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arXiv · 1809.05907

Effective delta sources and regularity in higher-derivative and ghost-free gravity

Breno L. Giacchini·Tibério de Paula Netto
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Abstract

It is shown that polynomial gravity theories with more than four derivatives in each scalar and tensor sectors have a regular weak-field limit, without curvature singularities. This is achieved by proving that in these models the effect of the higher derivatives can be regarded as a complete regularization of the delta-source. We also show how this result implies that a wide class of non-local ghost-free gravities have a regular Newtonian limit too, and discuss the applicability of this approach to the case of weakly non-local models.

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Breno L. Giacchini, Tibério de Paula Netto. 2018-09-16. Effective delta sources and regularity in higher-derivative and ghost-free gravity. https://doi.org/10.1088/1475-7516%2F2019%2F07%2F013

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