arXiv math/03011242003-01math.OA

Some Remarks on Group Bundles and C*-dynamical systems

Ezio Vasselli

备注：: 22 pages; to appear on Comm. Math. Phys
发表信息：: Commun.Math.Phys.274 (2007) 253-276
DOI：: 10.1007/s00220-007-0268-5

英文摘要：

We introduce the notion of fibred action of a group bundle on a C(X)-algebra. By using such a notion, a characterization in terms of induced C*-bundles is given for C*-dynamical systems such that the relative commutant of the fixed-point algebra is minimal (i.e., it is generated by the centre of the given C*-algebra and the centre of the fixed-point algebra). A class of examples in the setting of the Cuntz algebra is given, and connections with superselection structures with nontrivial centre are discussed.

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