Elliptic curvature estimates for linearised gravitational perturbations of Kerr in the full sub-extremal range $|a|<M$

Abstract

We consider the linearised vacuum Einstein equations around a Kerr exterior solution and present a scheme to prove elliptic $L^2(\mathbb{S}^2)$-estimates for the linearised curvature quantities in the equations. The scheme employs the linearised system of equations derived in the first author's doctoral thesis and applies to the full sub-extremal range of Kerr parameters $0\leq |a|<M$.