Process:  - The gravity of the sun pulls its mass inward - There is a lot of pressure on the Sun - The pressure forces atoms of hydrogen to fuse together in nuclear reactions - The energy from the reactions gives off different kinds of light - The light travels to the Earth.  Perturbation hypothesis: suppose less gravity to pull happens, how will it affect LESS sunlight arriving at the Earth.  Does the supposed perturbation have an effect (direct or indirect) on the process?

yes