Abstract
We study light bending by the sun in the optical frequencies range using Yang-Mills gravity, which is based on spacetime translational (T₄) gauge symmetry in inertial frames. This approach provides an effective metric tensor Gμᵥ(𝔁) for classical objects and light rays. The deflection of light angle is calculated to be δϕ ≈ 1.75′′ in inertial frames without requiring a gauge condition. If the theory is U1 gauge invariant, a different angle of deflection δϕ ≈ 1.53′′ is obtained, but experimental precision cannot rule out either result. The Big Jets model for the beginning of the universe is discussed. It involves two oppositely directed jets, which cooled down and evolved into a matter blackbody (or matter half-universe) and an antimatter blackbody. Both emit microwaves. They suggest the existence of a very weak hemispheric anisotropy in our observed cosmic microwave background. Yang-Mills gravity provides a new perspective on light bending and cosmic expansion. Although experimental limitations hinder definitive conclusions, future research may refine our understanding of Yang-Mills gravity and its implications at the super-macroscopic scales.