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arXiv · 1611.08382

Conditionally positive definite kernels in Hilbert $C^*$-modules

Mohammad Sal Moslehian
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Abstract

We investigate the notion of conditionally positive definite in the context of Hilbert $C^*$-modules and present a characterization of the conditionally positive definiteness in terms of the usual positive definiteness. We give a Kolmogorov type representation of conditionally positive definite kernels in Hilbert $C^*$-modules. As a consequence, we show that a $C^*$-metric space $(S, d)$ is $C^*$-isometric to a subset of a Hilbert $C^*$-module if and only if $K(s,t)=-d(s,t)^2$ is a conditionally positive definite kernel. We also present a characterization of the order $K'\leq K$ between conditionally positive definite kernels.

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Mohammad Sal Moslehian. 2016-11-25. Conditionally positive definite kernels in Hilbert $C^*$-modules. https://arxiv.org/abs/1611.08382

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