closer to absolute zero.