Low-energy effects in a higher-derivative gravity model with real and complex massive poles

Understand

The most simple superrenormalizable model of quantum gravity is based on the general local covariant six-derivative action.

• In addition to graviton such a theory has massive scalar and tensor modes.
• It was shown recently that in the case when the massive poles emerge in complex conjugate pairs, the theory has also unitary $S$-matrix and hence can be seen as a candidate to be a consistent quantum gravity theory.
• In the present work we construct the modified Newton potential and explore the gravitational light bending in a general six-derivative theory, including the most interesting case of complex massive poles.