Quantum isometry group of dual of finitely generated discrete groups - II
Annales Mathématiques Blaise Pascal, Tome 23 (2016) no. 2, pp. 219-247.

As a continuation of the programme of [13], we carry out explicit computations of $ℚ\left(\Gamma ,S\right)$, the quantum isometry group of the canonical spectral triple on ${C}_{r}^{*}\left(\Gamma \right)$ coming from the word length function corresponding to a finite generating set S, for several interesting examples of $\Gamma$ not covered by the previous work [13]. These include the braid group of 3 generators, ${ℤ}_{4}^{*n}$ etc. Moreover, we give an alternative description of the quantum groups ${H}_{s}^{+}\left(n,0\right)$ and ${K}_{n}^{+}$ (studied in [3], [4]) in terms of free wreath product. In the last section we give several new examples of groups for which $ℚ\left(\Gamma \right)$ turns out to be a doubling of ${C}^{*}\left(\Gamma \right)$.

DOI : https://doi.org/10.5802/ambp.361
Classification : 58B34,  46L87,  46L89
Mots clés: Compact quantum group, Quantum isometry group, Spectral triple
@article{AMBP_2016__23_2_219_0,
author = {Arnab Mandal},
title = {Quantum isometry group of dual of finitely generated discrete groups - II},
journal = {Annales Math\'ematiques Blaise Pascal},
pages = {219--247},
publisher = {Annales math\'ematiques Blaise Pascal},
volume = {23},
number = {2},
year = {2016},
doi = {10.5802/ambp.361},
language = {en},
url = {ambp.centre-mersenne.org/item/AMBP_2016__23_2_219_0/}
}
Arnab Mandal. Quantum isometry group of dual of finitely generated discrete groups - II. Annales Mathématiques Blaise Pascal, Tome 23 (2016) no. 2, pp. 219-247. doi : 10.5802/ambp.361. https://ambp.centre-mersenne.org/item/AMBP_2016__23_2_219_0/

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