An isoperimetric problem for point interactions
arXiv:math-ph/0406017 · doi:10.1088/0305-4470/38/22/004
Abstract
We consider Hamiltonian with point interactions in all with the same coupling constant, placed at vertices of an equilateral polygon $\PP_N$. It is shown that the ground state energy is locally maximized by a regular polygon. The question whether the maximum is global is reduced to an interesting geometric problem.
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