This Viewpoint relates to an article by J H Hannay (1985 J. Phys. A: Math. Gen. 18 221) and was published as part of a series of Viewpoints celebrating some of the most influential papers published in Journal of Physics A, which is celebrating its 50th anniversary.
This Viewpoint relates to an article by den Nijs (1979 J. Phys. A: Math. Gen. 12 1857) and was published as part of a series of Viewpoints celebrating 50 of the most influential papers published in the J. Phys. series, which is celebrating its 50th anniversary. In this landmark paper Marcel den Nijs, at that time a graduate student supervised by Hubert Knops in Nijmegen, The Netherlands, proposed an exact formula for the thermal critical exponents of the two-dimensional q-state Potts model. The enduring influence of this paper is a measure of the importance of the Potts model and the value of exact results