Multiparameter deficiency index theory
Patrick J. Browne, Brian D. Sleeman · Applicable Analysis · 1988
Let Tr,Vrs be closed symmetric operators in the Hilbert space Hr with D(Tr) ⊂ D(Vrs), 1 ≤ r,s ≤k. Wefind sets of points such that has constant defect. The system of simultaneous equations , is linked to a set of one parameter problems in generated by decouplingthe eigen parameters.