17 November 08

August Ferdinand Möbius (November 17, 1790 - September 26, 1868) was a German mathematician who discovered the unusual properties of the "Möbius strip" in 1858. You make one by looping a long strip of paper, twisting the paper once before fastening it (e.g., with tape) to complete the loop. The surface of this object now has only one "side," as you can prove by drawing a continuous pencil line along the path. The technical definition is "a non-orientable two-dimensional surface with only one side when embedded in three-dimensional Euclidean space" (Wikipedia, article on Möbius). Many of M. C. Escher's drawings are based on Möbius patterns. My tie represents a crude attempt to wear a one-sided loop to celebrate Möbius' birthday.