2018/09/25 by Latushkin, Yuri, Sukhtaiev, Selim · 1 citation
#FOS: Mathematics #Spectral Theory (math.SP)
paper · doi:10.48550/arxiv.1809.09344
We show that the spectral flow of a one-parameter family of Schrödinger operators on a metric graph is equal to the Maslov index of a path of Lagrangian subspaces describing the vertex conditions. In addition, we derive an Hadamard-type formula for the derivatives of the eigenvalue curves via the Maslov crossing form.