AI 中文总结
本研究针对夸克-双夸克模型泛函重整化群流中低温大化学势下的负扩散问题，证明其为模型特性，提出超扩散正则化方案以消除振荡，为研究QCD相图相关现象提供可靠方法。
AI 中文摘要
我们在局域势近似下采用泛函重整化群（FRG）研究夸克-双夸克模型（QDM）。在近期一项工作[arXiv:2510.01066 [hep-ph]]中，报道了在低温大夸克化学势下应用该方法时存在问题，这些问题被归因于数值伪影。本研究将这些问题的根源追溯到有效势导数的FRG流过程中出现负扩散系数，导致该量发生强烈振荡。我们证明负扩散是模型特性而非数值伪影，提出引入超扩散项的正则化方案以消除这些振荡，并展示其在QDM相图研究中的有效性。正则化FRG流中的负扩散对可靠研究色超导、非均匀相等现象尤为重要，这些现象可能出现在QCD相图的高密度低温区域。
英文摘要
We investigate the Quark-Diquark Model (QDM) with the Functional Renormalization Group (FRG) in the Local Potential Approximation. In a recent work [arXiv:2510.01066 [hep-ph]], problems were reported in applying this method at low temperatures and large quark chemical potentials, which were attributed to numerical artifacts. In this work, we trace the origin of these problems to the occurrence of a negative diffusion coefficient during the FRG flow of the derivative of the effective potential, leading to strong oscillations of the latter quantity. We show that negative diffusion is a model feature and not a numerical artifact. We propose a regularization scheme which introduces a hyperdiffusion term to remove these oscillations and demonstrate its effectiveness for studies of the phase diagram of the QDM. Regularizing the negative diffusion in the FRG flow is particularly important to reliably study phenomena such as color superconductivity and inhomogeneous phases, which might emerge in the high-density, low-temperature region of the QCD phase diagram.
Comments12 pages, 4 figures
