The theory of the dynamic medium of reference has already been presented in several articles [Pignard, Phys. Essays 32, 422 (2019); 33, 395 (2020); 34, 61 (2021); 34, 279 (2021)], and in particular in Pignard, Phys. Essays 32, 422 (2019). The article
[Pignard, Phys. Essays 34, 279 (2021)] gives an explanation and mathematical developments of the gravitational acceleration from atomic nuclei of a massive body. General relativity considers a massive body, like the Earth or the Sun, globally, macroscopically, simply as an object of
mass M (which curves space‐time). However, when one goes into details, this mass M is made up of atoms which are themselves mainly made up of nuclei of nucleons (if we neglect the mass of electrons in comparison of that of the nucleus). Thus, it is mainly the nuclei of a massive
body that create the force of gravity! The dynamic medium of reference theory determines the gravitational acceleration microscopically by taking into account all the atomic nuclei that make up a massive body [Pignard, Phys. Essays 32, 422 (2019)]. This creates a strong link
between gravity and the nuclear domain. This article goes further with the description of a model of the atomic nucleus. This makes it possible to establish that the strong force or nuclear force, which ensures the cohesion of the nucleus, is due to the strong acceleration of the flux
of the medium which is a vector average of the flux of gravitons. This gives an expression of the nuclear force similar to the force of gravity but with a constant K ≈ 1031 m s−2, much higher than the gravitational constant G. This article shows that
the functioning, the mechanism of the nucleus, makes it possible to explain the nuclear force and also to find the gravitational acceleration. From there, it is deduced that the photons are deflected by the strong acceleration due to an atom nucleus. They are also slowed down by an atom nucleus
which creates a delay in their travel time which we call the nuclear time delay of light. Finally, an experiment is proposed to verify the phenomenon of nuclear deflection of light and the nuclear time delay of light.