Indefinite Sturm-Liouville operators in polar form

Branko Ćurgus, Volodymyr Derkach, Carsten Trunk

We consider the indefinite Sturm-Liouville differential expression \[\mathfrak{a}(f) := - \frac{1}{w}\left( \frac{1}{r} f' \right)',\] where $\mathfrak{a}$ is defined on a finite o…