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arXiv · 2501.02479

Non-perturbative calculations of nuclear matter using in-medium similarity renormalization group

Xin Zhen·Rongzhe Hu·Haoyu Shang·Jiawei Chen·Junchen Pei·Furong Xu
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Abstract

The non-perturbative {\it ab initio} calculations of infinite nuclear matter using In-Medium Similarity Renormalization Group (IMSRG) method is developed in this work, which enables calculations with chiral two and three-nucleon forces at N$^2$LO and N$^3$LO. Results from the many-body perturbation theory at different orders and coupled-cluster theory are also presented for comparison. It is shown that different many-body approaches lead to obvious discrepancies with a harder nuclear interaction for both pure neutron matter and symmetric nuclear matter. This work provides a novel alternative infrastructure for future studies of dense nuclear matter and strongly-correlated many-body systems.

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Xin Zhen, Rongzhe Hu, Haoyu Shang, Jiawei Chen, Junchen Pei, Furong Xu. 2025-01-05. Non-perturbative calculations of nuclear matter using in-medium similarity renormalization group. https://arxiv.org/abs/2501.02479

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