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arXiv · 1610.00707

Heterotic sigma models on $T^8$ and the Borcherds automorphic form $Φ_{12}$

Sarah M. Harrison·Shamit Kachru·Natalie M. Paquette·Roberto Volpato·Max Zimet
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Abstract

We consider the spectrum of BPS states of the heterotic sigma model with $(0,8)$ supersymmetry and $T^8$ target, as well as its second-quantized counterpart. We show that the counting function for such states is intimately related to Borcherds' automorphic form $Φ_{12}$, a modular form which exhibits automorphy for $O(2,26;{\mathbb Z})$. We comment on possible implications for Umbral moonshine and theories of AdS$_3$ gravity.

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Sarah M. Harrison, Shamit Kachru, Natalie M. Paquette, Roberto Volpato, Max Zimet. 2017-07-16. Heterotic sigma models on $T^8$ and the Borcherds automorphic form $Φ_{12}$. https://doi.org/10.1007/jhep10(2017)121

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