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arXiv · 1903.04283

$pp$-waves as exact solutions to ghost-free infinite derivative gravity

Ercan Kilicarslan
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Abstract

We construct exact pp-wave solutions of ghost-free infinite derivative gravity and demonstrate that the sourceless theory does not bring any pp-wave solutions save for that of Einstein's gravity. These waves described in the Kerr-Schild form also solve the linearized field equations of the theory. We also find an exact gravitational shock wave with non-singular curvature invariants and with a finite limit in the ultraviolet regime of non-locality which is in contrast to the divergent limit in Einstein's theory.

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Ercan Kilicarslan. 2019-03-11. $pp$-waves as exact solutions to ghost-free infinite derivative gravity. https://doi.org/10.1103/physrevd.99.124048

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