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arXiv · 1708.08936

Generalised diffeomorphisms for E$_9$

Guillaume Bossard·Martin Cederwall·Axel Kleinschmidt·Jakob Palmkvist·Henning Samtleben
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Abstract

We construct generalised diffeomorphisms for E$_9$ exceptional field theory. The transformations, which like in the E$_8$ case contain constrained local transformations, close when acting on fields. This is the first example of a generalised diffeomorphism algebra based on an infinite-dimensional Lie algebra and an infinite-dimensional coordinate module. As a byproduct, we give a simple generic expression for the invariant tensors used in any extended geometry. We perform a generalised Scherk--Schwarz reduction and verify that our transformations reproduce the structure of gauged supergravity in two dimensions. The results are valid also for other affine algebras.

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Guillaume Bossard, Martin Cederwall, Axel Kleinschmidt, Jakob Palmkvist, Henning Samtleben. 2017-08-29. Generalised diffeomorphisms for E$_9$. https://doi.org/10.1103/physrevd.96.106022

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