Stability of eigenvalues of quantum graphs with respect to magnetic perturbation and the nodal count of the eigenfunctions

Autor: Berkolaiko, G., Weyand, T.
Rok vydání: 2012
Předmět:
Zdroj: Phil. Trans. Roy. Soc. A. 372, 1471-2962 (2014)
Druh dokumentu: Working Paper
DOI: 10.1098/rsta.2012.0522
Popis: We prove an analogue of the magnetic nodal theorem on quantum graphs: the number of zeros $\phi$ of the $n$-th eigenfunction of the Schr\"odinger operator on a quantum graph is related to the stability of the $n$-th eigenvalue of the perturbation of the operator by magnetic potential. More precisely, we consider the $n$-th eigenvalue as a function of the magnetic perturbation and show that its Morse index at zero magnetic field is equal to $\phi - (n-1)$.
Comment: 19 pages, 3 figures
Databáze: arXiv