|Weyl laws in the theory of automorphic representations are asymptotic laws, which address the question whether and how many automorphic representations exist with principal series representations at the archimedean places. These do (except for finitely many) not correspond to Galois representations and cannot be understood by algebra-geometric methods.
Generalizations of these Weyl laws to the hybrid case, where not at all factors at the archimedean places are principal series representations, are presented. Moreover, these Weyl laws will be uniform in the level aspect, i.e., include and refine even the classical Weyl laws for Maass wave forms in the aspect that the dependency of the error term from the surface is explicit.
The key difficulty in the proof of these laws involves defining a suitable partition of the cuspidal automorphic spectrum and a specialization of the Arthur trace formula for GL(2) according to a specific partition. The presented formulas generalize simultaneously the original Selberg trace formula for the Laplace eigenvalues and Eichler-Selberg trace formulas for Hecke eigenvalues, yet avoid computational difficulties from the classical theory such as the computation of the scattering matrices. In this context, my formulas are given for an arbitrary global fields.
Reference: My PhD thesis, arXiv:1212.4282