Griesemer, Marcel; Lewis, Roger T.; Siedentop, Heinz
A minimax principle for eigenvalues in spectral gaps: Dirac operators with Coulomb potentials.
Doc. Math., J. DMV 4, 275-283 (1999)
Summary
Summary: We prove the minimax principle for eigenvalues in spectral gaps introduced in citeGriesemerSiedentop1999 based on an alternative set of hypotheses. In the case of the Dirac operator these new assumptions allow for potentials with Coulomb singularites.