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arXiv · 1009.3880

Many-body fits of phase-equivalent effective interactions

Calvin W. Johnson
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Abstract

In many-body theory it is often useful to renormalize short-distance, high-momentum components of an interaction via unitary transformations. Such transformations preserve the on-shell physical observables of the two-body system (mostly phase-shifts, hence unitarily-connected effective interactions are often called phase-equivalent), while modifying off-shell T-matrix elements influential in many-body systems. In this paper I lay out a general and systematic approach for controlling the off-shell behavior of an effective interaction, which can be adjusted to many-body properties, and present an application to trapped fermions at the unitary

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Calvin W. Johnson. 2010-09-20. Many-body fits of phase-equivalent effective interactions. https://doi.org/10.1103/physrevc.82.031303

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