Comment on "A modified scalar-tensor-vector gravity theory and the constraint on its parameters" by Deng, et al

TL;DR

This paper critiques a recent derivation of Eddington-Robertson parameters in a modified gravity theory, emphasizing the importance of the vector field that was previously overlooked.

Contribution

It clarifies the role of the vector field in deriving parameters of the MOG theory, correcting prior assumptions.

Findings

Explicit calculation shows the vector field's significance.

Previous derivations omitted the vector field's role.

Corrected derivation impacts the understanding of MOG parameters.

Abstract

We comment on a recent paper by Deng et al. (Phys. Rev. D 79, 044014 (2009), arXiv:0901.3730) in which the Eddington-Robertson parameters for our modified gravity theory (MOG) are derived. We show by explicit calculation that the role of the vector field $\phi_\mu$ cannot be ignored in this derivation.