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Theta vacuum effects on the chiral condensation and the eta^prime meson correlators in the two-flavor massive QED_2 on the lattice

Hidenori Fukaya·Tetsuya Onogi
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Abstract

We study the scalar and pseudoscalar condensations and the eta^prime meson correlators of the two-flavor massive Schwinger model in the non-zero theta vacuum. Exploiting our new method which was developed to investigate topological effects in the previous work, we find that the pseudoscalar condensation is non-zero and there exists a long-range correlation of the eta^prime meson. This phenomenon is well described by the clustering property. We also find that even in theta=0 case the cancellation of the long-range correlation is nontrivial and requires accurate contributions from higher topological sectors. Our results imply that the fluctuation of the ``disconnected'' diagram originates from the pseudoscalar condensation in each topological sector.

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Hidenori Fukaya, Tetsuya Onogi. 2004-04-07. Theta vacuum effects on the chiral condensation and the eta^prime meson correlators in the two-flavor massive QED_2 on the lattice. https://doi.org/10.1103/physrevd.70.054508

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