Yeah, gravity is an effect of masses trying to get to a state with less potential energy. Right. Now that we have explained gravity, it would be nice to explain why trying-to-getting-to-a-state-with-less-potential-energy happens.
Minimizing potential energy increases entropy. Aside from it being the second law of thermodynamics, why does entropy matter? Entropy just means that all energy tends to even out. If you put a hot plate on a cold surface, the plate will get cooler and the surface will get warmer.
To have this apply to masses seems contradictory. Masses don’t try to even out; they try to clump together. Now you have to ask what a mass is.
A spherical mass is totally not like a soap bubble. If you have a floating soap bubble, there’s air both outside and inside, and the difference in density is balanced by the molecular attraction of the soap film. The density of the air on the inside is less because it’s warmer; otherwise, it wouldn’t float. It wouldn’t balance the weight of its soap film. So it’s like a little hot-air balloon.
Anyway, a mass is denser than the non-mass around it.
It’s always important to continue to ask, “Yes, but why is that?” My folks don’t ask questions like this, which explains why they don’t understand me. I can’t help it. Well, I mean that I wouldn’t be myself if I behaved as though I weren’t a physics nerd. I wouldn’t feel better; I would feel worse. I could go on talking like this for hours, until you fell asleep. Maybe you’re already asleep.
Monologues