Minimal extension of Einstein’s gravity at the quartic order

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2018
Kenar, Esin
We study an extension of Einstein general relativity theory at the quartic order in the curvature. The extended theory has a unique vacuum and a single massless spin-2 excitation about this vacuum, just like general relativity, hence it is called a minimal extension. The extended theory can also be obtained from a particular form of Born-Infeld gravity. We show that the Schwarzschild and Kerr black holes are not exact solutions and the Kretschmann scalar obeys a non-linear wave equation, suggesting that black hole singularities might be avoided.

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Citation Formats
E. Kenar, “Minimal extension of Einstein’s gravity at the quartic order,” Ph.D. - Doctoral Program, Middle East Technical University, 2018.