"It's a funny old world," by Ian Stewart. New Scientist, 5 February2000, pages 41-43.
This article describes one of the most famous problems in mathematics which hasresisted proof for nearly a century: the three-dimensional Poincare conjecture.Named after the French mathematician Henri Poincare, the conjecture askswhether all three-dimensional shapes having a certain property are basicallythe same as a three-dimensional sphere. Part of what makes this conjecture sotantalizing is that it has been solved in every other dimension except three."It's a sobering thought that while we understand all sorts of astonishingthings about space of thousands of dimensions, we still cannot answer astraightforward question about the 3D space that we live in," Stewart writes.
--- Allyn Jackson