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arXiv · 1806.07594

Shear viscosity of ultrarelativistic Boson systems in the presence of a Bose-Einstein condensate

Zhengyu Chen·Carsten Greiner·Zhe Xu·Pengfei Zhuang
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Abstract

We calculate for the first time the shear viscosity of ultrarelativistic Boson systems in the presence of a Bose-Einstein condensate (BEC). Two different methods are used. One is the Grad's method of moments and another is the Green-Kubo relation within a kinetic transport approach. In this work we consider a Boson system with isotropic elastic collisions and a gluon system with elastic scatterings described by perturbation QCD (pQCD). The results show that the presence of a BEC lowers the shear viscosity. This effect becomes stronger for the increasing proportion of the BEC in the Boson system and is insensitive to the detail of interactions.

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Zhengyu Chen, Carsten Greiner, Zhe Xu, Pengfei Zhuang. 2019-11-18. Shear viscosity of ultrarelativistic Boson systems in the presence of a Bose-Einstein condensate. https://doi.org/10.1103/physrevc.100.014906

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