I wish I had an elementary conceptual explanation for why this association exists. It's a simple calculation, but hard to describe without resorting to equatio

I wish I had an elementary conceptual explanation for why this association exists. It's a simple calculation, but hard to describe without resorting to equations. Maybe the best I can say is that when one writes down the energy function for a quantum mechanical system of many particles, it has a form which is _strongly_ constrained by special relativity. The variables which describe the creation of particles are perfectly paired with the variables which describe the annihilation of particles. For bosons, these variables commute, just like ordinary functions. For fermions, these variables anti-commute, picking up a sign when you exchange them. If you repeatedly exchange these variables to rewrite energy function as vacuum energy + energy of 1 particle + energy of 2 particles + ...., you discover that the fermions contribute negatively to the vacuum energy while bosons contribute positively.