Abstract
C*-quantum groups with projection are the noncommutative analogues of semidirect products of groups. Radford’s Theorem about Hopf algebras with projection suggests that any C*-quantum group with projection decomposes uniquely into an ordinary C*-quantum group and a “braided” C*-quantum group. We establish this on the level of manageable multiplicative unitaries.
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Communicated by Y. Kawahigashi
Supported by the German Research Foundation (Deutsche Forschungsgemeinschaft (DFG)) through the Research Training Group 1493. The second author was also supported by a Fields–Ontario postdoctoral fellowship. The third author was partially supported by the Alexander von Humboldt-Stiftung and the National Science Center (NCN), grant 2015/17/B/ST1/00085.
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Meyer, R., Roy, S. & Woronowicz, S.L. Semidirect Products of C*-Quantum Groups: Multiplicative Unitaries Approach. Commun. Math. Phys. 351, 249–282 (2017). https://doi.org/10.1007/s00220-016-2727-3
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DOI: https://doi.org/10.1007/s00220-016-2727-3