Journées Arithmétiques XXXI, İstanbul, Turkey, 1 - 05 July 2019, pp.33
Hurwitz class numbers occur in various places in the theory of classical modular and Jacobi forms.
Recently, in joint work with N-P Skoruppa, we found an extension of this theory to (totally real)
number fields. In this talk we explain the context for these considerations, introduce the pendants
of Hurwitz class numbers in totally real number fields and the appearance of these new numbers in
the theory of Jacobi forms over number fields.