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arXiv · 1502.05089

Transgressive loop group extensions

Konrad Waldorf
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Abstract

A central extension of the loop group of a Lie group is called transgressive, if it corresponds under transgression to a degree four class in the cohomology of the classifying space of the Lie group. Transgressive loop group extensions are those that can be explored by finite-dimensional, higher-categorical geometry over the Lie group. We show how transgressive central extensions can be characterized in a loop-group theoretical way, in terms of loop fusion and thin homotopy equivariance.

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Konrad Waldorf. 2016-01-11. Transgressive loop group extensions. https://doi.org/10.1007/s00209-016-1764-0

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