Thought: then measure it in motion. aim a constant beam of light at a super sensitie scale and see if it records any weight. if the answer is zero - then it weights nothing. if it weights XYZ, then it weights something. math can determin how much each particle of light weights.
Second thought: black holes have so much density - and such a strong gravitational pull - that =nothing= escapes it - including light.
Questions: Does light need weight to be influenced by gravity? If light has no weight, would it give the metaphorical bird to gravity in passing, or would it be trapped and pulled in, like everything else? Does gravity work on things that weigh nothing? Is light drawn to earth due to the earths gravity, or does it go by the earth, because the earth was simply in its way?
2. black holes and light
thought: black holes have the 'event horizon' where, just before anything actually falls into the hole, everything "seems/is percived" to freeze and stretch out in time. Including light. Light stretches out into the red specrum, becoming 'invisible', as it were.
questions: is light truely trapped? Or have we just not yet seen how it escapes (or drives by)? (re: if light weighs nothing, is the black hole simply in its way?)
3. Black hole
thoughts: What if black holes are more than 'needy stars' - that only take, but never give? What if black holes process everything it captures and compresses, and releases it back out? But we don't see it - for example, black matter. What if black holes are the earth equivalent of volcanoes that form new 'matter'?
...and such, I think about on a lazy sunday afternoon.