The research status of the shear viscosity of nucleonic matter is reviewed. Some methods to calculate the shear viscosity of nucleonic matter are introduced, including mean free path, Green–Kubo, shear strain rate, Chapman–Enskog and relaxation time approximation. Based on these methods, results for infinite and finite nucleonic matter are discussed, which are attempts to investigate the universality of the ratio of shear viscosity over entropy density and transport characteristics like the liquid–gas phase transition in nucleonic matter. In addition, shear viscosity is also briefly discussed for the quantum chrodynamical matter produced in relativistic heavy-ion collisions.

中文翻译：

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核子物质的剪切粘度

综述了核子物质剪切粘度的研究现状。介绍了计算核子物质剪切粘度的一些方法，包括平均自由程、Green-Kubo、剪切应变率、Chapman-Enskog 和弛豫时间近似。基于这些方法，讨论了无限和有限核物质的结果，试图研究剪切粘度与熵密度之比的普遍性以及核物质中液-气相变等输运特性。此外，还简要讨论了相对论性重离子碰撞中产生的量子热力学物质的剪切粘度。