Examples of positive operators in Krein space with 0 a regular critical point of infinite rank
Branko Ćurgus, Branko Najman · Birkhäuser Basel eBooks · 1998
It is shown that the operators associated with the perturbed wave equation in ℝ n and with elliptic operators with an indefinite weight function and mildly varying coefficients on ℝ n are similar to a self-adjoint operator in a Hilbert space. These operators have the whole ℝ n as the spectrum. It is shown that they are positive operators in corresponding Krein spaces, and the whole problem is reduced to showing that 0 is not a singular critical point. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.