Is geothermal every mainly fission? I thought it was mostly residual heat from earth's formation. In your picture it is also expansion. Here I disagree because your argument only holds for hydrogen and helium. Everything else comes from exploding stars so the mass distribution of the earth (and moon) is also nuclear's wrongdoing.
post
While not super relevant to earth, black holes are thought to slowly convert their mass into energy and radiate it off over a very long time (slower the bigger the thing is). Since what they are made of can't really be described as atoms anymore, this isn't really a nuclear process, and as far as I'm aware, this isn't driven by the universe's continued expansion either.
Hmm yeah you're right, it's not directly a nuclear process nor is it driven by cosmic expansion, but it's still somehow related to mechanical energy (i think), since basically black holes use their enormous gravitational force gradient to basically rip the vacuum apart and that way release energy. And gravitational energy is a kind of mechanical energy, i'd say.
Yes absolutely true. I've thought about this before. Thank you for explaining it so clearly
all 5 comments