My first post! Bear with me here - I'm a weekend warrior of particle physics and am just learning because it amazes me. In my journey through nuclear fusion and quantum theory, I first learned that our sun isn't big enough to overcome the Coulomb barrier between two protons necessary to allow them to fuse, that the basic force of gravity isn't enough, (Insert need for quantum fields here etc). Then I later read that the sun also isn't hot enough at the core, (the first article never mentioned heat...), and that both heat and gravity are necessary for fusion. My question is, what is heat then? If temperature can slow down or speed up particle movement, then why isn't it a basic force? I learned that something as simple as the strong nuclear force is caused by the transfer of gluons, what sub-atomic particle causes temperature change then? Go easy on me, but not too easy. My IQ hovers around 120, but when I want to learn something I'm relentless.