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arXiv · 1610.07010

On time-reversal anomaly of 2+1d topological phases

Yuji Tachikawa·Kazuya Yonekura
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Abstract

We describe a method to find the anomaly of the time-reversal symmetry of 2+1d topological quantum field theories, by computing the fractional anomalous momentum on the cross-cap background. This allows us, for example, to identify the parameter $ν$ mod 16 of the bulk 3+1d topological superconductor with $\mathsf{T}^2=(-1)^F$ on whose boundary a given 2+1d time-reversal-invariant topological phase can appear.

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Yuji Tachikawa, Kazuya Yonekura. 2016-10-22. On time-reversal anomaly of 2+1d topological phases. https://doi.org/10.1093/ptep%2Fptx010

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