Etymologically, geometry is associated with measurement. But is the study of the objects around us really limited to a metric approach?
Does an elastic object not also retain certain properties when it is deformed? Mathematicians have answered all these questions by developing one of the richest branches of mathematics: topology.
Mathematical games with modelling clay ---------------------------
Who did not play with modelling clay as a child? Is it not fun to transform a terrifying dinosaur into an innocent little rabbit? Mathematicians enjoy playing too, though they like to add a few constraints.
This raises the following question: given two modelling-clay sculptures, is it possible to transform one continuously into the other?