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arXiv · 1512.07600

Superrenormalizable quantum gravity with complex ghosts

Leonardo Modesto·Ilya L. Shapiro
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Abstract

We suggest and briefly review a new sort of superrenormalizable models of higher derivative quantum gravity. The higher derivative terms in the action can be introduced in such a way that all the unphysical massive states have complex poles. According to the literature on Lee-Wick quantization, in this case the theory can be formulated as unitary, since all massive ghosts-like degrees of freedom are unstable.

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Leonardo Modesto, Ilya L. Shapiro. 2016-02-11. Superrenormalizable quantum gravity with complex ghosts. https://doi.org/10.1016/j.physletb.2016.02.021

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