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arXiv · 1703.03345

A Singular One-Dimensional Bound State Problem and its Degeneracies

F. Erman·M. Gadella·Ş. Tunalı·H. Uncu
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Abstract

We give a brief exposition of the formulation of the bound state problem for the one-dimensional system of $N$ attractive Dirac delta potentials, as an $N \times N$ matrix eigenvalue problem ($\Phi A =\omega A$). The main aim of this paper is to illustrate that the non-degeneracy theorem in one dimension breaks down for the equidistantly distributed Dirac delta potential, where the matrix $\Phi$ becomes a special form of the circulant matrix. We then give an elementary proof that the ground state is always non-degenerate and the associated wave function may be chosen to be positive by using the Perron-Frobenius theorem. We also prove that removing a single center from the system of $N$ delta centers shifts all the bound state energy levels upward as a simple consequence of the Cauchy interlacing theorem.

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F. Erman, M. Gadella, Ş. Tunalı, H. Uncu. 2017-03-09. A Singular One-Dimensional Bound State Problem and its Degeneracies. https://arxiv.org/abs/1703.03345

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