  In this article, the superradiation stability of Kerr-Newman black holes is
discussed by introducing the condition used in Kerr black holes y into them.
Moreover, the motion equation of the minimal coupled scalar perturbation in a
Kerr-Newman black hole is divided into angular and radial parts. We adopt the
findings made by Erhart et al. on uncertainty principle in 2012, and discuss
the bounds on y. The extreme value of the narrow uncertainty principle can be
smaller experimentally, and the extreme value of the broad uncertainty
principle can also be smaller as can be seen from its expression. We know that
the uncertainty principle reflects the probability current density, and its
extremum reflects the particular case of the probability current density
equation. As seen above, the bound from y in this article makes sense. This is
about the introduction of new parameters in superradiation of black holes.
