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arXiv · 2109.09631

Green-Kubo formula for Boltzmann and Fermi-Dirac statistics

X. G. Deng·Y. G. Ma·Y. X. Zhang
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Abstract

Shear viscosity of nuclear matter is extracted via the Green-Kubo formula and the Gaussian thermostated SLLOD algorithm (the shear rate method) in a periodic box by using an improved quantum molecular dynamic (ImQMD) model without mean field, also it is calculated by a Boltzmann-type equation. Here a new form of the Green-Kubo formula is put forward in the present work. For classical limit at nuclear matter densities of $0.4\rho_{0}$ and $1.0\rho_{0}$, shear viscosity by the traditional and new form of the Green-Kubo formula as well as the SLLOD algorithm are coincident with each other. However, for non-classical limit, shear viscosity by the traditional form of the Green-Kubo formula is higher than those obtained by the new form of the Green-Kubo formula as well as the SLLOD algorithm especially in low temperature region. In addition, shear viscosity from the Boltzmann-type equation is found to be less than that by the Green-Kubo method or the SLLOD algorithm for both classical and non-classical limits.

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X. G. Deng, Y. G. Ma, Y. X. Zhang. 2021-09-20. Green-Kubo formula for Boltzmann and Fermi-Dirac statistics. https://doi.org/10.1140/epja%2Fs10050-021-00550-4

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