Uniformity and isotypic smallness for quantum-group representations

Alexandru Chirvasitu

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arXiv · 2603.24855

Uniformity and isotypic smallness for quantum-group representations

Alexandru Chirvasitu

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Abstract

Compact-group representations on Banach spaces are known to be norm-continuous precisely when they have finite spectra. For a quantum group with continuous-function algebra $\mathcal{C}(\mathbb{G})$ norm continuity can be cast analogously as the bounded weak$^*$-norm continuity of the representation's attached maps $\mathcal{C}(\mathbb{G})^*\to \mathrm{End}(E)$ and its mirror counterpart $E_{\le 1}\times E^*_{\le 1}\to \mathcal{C}(\mathbb{G})$. While the uniformity/isotypic finiteness equivalence no longer holds generally, it does (for the latter map) for compact quantum groups either coamenable or having dimension-bounded irreducible representations. This generalizes the aforementioned classical variant, providing two independent quantum-specific mechanisms of recovering it.

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BibTeX RIS

Alexandru Chirvasitu. 2026-03-25. Uniformity and isotypic smallness for quantum-group representations. https://arxiv.org/abs/2603.24855

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