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arXiv · 0911.4608

Renormalization group, dimer-dimer scattering, and three-body forces

Boris Krippa·Niels R. Walet·Michael C. Birse
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Abstract

We study the ratio between the fermion-fermion scattering length and the dimer-dimer scattering length for systems of nonrelativistic fermions, using the same functional renormalisation technique as previously applied to fermionic matter. We find a strong dependence on the cutoff function used in the renormalisation flow for a two-body truncation of the action. Adding a simple three-body term substantially reduces this dependence.

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Boris Krippa, Niels R. Walet, Michael C. Birse. 2010-03-30. Renormalization group, dimer-dimer scattering, and three-body forces. https://doi.org/10.1103/physreva.81.043628

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