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arXiv · hep-lat/0203017

New proposal for numerical simulations of theta-vacuum like systems

Vicente Azcoiti·Giuseppe Di Carlo·Angelo Galante·Victor Laliena
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Abstract

We propose a new approach to perform numerical simulations of theta-vacuum like systems, test it in two analytically solvable models, and apply it to CP^3. The main new ingredient in our approach is the method used to compute the probability distribution function of the topological charge at theta=0. We do not get unphysical phase transitions (flattening behavior of the free energy density) and reproduce the exact analytical results for the order parameter in the whole theta-range within a few percent.

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Vicente Azcoiti, Giuseppe Di Carlo, Angelo Galante, Victor Laliena. 2002-10-03. New proposal for numerical simulations of theta-vacuum like systems. https://doi.org/10.1103/physrevlett.89.141601

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