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arXiv · 1208.0375

A practical solution to the sign problem at finite theta-vacuum angle

Takahiro Sasaki·Hiroaki Kouno·Masanobu Yahiro
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Abstract

We propose a practical way of circumventing the sign problem in lattice QCD simulations with a theta-vacuum term. This method is the reweighting method for the QCD Lagrangian after the U_A(1) transformation. In the Lagrangian, the P-odd mass term as a cause of the sign problem is minimized. In order to find out a good reference system in the reweighting method, we estimate the average reweighting factor by using the two-flavor NJL model and eventually find a good reference system.

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Takahiro Sasaki, Hiroaki Kouno, Masanobu Yahiro. 2012-08-01. A practical solution to the sign problem at finite theta-vacuum angle. https://doi.org/10.1103/physrevd.87.056003

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