Critical dynamics within the real-time fRG approach

Yong-rui Chen; Yang-yang Tan; Wei-jie Fu

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arXiv · 2312.05870

Critical dynamics within the real-time fRG approach

Yong-rui Chen·Yang-yang Tan·Wei-jie Fu

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Abstract

The Schwinger-Keldysh functional renormalization group (fRG) developed in [1] is employed to investigate critical dynamics related to a second-order phase transition. The effective action of model A is expanded to the order of $O(\partial^2)$ in the derivative expansion for the $O(N)$ symmetry. By solving the fixed-point equations of effective potential and wave function, we obtain static and dynamic critical exponents for different values of the spatial dimension $d$ and the field component number $N$. It is found that one has $z \geq 2$ in the whole range of $2\leq d\leq 4$ for the case of $N=1$, while in the case of $N=4$ the dynamic critical exponent turns to $z < 2$ when the dimension approach towards $d=2$.

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Yong-rui Chen, Yang-yang Tan, Wei-jie Fu. 2023-12-10. Critical dynamics within the real-time fRG approach. https://arxiv.org/abs/2312.05870

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