A photon is the smallest piece of light. Each drawing here is one photon trapped, like before.
The drawing on the right swooshes its waves out across all the space. Big waves up close, smaller and smaller far away.
The masses to the left are surfing those waves. The side near the big drawing always rides a bigger wave than the side far away. So closest wins!
Each little mass drawing wears dark green where space is squeezed shortest, the side by the other mass, and yellow where space runs longest farther out.
Opposite spin direction or "charges" surf toward each other. Same spin directions they surf apart.