Speaker: Kosuke Komeda

Title: Singularities of the dual curve of a certain plane curve in positive characteristics

Abstract:
It is well known that the Gauss map for a complex plane curve is birational, whereas the Gauss map in positive characteristic is not always birational.
Let p be a prime integer, and q a power of p. We study a certain plane curve C of degree q^2 + q + 1 for which the Gauss map is inseparablewith inseparable degree q. As a special case, we will show the relation between the dual curve of the Fermatcurve of degree q^2 + q + 1 and the Ballico-Hefez curve.