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arXiv · 1810.00230

A 2-group construction from an extension of the 3-loop group $Ω^3G$

Jouko Mickelsson·Ossi Niemimäki
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Abstract

We define a 3-loop group $Ω^3G$ as a subgroup of smooth maps from a 3-ball to a Lie group $G$, and then construct a 2-group based on an automorphic action on the Mickelsson-Faddeev extension of $Ω^3G$. In this we follow the strategy of Murray et al., who earlier described a similar construction in one dimension. The three-dimensional situation presented here is further complicated by the fact that the 3-loop group extension is not central.

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Jouko Mickelsson, Ossi Niemimäki. 2018-09-29. A 2-group construction from an extension of the 3-loop group $Ω^3G$. https://doi.org/10.1007/s11005-019-01201-y

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