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$θ$ Vacuum in a Random Matrix Model

Romuald A. Janik·Maciej A. Nowak·Gabor Papp·Ismail Zahed
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Abstract

Inspired by recent lattice calculations, we model certain aspects of the $θ$-vacuum using a matrix model with gaussian weights. The vacuum energy exhibits a cusp at $θ<π$ that is sensitive to both the accuracy of the numerical analysis and the maximum density of winding modes present in a finite volume.

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Romuald A. Janik, Maciej A. Nowak, Gabor Papp, Ismail Zahed. 1999-05-11. $θ$ Vacuum in a Random Matrix Model. https://arxiv.org/abs/hep-ph/9905306

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