AI 中文总结
本文采用泛函重整化群实时形式，研究³He-⁴He混合物与含两无质量夸克味的QCD的三临界动力学，揭示其强动力学标度特性及与QCD临界点慢涨落的关联。
AI 中文摘要
本文研究了³He-⁴He混合物以及具有两个无质量夸克味的QCD中三临界点附近的普适临界动力学。具体而言，我们采用泛函重整化群的实时形式，探究三临界区域如何将两味手征相变的O(4)模型G动力学，与具有明显手征对称性破缺的QCD临界点的模型H动力学连接起来。我们证明，在存在额外亚扩散类能量密度的情况下，三临界动力学继承了模型G的强动力学标度，其中序参量与守恒O(N)荷的临界涨落以相同速率弛豫。与λ线及液态³He-⁴He混合物中三临界点相关的平面O(2)情形下的强标度，作为一个有趣的极限情形出现。在QCD中计入有限轻夸克质量导致的明显对称性破缺后，三临界动力学的类能量密度会与Z₂序参量线性混合，最终产生QCD临界点附近每重子熵的特征慢涨落。
英文摘要
In this paper we study the universal critical dynamics near the tricritical points in $\mathrm{^3He}$-$\mathrm{^4He}$ mixtures and QCD with two massless quark flavors. In particular, we use the real-time formulation of the functional renormalization group to understand how the tricritical region connects the $O(4)$ Model G dynamics of the two-flavor chiral phase transition to that of Model H for the QCD critical point with explicitly broken chiral symmetry. We show that in presence of an additional subdiffusive energy-like density, the tricritical dynamics inherits the strong dynamic scaling of Model G, where the critical fluctuations of order parameter and conserved $O(N)$ charges relax at identical rates. The strong scaling in the planar $O(2)$ case relevant for the $λ$-line and the tricritical point in the liquid $\mathrm{^3He}$-$\mathrm{^4He}$ mixtures arises as an interesting limiting case. Including the explicit symmetry breaking by the finite light-quark masses in QCD, the energy-like density of the tricritical dynamics mixes linearly with the $Z_2$ order parameter to eventually produce the characteristic slow fluctuations of the entropy per baryon near the QCD critical point.
Comments22 pages, 7 figures
