Generalized orthotoric Kahler surfaces
arXiv:2111.06607 · doi:10.4064/ap211112-19-3
Abstract
In this paper we describe QCH Kähler surfaces of generalized orthotoric type. We introduce a distinguished orthonormal frame on and give the structure equations for . In the case when is conformally Kähler and is not hyperkähler we integrate these structure equations and rediscover the orthotoric Kähler surfaces. We also investigate the hyperkäler case. We prove in a simple way that if is a hyperkähler surface with a degenerate Weyl tensor (i.e. QCH hyperkähler surface) then among all hyperkäler structures on there exists a Kähler structure such that is of Calabi type or of orthotoric type.