# Item

ITEM ACTIONSEXPORT

Released

Journal Article

#### Second order gauge invariant gravitational perturbations of a Kerr black hole.

##### MPS-Authors

##### External Resource

No external resources are shared

##### Fulltext (restricted access)

There are currently no full texts shared for your IP range.

##### Fulltext (public)

9811019v2.pdf

(Preprint), 287KB

Phy.Rev.D.59.124022.pdf

(Publisher version), 296KB

##### Supplementary Material (public)

There is no public supplementary material available

##### Citation

Campanelli, M., & Lousto, C. O. (1999). Second order gauge invariant gravitational
perturbations of a Kerr black hole.* Physical Review D,* *59*(12):
124022. doi:10.1103/PhysRevD.59.124022.

Cite as: https://hdl.handle.net/11858/00-001M-0000-0013-5834-7

##### Abstract

We investigate higher than the first order gravitational perturbations in the Newman-Penrose formalism. Equations for the Weyl scalar $\psi_4,$ representing outgoing gravitational radiation, can be uncoupled into a single wave equation to any perturbative order. For second order perturbations about a Kerr black hole, we prove the existence of a first and second order gauge (coordinates) and tetrad invariant waveform, $\psi_I$, by explicit construction. This waveform is formed by the second order piece of $\psi_4$ plus a term, quadratic in first order perturbations, chosen to make $\psi_I$ totally invariant and to have the appropriate behavior in an asymptotically flat gauge. $\psi_I$ fulfills a single wave equation of the form ${\cal T}\psi_I=S,$ where ${\cal T}$ is the same wave operator as for first order perturbations and $S$ is a source term build up out of (known to this level) first order perturbations. We discuss the issues of imposition of initial data to this equation, computation of the energy and momentum radiated and wave extraction for direct comparison with full numerical approaches to solve Einstein equations.