Densely defined non-closable curl on carpet-like metric measure spaces

Michael Hinz; Alexander Teplyaev

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arXiv · 1505.02819

Densely defined non-closable curl on carpet-like metric measure spaces

Michael Hinz·Alexander Teplyaev

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Abstract

The paper deals with the possibly degenerate behaviour of the exterior derivative operator defined on $1$-forms on metric measure spaces. The main examples we consider are the non self-similar Sierpinski carpets recently introduced by Mackay, Tyson and Wildrick. Although topologically one-dimensional, they may have positive two-dimensional Lebesgue measure and carry nontrivial $2$-forms. We prove that in this case the curl operator (and therefore also the exterior derivative on $1$-forms) is not closable, and that its adjoint operator has a trivial domain. We also formulate a similar more abstract result. It states that for spaces that are, in a certain way, structurally similar to Sierpinski carpets, the exterior derivative operator taking $1$-forms into $2$-forms cannot be closable if the martingale dimension is larger than one.

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BibTeX RIS

Michael Hinz, Alexander Teplyaev. 2016-11-16. Densely defined non-closable curl on carpet-like metric measure spaces. https://arxiv.org/abs/1505.02819

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