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Measurable Categories and 2-Groups

L. Crane·D. N. Yetter
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Abstract

Using the theory of measurable categories developped by Yetter in work in preparation, we provide a notion of representations of 2-groups more well-suited to physically and geometrically interesting examples than that proposed in unpublished work of Barrett and Mackaay using 2-VECT of Kapranov and Voevodsky. Using this theory we sketch a 2-categorical approach to the state-sum model for Lorentzian quantum gravity proposed in by the authors in previous work and suggest state-integral constructions for 4-manifold invariants.

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L. Crane, D. N. Yetter. 2003-05-12. Measurable Categories and 2-Groups. https://arxiv.org/abs/math/0305176

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