Self-adjoint curl operators

R. Hiptmair; P. R. Kotiuga; S. Tordeux

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arXiv · 0809.0826

Self-adjoint curl operators

R. Hiptmair·P. R. Kotiuga·S. Tordeux

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Abstract

We study the exterior derivative as a symmetric unbounded operator on square integrable 1-forms on a 3D bounded domain $D$. We aim to identify boundary conditions that render this operator self-adjoint. By the symplectic version of the Glazman-Krein-Naimark theorem this amounts to identifying complete Lagrangian subspaces of the trace space of H(curl) equipped with a symplectic pairing arising from the $\wedge$-product of 1-forms on $\partial D$. Substantially generalizing earlier results, we characterize Lagrangian subspaces associated with closed and co-closed traces. In the case of non-trivial topology of the domain, different contributions from co-homology spaces also distinguish different self-adjoint extension. Finally, all self-adjoint extensions discussed in the paper are shown to possess a discrete point spectrum, and their relationship with curl curl-operators is discussed.

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BibTeX RIS

R. Hiptmair, P. R. Kotiuga, S. Tordeux. 2008-09-04. Self-adjoint curl operators. https://arxiv.org/abs/0809.0826

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