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Theta-vacuum systems via real action simulations

V. Azcoiti·G. Di Carlo·A. Galante·V. Laliena
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Abstract

Inspired by the results of the Ising model within an imaginary external magnetic field, we introduce a transformation in quantum systems with a theta-vacuum term that amounts to a rescaling of z=cos(theta/2). Making use of this transformation we are able to determine the order parameter as a function of theta. The approach is successfully tested in models with both broken and unbroken CP symmetry at theta=pi.

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V. Azcoiti, G. Di Carlo, A. Galante, V. Laliena. 2003-05-07. Theta-vacuum systems via real action simulations. https://doi.org/10.1016/s0370-2693(03)00601-4

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