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Can matter be created in a pure vacuum (with no energy)? It's a subtle question. Firstly, how do we know whether there is energy? But even if there were energy if it was a minimum of energy then you wouldn't be able to use it to make things, and the energy minimum would be considered a good vacuum. But can you make particles? If they just appeared ...


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Given the persistence of this kind of thing, maybe determining the misconceptions underlying it are not so easy to determine and resolve. [Given that we're talking about physics students, I guess it's fair to them to sort this out rather than ignore as one might otherwise.] For my money, I'd ask whether within each part of the mechanism Newton's Third Law ...


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I was not able to convince him that this propulsion drive cannot work due to conservation of momentum. Am I wrong about that? No, you are not wrong. It's clear that the engine cannot work because of momentum conservation. It's basically just a fixed double pendulum. Why should there be any positive momentum in any direction after one full circle? ...



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