Topology

  • Links and Knots
    article

    Links and Knots

    Some puzzles requiring no knowledge of knot theory, just a careful inspection of the patterns. A glimpse of the classification of knots, prime knots, crossing numbers and knot arithmetic.
  • Impossible Polyhedra
    article

    Impossible Polyhedra

    Is it possible to make an irregular polyhedron using only polygons of, say, six, seven and eight sides? The answer (rather surprisingly) is 'no', but how do we prove a statement like this?
  • The development of spatial and geometric thinking: 5 to 18
    article

    The Development of Spatial and Geometric Thinking: 5 to 18

    This is the first article in a series which aim to provide some insight into the way spatial thinking develops in children, and draw on a range of reported research. The focus of this article is the work of Piaget and Inhelder.
  • Tangles
    article

    Tangles

    A personal investigation of Conway's Rational Tangles. What were the interesting questions that needed to be asked, and where did they lead?
  • Symmetric Tangles
    article

    Symmetric Tangles

    The tangles created by the twists and turns of the Conway rope trick are surprisingly symmetrical. Here's why!

Displaying 11 - 20 of 22