Hamiltonian Square Roots of Skew-Hamiltonian Matrices
نویسندگان
چکیده
We present a constructive existence proof that every real skew-Hamiltonian matrix W has a real Hamiltonian square root. The key step in this construction shows how one may bring any such W into a real quasi-Jordan canonical form via symplectic similarity. We show further that every W has infinitely many real Hamiltonian square roots, and give a lower bound on the dimension of the set of all such square roots. Some extensions to complex matrices are also presented. AMS subject classification. 15A21, 15A24, 15A57, 65F30, 93B10
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تاریخ انتشار 1999