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On the structure of quantum automorphism groups

  • Christian Voigt EMAIL logo

Abstract

We compute the K-theory of quantum automorphism groups of finite-dimensional C*-algebras in the sense of Wang. The results show in particular that the reduced C*-algebras of functions on the quantum permutation groups Sn+ are pairwise non-isomorphic for different values of n. Along the way we discuss some general facts regarding torsion in discrete quantum groups. In fact, the duals of quantum automorphism groups are the most basic examples of discrete quantum groups exhibiting genuine quantum torsion phenomena.

Award Identifier / Grant number: EP/L013916/1

Funding statement: This work was supported by the Engineering and Physical Sciences Research Council Grant EP/L013916/1 and the Polish National Science Centre grant no. 2012/06/M/ST1/00169.

References

[1] S. Baaj and G. Skandalis, Unitaires multiplicatifs et dualité pour les produits croisés de C*-algèbres, Ann. Sci. Éc. Norm. Supér. (4) 26 (1993), no. 4, 425–488. 10.24033/asens.1677Search in Google Scholar

[2] T. Banica, Fusion rules for representations of compact quantum groups, Expo. Math. 17 (1999), no. 4, 313–337. Search in Google Scholar

[3] T. Banica, Symmetries of a generic coaction, Math. Ann. 314 (1999), no. 4, 763–780. 10.1007/s002080050315Search in Google Scholar

[4] T. Banica, Quantum groups and Fuss–Catalan algebras, Comm. Math. Phys. 226 (2002), no. 1, 221–232. 10.1007/s002200200613Search in Google Scholar

[5] T. Banica, Quantum automorphism groups of small metric spaces, Pacific J. Math. 219 (2005), no. 1, 27–51. 10.2140/pjm.2005.219.27Search in Google Scholar

[6] T. Banica and J. Bichon, Quantum groups acting on 4 points, J. reine angew. Math. 626 (2009), 75–114. 10.1515/CRELLE.2009.003Search in Google Scholar

[7] T. Banica, J. Bichon and B. Collins, Quantum permutation groups: A survey, Noncommutative harmonic analysis with applications to probability, Banach Center Publ. 78, Institute of Mathematics of the Polish Academy of Sciences, Warsaw (2007), 13–34. 10.4064/bc78-0-1Search in Google Scholar

[8] R. Banica, S. Curran and R. Speicher, De Finetti theorems for easy quantum groups, Ann. Probab. 40 (2012), no. 1, 401–435. 10.1214/10-AOP619Search in Google Scholar

[9] T. Banica and R. Speicher, Liberation of orthogonal Lie groups, Adv. Math. 222 (2009), no. 4, 1461–1501. 10.1016/j.aim.2009.06.009Search in Google Scholar

[10] J. Bichon, A. De Rijdt and S. Vaes, Ergodic coactions with large multiplicity and monoidal equivalence of quantum groups, Comm. Math. Phys. 262 (2006), no. 3, 703–728. 10.1007/s00220-005-1442-2Search in Google Scholar

[11] M. Brannan, Reduced operator algebras of trace-perserving quantum automorphism groups, Doc. Math. 18 (2013), 1349–1402. 10.4171/dm/430Search in Google Scholar

[12] K. De Commer, Galois objects for algebraic quantum groups, J. Algebra 321 (2009), no. 6, 1746–1785. 10.1016/j.jalgebra.2008.11.039Search in Google Scholar

[13] A. De Rijdt and N. Vander Vennet, Actions of monoidally equivalent compact quantum groups and applications to probabilistic boundaries, Ann. Inst. Fourier (Grenoble) 60 (2010), no. 1, 169–216. 10.5802/aif.2520Search in Google Scholar

[14] J. H. Hong and W. Szymański, Quantum spheres and projective spaces as graph algebras, Comm. Math. Phys. 232 (2002), no. 1, 157–188. 10.1007/s00220-002-0732-1Search in Google Scholar

[15] J. Kustermans and S. Vaes, Locally compact quantum groups, Ann. Sci. Éc. Norm. Supér. (4) 33 (2000), no. 6, 837–934. 10.1016/S0012-9593(00)01055-7Search in Google Scholar

[16] R. Meyer, Homological algebra in bivariant K-theory and other triangulated categories. II, Tbil. Math. J. 1 (2008), 165–210. 10.32513/tbilisi/1528768828Search in Google Scholar

[17] R. Meyer and R. Nest, The Baum–Connes conjecture via localisation of categories, Topology 45 (2006), no. 2, 209–259. 10.1016/j.top.2005.07.001Search in Google Scholar

[18] R. Meyer and R. Nest, An analogue of the Baum–Connes isomorphism for coactions of compact groups, Math. Scand. 100 (2007), no. 2, 301–316. 10.7146/math.scand.a-15025Search in Google Scholar

[19] R. Meyer and R. Nest, Homological algebra in bivariant K-theory and other triangulated categories. I, Triangulated categories, London Math. Soc. Lecture Note Ser. 375, Cambridge University Press, Cambridge (2010), 236–289. 10.1017/CBO9781139107075.006Search in Google Scholar

[20] C. Mrozinski, Quantum automorphism groups and SO(3)-deformations, J. Pure Appl. Algebra 219 (2015), no. 1, 1–32. 10.1016/j.jpaa.2014.04.006Search in Google Scholar

[21] R. Nest and C. Voigt, Equivariant Poincaré duality for quantum group actions, J. Funct. Anal. 258 (2010), no. 5, 1466–1503. 10.1016/j.jfa.2009.10.015Search in Google Scholar

[22] P. Podleś, Quantum spheres, Lett. Math. Phys. 14 (1987), no. 3, 193–202. 10.1007/BF00416848Search in Google Scholar

[23] P. M. Sołtan, Quantum SO(3) groups and quantum group actions on M2, J. Noncommut. Geom. 4 (2010), no. 1, 1–28. 10.4171/JNCG/48Search in Google Scholar

[24] S. Vaes and R. Vergnioux, The boundary of universal discrete quantum groups, exactness, and factoriality, Duke Math. J. 140 (2007), no. 1, 35–84. 10.1215/S0012-7094-07-14012-2Search in Google Scholar

[25] A. Van Daele, An algebraic framework for group duality, Adv. Math. 140 (1998), no. 2, 323–366. 10.1006/aima.1998.1775Search in Google Scholar

[26] R. Vergnioux, K-amenability for amalgamated free products of amenable discrete quantum groups, J. Funct. Anal. 212 (2004), no. 1, 206–221. 10.1016/j.jfa.2003.07.017Search in Google Scholar

[27] R. Vergnioux and C. Voigt, The K-theory of free quantum groups, Math. Ann. 357 (2013), no. 1, 355–400. 10.1007/s00208-013-0902-9Search in Google Scholar

[28] C. Voigt, The Baum–Connes conjecture for free orthogonal quantum groups, Adv. Math. 227 (2011), no. 5, 1873–1913. 10.1016/j.aim.2011.04.008Search in Google Scholar

[29] C. Voigt, Quantum SU(2) and the Baum–Connes conjecture, Operator algebras and quantum groups, Banach Center Publ. 98, Institute of Mathematics of the Polish Academy of Sciences, Warsaw (2012), 417–432. 10.4064/bc98-0-17Search in Google Scholar

[30] S. Wang, Quantum symmetry groups of finite spaces, Comm. Math. Phys. 195 (1998), no. 1, 195–211. 10.1007/s002200050385Search in Google Scholar

Received: 2014-11-14
Revised: 2014-11-30
Published Online: 2015-4-3
Published in Print: 2017-11-1

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