Causality, universality, and effective field theory for van der Waals interactions
Abstract
We analyze low-energy scattering for arbitrary short-range interactions plus an attractive 1/r^6 tail. We derive the constraints of causality and unitarity and find that the van der Waals length scale dominates over parameters characterizing the short-distance physics of the interaction. This separation of scales suggests a separate universality class for physics characterizing interactions with an attractive 1/r^6 tail. We argue that a similar universality class exists for any attractive potential 1/r^{alpha} for alpha >= 2. We also discuss the extension to multi-channel systems near a magnetic Feshbach resonance. We discuss the implications for effective field theory with attractive singular power law tails.
Cite
@article{arxiv.1303.5261,
title = {Causality, universality, and effective field theory for van der Waals interactions},
author = {Serdar Elhatisari and Sebastian König and Dean Lee and H. -W. Hammer},
journal= {arXiv preprint arXiv:1303.5261},
year = {2013}
}
Comments
19 pages, 3 figures, version published in Phys. Rev. A