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DOE OSTI · 1905413

How to renormalize coupled cluster theory

Sun, Zhonghao·Bell, Charles A.·Hagen, Gaute·Papenbrock, Thomas F.
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Abstract

Coupled cluster theory is an attractive tool to solve the quantum many-body problem because its singles and doubles (CCSD) approximation is computationally affordable and yields about 90% of the correlation energy. Capturing the remaining 10%, e.g., via including triples, is numerically expensive. In this work, we assume that short-range three-body correlations dominate and—following Lepage (arXiv:nucl-th/9706029)—that their effects can be included within CCSD by renormalizing the three-body contact interaction. We renormalize this contact in 16 O and obtain systematically improved CCSD results for 24 O, 20–34 Ne, 40,48 Ca, 78 Ni, 90 Zr, and 100 Sn.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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Sun, Zhonghao, Bell, Charles A., Hagen, Gaute, Papenbrock, Thomas F.. 2022-12-05. How to renormalize coupled cluster theory. https://doi.org/10.1103/physrevc.106.l061302

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