Half-integral levels

Yifei Zhao

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arXiv · 2312.11058

Half-integral levels

Yifei Zhao

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Abstract

We construct equivalences among four notions associated to a reductive group scheme $G$: factorization super central extensions of the loop group of $G$ by $\mathbb G_m$ subject to a condition on the commutator, factorization super line bundles on the affine Grassmannian of $G$, rigidified sections of a quotient of $2$-truncated K-theory over the Zariski classifying stack of $G$, and combinatorial data defined by Brylinski and Deligne in a conjectural extension of their classification theorem.

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BibTeX RIS

Yifei Zhao. 2023-12-18. Half-integral levels. https://arxiv.org/abs/2312.11058

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