论文标题
弱磁场中热和密集的QCD物质的动量传输特性
Momentum transport properties of a hot and dense QCD matter in a weak magnetic field
论文作者
论文摘要
我们研究了在弱磁场的存在下，通过确定剪切（$η$）和散装（$ζ$）粘度在动力学理论的放松时间近似中，研究了热QCD物质的动量传输特性。 $η$和$ζ$的依赖性在存在弱磁场（$ b $ field）和有限的化学电位（$μ$）的情况下探索了温度。据观察，在存在弱磁场的情况下，剪切和散装粘度都会降低，而有限的化学势会增加这些粘度，特别是在低温下。这项研究对于通过prandtl数字（PR），通过雷诺数数（re）的流量的性质（re）的性质，通过比率$η/s $和$η/s $和$ζ/s $（$ s $（$ s $是熵密度），流动的流动性和位置非常重要。观察到PRANDTL的数量在弱磁场中增加，而有限的化学势的存在与缺少$ B $ field和$μ$的情况相比，其幅度降低了。但是，PR仍然比统一更大，表明由于衰减而引起的能量耗散主要受动量扩散的控制。注意到，弱磁场使雷诺数数量更大，而化学电位使其在没有$ b $ field和$μ$的情况下小于该数字。我们已经观察到，在弱磁场状态下，比率$η/s $减小，而有限的化学电位增加了其值，但是在存在弱磁场和有限化学势的存在下，比率$ζ/s $可以减少。
We have studied the momentum transport properties of a hot and dense QCD matter in the presence of weak magnetic field by determining the shear ($η$) and bulk ($ζ$) viscosities in the relaxation time approximation of kinetic theory. The dependence of $η$ and $ζ$ on the temperature has been explored in the presence of weak magnetic field ($B$-field) and finite chemical potential ($μ$). It is observed that both shear and bulk viscosities get decreased in the presence of a weak magnetic field, whereas the finite chemical potential increases these viscosities, specifically at low temperatures. This study is important to understand the sound attenuation through the Prandtl number (Pr), the nature of the flow through the Reynolds number (Re), the fluidity and location of transition point of the matter through the ratios $η/s$ and $ζ/s$ ($s$ is the entropy density), respectively. The Prandtl number is observed to increase in the weak magnetic field, whereas the presence of a finite chemical potential reduces its magnitude as compared to the scenario of absence of $B$-field and $μ$. However, Pr still remains larger than unity, indicating that the energy dissipation due to the sound attenuation is mostly governed by the momentum diffusion. It is noticed that the weak magnetic field makes the Reynolds number larger, whereas the chemical potential makes it smaller than that in the absence of $B$-field and $μ$. We have observed that the ratio $η/s$ decreases in the weak magnetic field regime, whereas the finite chemical potential increases its value, but the ratio $ζ/s$ is found to decrease in the presence of weak magnetic field as well as finite chemical potential.
