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تسجيل مستخدم جديدEffect of residual many-body forces due to the evolution in the in-medium similarity renormalization group method
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G. Puddu
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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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We present a pedagogical discussion of Similarity Renormalization Group (SRG) methods, in particular the In-Medium SRG (IMSRG) approach for solving the nuclear many-body problem. These methods use continuous unitary transformations to evolve the nucl
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