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Multipole moments as a tool to infer from gravitational waves the geometry around an axisymmetric body

Thomas P. Sotiriou·Theocharis A. Apostolatos
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Abstract

A binary system, composed of a compact object orbiting around a massive central body, will emit gravitational waves which will depend on the central body's spacetime geometry. We expect that the gravitational wave observables will somehow ``encode'' the information about the spacetime structure. On the other hand, it has been known for some time that the geometry around an axisymmetric body can be described by its (Geroch-Hansen) multipole moments. Therefore one can speculate that using the multipole moments can prove to be a helpful tool for extracting this information. We will try to demonstrate this in this talk, following the procedure described by [F. D. Ryan, Phys. Rev. D {\bf 52} 5707 (1995)] and [T. P. Sotiriou and T. A. Apostolatos, Phys. Rev. D {\bf 71} 044005 (2005)].

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Thomas P. Sotiriou, Theocharis A. Apostolatos. 2006-11-06. Multipole moments as a tool to infer from gravitational waves the geometry around an axisymmetric body. https://doi.org/10.1063/1.2399654

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