Basic Information
Maxwell's Demon is a famous thought-experiment by James Clerk Maxwell, suggesting a way in which the second law of thermodynamics might be broken. In the thought-experiment, there are two chambers containing particles of various speeds, connected by a small hole. The titular demon sits near this hole watching the particles, and sorts the particles into the different rooms (fast particles into one room, slow particles into the other) by opening and closing the hole as a particle approaches.
Of course, if this actually worked, someone would have used it for power generation by now, since this would create a hot chamber and a cold chamber that could be used to drive a turbine. The problem is that in order to sort the particles, the "demon" needs to observe each particle, which due to quantum effects would both draw energy and alter the speed of the particles.
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Game and Story Use
- In a techno-magic setting, having a small demonic entity regulating a power generator might be practical.
- Of course since you'd have to sign away your soul to get him to do the job, you might not exactly be getting free energy.
