On the spectral theory of systems of first order equations with periodic distributional coefficients

Kevin Campbell; Rudi Weikard

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arXiv · 2301.07212

On the spectral theory of systems of first order equations with periodic distributional coefficients

Kevin Campbell·Rudi Weikard

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Abstract

We establish a Floquet theorem for a first-order system of differential equations $u'=ru$ where $r$ is an $n\times n$-matrix whose entries are periodic distributions of order $0$. Then we investigate, when $n=1$ and $n=2$, the spectral theory for the equation $Ju'+qu=wf$ on $\mathbb R$ when $J$ is a real, constant, invertible, skew-symmetric matrix and $q$ and $w$ are periodic matrices whose entries are real distributions of order $0$ with $q$ symmetric and $w$ non-negative.

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BibTeX RIS

Kevin Campbell, Rudi Weikard. 2023-01-17. On the spectral theory of systems of first order equations with periodic distributional coefficients. https://arxiv.org/abs/2301.07212

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