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arXiv · 1209.6508

Contractive idempotents on locally compact quantum groups

Matthias Neufang·Pekka Salmi·Adam Skalski·Nico Spronk
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Abstract

A general form of contractive idempotent functionals on coamenable locally compact quantum groups is obtained, generalising the result of Greenleaf on contractive measures on locally compact groups. The image of a convolution operator associated to a contractive idempotent is shown to be a ternary ring of operators. As a consequence a one-to-one correspondence between contractive idempotents and a certain class of ternary rings of operators is established.

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Matthias Neufang, Pekka Salmi, Adam Skalski, Nico Spronk. 2013-03-07. Contractive idempotents on locally compact quantum groups. https://arxiv.org/abs/1209.6508

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