Negative definite functions for C*-dynamical systems

Erik Bedos; Roberto Conti

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arXiv · 1612.03309

Negative definite functions for C*-dynamical systems

Erik Bedos·Roberto Conti

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Abstract

Given an action $\alpha$ of a discrete group $G$ on a unital C*-algebra $A$, we introduce a natural concept of $\alpha$-negative definiteness for functions from $G$ to $A$, and examine some of the first consequences of such a notion. In particular, we prove analogs of theorems due to Delorme-Guichardet and Schoenberg in the classical case where $A$ is trivial. We also give a characterization of the Haagerup property for the action $\alpha$ when $G$ is countable.

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BibTeX RIS

Erik Bedos, Roberto Conti. 2016-12-10. Negative definite functions for C*-dynamical systems. https://arxiv.org/abs/1612.03309

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