Establish compatibility of positive- and negative-spin systems with one physical perturbation
Establish whether the separated radiative systems for positive and negative spin weights are compatible representations of a single physical linearized Einstein–Maxwell perturbation, and determine the conditions required for their compatibility.
References
We also leave open compatibility of the systems for positive and negative spin weights for one physical perturbation, and full Einstein--Maxwell reconstruction.
— Separation of variables for coupled radiative perturbations of Kerr-Newman-de Sitter black holes
(2610.20500 - Yoshida, 14 Oct 2026) in Section 6, Summary and discussion