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Strong CP problem, Neutron EDM and Thermal QCD sum rules

Mohamed Chabab
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Abstract

The behaviour of the broken CP symmetry at finite temperature is examined. This is achieved through the investigation of the neutron electric dipole moment $d_n$ induced by $θ$-term. By using thermal QCD sum rules, we find that below the critical temperature, the ratio $\mid {d_n \over \barθ}\mid$ slightly decreases but survives at temperature effects. This evolution implies that CP remains broken at finite temperature as required by Baryogenesis \cite{Chabab}.

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Mohamed Chabab. 2003-11-20. Strong CP problem, Neutron EDM and Thermal QCD sum rules. https://doi.org/10.1063/1.1799782

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