Compactness of Floquet isospectral sets for the matrix Hill’s equation

Carlson, Robert

doi:10.1090/S0002-9939-00-05634-3

Compactness of Floquet isospectral sets for the matrix Hill’s equation
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Proc. Amer. Math. Soc. 128 (2000), 2933-2941 Request permission

Abstract:

Let $\mathcal {M}(Q)$ denote the set of self adjoint $K \times K$ potentials for the matrix Hill’s equation having the same Floquet multipliers as $-D^2 + Q$. Elementary methods are used to show that $\mathcal {M}(Q)$ has compact closure in the space of continuous matrix valued functions.

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