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arXiv · 1807.05011

Ghost-free infinite derivative gravity

Brage Gording·Angnis Schmidt-May
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Abstract

We present the construction of a gravitational action including an infinite series of higher derivative terms. The outcome is a classically consistent completion of a well-studied quadratic curvature theory. The closed form for the full action is ghost-free bimetric theory, describing the interactions of a massive and a massless spin-2 field. At energies much smaller than the spin-2 mass scale, the theory reduces to general relativity. For energies comparable to the spin-2 mass, the higher derivative terms completing the Einstein-Hilbert action capture the effects of the additional massive spin-2 field. The theory is only ghost-free when the full series of higher derivatives is kept.

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Brage Gording, Angnis Schmidt-May. 2018-07-13. Ghost-free infinite derivative gravity. https://doi.org/10.1007/jhep09(2018)044

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