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arXiv · 1510.00692

Faithful actions of locally compact quantum groups on classical spaces

Debashish Goswami·Sutanu Roy
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Abstract

It is well-known that no non-Kac compact quantum group can faithfully act on $C(X)$ for a classical, compact Hausdorff space $X$. However, in this article we show that this is no longer true if we go to non-compact spaces and non-compact quantum groups, by exhibiting a large class of examples of locally compact quantum groups coming from bicrossed product construction, including non-Kac ones, which can faithfully and ergodically act on classical (non-compact) spaces. However, none of these actions can be isometric in the sense of Goswami, leading to the conjecture that the result obtained by Goswami and Joardar about non-existence of genuine quantum isometry of classical compact connected Riemannian manifolds may hold in the non-compact case as well.

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Debashish Goswami, Sutanu Roy. 2015-10-02. Faithful actions of locally compact quantum groups on classical spaces. https://doi.org/10.1007/s11005-017-0951-1

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