Gravity is induced electrostatic force between matters/masses. 

Matter is formed by charges. 

Light/EM wave is the vibration electrostatic force/AC current produced by vibrating atoms/electrons. 

Atoms are solid spheres, therefore atoms are not build by empty spaces or electron clouds. 

Hydrogen atom is build by proton surround by enertron ball, electron is attracted by proton and repelled by enertron ball and balance at atom radius. 

Proton carries 918 positive charge, enertron carries very tiny negative charge but has higher charge to size ratio than electron. proton attracted 917 negative charge of enertrons to form a solid ball and add 1 negative charged electron on the surface to form hydrogen atom.

The density of the enertron ball is inversely proportional to distance cube, due to the attraction force between proton and enertron is inversely proportional to distance square. 

Electron is attracted by proton f=918x1/rr and repelled by enertron ball f=917x1/rrr, where r is atom radius. 

All atoms are constantly vibrate due to the unbalance of the 2 forces.

Every atom is an AC generator, electron moves closer and away from nucleus under the two forces,