Quasi-admissible, raisable nilpotent orbits, and theta representations
摘要
We study the quasi-admissibility and raisability of some nilpotent orbits of a covering group. In particular, we determine the degree of the cover such that a given split nilpotent orbit is quasi-admissible and non-raisable. The speculated wavefront sets of theta representations are also computed explicitly and are shown to be quasi-admissible and non-raisable. Lastly, we determine the leading coefficients in the Harish-Chandra character expansion of the theta representations of covers of the general linear groups.