Quote Originally Posted by mojo
It's a statistical thing. It doesn't exist in individual quantum mechanics interactions between particles. It's emergent when you look at many interactions.
At what point does entropy emerge? We can say with confidence that in a one-particle universe, there is no entropy. What about a two-particle universe? Given infinite time, will the two particles collide more than once? Will they collide an infinite number of times? Entropy seems to emerge when there are an infinite number of collisions over an infinite period of time, allowing energy to spread out evenly in the system. If gravity demands that the two particles will continue to interact and collide, then surely entropy exists in the two-particle universe. Maybe there's the link between gravity and entropy in its most basic form.