Modes of the Kerr geometry with purely imaginary frequencies

Understand

In this paper, we examine the behavior of modes of the Kerr geometry when the mode's frequency is purely imaginary.

• We demonstrate that quasinormal modes must be polynomial in nature if their frequency is purely imaginary, and present a method for computing such modes.
• The nature of these modes, however, is not always easy to determine.
• Some of the polynomial modes we compute are quasinormal modes.