The densely packed, standing ovoids of light are autonomous. When an ovoid is pushed over by people, it stands back up while the color of its light changes, and it emits a sound tone specific to that color. The surrounding ovoids respond one by one, continuously changing to the same color and emitting the same tone.
If a wave of light comes from the ovoids on the opposite side, it signifies that there is another person there. Perhaps people will become more aware of the existence of others in the same space.