3: Ergodicity and the Approach to Equilibrium
- Page ID
- 18560
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- 3.3: Irreversibility and Poincaré Recurrence
- The dynamics of the master equation describe an approach to equilibrium. These dynamics are irreversible: dH/dt≤0 , where H is Boltzmann’s H -function. However, the microscopic laws of physics are (almost) time-reversal invariant, so how can we understand the emergence of irreversibility?
Thumbnail: Time evolution of two immiscible fluids. The local density remains constant.