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arXiv · hep-th/0312134

U-duality (sub-)groups and their topology

Arjan Keurentjes
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Abstract

We discuss some consequences of the fact that symmetry groups appearing in compactified (super-)gravity may be non-simply connected. The possibility to add fermions to a theory results in a simple criterion to decide whether a 3-dimensional coset sigma model can be interpreted as a dimensional reduction of a higher dimensional theory. Similar criteria exist for higher dimensional sigma models, though less decisive. Careful examination of the topology of symmetry groups rules out certain proposals for M-theory symmetries, which are not ruled out at the level of the algebra's. We conclude with an observation on the relation between the ``generalized holonomy'' proposal, and the actual symmetry groups resulting from E_10 and E_11 conjectures.

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Arjan Keurentjes. 2003-12-12. U-duality (sub-)groups and their topology. https://doi.org/10.1088/0264-9381%2F21%2F10%2F009

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