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arXiv · 1907.02522

The "non-regularizability" of gapless free fermion Hamiltonian protected by on-site symmetries

Yen-Ta Huang·Lokman Tsui·Dung-Hai Lee
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Abstract

The non-regularizability of free fermion field theories, which is the root of various quantum anomalies, plays a central role in particle physics and modern condensed matter physics. In this paper, we generalize the Nielsen-Ninomiya theorem to all minimal nodal free fermion field theories protected by the time reversal, charge conservation, and charge conjugation symmetries. We prove that these massless field theories cannot be regularized on a lattice.

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Yen-Ta Huang, Lokman Tsui, Dung-Hai Lee. 2019-07-04. The "non-regularizability" of gapless free fermion Hamiltonian protected by on-site symmetries. https://doi.org/10.1016/j.nuclphysb.2020.115005

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