In particular, the case of A −1 ∈ S∞(H), asymptotic estimates of normal extensions of eigenvalues has been established at infinity.
📌 3 Key Takeaways
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Objective & Hypothesis:In the Hilbert space of vector-functions L 2 (H,(a, b)), where H is any separable Hilbert space, the general representation in terms of boundary values of all normal extensions of the formally normal minimal operator, generated by linear differential-operator expressions of third order in the form l(u) = u ′′′(t) + A 3 u(t), A : D(A) ⊂ H → H, A = A ∗ ≥ E, is obtained in the first part of this study.
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Key Findings & Data:Then, some spectral properties of these normal extensions are investigated.
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Conclusion & Impact:In particular, the case of A −1 ∈ S∞(H), asymptotic estimates of normal extensions of eigenvalues has been established at infinity.
In the Hilbert space of vector-functions L 2 (H,(a, b)), where H is any separable Hilbert space, the general representation in terms of boundary values of all normal extensions of the formally normal minimal operator, generated by linear differential-operator expressions of third order in the form l(u) = u ′′′(t) + A 3 u(t), A : D(A) ⊂ H → H, A = A ∗ ≥ E, is obtained in the first part of this study. Then, some spectral properties of these normal extensions are investigated. In particular, the case of A −1 ∈ S∞(H), asymptotic estimates of normal extensions of eigenvalues has been established at infinity.
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