On the Chirality of Torus Curves and Knots

As is well known, a (p, q) torus knot is topologically equivalent to a (q, p) torus knot. The sign of the writhe number, which characterizes the topological chirality, must evidently be the same in both cases. We here show by an analytic criterion related to the torsion that a (p, q) torus curve and a (q, p) torus curve have opposite chirality, although they are not enantiomers. An erratum to this article can be found at