Nonperturbative Renormalisation Group: Applications to the few and many-body systems
Abstract
We consider the applications of functional renormalisation group to few and many-body systems. As an application to the few-body dynamics we study the ratio between the fermion-fermion scattering length and the dimer-dimer scattering length for systems of few nonrelativistic fermions. 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. In the context of many-body physics we study the dynamics of both symmetric and asymmetric many-fermion systems using the same functional renormalisation technique. It is demonstrated that functional renormalisation group gives sensible and reliable results and provides a solid theoretical ground for the future studies. Open questions as well as lines of further developments are discussed.
Keywords
Cite
@article{arxiv.0912.3665,
title = {Nonperturbative Renormalisation Group: Applications to the few and many-body systems},
author = {B. Krippa},
journal= {arXiv preprint arXiv:0912.3665},
year = {2015}
}
Comments
Talk on International IUPAP Conference on Few-Body Problems in Physics, September, 2009, Bonn, Germany