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arXiv · 0811.1781

Decomposition of geometric perturbations

Roman V. Buniy·Thomas W. Kephart
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Abstract

For an infinitesimal deformation of a Riemannian manifold, we prove that the scalar, vector, and tensor modes in decompositions of perturbations of the metric tensor, the scalar curvature, the Ricci tensor, and the Einstein tensor decouple if and only if the manifold is Einstein. Four-dimensional space-time satisfying the condition of the theorem is homogeneous and isotropic. Cosmological applications are discussed.

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Roman V. Buniy, Thomas W. Kephart. 2008-11-12. Decomposition of geometric perturbations. https://doi.org/10.1016/j.physletb.2009.03.043

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