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Acta Polytechnica

Quantum graphs featuring unusual self-adjoint extensions

Pavel Exner

Published Nov 7, 2025• 0 citations
Publisher

Abstract

We present an example of a simple quantum graph with “vertices at infinity”, which appear due a strongly attractive potential making the spectral problem quantum-mechanically incomplete. We construct the appropriate self-adjoint extensions of the formal graph Hamiltonian, and derive their spectral properties.
DOI
10.14311/ap.2025.65.0539

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