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arXiv · 1701.07182

Classification of sign-problem-free relativistic fermions on the basis of the Majorana positivity

Tomoya Hayata·Arata Yamamoto
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Abstract

We classify the sign-problem-free relativistic fermion actions on the basis of the Majorana representation. In the Majorana representation, the sign-problem-free condition is given by the semi-positivity of a Pfaffian. We show that the known sign-problem-free actions of the Dirac fermions, which are usually understood from the semi-positivity of a determinant, e.g., the action of quantum chromodynamics with nonzero chiral chemical potential or nonzero isospin chemical potential, can also be understood from the semi-positivity of a Pfaffian. We also derive new classes of the sign-problem-free relativistic fermion actions with Majorana-type source terms.

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Tomoya Hayata, Arata Yamamoto. 2017-01-25. Classification of sign-problem-free relativistic fermions on the basis of the Majorana positivity. https://doi.org/10.1093/ptep%2Fptx040

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