Minimal extension of Einstein’s gravity at the quartic order

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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In order to obtain energy and momentum (due to matter and fields including gravitation) distributions of the Gibbons-Maeda dilaton spacetime, we use the Moller energy-momentum prescription both in Einstein"s theory of general relativity and teleparallel gravity. We find the same energy distribution for a given metric in both of these different gravitation theories. Under two limits, we also calculate energy associated with two other models such as the Garfinkle-Horowitz-Strominger dilaton spacetime and the ...
Citation Formats
E. Kenar, “Minimal extension of Einstein’s gravity at the quartic order,” Ph.D. - Doctoral Program, Middle East Technical University, 2018.