Desmic quartic surfaces in arbitrary characteristic

A desmic quartic surface is a birational model of the Kummer surface of the self-product of an elliptic curve. We recall the classical geometry of these surfaces and study their analogs in arbitrary characteristic. Moreover, we discuss the cubic line complex $\frakG$ associated with the desmic tetrahedra introduced by G. Humbert. We prove that $\frakG$ is a rational $\bbQ$-Fano threefold with 34 nodes and the group of projective automorphisms isomorphic to $(\frakS_4\times \frakS_4)\rtimes 2$.