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arXiv · 1308.2319

Generalized ghost-free quadratic curvature gravity

Tirthabir Biswas·Aindriú Conroy·Alexey S. Koshelev·Anupam Mazumdar
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Abstract

In this paper we study the most general covariant action of gravity up to terms that are quadratic in curvature. In particular this includes non-local, infinite derivative theories of gravity which are ghost-free and exhibit asymptotic freedom in the ultraviolet. We provide a detailed algorithm for deriving the equations of motion for such actions containing an arbitrary number of the covariant D'Alembertian operators, and this is our main result. We also perform a number of tests on the field equations we derive, including checking the Bianchi identities and the weak-field limit. Lastly, we consider the special subclass of ghost and asymptotically free theories of gravity by way of an example.

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Tirthabir Biswas, Aindriú Conroy, Alexey S. Koshelev, Anupam Mazumdar. 2013-08-10. Generalized ghost-free quadratic curvature gravity. https://doi.org/10.1088/0264-9381%2F31%2F1%2F015022

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