I am fairly new to QM and am learning many of the basics right now. We were just discussing conservation of operators (energy, momentum, etc) and I recalled a problem proposed in my textbook about a 1D particle in a box of length L. at a time t, the box suddenly expands to t=2L, in which time the wavefunction does not have time respond. it asked if energy (more specifically, <H>) was conserved during the time that the wall moves.(adsbygoogle = window.adsbygoogle || []).push({});

i'm assuming that the laws of conservation aren't broken and that the Hamiltonian does not change. but then does the fact that the box expanded at a specific time, mean that then the potential V(x) is now a function of time? so then is energy is not conserved since I have to consider the potential in the Hamiltonian now?

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# Energy Conservation in an expanded 1D box

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