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arXiv · 2205.12990

How to renormalize coupled cluster theory

Z. H. Sun·C. A. Bell·G. Hagen·T. Papenbrock
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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. Here we assume that short-range three-body correlations dominate and - following Lepage [How to renormalize the Schr\"odinger equation, 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 accurate CCSD results for $^{24}$O, $^{20-34}$Ne, $^{40,48}$Ca, $^{78}$Ni, $^{90}$Zr, and $^{100}$Sn.

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Z. H. Sun, C. A. Bell, G. Hagen, T. Papenbrock. 2022-05-25. How to renormalize coupled cluster theory. https://doi.org/10.1103/physrevc.106.l061302

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