Mathematical Digest

Short Summaries of Articles about Mathematics
in the Popular Press

"Here be no dragons," by David Ruelle. Nature, 3 May 2001, page 27.

This brief article presents a brief description of the basic ideas of chaostheory in order to pose an intriguing question: "Can one construct aprobabilistic hstory of the world---the formation of the Solar System, life onEarth, or human history?" Chaos theory might be one of the ingredients in sucha history. "To take a concrete example," Ruelle writes, "instead of askingwhen biological evolution decided that terrestrial vertebrates have four limbs,we might ask what the probability was that at some prescribed earlier time, saythe Cambrian, they would develop six limbs."

--- Allyn Jackson