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arXiv · 1602.03441

Higher Gauge Theory with String 2-Groups

Getachew Alemu Demessie·Christian Saemann
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Abstract

We give a complete and explicit description of the kinematical data of higher gauge theory on principal 2-bundles with the string 2-group model of Schommer-Pries as structure 2-group. We start with a self-contained review of the weak 2-category Bibun of Lie groupoids, bibundles and bibundle morphisms. We then construct categories internal to Bibun, which allow us to define principal 2-bundles with 2-groups internal to Bibun as structure 2-groups. Using these, we Lie-differentiate the 2-group model of the string group and we obtain the well-known string Lie 2-algebra. Generalizing the differentiation process, we find Maurer-Cartan forms leading us to higher non-abelian Deligne cohomology, encoding the kinematical data of higher gauge theory together with their (finite) gauge symmetries. We end by discussing an example of non-abelian self-dual strings in this setting.

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BibTeXRIS

Getachew Alemu Demessie, Christian Saemann. 2016-02-10. Higher Gauge Theory with String 2-Groups. https://doi.org/10.4310/atmp.2017.v21.n8.a2

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