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arXiv · 2610.15771

An optimization problem for $δ'$ leaky stars

Pavel Exner
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Abstract

We consider singular Schrödinger operators with an attractive $δ'$ interaction of strength $β$ supported by a star graph and prove that the ground-state eigenvalue is uniquely maximized by stars of the maximum symmetry. Two different proofs are presented, one for an even number of edges using a comparison to the $δ$ interaction star, the other general based on Birman-Schwinger technique.

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Pavel Exner. 2026-10-11. An optimization problem for $δ'$ leaky stars. https://arxiv.org/abs/2610.15771

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