On the computation of spectra and pseudospectra of self-adjoint and non-self-adjoint Schrödinger operators
نویسندگان
چکیده
We consider the long standing open question on whether one can actually compute spectra and pseudospectra of arbitrary (possibly non-self-adjoint) Schrödinger operators.We conclude that the answer is affirmative for “almost all” such operators, meaning that the operators must satisfy rather weak conditions such as the spectrum cannot be empty nor the whole plane. We include algorithms for the general problem, and also for operators with more structure, such as compactness of the resolvent and discrete Schrödinger operators.
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