Scalar and Vector Field Constraints, Deflection of Light and Lensing in Modified Gravity (MOG)

Understand

A conformal coupling of the metric in the Jordan frame to the energy-momentum tensor, screens the scalar field gravitational coupling strength $G$ in modified gravity (MOG).

• The scalar field acquires a mass which depends on the local matter density: the scalar field particle is massive for the Sun and earth, where the density is high compared to low density environments in cosmology and astrophysics.
• Together with the screening of the vector field $\phi_\mu$, this guarantees that solar system tests of gravity are satisfied.
• The conformal metric is coupled to the electromagnetic matter field and energy-momentum tensor, screening $G$ for the Sun and the deflection of light by the Sun and the Shapiro time delay in MOG are in agreement with general relativity.