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arXiv · 0708.1602

Three-Body Forces Produced by a Similarity Renormalization Group Transformation in a Simple Model

S. K. Bogner·R. J. Furnstahl·R. J. Perry
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Abstract

A simple class of unitary renormalization group transformations that force hamiltonians towards a band-diagonal form produce few-body interactions in which low- and high-energy states are decoupled, which can greatly simplify many-body calculations. One such transformation has been applied to phenomenological and effective field theory nucleon-nucleon interactions with success, but further progress requires consistent treatment of at least the three-nucleon interaction. In this paper we demonstrate in an extremely simple model how these renormalization group transformations consistently evolve two- and three-body interactions towards band-diagonal form, and introduce a diagrammatic approach that generalizes to the realistic nuclear problem.

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S. K. Bogner, R. J. Furnstahl, R. J. Perry. 2007-10-25. Three-Body Forces Produced by a Similarity Renormalization Group Transformation in a Simple Model. https://doi.org/10.1016/j.aop.2007.09.001

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