Lasers are used to propel satellites, so light (radiant pressure) exerts force.
The cosmos emits radiant pressure from all directions & mass hit from all directions turns into a sphere.
Large masses shield smaller masses from radiant pressure and objects move towards the place with less pressure.
I don’t have the exact opacity per millimeter statistics, but I’ve ordered a few materials from least opaque to most opaque which coincidentally ordered them from lightest to heaviest too.
Weight per ft3:
Air = .08 lb per ft3
Water = 62 lb per ft3
Steel = 489 lb per ft3
My theory is that material weight is caused by its opacity (and reflectivity) catching the force of radiant pressures (light force) from the cosmos like a solar sail.
It’s a testable theory… Perhaps a lead chamber of extreme thickness could block out enough electromagnetic radiation to reduce gravity inside the room by a measurable amount.
I’d love to hear your thoughts.