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arXiv · 1710.01764

A candidate for an UV completion: quadratic gravity in first order formalism

Enrique Alvarez·Jesus Anero·Sergio Gonzalez-Martin·Raquel Santos-Garcia
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Abstract

We consider the most general action for gravity which is quadratic in curvature. In this case first order and second order formalisms are not equivalent. This framework is a good candidate for a unitary and renormalizable theory of the gravitational field; in particular, there are no propagators falling down faster than $\tfrac{1}{p^2}$. The UV regime is in a conformal invariant phase; only when Weyl invariance is broken through the coupling to matter can an Einstein-Hilbert term (and its corresponding Planck mass scale) be generated.

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Enrique Alvarez, Jesus Anero, Sergio Gonzalez-Martin, Raquel Santos-Garcia. 2017-10-04. A candidate for an UV completion: quadratic gravity in first order formalism. https://arxiv.org/abs/1710.01764

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