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arXiv · 1409.8339

All-fermion electrodynamics and fermion number anomaly inflow

S. M. Kravec·John McGreevy·Brian Swingle
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Abstract

We demonstrate that 3+1-dimensional quantum electrodynamics with fermionic charges, fermionic monopoles, and fermionic dyons arises at the edge of a 4+1-dimensional gapped state with short-range entanglement. This state cannot be adiabatically connected to a product state, even in the absence of any symmetry. This provides independent evidence for the obstruction found by arXiv:1306.3238 to a 3+1-dimensional short-distance completion of all-fermion electrodynamics. The non-triviality of the bulk is demonstrated by a novel fermion number anomaly.

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S. M. Kravec, John McGreevy, Brian Swingle. 2014-09-29. All-fermion electrodynamics and fermion number anomaly inflow. https://doi.org/10.1103/physrevd.92.085024

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