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arXiv · 2012.11622

Some comments on 6d global gauge anomalies

Yasunori Lee·Yuji Tachikawa
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Abstract

Global gauge anomalies in $6d$ associated with non-trivial homotopy groups $\pi_6(G)$ for $G=SU(2)$, $SU(3)$, and $G_2$ were computed and utilized in the past. In the modern bordism point of view of anomalies, however, they come from the bordism groups $\Omega^\text{spin}_7(BG)$, which are in fact trivial and therefore preclude their existence. Instead, it was noticed that a proper treatment of the $6d$ Green-Schwarz mechanism reproduces the same anomaly cancellation conditions derived from $\pi_6(G)$. In this paper, we revisit and clarify the relation between these two different approaches.

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Yasunori Lee, Yuji Tachikawa. 2020-12-21. Some comments on 6d global gauge anomalies. https://arxiv.org/abs/2012.11622

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