# Gustav Nilsson: Mode Stability for Gravitational Instantons of Type D

**Time: **
Thu 2023-09-28 10.15 - 11.15

**Location: **
3418, Lindstedtsvägen 25

**Language: **
English

**Participating: **
Gustav Nilsson, AEI

We study Ricci-flat perturbations of gravitational instantons of Petrov type D. Analogously to the Lorentzian case, the Weyl curvature scalars of extreme spin-weight satisfy a Riemannian version of the separable Teukolsky equation. As a step towards rigidity of the type D Kerr and Taub-bolt families of instantons, we prove mode stability, i.e. that the Teukolsky equation admits no solutions compatible with regularity and asymptotic (local) flatness.