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arXiv · 1902.04261

Effect of residual many-body forces due to the evolution in the in-medium similarity renormalization group method

G. Puddu
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Abstract

In the past few years in-medium similarity renormalization group methods have been introduced and developed. In these methods the Hamiltonian is evolved using a unitary transformation in order to decouple a reference state from the rest of the Hilbert space. The evolution by itself will generate, even if we start from a two-body interaction, many-body forces which are usually neglected. In this work we estimate the effect of these residual many-body forces by comparing results obtained with the Hybrid Multi-determinant method, which keeps the Hamiltonian within the two-body sector, with the corresponding ones obtained with the in-medium similarity renormalization group. Although percentage-wise the effect of neglecting these induced many-body forces is not too large, they can be appreciable depending on the nucleus, the shell model space and the harmonic oscillator frequency.

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G. Puddu. 2019-03-20. Effect of residual many-body forces due to the evolution in the in-medium similarity renormalization group method. https://doi.org/10.1088/1361-6471%2Fab0ecb

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