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| public:t-720-atai:atai-22:task-environment [2022/09/01 11:40] – [Maxwell's Demon] thorisson | public:t-720-atai:atai-22:task-environment [2024/04/29 13:33] (current) – external edit 127.0.0.1 |
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| | {{public:t-720-atai:maxwellsdemon.png?500}} \\ Source: [[https://en.wikipedia.org/wiki/Maxwell%27s_demon|Wikipedia]] \\ By User:Htkym - Own work, CC BY 2.5, [[https://commons.wikimedia.org/w/index.php?curid=1625737|REF]] || | | {{public:t-720-atai:maxwellsdemon.png?500}} \\ Source: [[https://en.wikipedia.org/wiki/Maxwell%27s_demon|Wikipedia]] \\ By User:Htkym - Own work, CC BY 2.5, [[https://commons.wikimedia.org/w/index.php?curid=1625737|REF]] || |
| | \\ A Thought Experiment | Imagine a container divided into two parts, A and B. Both parts are filled with the same gas at equal temperatures and placed next to each other. Observing the molecules on both sides, an imaginary demon guards a trapdoor between the two parts. When a faster-than-average molecule from A flies towards the trapdoor, the demon opens it, and the molecule will fly from A to B. Likewise, when a slower-than-average molecule from B flies towards the trapdoor, the demon will let it pass from B to A. The average speed of the molecules in B will have increased while in A they will have slowed down. Since average molecular speed corresponds to temperature, the temperature decreases in A and increases in B, contrary to the second law of thermodynamics. A heat extractor operating between the thermal reservoirs A and B could extract energy from this temperature difference, creating a perpetual motion machine. [ Adapted from [[https://en.wikipedia.org/wiki/Maxwell%27s_demon|Wikipedia]] ] | | | \\ A Thought Experiment | Imagine a container divided into two parts, A and B. Both parts are filled with the same gas at equal temperatures and placed next to each other. Observing the molecules on both sides, an imaginary demon guards a trapdoor between the two parts. When a faster-than-average molecule from A flies towards the trapdoor, the demon opens it, and the molecule will fly from A to B. Likewise, when a slower-than-average molecule from B flies towards the trapdoor, the demon will let it pass from B to A. The average speed of the molecules in B will have increased while in A they will have slowed down. Since average molecular speed corresponds to temperature, the temperature decreases in A and increases in B, contrary to the second law of thermodynamics. A heat extractor operating between the thermal reservoirs A and B could extract energy from this temperature difference, creating a perpetual motion machine. [ Adapted from [[https://en.wikipedia.org/wiki/Maxwell%27s_demon|Wikipedia]] ] | |
| | \\ The Error | The thought experiment is flawed because the demon must be part of the same system that the container is part of; thinking (or computation, if the demon is a robot) requires time and energy, and so whatever heat is saved in the container will be spent to run the demon's thinking processes. (This was first proposed in [[/public:t-720-atai:szilard-1929-entropy-intelligent-beings.pdf|1929 by Leo Szilard]].) | | | \\ The Error | The thought experiment is flawed because the demon must be part of the same system that the container is part of; thinking (or computation, if the demon is a robot) requires time and energy, and so whatever heat is saved in the container will be spent to run the demon's thinking processes. (This was first proposed in {{/public:t-720-atai:szilard-1929-entropy-intelligent-beings.pdf|1929 by Leo Szilard}}.) | |
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