11.3: System and Environment
- Page ID
- 50224
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The formulas to this point apply to the system if the summations are over the states of the system, and they also apply to the system and its environment if the summations are over the larger number of states of the system and environment together. (The magnetic-dipole model of Figure 11.1 even shows a system capable of interacting with either of two environments, a feature that is needed if the system is used for energy conversion.) Next are some results for a system and its environment interacting.