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arXiv · 1403.0619

von Neumann indices and classes of positive definite functions

Palle Jorgensen·Feng Tian
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Abstract

With view to applications, we establish a correspondence between two problems: (i) the problem of finding continuous positive definite extensions of functions $F$ which are defined on open bounded domains $Ω$ in $\mathbb{R}$, on the one hand; and (ii) spectral theory for elliptic differential operators acting on $Ω$, (constant coefficients.) A novelty in our approach is the use of a reproducing kernel Hilbert space $\mathscr{H}_{F}$ computed directly from $\left(Ω,F\right)$, as well as algorithms for computing relevant orthonormal bases in $\mathscr{H}_{F}$.

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Palle Jorgensen, Feng Tian. 2014-03-03. von Neumann indices and classes of positive definite functions. https://doi.org/10.1063/1.4895462

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