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arXiv · 0902.3064

Coleff-Herrera currents, duality, and Noetherian operators

Mats Andersson
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Abstract

Let $\I$ be a coherent subsheaf of a locally free sheaf $\Ok(E_0)$ and suppose that $\F=\Ok(E_0)/\I$ has pure codimension. Starting with a residue current $R$ obtained from a locally free resolution of $\F$ we construct a vector-valued Coleff-Herrera current $μ$ with support on the variety associated to $\F$ such that $ϕ$ is in $\I$ if and only if $μϕ=0$. Such a current $μ$ can also be derived algebraically from a fundamental theorem of Roos about the bidualizing functor, and the relation between these two approaches is discussed. By a construction due to Björk one gets Noetherian operators for $\I$ from the current $μ$. The current $R$ also provides an explicit realization of the Dickenstein-Sessa decomposition and other related canonical isomorphisms.

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Mats Andersson. 2011-08-23. Coleff-Herrera currents, duality, and Noetherian operators. https://arxiv.org/abs/0902.3064

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