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arXiv · 1111.4536

Minimal Doubling Fermion and Hermiticity

Syo Kamata·Hidekazu Tanaka
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Abstract

We analyze the lattice fermion kinetic term using PT symmetry, R-hermiticity, and $\gamma_{5}$-hermiticity. R-hermiticity is a condition for Hermite action and it is related to $\gamma_{5}$-hermiticity and PT symmetry. Assuming that a translation-invariant kinetic term with continuum and periodic function does not have PT symmetry, it can have R-hermiticity or $\gamma_{5}$-hermiticity. We prove that a kinetic term with continuum and periodic function that is PT symmetric does not reduce doublers. As a simple example, we analyze the two-dimensional two-flavor Gross-Neveu model with minimal doubling fermions. The minimal doubling fermions break PT symmetry and R-hermiticity, hence complex or non-Hermite coupling constants are caused by quantum correction.

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Syo Kamata, Hidekazu Tanaka. 2011-11-19. Minimal Doubling Fermion and Hermiticity. https://doi.org/10.1093/ptep/pts093

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