For example, evenly shoot 10000 lines from the core, and make a sphere with the core point as the center at any distance. All lines passing through this sphere are 10000. Since the surface area of a sphere is proportional to the square of the radius, the linear density on the sphere is inversely proportional to the radius. This is why gravity and electric field strength are inversely proportional to distance.
2. The medium through which gravity and electric field propagate is the same substance.
This substance and the propagation of light are the same substance. Although scientists have not proved the existence of this medium through experiments, it does not mean that there is no such substance. I have explained in the previous article that the failure of Michelson-Morey experiment is due to the wrong experimental method and environment, just like holding a windmill in a closed car and trying to prove whether the car is moving through the rotation of the windmill, it is doomed to failure. The matter around the sun rotates with the sun, the matter around the earth rotates with the earth, the matter around the nucleus rotates with the nucleus, and the matter around the electron rotates with the electron.
The change of gravity intensity with distance is the embodiment of scalar property of this material, that is, the embodiment of density change; The change of electric field intensity with distance is the embodiment of the vector property of this substance, that is, the change of polarity density. In the electric field, not only the density changes, but also the polarity of matter becomes regular, and with the increase of electric field intensity, the polarity arrangement becomes more regular.
The speed of light is changing everywhere, where is there a real vacuum? Even inside an atom, there will be nothing but electrons, right? Why does light slow down in glass? Why is there a refractive index?
Quite simply, the density of light propagation media in materials such as glass is relatively high.
Gravity, electric field, magnetic field, light, etc. , are the same substance, are different properties of this substance. We are all familiar with another manifestation of this substance, that is, energy, which can also be transformed into familiar substances.