The word comes from the Greek topos for "place," and was introduced into English by Solomon Lefschetz in the late 1920s.
A topologist has been described as someone who doesn't know the difference between a doughnut and a coffee cup. Substitute "care about" for "know" and this becomes more accurate.
Imagine a doughnut-shape, or torus, made of soft clay. A potter can easily shape this into a cup with a handle without removing or creating any new holes. Both shapes, in topology, are said to be genus 1 – objects with a single hole. A sphere, by contrast, is genus 0 (no holes), while an eyeglass frame, with the lenses removed, is genus 2.
For more on topologically intriguing structures, see Möbius band and Klein bottle.
Related entry algebraic topology
Related categories TOPOLOGY
• SPACE AND TIME
Home • About • Copyright © The Worlds of David Darling • Encyclopedia of Alternative Energy • Contact