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arXiv · 1909.07383

Lorentz Symmetry Fractionalization and Dualities in (2+1)d

Po-Shen Hsin·Shu-Heng Shao
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Abstract

We discuss symmetry fractionalization of the Lorentz group in (2+1)$d$ non-spin quantum field theory (QFT), and its implications for dualities. We prove that two inequivalent non-spin QFTs are dual as spin QFTs if and only if they are related by a Lorentz symmetry fractionalization with respect to an anomalous $\mathbb{Z}_2$ one-form symmetry. Moreover, if the framing anomalies of two non-spin QFTs differ by a multiple of 8, then they are dual as spin QFTs if and only if they are also dual as non-spin QFTs. Applications to summing over the spin structures, time-reversal symmetry, and level/rank dualities are explored. The Lorentz symmetry fractionalization naturally arises in Chern-Simons matter dualities that obey certain spin/charge relations, and is instrumental for the dualities to hold when viewed as non-spin theories.

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Po-Shen Hsin, Shu-Heng Shao. 2019-09-16. Lorentz Symmetry Fractionalization and Dualities in (2+1)d. https://doi.org/10.21468/scipostphys.8.2.018

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