The quantum square well with moving boundaries: A numerical analysis

We present some numerical discussions concerning the infinite square well in one dimension with moving boundaries. Our results show that if the speed of displacement is small, objects of physical relevance like probability density, averaged position or mean value of the energy have a smooth behavior. On the contrary, if this speed becomes large, many irregularities arise, which has a difficult qualitative explanation. These irregularities manifest themselves as sharp bumps on the probability distribution or a chaotic shape on the averaged values of position and energy. None of these patterns is the result of numerical errors and, therefore, we conclude that an unknown and very nontrivial effect is produced at high speeds of the moving wall.

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