Linear cosmological perturbations in scalar-tensor-vector gravity

摘要

We investigate the cosmological perturbations in the context of a Scalar-Tensor-Vector theory of Gravity known as MOG in the literature. Recent investigations show that MOG reproduces a viable background cosmological evolution comparable to Lambda CDM. However, the matter dominated era is slightly different. In this paper, we study the linear matter perturbations and estimate the relevant modified gravity parameters. We show that MOG reduces the growth rate of the perturbations and comparing with the RSD data reveals that MOG suggests a higher value for sigma(8), compare to Lambda CDM. This point, constitute a powerful challenge to the cosmological viability of MOG. (C) 2020 The Author(s). Published by Elsevier B.V.