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arXiv · 2509.10643

Invariant subspace perturbations related to defective eigenvalues of $Δ$-Hermitian and Hamiltonian matrices

Hongguo Xu
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Abstract

Structured perturbation results for invariant subspaces of $Δ$-Hermitian and Hamiltonian matrices are provided. The invariant subspaces under consideration are associated with the eigenvalues perturbed from a single defective eigenvalue. The results show how the original eigenvectors and generalized eigenvectors are involved in composing such perturbed invariant subspaces and eigenvectors.

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Hongguo Xu. 2026-01-28. Invariant subspace perturbations related to defective eigenvalues of $Δ$-Hermitian and Hamiltonian matrices. https://arxiv.org/abs/2509.10643

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